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Message-ID: <2bb97268e055b1dd3b3c01c4cbeb54446930e002.camel@redhat.com>
Subject: Re: [PATCH 5.15 011/107] drm/i915/backlight: extract backlight code
 to a separate file
From:   Lyude Paul <lyude@redhat.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org
Cc:     stable@vger.kernel.org, Jani Nikula <jani.nikula@intel.com>,
        Sasha Levin <sashal@kernel.org>
Date:   Tue, 06 Sep 2022 18:13:17 -0400
In-Reply-To: <20220906132822.225236433@linuxfoundation.org>
References: <20220906132821.713989422@linuxfoundation.org>
         <20220906132822.225236433@linuxfoundation.org>
Organization: Red Hat Inc.
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Were there parts of this series that weren't Cc'd to me via email? Trying to
understand why this patch would be pulled in since it might be required for
other fixes, but on it's own there should be no functional changes so it's not
really a candidate for stable.

On Tue, 2022-09-06 at 15:29 +0200, Greg Kroah-Hartman wrote:
> From: Jani Nikula <jani.nikula@intel.com>
> 
> [ Upstream commit 6cc42fbeb150ff33b17cbf108713ca4be23994d8 ]
> 
> In a long overdue refactoring, split out backlight code to new
> intel_backlight.[ch]. Simple code movement, leave renames for follow-up
> work. No functional changes.
> 
> Cc: Lyude Paul <lyude@redhat.com>
> Reviewed-by: Lyude Paul <lyude@redhat.com>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> Link: https://patchwork.freedesktop.org/patch/msgid/97d310848f03061473b9b2328e2c5c4dcf263cfa.1629888677.git.jani.nikula@intel.com
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/gpu/drm/i915/Makefile                 |    1 +
>  drivers/gpu/drm/i915/display/g4x_dp.c         |    2 +-
>  drivers/gpu/drm/i915/display/icl_dsi.c        |    1 +
>  .../gpu/drm/i915/display/intel_backlight.c    | 1778 +++++++++++++++++
>  .../gpu/drm/i915/display/intel_backlight.h    |   51 +
>  .../gpu/drm/i915/display/intel_connector.c    |    4 +-
>  drivers/gpu/drm/i915/display/intel_ddi.c      |    2 +-
>  drivers/gpu/drm/i915/display/intel_dp.c       |    1 +
>  .../drm/i915/display/intel_dp_aux_backlight.c |    2 +-
>  drivers/gpu/drm/i915/display/intel_lvds.c     |    1 +
>  drivers/gpu/drm/i915/display/intel_opregion.c |    3 +-
>  drivers/gpu/drm/i915/display/intel_panel.c    | 1767 +---------------
>  drivers/gpu/drm/i915/display/intel_panel.h    |   34 +-
>  drivers/gpu/drm/i915/display/vlv_dsi.c        |    1 +
>  14 files changed, 1843 insertions(+), 1805 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/display/intel_backlight.c
>  create mode 100644 drivers/gpu/drm/i915/display/intel_backlight.h
> 
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index 26cf754229451..9d371be7dc5cd 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -249,6 +249,7 @@ i915-y += \
>  	display/g4x_dp.o \
>  	display/g4x_hdmi.o \
>  	display/icl_dsi.o \
> +	display/intel_backlight.o \
>  	display/intel_crt.o \
>  	display/intel_ddi.o \
>  	display/intel_ddi_buf_trans.o \
> diff --git a/drivers/gpu/drm/i915/display/g4x_dp.c b/drivers/gpu/drm/i915/display/g4x_dp.c
> index de0f358184aa3..29c0eca647e34 100644
> --- a/drivers/gpu/drm/i915/display/g4x_dp.c
> +++ b/drivers/gpu/drm/i915/display/g4x_dp.c
> @@ -7,6 +7,7 @@
>  
>  #include "g4x_dp.h"
>  #include "intel_audio.h"
> +#include "intel_backlight.h"
>  #include "intel_connector.h"
>  #include "intel_de.h"
>  #include "intel_display_types.h"
> @@ -16,7 +17,6 @@
>  #include "intel_fifo_underrun.h"
>  #include "intel_hdmi.h"
>  #include "intel_hotplug.h"
> -#include "intel_panel.h"
>  #include "intel_pps.h"
>  #include "intel_sideband.h"
>  
> diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
> index 638a00b2dc2d2..2601873e15466 100644
> --- a/drivers/gpu/drm/i915/display/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/display/icl_dsi.c
> @@ -29,6 +29,7 @@
>  #include <drm/drm_mipi_dsi.h>
>  
>  #include "intel_atomic.h"
> +#include "intel_backlight.h"
>  #include "intel_combo_phy.h"
>  #include "intel_connector.h"
>  #include "intel_crtc.h"
> diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c
> new file mode 100644
> index 0000000000000..4b0086ee48519
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/display/intel_backlight.c
> @@ -0,0 +1,1778 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright © 2021 Intel Corporation
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/pwm.h>
> +
> +#include "intel_backlight.h"
> +#include "intel_connector.h"
> +#include "intel_de.h"
> +#include "intel_display_types.h"
> +#include "intel_dp_aux_backlight.h"
> +#include "intel_dsi_dcs_backlight.h"
> +#include "intel_panel.h"
> +
> +/**
> + * scale - scale values from one range to another
> + * @source_val: value in range [@source_min..@source_max]
> + * @source_min: minimum legal value for @source_val
> + * @source_max: maximum legal value for @source_val
> + * @target_min: corresponding target value for @source_min
> + * @target_max: corresponding target value for @source_max
> + *
> + * Return @source_val in range [@source_min..@source_max] scaled to range
> + * [@target_min..@target_max].
> + */
> +static u32 scale(u32 source_val,
> +		 u32 source_min, u32 source_max,
> +		 u32 target_min, u32 target_max)
> +{
> +	u64 target_val;
> +
> +	WARN_ON(source_min > source_max);
> +	WARN_ON(target_min > target_max);
> +
> +	/* defensive */
> +	source_val = clamp(source_val, source_min, source_max);
> +
> +	/* avoid overflows */
> +	target_val = mul_u32_u32(source_val - source_min,
> +				 target_max - target_min);
> +	target_val = DIV_ROUND_CLOSEST_ULL(target_val, source_max - source_min);
> +	target_val += target_min;
> +
> +	return target_val;
> +}
> +
> +/*
> + * Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
> + * to [hw_min..hw_max].
> + */
> +static u32 clamp_user_to_hw(struct intel_connector *connector,
> +			    u32 user_level, u32 user_max)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +	u32 hw_level;
> +
> +	hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
> +	hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
> +
> +	return hw_level;
> +}
> +
> +/* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
> +static u32 scale_hw_to_user(struct intel_connector *connector,
> +			    u32 hw_level, u32 user_max)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +
> +	return scale(hw_level, panel->backlight.min, panel->backlight.max,
> +		     0, user_max);
> +}
> +
> +u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
> +
> +	if (dev_priv->params.invert_brightness < 0)
> +		return val;
> +
> +	if (dev_priv->params.invert_brightness > 0 ||
> +	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
> +		return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min;
> +	}
> +
> +	return val;
> +}
> +
> +void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 val)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *i915 = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val);
> +	panel->backlight.pwm_funcs->set(conn_state, val);
> +}
> +
> +u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 val)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	drm_WARN_ON_ONCE(&dev_priv->drm,
> +			 panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
> +
> +	val = scale(val, panel->backlight.min, panel->backlight.max,
> +		    panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
> +
> +	return intel_panel_invert_pwm_level(connector, val);
> +}
> +
> +u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	drm_WARN_ON_ONCE(&dev_priv->drm,
> +			 panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
> +
> +	if (dev_priv->params.invert_brightness > 0 ||
> +	    (dev_priv->params.invert_brightness == 0 && dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS))
> +		val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min);
> +
> +	return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max,
> +		     panel->backlight.min, panel->backlight.max);
> +}
> +
> +static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
> +}
> +
> +static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> +}
> +
> +static u32 i9xx_get_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 val;
> +
> +	val = intel_de_read(dev_priv, BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> +	if (DISPLAY_VER(dev_priv) < 4)
> +		val >>= 1;
> +
> +	if (panel->backlight.combination_mode) {
> +		u8 lbpc;
> +
> +		pci_read_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, &lbpc);
> +		val *= lbpc;
> +	}
> +
> +	return val;
> +}
> +
> +static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
> +		return 0;
> +
> +	return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
> +}
> +
> +static u32 bxt_get_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	return intel_de_read(dev_priv,
> +			     BXT_BLC_PWM_DUTY(panel->backlight.controller));
> +}
> +
> +static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +	struct pwm_state state;
> +
> +	pwm_get_state(panel->backlight.pwm, &state);
> +	return pwm_get_relative_duty_cycle(&state, 100);
> +}
> +
> +static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	u32 val = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, val | level);
> +}
> +
> +static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	u32 tmp;
> +
> +	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
> +	intel_de_write(dev_priv, BLC_PWM_CPU_CTL, tmp | level);
> +}
> +
> +static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 tmp, mask;
> +
> +	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
> +
> +	if (panel->backlight.combination_mode) {
> +		u8 lbpc;
> +
> +		lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1;
> +		level /= lbpc;
> +		pci_write_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, lbpc);
> +	}
> +
> +	if (DISPLAY_VER(dev_priv) == 4) {
> +		mask = BACKLIGHT_DUTY_CYCLE_MASK;
> +	} else {
> +		level <<= 1;
> +		mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
> +	}
> +
> +	tmp = intel_de_read(dev_priv, BLC_PWM_CTL) & ~mask;
> +	intel_de_write(dev_priv, BLC_PWM_CTL, tmp | level);
> +}
> +
> +static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
> +	u32 tmp;
> +
> +	tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
> +	intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), tmp | level);
> +}
> +
> +static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	intel_de_write(dev_priv,
> +		       BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
> +}
> +
> +static void ext_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
> +
> +	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
> +	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> +}
> +
> +static void
> +intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *i915 = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);
> +
> +	panel->backlight.funcs->set(conn_state, level);
> +}
> +
> +/* set backlight brightness to level in range [0..max], assuming hw min is
> + * respected.
> + */
> +void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
> +				    u32 user_level, u32 user_max)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 hw_level;
> +
> +	/*
> +	 * Lack of crtc may occur during driver init because
> +	 * connection_mutex isn't held across the entire backlight
> +	 * setup + modeset readout, and the BIOS can issue the
> +	 * requests at any time.
> +	 */
> +	if (!panel->backlight.present || !conn_state->crtc)
> +		return;
> +
> +	mutex_lock(&dev_priv->backlight_lock);
> +
> +	drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
> +
> +	hw_level = clamp_user_to_hw(connector, user_level, user_max);
> +	panel->backlight.level = hw_level;
> +
> +	if (panel->backlight.device)
> +		panel->backlight.device->props.brightness =
> +			scale_hw_to_user(connector,
> +					 panel->backlight.level,
> +					 panel->backlight.device->props.max_brightness);
> +
> +	if (panel->backlight.enabled)
> +		intel_panel_actually_set_backlight(conn_state, hw_level);
> +
> +	mutex_unlock(&dev_priv->backlight_lock);
> +}
> +
> +static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	u32 tmp;
> +
> +	intel_panel_set_pwm_level(old_conn_state, level);
> +
> +	/*
> +	 * Although we don't support or enable CPU PWM with LPT/SPT based
> +	 * systems, it may have been enabled prior to loading the
> +	 * driver. Disable to avoid warnings on LCPLL disable.
> +	 *
> +	 * This needs rework if we need to add support for CPU PWM on PCH split
> +	 * platforms.
> +	 */
> +	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> +	if (tmp & BLM_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "cpu backlight was enabled, disabling\n");
> +		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
> +			       tmp & ~BLM_PWM_ENABLE);
> +	}
> +
> +	tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
> +}
> +
> +static void pch_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	u32 tmp;
> +
> +	intel_panel_set_pwm_level(old_conn_state, val);
> +
> +	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> +	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
> +
> +	tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
> +}
> +
> +static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> +{
> +	intel_panel_set_pwm_level(old_conn_state, val);
> +}
> +
> +static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
> +	u32 tmp;
> +
> +	intel_panel_set_pwm_level(old_conn_state, val);
> +
> +	tmp = intel_de_read(dev_priv, BLC_PWM_CTL2);
> +	intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
> +}
> +
> +static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
> +	u32 tmp;
> +
> +	intel_panel_set_pwm_level(old_conn_state, val);
> +
> +	tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> +	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
> +		       tmp & ~BLM_PWM_ENABLE);
> +}
> +
> +static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 tmp;
> +
> +	intel_panel_set_pwm_level(old_conn_state, val);
> +
> +	tmp = intel_de_read(dev_priv,
> +			    BXT_BLC_PWM_CTL(panel->backlight.controller));
> +	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> +		       tmp & ~BXT_BLC_PWM_ENABLE);
> +
> +	if (panel->backlight.controller == 1) {
> +		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
> +		val &= ~UTIL_PIN_ENABLE;
> +		intel_de_write(dev_priv, UTIL_PIN_CTL, val);
> +	}
> +}
> +
> +static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 tmp;
> +
> +	intel_panel_set_pwm_level(old_conn_state, val);
> +
> +	tmp = intel_de_read(dev_priv,
> +			    BXT_BLC_PWM_CTL(panel->backlight.controller));
> +	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> +		       tmp & ~BXT_BLC_PWM_ENABLE);
> +}
> +
> +static void ext_pwm_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	panel->backlight.pwm_state.enabled = false;
> +	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> +}
> +
> +void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state)
> +{
> +	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	if (!panel->backlight.present)
> +		return;
> +
> +	/*
> +	 * Do not disable backlight on the vga_switcheroo path. When switching
> +	 * away from i915, the other client may depend on i915 to handle the
> +	 * backlight. This will leave the backlight on unnecessarily when
> +	 * another client is not activated.
> +	 */
> +	if (dev_priv->drm.switch_power_state == DRM_SWITCH_POWER_CHANGING) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "Skipping backlight disable on vga switch\n");
> +		return;
> +	}
> +
> +	mutex_lock(&dev_priv->backlight_lock);
> +
> +	if (panel->backlight.device)
> +		panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
> +	panel->backlight.enabled = false;
> +	panel->backlight.funcs->disable(old_conn_state, 0);
> +
> +	mutex_unlock(&dev_priv->backlight_lock);
> +}
> +
> +static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				 const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 pch_ctl1, pch_ctl2, schicken;
> +
> +	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
> +		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
> +		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> +	}
> +
> +	if (HAS_PCH_LPT(dev_priv)) {
> +		schicken = intel_de_read(dev_priv, SOUTH_CHICKEN2);
> +		if (panel->backlight.alternate_pwm_increment)
> +			schicken |= LPT_PWM_GRANULARITY;
> +		else
> +			schicken &= ~LPT_PWM_GRANULARITY;
> +		intel_de_write(dev_priv, SOUTH_CHICKEN2, schicken);
> +	} else {
> +		schicken = intel_de_read(dev_priv, SOUTH_CHICKEN1);
> +		if (panel->backlight.alternate_pwm_increment)
> +			schicken |= SPT_PWM_GRANULARITY;
> +		else
> +			schicken &= ~SPT_PWM_GRANULARITY;
> +		intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken);
> +	}
> +
> +	pch_ctl2 = panel->backlight.pwm_level_max << 16;
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
> +
> +	pch_ctl1 = 0;
> +	if (panel->backlight.active_low_pwm)
> +		pch_ctl1 |= BLM_PCH_POLARITY;
> +
> +	/* After LPT, override is the default. */
> +	if (HAS_PCH_LPT(dev_priv))
> +		pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
> +
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> +	intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
> +		       pch_ctl1 | BLM_PCH_PWM_ENABLE);
> +
> +	/* This won't stick until the above enable. */
> +	intel_panel_set_pwm_level(conn_state, level);
> +}
> +
> +static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				 const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> +	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
> +
> +	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> +	if (cpu_ctl2 & BLM_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "cpu backlight already enabled\n");
> +		cpu_ctl2 &= ~BLM_PWM_ENABLE;
> +		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
> +	}
> +
> +	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
> +		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
> +		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> +	}
> +
> +	if (cpu_transcoder == TRANSCODER_EDP)
> +		cpu_ctl2 = BLM_TRANSCODER_EDP;
> +	else
> +		cpu_ctl2 = BLM_PIPE(cpu_transcoder);
> +	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
> +	intel_de_posting_read(dev_priv, BLC_PWM_CPU_CTL2);
> +	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
> +
> +	/* This won't stick until the above enable. */
> +	intel_panel_set_pwm_level(conn_state, level);
> +
> +	pch_ctl2 = panel->backlight.pwm_level_max << 16;
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
> +
> +	pch_ctl1 = 0;
> +	if (panel->backlight.active_low_pwm)
> +		pch_ctl1 |= BLM_PCH_POLARITY;
> +
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> +	intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
> +		       pch_ctl1 | BLM_PCH_PWM_ENABLE);
> +}
> +
> +static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				  const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 ctl, freq;
> +
> +	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
> +	if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
> +		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> +		intel_de_write(dev_priv, BLC_PWM_CTL, 0);
> +	}
> +
> +	freq = panel->backlight.pwm_level_max;
> +	if (panel->backlight.combination_mode)
> +		freq /= 0xff;
> +
> +	ctl = freq << 17;
> +	if (panel->backlight.combination_mode)
> +		ctl |= BLM_LEGACY_MODE;
> +	if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
> +		ctl |= BLM_POLARITY_PNV;
> +
> +	intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
> +	intel_de_posting_read(dev_priv, BLC_PWM_CTL);
> +
> +	/* XXX: combine this into above write? */
> +	intel_panel_set_pwm_level(conn_state, level);
> +
> +	/*
> +	 * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
> +	 * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
> +	 * that has backlight.
> +	 */
> +	if (DISPLAY_VER(dev_priv) == 2)
> +		intel_de_write(dev_priv, BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
> +}
> +
> +static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				  const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
> +	u32 ctl, ctl2, freq;
> +
> +	ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
> +	if (ctl2 & BLM_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> +		ctl2 &= ~BLM_PWM_ENABLE;
> +		intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
> +	}
> +
> +	freq = panel->backlight.pwm_level_max;
> +	if (panel->backlight.combination_mode)
> +		freq /= 0xff;
> +
> +	ctl = freq << 16;
> +	intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
> +
> +	ctl2 = BLM_PIPE(pipe);
> +	if (panel->backlight.combination_mode)
> +		ctl2 |= BLM_COMBINATION_MODE;
> +	if (panel->backlight.active_low_pwm)
> +		ctl2 |= BLM_POLARITY_I965;
> +	intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
> +	intel_de_posting_read(dev_priv, BLC_PWM_CTL2);
> +	intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
> +
> +	intel_panel_set_pwm_level(conn_state, level);
> +}
> +
> +static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				 const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> +	u32 ctl, ctl2;
> +
> +	ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> +	if (ctl2 & BLM_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> +		ctl2 &= ~BLM_PWM_ENABLE;
> +		intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
> +	}
> +
> +	ctl = panel->backlight.pwm_level_max << 16;
> +	intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);
> +
> +	/* XXX: combine this into above write? */
> +	intel_panel_set_pwm_level(conn_state, level);
> +
> +	ctl2 = 0;
> +	if (panel->backlight.active_low_pwm)
> +		ctl2 |= BLM_POLARITY_I965;
> +	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
> +	intel_de_posting_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> +	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
> +		       ctl2 | BLM_PWM_ENABLE);
> +}
> +
> +static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				 const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> +	u32 pwm_ctl, val;
> +
> +	/* Controller 1 uses the utility pin. */
> +	if (panel->backlight.controller == 1) {
> +		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
> +		if (val & UTIL_PIN_ENABLE) {
> +			drm_dbg_kms(&dev_priv->drm,
> +				    "util pin already enabled\n");
> +			val &= ~UTIL_PIN_ENABLE;
> +			intel_de_write(dev_priv, UTIL_PIN_CTL, val);
> +		}
> +
> +		val = 0;
> +		if (panel->backlight.util_pin_active_low)
> +			val |= UTIL_PIN_POLARITY;
> +		intel_de_write(dev_priv, UTIL_PIN_CTL,
> +			       val | UTIL_PIN_PIPE(pipe) | UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
> +	}
> +
> +	pwm_ctl = intel_de_read(dev_priv,
> +				BXT_BLC_PWM_CTL(panel->backlight.controller));
> +	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> +		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
> +		intel_de_write(dev_priv,
> +			       BXT_BLC_PWM_CTL(panel->backlight.controller),
> +			       pwm_ctl);
> +	}
> +
> +	intel_de_write(dev_priv,
> +		       BXT_BLC_PWM_FREQ(panel->backlight.controller),
> +		       panel->backlight.pwm_level_max);
> +
> +	intel_panel_set_pwm_level(conn_state, level);
> +
> +	pwm_ctl = 0;
> +	if (panel->backlight.active_low_pwm)
> +		pwm_ctl |= BXT_BLC_PWM_POLARITY;
> +
> +	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> +		       pwm_ctl);
> +	intel_de_posting_read(dev_priv,
> +			      BXT_BLC_PWM_CTL(panel->backlight.controller));
> +	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> +		       pwm_ctl | BXT_BLC_PWM_ENABLE);
> +}
> +
> +static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				 const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 pwm_ctl;
> +
> +	pwm_ctl = intel_de_read(dev_priv,
> +				BXT_BLC_PWM_CTL(panel->backlight.controller));
> +	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
> +		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> +		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
> +		intel_de_write(dev_priv,
> +			       BXT_BLC_PWM_CTL(panel->backlight.controller),
> +			       pwm_ctl);
> +	}
> +
> +	intel_de_write(dev_priv,
> +		       BXT_BLC_PWM_FREQ(panel->backlight.controller),
> +		       panel->backlight.pwm_level_max);
> +
> +	intel_panel_set_pwm_level(conn_state, level);
> +
> +	pwm_ctl = 0;
> +	if (panel->backlight.active_low_pwm)
> +		pwm_ctl |= BXT_BLC_PWM_POLARITY;
> +
> +	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> +		       pwm_ctl);
> +	intel_de_posting_read(dev_priv,
> +			      BXT_BLC_PWM_CTL(panel->backlight.controller));
> +	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> +		       pwm_ctl | BXT_BLC_PWM_ENABLE);
> +}
> +
> +static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				     const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
> +	panel->backlight.pwm_state.enabled = true;
> +	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> +}
> +
> +static void __intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
> +					   const struct drm_connector_state *conn_state)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	WARN_ON(panel->backlight.max == 0);
> +
> +	if (panel->backlight.level <= panel->backlight.min) {
> +		panel->backlight.level = panel->backlight.max;
> +		if (panel->backlight.device)
> +			panel->backlight.device->props.brightness =
> +				scale_hw_to_user(connector,
> +						 panel->backlight.level,
> +						 panel->backlight.device->props.max_brightness);
> +	}
> +
> +	panel->backlight.funcs->enable(crtc_state, conn_state, panel->backlight.level);
> +	panel->backlight.enabled = true;
> +	if (panel->backlight.device)
> +		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
> +}
> +
> +void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				  const struct drm_connector_state *conn_state)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> +
> +	if (!panel->backlight.present)
> +		return;
> +
> +	drm_dbg_kms(&dev_priv->drm, "pipe %c\n", pipe_name(pipe));
> +
> +	mutex_lock(&dev_priv->backlight_lock);
> +
> +	__intel_panel_enable_backlight(crtc_state, conn_state);
> +
> +	mutex_unlock(&dev_priv->backlight_lock);
> +}
> +
> +#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
> +static u32 intel_panel_get_backlight(struct intel_connector *connector)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 val = 0;
> +
> +	mutex_lock(&dev_priv->backlight_lock);
> +
> +	if (panel->backlight.enabled)
> +		val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
> +
> +	mutex_unlock(&dev_priv->backlight_lock);
> +
> +	drm_dbg_kms(&dev_priv->drm, "get backlight PWM = %d\n", val);
> +	return val;
> +}
> +
> +/* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
> +static u32 scale_user_to_hw(struct intel_connector *connector,
> +			    u32 user_level, u32 user_max)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +
> +	return scale(user_level, 0, user_max,
> +		     panel->backlight.min, panel->backlight.max);
> +}
> +
> +/* set backlight brightness to level in range [0..max], scaling wrt hw min */
> +static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
> +				      u32 user_level, u32 user_max)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 hw_level;
> +
> +	if (!panel->backlight.present)
> +		return;
> +
> +	mutex_lock(&dev_priv->backlight_lock);
> +
> +	drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
> +
> +	hw_level = scale_user_to_hw(connector, user_level, user_max);
> +	panel->backlight.level = hw_level;
> +
> +	if (panel->backlight.enabled)
> +		intel_panel_actually_set_backlight(conn_state, hw_level);
> +
> +	mutex_unlock(&dev_priv->backlight_lock);
> +}
> +
> +static int intel_backlight_device_update_status(struct backlight_device *bd)
> +{
> +	struct intel_connector *connector = bl_get_data(bd);
> +	struct intel_panel *panel = &connector->panel;
> +	struct drm_device *dev = connector->base.dev;
> +
> +	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> +	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
> +		      bd->props.brightness, bd->props.max_brightness);
> +	intel_panel_set_backlight(connector->base.state, bd->props.brightness,
> +				  bd->props.max_brightness);
> +
> +	/*
> +	 * Allow flipping bl_power as a sub-state of enabled. Sadly the
> +	 * backlight class device does not make it easy to differentiate
> +	 * between callbacks for brightness and bl_power, so our backlight_power
> +	 * callback needs to take this into account.
> +	 */
> +	if (panel->backlight.enabled) {
> +		if (panel->backlight.power) {
> +			bool enable = bd->props.power == FB_BLANK_UNBLANK &&
> +				bd->props.brightness != 0;
> +			panel->backlight.power(connector, enable);
> +		}
> +	} else {
> +		bd->props.power = FB_BLANK_POWERDOWN;
> +	}
> +
> +	drm_modeset_unlock(&dev->mode_config.connection_mutex);
> +	return 0;
> +}
> +
> +static int intel_backlight_device_get_brightness(struct backlight_device *bd)
> +{
> +	struct intel_connector *connector = bl_get_data(bd);
> +	struct drm_device *dev = connector->base.dev;
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +	intel_wakeref_t wakeref;
> +	int ret = 0;
> +
> +	with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref) {
> +		u32 hw_level;
> +
> +		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> +
> +		hw_level = intel_panel_get_backlight(connector);
> +		ret = scale_hw_to_user(connector,
> +				       hw_level, bd->props.max_brightness);
> +
> +		drm_modeset_unlock(&dev->mode_config.connection_mutex);
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct backlight_ops intel_backlight_device_ops = {
> +	.update_status = intel_backlight_device_update_status,
> +	.get_brightness = intel_backlight_device_get_brightness,
> +};
> +
> +int intel_backlight_device_register(struct intel_connector *connector)
> +{
> +	struct drm_i915_private *i915 = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	struct backlight_properties props;
> +	struct backlight_device *bd;
> +	const char *name;
> +	int ret = 0;
> +
> +	if (WARN_ON(panel->backlight.device))
> +		return -ENODEV;
> +
> +	if (!panel->backlight.present)
> +		return 0;
> +
> +	WARN_ON(panel->backlight.max == 0);
> +
> +	memset(&props, 0, sizeof(props));
> +	props.type = BACKLIGHT_RAW;
> +
> +	/*
> +	 * Note: Everything should work even if the backlight device max
> +	 * presented to the userspace is arbitrarily chosen.
> +	 */
> +	props.max_brightness = panel->backlight.max;
> +	props.brightness = scale_hw_to_user(connector,
> +					    panel->backlight.level,
> +					    props.max_brightness);
> +
> +	if (panel->backlight.enabled)
> +		props.power = FB_BLANK_UNBLANK;
> +	else
> +		props.power = FB_BLANK_POWERDOWN;
> +
> +	name = kstrdup("intel_backlight", GFP_KERNEL);
> +	if (!name)
> +		return -ENOMEM;
> +
> +	bd = backlight_device_register(name, connector->base.kdev, connector,
> +				       &intel_backlight_device_ops, &props);
> +
> +	/*
> +	 * Using the same name independent of the drm device or connector
> +	 * prevents registration of multiple backlight devices in the
> +	 * driver. However, we need to use the default name for backward
> +	 * compatibility. Use unique names for subsequent backlight devices as a
> +	 * fallback when the default name already exists.
> +	 */
> +	if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) {
> +		kfree(name);
> +		name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
> +				 i915->drm.primary->index, connector->base.name);
> +		if (!name)
> +			return -ENOMEM;
> +
> +		bd = backlight_device_register(name, connector->base.kdev, connector,
> +					       &intel_backlight_device_ops, &props);
> +	}
> +
> +	if (IS_ERR(bd)) {
> +		drm_err(&i915->drm,
> +			"[CONNECTOR:%d:%s] backlight device %s register failed: %ld\n",
> +			connector->base.base.id, connector->base.name, name, PTR_ERR(bd));
> +		ret = PTR_ERR(bd);
> +		goto out;
> +	}
> +
> +	panel->backlight.device = bd;
> +
> +	drm_dbg_kms(&i915->drm,
> +		    "[CONNECTOR:%d:%s] backlight device %s registered\n",
> +		    connector->base.base.id, connector->base.name, name);
> +
> +out:
> +	kfree(name);
> +
> +	return ret;
> +}
> +
> +void intel_backlight_device_unregister(struct intel_connector *connector)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +
> +	if (panel->backlight.device) {
> +		backlight_device_unregister(panel->backlight.device);
> +		panel->backlight.device = NULL;
> +	}
> +}
> +#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
> +
> +/*
> + * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
> + *      PWM increment = 1
> + */
> +static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
> +				 pwm_freq_hz);
> +}
> +
> +/*
> + * BXT: PWM clock frequency = 19.2 MHz.
> + */
> +static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
> +}
> +
> +/*
> + * SPT: This value represents the period of the PWM stream in clock periods
> + * multiplied by 16 (default increment) or 128 (alternate increment selected in
> + * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
> + */
> +static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +	u32 mul;
> +
> +	if (panel->backlight.alternate_pwm_increment)
> +		mul = 128;
> +	else
> +		mul = 16;
> +
> +	return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
> +}
> +
> +/*
> + * LPT: This value represents the period of the PWM stream in clock periods
> + * multiplied by 128 (default increment) or 16 (alternate increment, selected in
> + * LPT SOUTH_CHICKEN2 register bit 5).
> + */
> +static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 mul, clock;
> +
> +	if (panel->backlight.alternate_pwm_increment)
> +		mul = 16;
> +	else
> +		mul = 128;
> +
> +	if (HAS_PCH_LPT_H(dev_priv))
> +		clock = MHz(135); /* LPT:H */
> +	else
> +		clock = MHz(24); /* LPT:LP */
> +
> +	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
> +}
> +
> +/*
> + * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
> + * display raw clocks multiplied by 128.
> + */
> +static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
> +				 pwm_freq_hz * 128);
> +}
> +
> +/*
> + * Gen2: This field determines the number of time base events (display core
> + * clock frequency/32) in total for a complete cycle of modulated backlight
> + * control.
> + *
> + * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
> + * divided by 32.
> + */
> +static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	int clock;
> +
> +	if (IS_PINEVIEW(dev_priv))
> +		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
> +	else
> +		clock = KHz(dev_priv->cdclk.hw.cdclk);
> +
> +	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
> +}
> +
> +/*
> + * Gen4: This value represents the period of the PWM stream in display core
> + * clocks ([DevCTG] HRAW clocks) multiplied by 128.
> + *
> + */
> +static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	int clock;
> +
> +	if (IS_G4X(dev_priv))
> +		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
> +	else
> +		clock = KHz(dev_priv->cdclk.hw.cdclk);
> +
> +	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
> +}
> +
> +/*
> + * VLV: This value represents the period of the PWM stream in display core
> + * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
> + * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
> + */
> +static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	int mul, clock;
> +
> +	if ((intel_de_read(dev_priv, CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
> +		if (IS_CHERRYVIEW(dev_priv))
> +			clock = KHz(19200);
> +		else
> +			clock = MHz(25);
> +		mul = 16;
> +	} else {
> +		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
> +		mul = 128;
> +	}
> +
> +	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
> +}
> +
> +static u16 get_vbt_pwm_freq(struct drm_i915_private *dev_priv)
> +{
> +	u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz;
> +
> +	if (pwm_freq_hz) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "VBT defined backlight frequency %u Hz\n",
> +			    pwm_freq_hz);
> +	} else {
> +		pwm_freq_hz = 200;
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "default backlight frequency %u Hz\n",
> +			    pwm_freq_hz);
> +	}
> +
> +	return pwm_freq_hz;
> +}
> +
> +static u32 get_backlight_max_vbt(struct intel_connector *connector)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv);
> +	u32 pwm;
> +
> +	if (!panel->backlight.pwm_funcs->hz_to_pwm) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "backlight frequency conversion not supported\n");
> +		return 0;
> +	}
> +
> +	pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz);
> +	if (!pwm) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "backlight frequency conversion failed\n");
> +		return 0;
> +	}
> +
> +	return pwm;
> +}
> +
> +/*
> + * Note: The setup hooks can't assume pipe is set!
> + */
> +static u32 get_backlight_min_vbt(struct intel_connector *connector)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	int min;
> +
> +	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
> +
> +	/*
> +	 * XXX: If the vbt value is 255, it makes min equal to max, which leads
> +	 * to problems. There are such machines out there. Either our
> +	 * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
> +	 * against this by letting the minimum be at most (arbitrarily chosen)
> +	 * 25% of the max.
> +	 */
> +	min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
> +	if (min != dev_priv->vbt.backlight.min_brightness) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "clamping VBT min backlight %d/255 to %d/255\n",
> +			    dev_priv->vbt.backlight.min_brightness, min);
> +	}
> +
> +	/* vbt value is a coefficient in range [0..255] */
> +	return scale(min, 0, 255, 0, panel->backlight.pwm_level_max);
> +}
> +
> +static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
> +	bool alt, cpu_mode;
> +
> +	if (HAS_PCH_LPT(dev_priv))
> +		alt = intel_de_read(dev_priv, SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY;
> +	else
> +		alt = intel_de_read(dev_priv, SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY;
> +	panel->backlight.alternate_pwm_increment = alt;
> +
> +	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
> +
> +	pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
> +	panel->backlight.pwm_level_max = pch_ctl2 >> 16;
> +
> +	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;
> +
> +	cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) &&
> +		   !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
> +		   (cpu_ctl2 & BLM_PWM_ENABLE);
> +
> +	if (cpu_mode) {
> +		val = pch_get_backlight(connector, unused);
> +
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "CPU backlight register was enabled, switching to PCH override\n");
> +
> +		/* Write converted CPU PWM value to PCH override register */
> +		lpt_set_backlight(connector->base.state, val);
> +		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
> +			       pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE);
> +
> +		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
> +			       cpu_ctl2 & ~BLM_PWM_ENABLE);
> +	}
> +
> +	return 0;
> +}
> +
> +static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
> +
> +	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> +	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
> +
> +	pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
> +	panel->backlight.pwm_level_max = pch_ctl2 >> 16;
> +
> +	if (!panel->backlight.pwm_level_max)
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> +	panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
> +		(pch_ctl1 & BLM_PCH_PWM_ENABLE);
> +
> +	return 0;
> +}
> +
> +static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 ctl, val;
> +
> +	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
> +
> +	if (DISPLAY_VER(dev_priv) == 2 || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
> +		panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
> +
> +	if (IS_PINEVIEW(dev_priv))
> +		panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
> +
> +	panel->backlight.pwm_level_max = ctl >> 17;
> +
> +	if (!panel->backlight.pwm_level_max) {
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +		panel->backlight.pwm_level_max >>= 1;
> +	}
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	if (panel->backlight.combination_mode)
> +		panel->backlight.pwm_level_max *= 0xff;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	val = i9xx_get_backlight(connector, unused);
> +	val = intel_panel_invert_pwm_level(connector, val);
> +	val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
> +
> +	panel->backlight.pwm_enabled = val != 0;
> +
> +	return 0;
> +}
> +
> +static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 ctl, ctl2;
> +
> +	ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
> +	panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
> +	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
> +
> +	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
> +	panel->backlight.pwm_level_max = ctl >> 16;
> +
> +	if (!panel->backlight.pwm_level_max)
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	if (panel->backlight.combination_mode)
> +		panel->backlight.pwm_level_max *= 0xff;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
> +
> +	return 0;
> +}
> +
> +static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 ctl, ctl2;
> +
> +	if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
> +		return -ENODEV;
> +
> +	ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> +	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
> +
> +	ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe));
> +	panel->backlight.pwm_level_max = ctl >> 16;
> +
> +	if (!panel->backlight.pwm_level_max)
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
> +
> +	return 0;
> +}
> +
> +static int
> +bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 pwm_ctl, val;
> +
> +	panel->backlight.controller = dev_priv->vbt.backlight.controller;
> +
> +	pwm_ctl = intel_de_read(dev_priv,
> +				BXT_BLC_PWM_CTL(panel->backlight.controller));
> +
> +	/* Controller 1 uses the utility pin. */
> +	if (panel->backlight.controller == 1) {
> +		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
> +		panel->backlight.util_pin_active_low =
> +					val & UTIL_PIN_POLARITY;
> +	}
> +
> +	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
> +	panel->backlight.pwm_level_max =
> +		intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
> +
> +	if (!panel->backlight.pwm_level_max)
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
> +
> +	return 0;
> +}
> +
> +static int
> +cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +	u32 pwm_ctl;
> +
> +	/*
> +	 * CNP has the BXT implementation of backlight, but with only one
> +	 * controller. TODO: ICP has multiple controllers but we only use
> +	 * controller 0 for now.
> +	 */
> +	panel->backlight.controller = 0;
> +
> +	pwm_ctl = intel_de_read(dev_priv,
> +				BXT_BLC_PWM_CTL(panel->backlight.controller));
> +
> +	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
> +	panel->backlight.pwm_level_max =
> +		intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
> +
> +	if (!panel->backlight.pwm_level_max)
> +		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> +
> +	if (!panel->backlight.pwm_level_max)
> +		return -ENODEV;
> +
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
> +
> +	return 0;
> +}
> +
> +static int ext_pwm_setup_backlight(struct intel_connector *connector,
> +				   enum pipe pipe)
> +{
> +	struct drm_device *dev = connector->base.dev;
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +	struct intel_panel *panel = &connector->panel;
> +	const char *desc;
> +	u32 level;
> +
> +	/* Get the right PWM chip for DSI backlight according to VBT */
> +	if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
> +		panel->backlight.pwm = pwm_get(dev->dev, "pwm_pmic_backlight");
> +		desc = "PMIC";
> +	} else {
> +		panel->backlight.pwm = pwm_get(dev->dev, "pwm_soc_backlight");
> +		desc = "SoC";
> +	}
> +
> +	if (IS_ERR(panel->backlight.pwm)) {
> +		drm_err(&dev_priv->drm, "Failed to get the %s PWM chip\n",
> +			desc);
> +		panel->backlight.pwm = NULL;
> +		return -ENODEV;
> +	}
> +
> +	panel->backlight.pwm_level_max = 100; /* 100% */
> +	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> +
> +	if (pwm_is_enabled(panel->backlight.pwm)) {
> +		/* PWM is already enabled, use existing settings */
> +		pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> +
> +		level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state,
> +						    100);
> +		level = intel_panel_invert_pwm_level(connector, level);
> +		panel->backlight.pwm_enabled = true;
> +
> +		drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n",
> +			    NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period,
> +			    get_vbt_pwm_freq(dev_priv), level);
> +	} else {
> +		/* Set period from VBT frequency, leave other settings at 0. */
> +		panel->backlight.pwm_state.period =
> +			NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv);
> +	}
> +
> +	drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",
> +		 desc);
> +	return 0;
> +}
> +
> +static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	panel->backlight.pwm_funcs->set(conn_state,
> +				       intel_panel_invert_pwm_level(connector, level));
> +}
> +
> +static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +
> +	return intel_panel_invert_pwm_level(connector,
> +					    panel->backlight.pwm_funcs->get(connector, pipe));
> +}
> +
> +static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				       const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	panel->backlight.pwm_funcs->enable(crtc_state, conn_state,
> +					   intel_panel_invert_pwm_level(connector, level));
> +}
> +
> +static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	panel->backlight.pwm_funcs->disable(conn_state,
> +					    intel_panel_invert_pwm_level(connector, level));
> +}
> +
> +static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe)
> +{
> +	struct intel_panel *panel = &connector->panel;
> +	int ret = panel->backlight.pwm_funcs->setup(connector, pipe);
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	panel->backlight.min = panel->backlight.pwm_level_min;
> +	panel->backlight.max = panel->backlight.pwm_level_max;
> +	panel->backlight.level = intel_pwm_get_backlight(connector, pipe);
> +	panel->backlight.enabled = panel->backlight.pwm_enabled;
> +
> +	return 0;
> +}
> +
> +void intel_panel_update_backlight(struct intel_atomic_state *state,
> +				  struct intel_encoder *encoder,
> +				  const struct intel_crtc_state *crtc_state,
> +				  const struct drm_connector_state *conn_state)
> +{
> +	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +	struct intel_panel *panel = &connector->panel;
> +
> +	if (!panel->backlight.present)
> +		return;
> +
> +	mutex_lock(&dev_priv->backlight_lock);
> +	if (!panel->backlight.enabled)
> +		__intel_panel_enable_backlight(crtc_state, conn_state);
> +
> +	mutex_unlock(&dev_priv->backlight_lock);
> +}
> +
> +int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(connector->dev);
> +	struct intel_connector *intel_connector = to_intel_connector(connector);
> +	struct intel_panel *panel = &intel_connector->panel;
> +	int ret;
> +
> +	if (!dev_priv->vbt.backlight.present) {
> +		if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
> +			drm_dbg_kms(&dev_priv->drm,
> +				    "no backlight present per VBT, but present per quirk\n");
> +		} else {
> +			drm_dbg_kms(&dev_priv->drm,
> +				    "no backlight present per VBT\n");
> +			return 0;
> +		}
> +	}
> +
> +	/* ensure intel_panel has been initialized first */
> +	if (drm_WARN_ON(&dev_priv->drm, !panel->backlight.funcs))
> +		return -ENODEV;
> +
> +	/* set level and max in panel struct */
> +	mutex_lock(&dev_priv->backlight_lock);
> +	ret = panel->backlight.funcs->setup(intel_connector, pipe);
> +	mutex_unlock(&dev_priv->backlight_lock);
> +
> +	if (ret) {
> +		drm_dbg_kms(&dev_priv->drm,
> +			    "failed to setup backlight for connector %s\n",
> +			    connector->name);
> +		return ret;
> +	}
> +
> +	panel->backlight.present = true;
> +
> +	drm_dbg_kms(&dev_priv->drm,
> +		    "Connector %s backlight initialized, %s, brightness %u/%u\n",
> +		    connector->name,
> +		    enableddisabled(panel->backlight.enabled),
> +		    panel->backlight.level, panel->backlight.max);
> +
> +	return 0;
> +}
> +
> +void intel_panel_destroy_backlight(struct intel_panel *panel)
> +{
> +	/* dispose of the pwm */
> +	if (panel->backlight.pwm)
> +		pwm_put(panel->backlight.pwm);
> +
> +	panel->backlight.present = false;
> +}
> +
> +static const struct intel_panel_bl_funcs bxt_pwm_funcs = {
> +	.setup = bxt_setup_backlight,
> +	.enable = bxt_enable_backlight,
> +	.disable = bxt_disable_backlight,
> +	.set = bxt_set_backlight,
> +	.get = bxt_get_backlight,
> +	.hz_to_pwm = bxt_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs cnp_pwm_funcs = {
> +	.setup = cnp_setup_backlight,
> +	.enable = cnp_enable_backlight,
> +	.disable = cnp_disable_backlight,
> +	.set = bxt_set_backlight,
> +	.get = bxt_get_backlight,
> +	.hz_to_pwm = cnp_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs lpt_pwm_funcs = {
> +	.setup = lpt_setup_backlight,
> +	.enable = lpt_enable_backlight,
> +	.disable = lpt_disable_backlight,
> +	.set = lpt_set_backlight,
> +	.get = lpt_get_backlight,
> +	.hz_to_pwm = lpt_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs spt_pwm_funcs = {
> +	.setup = lpt_setup_backlight,
> +	.enable = lpt_enable_backlight,
> +	.disable = lpt_disable_backlight,
> +	.set = lpt_set_backlight,
> +	.get = lpt_get_backlight,
> +	.hz_to_pwm = spt_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs pch_pwm_funcs = {
> +	.setup = pch_setup_backlight,
> +	.enable = pch_enable_backlight,
> +	.disable = pch_disable_backlight,
> +	.set = pch_set_backlight,
> +	.get = pch_get_backlight,
> +	.hz_to_pwm = pch_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs ext_pwm_funcs = {
> +	.setup = ext_pwm_setup_backlight,
> +	.enable = ext_pwm_enable_backlight,
> +	.disable = ext_pwm_disable_backlight,
> +	.set = ext_pwm_set_backlight,
> +	.get = ext_pwm_get_backlight,
> +};
> +
> +static const struct intel_panel_bl_funcs vlv_pwm_funcs = {
> +	.setup = vlv_setup_backlight,
> +	.enable = vlv_enable_backlight,
> +	.disable = vlv_disable_backlight,
> +	.set = vlv_set_backlight,
> +	.get = vlv_get_backlight,
> +	.hz_to_pwm = vlv_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs i965_pwm_funcs = {
> +	.setup = i965_setup_backlight,
> +	.enable = i965_enable_backlight,
> +	.disable = i965_disable_backlight,
> +	.set = i9xx_set_backlight,
> +	.get = i9xx_get_backlight,
> +	.hz_to_pwm = i965_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs i9xx_pwm_funcs = {
> +	.setup = i9xx_setup_backlight,
> +	.enable = i9xx_enable_backlight,
> +	.disable = i9xx_disable_backlight,
> +	.set = i9xx_set_backlight,
> +	.get = i9xx_get_backlight,
> +	.hz_to_pwm = i9xx_hz_to_pwm,
> +};
> +
> +static const struct intel_panel_bl_funcs pwm_bl_funcs = {
> +	.setup = intel_pwm_setup_backlight,
> +	.enable = intel_pwm_enable_backlight,
> +	.disable = intel_pwm_disable_backlight,
> +	.set = intel_pwm_set_backlight,
> +	.get = intel_pwm_get_backlight,
> +};
> +
> +/* Set up chip specific backlight functions */
> +void
> +intel_panel_init_backlight_funcs(struct intel_panel *panel)
> +{
> +	struct intel_connector *connector =
> +		container_of(panel, struct intel_connector, panel);
> +	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> +
> +	if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
> +	    intel_dsi_dcs_init_backlight_funcs(connector) == 0)
> +		return;
> +
> +	if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
> +		panel->backlight.pwm_funcs = &bxt_pwm_funcs;
> +	} else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) {
> +		panel->backlight.pwm_funcs = &cnp_pwm_funcs;
> +	} else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) {
> +		if (HAS_PCH_LPT(dev_priv))
> +			panel->backlight.pwm_funcs = &lpt_pwm_funcs;
> +		else
> +			panel->backlight.pwm_funcs = &spt_pwm_funcs;
> +	} else if (HAS_PCH_SPLIT(dev_priv)) {
> +		panel->backlight.pwm_funcs = &pch_pwm_funcs;
> +	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
> +		if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
> +			panel->backlight.pwm_funcs = &ext_pwm_funcs;
> +		} else {
> +			panel->backlight.pwm_funcs = &vlv_pwm_funcs;
> +		}
> +	} else if (DISPLAY_VER(dev_priv) == 4) {
> +		panel->backlight.pwm_funcs = &i965_pwm_funcs;
> +	} else {
> +		panel->backlight.pwm_funcs = &i9xx_pwm_funcs;
> +	}
> +
> +	if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP &&
> +	    intel_dp_aux_init_backlight_funcs(connector) == 0)
> +		return;
> +
> +	/* We're using a standard PWM backlight interface */
> +	panel->backlight.funcs = &pwm_bl_funcs;
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_backlight.h b/drivers/gpu/drm/i915/display/intel_backlight.h
> new file mode 100644
> index 0000000000000..282020cb47d5b
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/display/intel_backlight.h
> @@ -0,0 +1,51 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright © 2021 Intel Corporation
> + */
> +
> +#ifndef __INTEL_BACKLIGHT_H__
> +#define __INTEL_BACKLIGHT_H__
> +
> +#include <linux/types.h>
> +
> +struct drm_connector;
> +struct drm_connector_state;
> +struct intel_atomic_state;
> +struct intel_connector;
> +struct intel_crtc_state;
> +struct intel_encoder;
> +struct intel_panel;
> +enum pipe;
> +
> +void intel_panel_init_backlight_funcs(struct intel_panel *panel);
> +void intel_panel_destroy_backlight(struct intel_panel *panel);
> +void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
> +				    u32 level, u32 max);
> +int intel_panel_setup_backlight(struct drm_connector *connector,
> +				enum pipe pipe);
> +void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
> +				  const struct drm_connector_state *conn_state);
> +void intel_panel_update_backlight(struct intel_atomic_state *state,
> +				  struct intel_encoder *encoder,
> +				  const struct intel_crtc_state *crtc_state,
> +				  const struct drm_connector_state *conn_state);
> +void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state);
> +void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 level);
> +u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 level);
> +u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 level);
> +u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val);
> +
> +#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
> +int intel_backlight_device_register(struct intel_connector *connector);
> +void intel_backlight_device_unregister(struct intel_connector *connector);
> +#else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
> +static inline int intel_backlight_device_register(struct intel_connector *connector)
> +{
> +	return 0;
> +}
> +static inline void intel_backlight_device_unregister(struct intel_connector *connector)
> +{
> +}
> +#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
> +
> +#endif /* __INTEL_BACKLIGHT_H__ */
> diff --git a/drivers/gpu/drm/i915/display/intel_connector.c b/drivers/gpu/drm/i915/display/intel_connector.c
> index 9bed1ccecea0d..4f49d782eca23 100644
> --- a/drivers/gpu/drm/i915/display/intel_connector.c
> +++ b/drivers/gpu/drm/i915/display/intel_connector.c
> @@ -29,13 +29,13 @@
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_edid.h>
>  
> -#include "display/intel_panel.h"
> -
>  #include "i915_drv.h"
> +#include "intel_backlight.h"
>  #include "intel_connector.h"
>  #include "intel_display_debugfs.h"
>  #include "intel_display_types.h"
>  #include "intel_hdcp.h"
> +#include "intel_panel.h"
>  
>  int intel_connector_init(struct intel_connector *connector)
>  {
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index f61901e26409e..68489c7298302 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -29,6 +29,7 @@
>  
>  #include "i915_drv.h"
>  #include "intel_audio.h"
> +#include "intel_backlight.h"
>  #include "intel_combo_phy.h"
>  #include "intel_connector.h"
>  #include "intel_crtc.h"
> @@ -49,7 +50,6 @@
>  #include "intel_hdmi.h"
>  #include "intel_hotplug.h"
>  #include "intel_lspcon.h"
> -#include "intel_panel.h"
>  #include "intel_pps.h"
>  #include "intel_psr.h"
>  #include "intel_snps_phy.h"
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 631cf7d4323c8..f87e4d510ea5e 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -45,6 +45,7 @@
>  #include "i915_drv.h"
>  #include "intel_atomic.h"
>  #include "intel_audio.h"
> +#include "intel_backlight.h"
>  #include "intel_connector.h"
>  #include "intel_ddi.h"
>  #include "intel_de.h"
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> index e7b90863aa43d..0a77f0e48aa11 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c
> @@ -34,10 +34,10 @@
>   * for some reason.
>   */
>  
> +#include "intel_backlight.h"
>  #include "intel_display_types.h"
>  #include "intel_dp.h"
>  #include "intel_dp_aux_backlight.h"
> -#include "intel_panel.h"
>  
>  /* TODO:
>   * Implement HDR, right now we just implement the bare minimum to bring us back into SDR mode so we
> diff --git a/drivers/gpu/drm/i915/display/intel_lvds.c b/drivers/gpu/drm/i915/display/intel_lvds.c
> index e0381b0fce914..8f5741ebd58dd 100644
> --- a/drivers/gpu/drm/i915/display/intel_lvds.c
> +++ b/drivers/gpu/drm/i915/display/intel_lvds.c
> @@ -40,6 +40,7 @@
>  
>  #include "i915_drv.h"
>  #include "intel_atomic.h"
> +#include "intel_backlight.h"
>  #include "intel_connector.h"
>  #include "intel_de.h"
>  #include "intel_display_types.h"
> diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c b/drivers/gpu/drm/i915/display/intel_opregion.c
> index f7f49b69830fa..aad5c1cd3898e 100644
> --- a/drivers/gpu/drm/i915/display/intel_opregion.c
> +++ b/drivers/gpu/drm/i915/display/intel_opregion.c
> @@ -30,10 +30,9 @@
>  #include <linux/firmware.h>
>  #include <acpi/video.h>
>  
> -#include "display/intel_panel.h"
> -
>  #include "i915_drv.h"
>  #include "intel_acpi.h"
> +#include "intel_backlight.h"
>  #include "intel_display_types.h"
>  #include "intel_opregion.h"
>  
> diff --git a/drivers/gpu/drm/i915/display/intel_panel.c b/drivers/gpu/drm/i915/display/intel_panel.c
> index 7d7a60b4d2de7..ad54767440c15 100644
> --- a/drivers/gpu/drm/i915/display/intel_panel.c
> +++ b/drivers/gpu/drm/i915/display/intel_panel.c
> @@ -28,17 +28,13 @@
>   *      Chris Wilson <chris@chris-wilson.co.uk>
>   */
>  
> -#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> -
>  #include <linux/kernel.h>
> -#include <linux/moduleparam.h>
>  #include <linux/pwm.h>
>  
> +#include "intel_backlight.h"
>  #include "intel_connector.h"
>  #include "intel_de.h"
>  #include "intel_display_types.h"
> -#include "intel_dp_aux_backlight.h"
> -#include "intel_dsi_dcs_backlight.h"
>  #include "intel_panel.h"
>  
>  void
> @@ -456,1767 +452,6 @@ int intel_gmch_panel_fitting(struct intel_crtc_state *crtc_state,
>  	return 0;
>  }
>  
> -/**
> - * scale - scale values from one range to another
> - * @source_val: value in range [@source_min..@source_max]
> - * @source_min: minimum legal value for @source_val
> - * @source_max: maximum legal value for @source_val
> - * @target_min: corresponding target value for @source_min
> - * @target_max: corresponding target value for @source_max
> - *
> - * Return @source_val in range [@source_min..@source_max] scaled to range
> - * [@target_min..@target_max].
> - */
> -static u32 scale(u32 source_val,
> -		 u32 source_min, u32 source_max,
> -		 u32 target_min, u32 target_max)
> -{
> -	u64 target_val;
> -
> -	WARN_ON(source_min > source_max);
> -	WARN_ON(target_min > target_max);
> -
> -	/* defensive */
> -	source_val = clamp(source_val, source_min, source_max);
> -
> -	/* avoid overflows */
> -	target_val = mul_u32_u32(source_val - source_min,
> -				 target_max - target_min);
> -	target_val = DIV_ROUND_CLOSEST_ULL(target_val, source_max - source_min);
> -	target_val += target_min;
> -
> -	return target_val;
> -}
> -
> -/* Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
> - * to [hw_min..hw_max]. */
> -static u32 clamp_user_to_hw(struct intel_connector *connector,
> -			    u32 user_level, u32 user_max)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -	u32 hw_level;
> -
> -	hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
> -	hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
> -
> -	return hw_level;
> -}
> -
> -/* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
> -static u32 scale_hw_to_user(struct intel_connector *connector,
> -			    u32 hw_level, u32 user_max)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -
> -	return scale(hw_level, panel->backlight.min, panel->backlight.max,
> -		     0, user_max);
> -}
> -
> -u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
> -
> -	if (dev_priv->params.invert_brightness < 0)
> -		return val;
> -
> -	if (dev_priv->params.invert_brightness > 0 ||
> -	    dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
> -		return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min;
> -	}
> -
> -	return val;
> -}
> -
> -void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 val)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *i915 = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val);
> -	panel->backlight.pwm_funcs->set(conn_state, val);
> -}
> -
> -u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 val)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	drm_WARN_ON_ONCE(&dev_priv->drm,
> -			 panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
> -
> -	val = scale(val, panel->backlight.min, panel->backlight.max,
> -		    panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
> -
> -	return intel_panel_invert_pwm_level(connector, val);
> -}
> -
> -u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	drm_WARN_ON_ONCE(&dev_priv->drm,
> -			 panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
> -
> -	if (dev_priv->params.invert_brightness > 0 ||
> -	    (dev_priv->params.invert_brightness == 0 && dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS))
> -		val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min);
> -
> -	return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max,
> -		     panel->backlight.min, panel->backlight.max);
> -}
> -
> -static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
> -}
> -
> -static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> -}
> -
> -static u32 i9xx_get_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 val;
> -
> -	val = intel_de_read(dev_priv, BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> -	if (DISPLAY_VER(dev_priv) < 4)
> -		val >>= 1;
> -
> -	if (panel->backlight.combination_mode) {
> -		u8 lbpc;
> -
> -		pci_read_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, &lbpc);
> -		val *= lbpc;
> -	}
> -
> -	return val;
> -}
> -
> -static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
> -		return 0;
> -
> -	return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
> -}
> -
> -static u32 bxt_get_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	return intel_de_read(dev_priv,
> -			     BXT_BLC_PWM_DUTY(panel->backlight.controller));
> -}
> -
> -static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -	struct pwm_state state;
> -
> -	pwm_get_state(panel->backlight.pwm, &state);
> -	return pwm_get_relative_duty_cycle(&state, 100);
> -}
> -
> -static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	u32 val = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, val | level);
> -}
> -
> -static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	u32 tmp;
> -
> -	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
> -	intel_de_write(dev_priv, BLC_PWM_CPU_CTL, tmp | level);
> -}
> -
> -static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 tmp, mask;
> -
> -	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
> -
> -	if (panel->backlight.combination_mode) {
> -		u8 lbpc;
> -
> -		lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1;
> -		level /= lbpc;
> -		pci_write_config_byte(to_pci_dev(dev_priv->drm.dev), LBPC, lbpc);
> -	}
> -
> -	if (DISPLAY_VER(dev_priv) == 4) {
> -		mask = BACKLIGHT_DUTY_CYCLE_MASK;
> -	} else {
> -		level <<= 1;
> -		mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
> -	}
> -
> -	tmp = intel_de_read(dev_priv, BLC_PWM_CTL) & ~mask;
> -	intel_de_write(dev_priv, BLC_PWM_CTL, tmp | level);
> -}
> -
> -static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
> -	u32 tmp;
> -
> -	tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
> -	intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), tmp | level);
> -}
> -
> -static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	intel_de_write(dev_priv,
> -		       BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
> -}
> -
> -static void ext_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
> -
> -	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
> -	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> -}
> -
> -static void
> -intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *i915 = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);
> -
> -	panel->backlight.funcs->set(conn_state, level);
> -}
> -
> -/* set backlight brightness to level in range [0..max], assuming hw min is
> - * respected.
> - */
> -void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
> -				    u32 user_level, u32 user_max)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 hw_level;
> -
> -	/*
> -	 * Lack of crtc may occur during driver init because
> -	 * connection_mutex isn't held across the entire backlight
> -	 * setup + modeset readout, and the BIOS can issue the
> -	 * requests at any time.
> -	 */
> -	if (!panel->backlight.present || !conn_state->crtc)
> -		return;
> -
> -	mutex_lock(&dev_priv->backlight_lock);
> -
> -	drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
> -
> -	hw_level = clamp_user_to_hw(connector, user_level, user_max);
> -	panel->backlight.level = hw_level;
> -
> -	if (panel->backlight.device)
> -		panel->backlight.device->props.brightness =
> -			scale_hw_to_user(connector,
> -					 panel->backlight.level,
> -					 panel->backlight.device->props.max_brightness);
> -
> -	if (panel->backlight.enabled)
> -		intel_panel_actually_set_backlight(conn_state, hw_level);
> -
> -	mutex_unlock(&dev_priv->backlight_lock);
> -}
> -
> -static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	u32 tmp;
> -
> -	intel_panel_set_pwm_level(old_conn_state, level);
> -
> -	/*
> -	 * Although we don't support or enable CPU PWM with LPT/SPT based
> -	 * systems, it may have been enabled prior to loading the
> -	 * driver. Disable to avoid warnings on LCPLL disable.
> -	 *
> -	 * This needs rework if we need to add support for CPU PWM on PCH split
> -	 * platforms.
> -	 */
> -	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> -	if (tmp & BLM_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "cpu backlight was enabled, disabling\n");
> -		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
> -			       tmp & ~BLM_PWM_ENABLE);
> -	}
> -
> -	tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
> -}
> -
> -static void pch_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	u32 tmp;
> -
> -	intel_panel_set_pwm_level(old_conn_state, val);
> -
> -	tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> -	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
> -
> -	tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
> -}
> -
> -static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> -{
> -	intel_panel_set_pwm_level(old_conn_state, val);
> -}
> -
> -static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
> -	u32 tmp;
> -
> -	intel_panel_set_pwm_level(old_conn_state, val);
> -
> -	tmp = intel_de_read(dev_priv, BLC_PWM_CTL2);
> -	intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
> -}
> -
> -static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
> -	u32 tmp;
> -
> -	intel_panel_set_pwm_level(old_conn_state, val);
> -
> -	tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> -	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
> -		       tmp & ~BLM_PWM_ENABLE);
> -}
> -
> -static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 tmp;
> -
> -	intel_panel_set_pwm_level(old_conn_state, val);
> -
> -	tmp = intel_de_read(dev_priv,
> -			    BXT_BLC_PWM_CTL(panel->backlight.controller));
> -	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> -		       tmp & ~BXT_BLC_PWM_ENABLE);
> -
> -	if (panel->backlight.controller == 1) {
> -		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
> -		val &= ~UTIL_PIN_ENABLE;
> -		intel_de_write(dev_priv, UTIL_PIN_CTL, val);
> -	}
> -}
> -
> -static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 tmp;
> -
> -	intel_panel_set_pwm_level(old_conn_state, val);
> -
> -	tmp = intel_de_read(dev_priv,
> -			    BXT_BLC_PWM_CTL(panel->backlight.controller));
> -	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> -		       tmp & ~BXT_BLC_PWM_ENABLE);
> -}
> -
> -static void ext_pwm_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	panel->backlight.pwm_state.enabled = false;
> -	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> -}
> -
> -void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state)
> -{
> -	struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	if (!panel->backlight.present)
> -		return;
> -
> -	/*
> -	 * Do not disable backlight on the vga_switcheroo path. When switching
> -	 * away from i915, the other client may depend on i915 to handle the
> -	 * backlight. This will leave the backlight on unnecessarily when
> -	 * another client is not activated.
> -	 */
> -	if (dev_priv->drm.switch_power_state == DRM_SWITCH_POWER_CHANGING) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "Skipping backlight disable on vga switch\n");
> -		return;
> -	}
> -
> -	mutex_lock(&dev_priv->backlight_lock);
> -
> -	if (panel->backlight.device)
> -		panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
> -	panel->backlight.enabled = false;
> -	panel->backlight.funcs->disable(old_conn_state, 0);
> -
> -	mutex_unlock(&dev_priv->backlight_lock);
> -}
> -
> -static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				 const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 pch_ctl1, pch_ctl2, schicken;
> -
> -	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
> -		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
> -		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> -	}
> -
> -	if (HAS_PCH_LPT(dev_priv)) {
> -		schicken = intel_de_read(dev_priv, SOUTH_CHICKEN2);
> -		if (panel->backlight.alternate_pwm_increment)
> -			schicken |= LPT_PWM_GRANULARITY;
> -		else
> -			schicken &= ~LPT_PWM_GRANULARITY;
> -		intel_de_write(dev_priv, SOUTH_CHICKEN2, schicken);
> -	} else {
> -		schicken = intel_de_read(dev_priv, SOUTH_CHICKEN1);
> -		if (panel->backlight.alternate_pwm_increment)
> -			schicken |= SPT_PWM_GRANULARITY;
> -		else
> -			schicken &= ~SPT_PWM_GRANULARITY;
> -		intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken);
> -	}
> -
> -	pch_ctl2 = panel->backlight.pwm_level_max << 16;
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
> -
> -	pch_ctl1 = 0;
> -	if (panel->backlight.active_low_pwm)
> -		pch_ctl1 |= BLM_PCH_POLARITY;
> -
> -	/* After LPT, override is the default. */
> -	if (HAS_PCH_LPT(dev_priv))
> -		pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
> -
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> -	intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
> -		       pch_ctl1 | BLM_PCH_PWM_ENABLE);
> -
> -	/* This won't stick until the above enable. */
> -	intel_panel_set_pwm_level(conn_state, level);
> -}
> -
> -static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				 const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> -	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
> -
> -	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> -	if (cpu_ctl2 & BLM_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "cpu backlight already enabled\n");
> -		cpu_ctl2 &= ~BLM_PWM_ENABLE;
> -		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
> -	}
> -
> -	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
> -		pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
> -		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> -	}
> -
> -	if (cpu_transcoder == TRANSCODER_EDP)
> -		cpu_ctl2 = BLM_TRANSCODER_EDP;
> -	else
> -		cpu_ctl2 = BLM_PIPE(cpu_transcoder);
> -	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
> -	intel_de_posting_read(dev_priv, BLC_PWM_CPU_CTL2);
> -	intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
> -
> -	/* This won't stick until the above enable. */
> -	intel_panel_set_pwm_level(conn_state, level);
> -
> -	pch_ctl2 = panel->backlight.pwm_level_max << 16;
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
> -
> -	pch_ctl1 = 0;
> -	if (panel->backlight.active_low_pwm)
> -		pch_ctl1 |= BLM_PCH_POLARITY;
> -
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
> -	intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
> -		       pch_ctl1 | BLM_PCH_PWM_ENABLE);
> -}
> -
> -static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				  const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 ctl, freq;
> -
> -	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
> -	if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
> -		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> -		intel_de_write(dev_priv, BLC_PWM_CTL, 0);
> -	}
> -
> -	freq = panel->backlight.pwm_level_max;
> -	if (panel->backlight.combination_mode)
> -		freq /= 0xff;
> -
> -	ctl = freq << 17;
> -	if (panel->backlight.combination_mode)
> -		ctl |= BLM_LEGACY_MODE;
> -	if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
> -		ctl |= BLM_POLARITY_PNV;
> -
> -	intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
> -	intel_de_posting_read(dev_priv, BLC_PWM_CTL);
> -
> -	/* XXX: combine this into above write? */
> -	intel_panel_set_pwm_level(conn_state, level);
> -
> -	/*
> -	 * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
> -	 * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
> -	 * that has backlight.
> -	 */
> -	if (DISPLAY_VER(dev_priv) == 2)
> -		intel_de_write(dev_priv, BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
> -}
> -
> -static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				  const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
> -	u32 ctl, ctl2, freq;
> -
> -	ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
> -	if (ctl2 & BLM_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> -		ctl2 &= ~BLM_PWM_ENABLE;
> -		intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
> -	}
> -
> -	freq = panel->backlight.pwm_level_max;
> -	if (panel->backlight.combination_mode)
> -		freq /= 0xff;
> -
> -	ctl = freq << 16;
> -	intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
> -
> -	ctl2 = BLM_PIPE(pipe);
> -	if (panel->backlight.combination_mode)
> -		ctl2 |= BLM_COMBINATION_MODE;
> -	if (panel->backlight.active_low_pwm)
> -		ctl2 |= BLM_POLARITY_I965;
> -	intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
> -	intel_de_posting_read(dev_priv, BLC_PWM_CTL2);
> -	intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
> -
> -	intel_panel_set_pwm_level(conn_state, level);
> -}
> -
> -static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				 const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> -	u32 ctl, ctl2;
> -
> -	ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> -	if (ctl2 & BLM_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> -		ctl2 &= ~BLM_PWM_ENABLE;
> -		intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
> -	}
> -
> -	ctl = panel->backlight.pwm_level_max << 16;
> -	intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);
> -
> -	/* XXX: combine this into above write? */
> -	intel_panel_set_pwm_level(conn_state, level);
> -
> -	ctl2 = 0;
> -	if (panel->backlight.active_low_pwm)
> -		ctl2 |= BLM_POLARITY_I965;
> -	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
> -	intel_de_posting_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> -	intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
> -		       ctl2 | BLM_PWM_ENABLE);
> -}
> -
> -static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				 const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> -	u32 pwm_ctl, val;
> -
> -	/* Controller 1 uses the utility pin. */
> -	if (panel->backlight.controller == 1) {
> -		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
> -		if (val & UTIL_PIN_ENABLE) {
> -			drm_dbg_kms(&dev_priv->drm,
> -				    "util pin already enabled\n");
> -			val &= ~UTIL_PIN_ENABLE;
> -			intel_de_write(dev_priv, UTIL_PIN_CTL, val);
> -		}
> -
> -		val = 0;
> -		if (panel->backlight.util_pin_active_low)
> -			val |= UTIL_PIN_POLARITY;
> -		intel_de_write(dev_priv, UTIL_PIN_CTL,
> -			       val | UTIL_PIN_PIPE(pipe) | UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
> -	}
> -
> -	pwm_ctl = intel_de_read(dev_priv,
> -				BXT_BLC_PWM_CTL(panel->backlight.controller));
> -	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> -		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
> -		intel_de_write(dev_priv,
> -			       BXT_BLC_PWM_CTL(panel->backlight.controller),
> -			       pwm_ctl);
> -	}
> -
> -	intel_de_write(dev_priv,
> -		       BXT_BLC_PWM_FREQ(panel->backlight.controller),
> -		       panel->backlight.pwm_level_max);
> -
> -	intel_panel_set_pwm_level(conn_state, level);
> -
> -	pwm_ctl = 0;
> -	if (panel->backlight.active_low_pwm)
> -		pwm_ctl |= BXT_BLC_PWM_POLARITY;
> -
> -	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> -		       pwm_ctl);
> -	intel_de_posting_read(dev_priv,
> -			      BXT_BLC_PWM_CTL(panel->backlight.controller));
> -	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> -		       pwm_ctl | BXT_BLC_PWM_ENABLE);
> -}
> -
> -static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				 const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 pwm_ctl;
> -
> -	pwm_ctl = intel_de_read(dev_priv,
> -				BXT_BLC_PWM_CTL(panel->backlight.controller));
> -	if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
> -		drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
> -		pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
> -		intel_de_write(dev_priv,
> -			       BXT_BLC_PWM_CTL(panel->backlight.controller),
> -			       pwm_ctl);
> -	}
> -
> -	intel_de_write(dev_priv,
> -		       BXT_BLC_PWM_FREQ(panel->backlight.controller),
> -		       panel->backlight.pwm_level_max);
> -
> -	intel_panel_set_pwm_level(conn_state, level);
> -
> -	pwm_ctl = 0;
> -	if (panel->backlight.active_low_pwm)
> -		pwm_ctl |= BXT_BLC_PWM_POLARITY;
> -
> -	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> -		       pwm_ctl);
> -	intel_de_posting_read(dev_priv,
> -			      BXT_BLC_PWM_CTL(panel->backlight.controller));
> -	intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
> -		       pwm_ctl | BXT_BLC_PWM_ENABLE);
> -}
> -
> -static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				     const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
> -	panel->backlight.pwm_state.enabled = true;
> -	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> -}
> -
> -static void __intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
> -					   const struct drm_connector_state *conn_state)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	WARN_ON(panel->backlight.max == 0);
> -
> -	if (panel->backlight.level <= panel->backlight.min) {
> -		panel->backlight.level = panel->backlight.max;
> -		if (panel->backlight.device)
> -			panel->backlight.device->props.brightness =
> -				scale_hw_to_user(connector,
> -						 panel->backlight.level,
> -						 panel->backlight.device->props.max_brightness);
> -	}
> -
> -	panel->backlight.funcs->enable(crtc_state, conn_state, panel->backlight.level);
> -	panel->backlight.enabled = true;
> -	if (panel->backlight.device)
> -		panel->backlight.device->props.power = FB_BLANK_UNBLANK;
> -}
> -
> -void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				  const struct drm_connector_state *conn_state)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
> -
> -	if (!panel->backlight.present)
> -		return;
> -
> -	drm_dbg_kms(&dev_priv->drm, "pipe %c\n", pipe_name(pipe));
> -
> -	mutex_lock(&dev_priv->backlight_lock);
> -
> -	__intel_panel_enable_backlight(crtc_state, conn_state);
> -
> -	mutex_unlock(&dev_priv->backlight_lock);
> -}
> -
> -#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
> -static u32 intel_panel_get_backlight(struct intel_connector *connector)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 val = 0;
> -
> -	mutex_lock(&dev_priv->backlight_lock);
> -
> -	if (panel->backlight.enabled)
> -		val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
> -
> -	mutex_unlock(&dev_priv->backlight_lock);
> -
> -	drm_dbg_kms(&dev_priv->drm, "get backlight PWM = %d\n", val);
> -	return val;
> -}
> -
> -/* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
> -static u32 scale_user_to_hw(struct intel_connector *connector,
> -			    u32 user_level, u32 user_max)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -
> -	return scale(user_level, 0, user_max,
> -		     panel->backlight.min, panel->backlight.max);
> -}
> -
> -/* set backlight brightness to level in range [0..max], scaling wrt hw min */
> -static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
> -				      u32 user_level, u32 user_max)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 hw_level;
> -
> -	if (!panel->backlight.present)
> -		return;
> -
> -	mutex_lock(&dev_priv->backlight_lock);
> -
> -	drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
> -
> -	hw_level = scale_user_to_hw(connector, user_level, user_max);
> -	panel->backlight.level = hw_level;
> -
> -	if (panel->backlight.enabled)
> -		intel_panel_actually_set_backlight(conn_state, hw_level);
> -
> -	mutex_unlock(&dev_priv->backlight_lock);
> -}
> -
> -static int intel_backlight_device_update_status(struct backlight_device *bd)
> -{
> -	struct intel_connector *connector = bl_get_data(bd);
> -	struct intel_panel *panel = &connector->panel;
> -	struct drm_device *dev = connector->base.dev;
> -
> -	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> -	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
> -		      bd->props.brightness, bd->props.max_brightness);
> -	intel_panel_set_backlight(connector->base.state, bd->props.brightness,
> -				  bd->props.max_brightness);
> -
> -	/*
> -	 * Allow flipping bl_power as a sub-state of enabled. Sadly the
> -	 * backlight class device does not make it easy to to differentiate
> -	 * between callbacks for brightness and bl_power, so our backlight_power
> -	 * callback needs to take this into account.
> -	 */
> -	if (panel->backlight.enabled) {
> -		if (panel->backlight.power) {
> -			bool enable = bd->props.power == FB_BLANK_UNBLANK &&
> -				bd->props.brightness != 0;
> -			panel->backlight.power(connector, enable);
> -		}
> -	} else {
> -		bd->props.power = FB_BLANK_POWERDOWN;
> -	}
> -
> -	drm_modeset_unlock(&dev->mode_config.connection_mutex);
> -	return 0;
> -}
> -
> -static int intel_backlight_device_get_brightness(struct backlight_device *bd)
> -{
> -	struct intel_connector *connector = bl_get_data(bd);
> -	struct drm_device *dev = connector->base.dev;
> -	struct drm_i915_private *dev_priv = to_i915(dev);
> -	intel_wakeref_t wakeref;
> -	int ret = 0;
> -
> -	with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref) {
> -		u32 hw_level;
> -
> -		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> -
> -		hw_level = intel_panel_get_backlight(connector);
> -		ret = scale_hw_to_user(connector,
> -				       hw_level, bd->props.max_brightness);
> -
> -		drm_modeset_unlock(&dev->mode_config.connection_mutex);
> -	}
> -
> -	return ret;
> -}
> -
> -static const struct backlight_ops intel_backlight_device_ops = {
> -	.update_status = intel_backlight_device_update_status,
> -	.get_brightness = intel_backlight_device_get_brightness,
> -};
> -
> -int intel_backlight_device_register(struct intel_connector *connector)
> -{
> -	struct drm_i915_private *i915 = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	struct backlight_properties props;
> -	struct backlight_device *bd;
> -	const char *name;
> -	int ret = 0;
> -
> -	if (WARN_ON(panel->backlight.device))
> -		return -ENODEV;
> -
> -	if (!panel->backlight.present)
> -		return 0;
> -
> -	WARN_ON(panel->backlight.max == 0);
> -
> -	memset(&props, 0, sizeof(props));
> -	props.type = BACKLIGHT_RAW;
> -
> -	/*
> -	 * Note: Everything should work even if the backlight device max
> -	 * presented to the userspace is arbitrarily chosen.
> -	 */
> -	props.max_brightness = panel->backlight.max;
> -	props.brightness = scale_hw_to_user(connector,
> -					    panel->backlight.level,
> -					    props.max_brightness);
> -
> -	if (panel->backlight.enabled)
> -		props.power = FB_BLANK_UNBLANK;
> -	else
> -		props.power = FB_BLANK_POWERDOWN;
> -
> -	name = kstrdup("intel_backlight", GFP_KERNEL);
> -	if (!name)
> -		return -ENOMEM;
> -
> -	bd = backlight_device_register(name, connector->base.kdev, connector,
> -				       &intel_backlight_device_ops, &props);
> -
> -	/*
> -	 * Using the same name independent of the drm device or connector
> -	 * prevents registration of multiple backlight devices in the
> -	 * driver. However, we need to use the default name for backward
> -	 * compatibility. Use unique names for subsequent backlight devices as a
> -	 * fallback when the default name already exists.
> -	 */
> -	if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) {
> -		kfree(name);
> -		name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
> -				 i915->drm.primary->index, connector->base.name);
> -		if (!name)
> -			return -ENOMEM;
> -
> -		bd = backlight_device_register(name, connector->base.kdev, connector,
> -					       &intel_backlight_device_ops, &props);
> -	}
> -
> -	if (IS_ERR(bd)) {
> -		drm_err(&i915->drm,
> -			"[CONNECTOR:%d:%s] backlight device %s register failed: %ld\n",
> -			connector->base.base.id, connector->base.name, name, PTR_ERR(bd));
> -		ret = PTR_ERR(bd);
> -		goto out;
> -	}
> -
> -	panel->backlight.device = bd;
> -
> -	drm_dbg_kms(&i915->drm,
> -		    "[CONNECTOR:%d:%s] backlight device %s registered\n",
> -		    connector->base.base.id, connector->base.name, name);
> -
> -out:
> -	kfree(name);
> -
> -	return ret;
> -}
> -
> -void intel_backlight_device_unregister(struct intel_connector *connector)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -
> -	if (panel->backlight.device) {
> -		backlight_device_unregister(panel->backlight.device);
> -		panel->backlight.device = NULL;
> -	}
> -}
> -#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
> -
> -/*
> - * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
> - *      PWM increment = 1
> - */
> -static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
> -				 pwm_freq_hz);
> -}
> -
> -/*
> - * BXT: PWM clock frequency = 19.2 MHz.
> - */
> -static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
> -}
> -
> -/*
> - * SPT: This value represents the period of the PWM stream in clock periods
> - * multiplied by 16 (default increment) or 128 (alternate increment selected in
> - * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
> - */
> -static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -	u32 mul;
> -
> -	if (panel->backlight.alternate_pwm_increment)
> -		mul = 128;
> -	else
> -		mul = 16;
> -
> -	return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
> -}
> -
> -/*
> - * LPT: This value represents the period of the PWM stream in clock periods
> - * multiplied by 128 (default increment) or 16 (alternate increment, selected in
> - * LPT SOUTH_CHICKEN2 register bit 5).
> - */
> -static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 mul, clock;
> -
> -	if (panel->backlight.alternate_pwm_increment)
> -		mul = 16;
> -	else
> -		mul = 128;
> -
> -	if (HAS_PCH_LPT_H(dev_priv))
> -		clock = MHz(135); /* LPT:H */
> -	else
> -		clock = MHz(24); /* LPT:LP */
> -
> -	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
> -}
> -
> -/*
> - * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
> - * display raw clocks multiplied by 128.
> - */
> -static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
> -				 pwm_freq_hz * 128);
> -}
> -
> -/*
> - * Gen2: This field determines the number of time base events (display core
> - * clock frequency/32) in total for a complete cycle of modulated backlight
> - * control.
> - *
> - * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
> - * divided by 32.
> - */
> -static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	int clock;
> -
> -	if (IS_PINEVIEW(dev_priv))
> -		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
> -	else
> -		clock = KHz(dev_priv->cdclk.hw.cdclk);
> -
> -	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
> -}
> -
> -/*
> - * Gen4: This value represents the period of the PWM stream in display core
> - * clocks ([DevCTG] HRAW clocks) multiplied by 128.
> - *
> - */
> -static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	int clock;
> -
> -	if (IS_G4X(dev_priv))
> -		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
> -	else
> -		clock = KHz(dev_priv->cdclk.hw.cdclk);
> -
> -	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
> -}
> -
> -/*
> - * VLV: This value represents the period of the PWM stream in display core
> - * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
> - * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
> - */
> -static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	int mul, clock;
> -
> -	if ((intel_de_read(dev_priv, CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
> -		if (IS_CHERRYVIEW(dev_priv))
> -			clock = KHz(19200);
> -		else
> -			clock = MHz(25);
> -		mul = 16;
> -	} else {
> -		clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
> -		mul = 128;
> -	}
> -
> -	return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
> -}
> -
> -static u16 get_vbt_pwm_freq(struct drm_i915_private *dev_priv)
> -{
> -	u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz;
> -
> -	if (pwm_freq_hz) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "VBT defined backlight frequency %u Hz\n",
> -			    pwm_freq_hz);
> -	} else {
> -		pwm_freq_hz = 200;
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "default backlight frequency %u Hz\n",
> -			    pwm_freq_hz);
> -	}
> -
> -	return pwm_freq_hz;
> -}
> -
> -static u32 get_backlight_max_vbt(struct intel_connector *connector)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv);
> -	u32 pwm;
> -
> -	if (!panel->backlight.pwm_funcs->hz_to_pwm) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "backlight frequency conversion not supported\n");
> -		return 0;
> -	}
> -
> -	pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz);
> -	if (!pwm) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "backlight frequency conversion failed\n");
> -		return 0;
> -	}
> -
> -	return pwm;
> -}
> -
> -/*
> - * Note: The setup hooks can't assume pipe is set!
> - */
> -static u32 get_backlight_min_vbt(struct intel_connector *connector)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	int min;
> -
> -	drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
> -
> -	/*
> -	 * XXX: If the vbt value is 255, it makes min equal to max, which leads
> -	 * to problems. There are such machines out there. Either our
> -	 * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
> -	 * against this by letting the minimum be at most (arbitrarily chosen)
> -	 * 25% of the max.
> -	 */
> -	min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
> -	if (min != dev_priv->vbt.backlight.min_brightness) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "clamping VBT min backlight %d/255 to %d/255\n",
> -			    dev_priv->vbt.backlight.min_brightness, min);
> -	}
> -
> -	/* vbt value is a coefficient in range [0..255] */
> -	return scale(min, 0, 255, 0, panel->backlight.pwm_level_max);
> -}
> -
> -static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
> -	bool alt, cpu_mode;
> -
> -	if (HAS_PCH_LPT(dev_priv))
> -		alt = intel_de_read(dev_priv, SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY;
> -	else
> -		alt = intel_de_read(dev_priv, SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY;
> -	panel->backlight.alternate_pwm_increment = alt;
> -
> -	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
> -
> -	pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
> -	panel->backlight.pwm_level_max = pch_ctl2 >> 16;
> -
> -	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;
> -
> -	cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) &&
> -		   !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
> -		   (cpu_ctl2 & BLM_PWM_ENABLE);
> -
> -	if (cpu_mode) {
> -		val = pch_get_backlight(connector, unused);
> -
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "CPU backlight register was enabled, switching to PCH override\n");
> -
> -		/* Write converted CPU PWM value to PCH override register */
> -		lpt_set_backlight(connector->base.state, val);
> -		intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
> -			       pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE);
> -
> -		intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
> -			       cpu_ctl2 & ~BLM_PWM_ENABLE);
> -	}
> -
> -	return 0;
> -}
> -
> -static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 cpu_ctl2, pch_ctl1, pch_ctl2;
> -
> -	pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
> -	panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
> -
> -	pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
> -	panel->backlight.pwm_level_max = pch_ctl2 >> 16;
> -
> -	if (!panel->backlight.pwm_level_max)
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
> -	panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
> -		(pch_ctl1 & BLM_PCH_PWM_ENABLE);
> -
> -	return 0;
> -}
> -
> -static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 ctl, val;
> -
> -	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
> -
> -	if (DISPLAY_VER(dev_priv) == 2 || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
> -		panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
> -
> -	if (IS_PINEVIEW(dev_priv))
> -		panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
> -
> -	panel->backlight.pwm_level_max = ctl >> 17;
> -
> -	if (!panel->backlight.pwm_level_max) {
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -		panel->backlight.pwm_level_max >>= 1;
> -	}
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	if (panel->backlight.combination_mode)
> -		panel->backlight.pwm_level_max *= 0xff;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	val = i9xx_get_backlight(connector, unused);
> -	val = intel_panel_invert_pwm_level(connector, val);
> -	val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
> -
> -	panel->backlight.pwm_enabled = val != 0;
> -
> -	return 0;
> -}
> -
> -static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 ctl, ctl2;
> -
> -	ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
> -	panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
> -	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
> -
> -	ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
> -	panel->backlight.pwm_level_max = ctl >> 16;
> -
> -	if (!panel->backlight.pwm_level_max)
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	if (panel->backlight.combination_mode)
> -		panel->backlight.pwm_level_max *= 0xff;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
> -
> -	return 0;
> -}
> -
> -static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 ctl, ctl2;
> -
> -	if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
> -		return -ENODEV;
> -
> -	ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
> -	panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
> -
> -	ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe));
> -	panel->backlight.pwm_level_max = ctl >> 16;
> -
> -	if (!panel->backlight.pwm_level_max)
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
> -
> -	return 0;
> -}
> -
> -static int
> -bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 pwm_ctl, val;
> -
> -	panel->backlight.controller = dev_priv->vbt.backlight.controller;
> -
> -	pwm_ctl = intel_de_read(dev_priv,
> -				BXT_BLC_PWM_CTL(panel->backlight.controller));
> -
> -	/* Controller 1 uses the utility pin. */
> -	if (panel->backlight.controller == 1) {
> -		val = intel_de_read(dev_priv, UTIL_PIN_CTL);
> -		panel->backlight.util_pin_active_low =
> -					val & UTIL_PIN_POLARITY;
> -	}
> -
> -	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
> -	panel->backlight.pwm_level_max =
> -		intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
> -
> -	if (!panel->backlight.pwm_level_max)
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
> -
> -	return 0;
> -}
> -
> -static int
> -cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -	u32 pwm_ctl;
> -
> -	/*
> -	 * CNP has the BXT implementation of backlight, but with only one
> -	 * controller. TODO: ICP has multiple controllers but we only use
> -	 * controller 0 for now.
> -	 */
> -	panel->backlight.controller = 0;
> -
> -	pwm_ctl = intel_de_read(dev_priv,
> -				BXT_BLC_PWM_CTL(panel->backlight.controller));
> -
> -	panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
> -	panel->backlight.pwm_level_max =
> -		intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
> -
> -	if (!panel->backlight.pwm_level_max)
> -		panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
> -
> -	if (!panel->backlight.pwm_level_max)
> -		return -ENODEV;
> -
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
> -
> -	return 0;
> -}
> -
> -static int ext_pwm_setup_backlight(struct intel_connector *connector,
> -				   enum pipe pipe)
> -{
> -	struct drm_device *dev = connector->base.dev;
> -	struct drm_i915_private *dev_priv = to_i915(dev);
> -	struct intel_panel *panel = &connector->panel;
> -	const char *desc;
> -	u32 level;
> -
> -	/* Get the right PWM chip for DSI backlight according to VBT */
> -	if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
> -		panel->backlight.pwm = pwm_get(dev->dev, "pwm_pmic_backlight");
> -		desc = "PMIC";
> -	} else {
> -		panel->backlight.pwm = pwm_get(dev->dev, "pwm_soc_backlight");
> -		desc = "SoC";
> -	}
> -
> -	if (IS_ERR(panel->backlight.pwm)) {
> -		drm_err(&dev_priv->drm, "Failed to get the %s PWM chip\n",
> -			desc);
> -		panel->backlight.pwm = NULL;
> -		return -ENODEV;
> -	}
> -
> -	panel->backlight.pwm_level_max = 100; /* 100% */
> -	panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
> -
> -	if (pwm_is_enabled(panel->backlight.pwm)) {
> -		/* PWM is already enabled, use existing settings */
> -		pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state);
> -
> -		level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state,
> -						    100);
> -		level = intel_panel_invert_pwm_level(connector, level);
> -		panel->backlight.pwm_enabled = true;
> -
> -		drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n",
> -			    NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period,
> -			    get_vbt_pwm_freq(dev_priv), level);
> -	} else {
> -		/* Set period from VBT frequency, leave other settings at 0. */
> -		panel->backlight.pwm_state.period =
> -			NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv);
> -	}
> -
> -	drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",
> -		 desc);
> -	return 0;
> -}
> -
> -static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	panel->backlight.pwm_funcs->set(conn_state,
> -				       intel_panel_invert_pwm_level(connector, level));
> -}
> -
> -static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -
> -	return intel_panel_invert_pwm_level(connector,
> -					    panel->backlight.pwm_funcs->get(connector, pipe));
> -}
> -
> -static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				       const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	panel->backlight.pwm_funcs->enable(crtc_state, conn_state,
> -					   intel_panel_invert_pwm_level(connector, level));
> -}
> -
> -static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	panel->backlight.pwm_funcs->disable(conn_state,
> -					    intel_panel_invert_pwm_level(connector, level));
> -}
> -
> -static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe)
> -{
> -	struct intel_panel *panel = &connector->panel;
> -	int ret = panel->backlight.pwm_funcs->setup(connector, pipe);
> -
> -	if (ret < 0)
> -		return ret;
> -
> -	panel->backlight.min = panel->backlight.pwm_level_min;
> -	panel->backlight.max = panel->backlight.pwm_level_max;
> -	panel->backlight.level = intel_pwm_get_backlight(connector, pipe);
> -	panel->backlight.enabled = panel->backlight.pwm_enabled;
> -
> -	return 0;
> -}
> -
> -void intel_panel_update_backlight(struct intel_atomic_state *state,
> -				  struct intel_encoder *encoder,
> -				  const struct intel_crtc_state *crtc_state,
> -				  const struct drm_connector_state *conn_state)
> -{
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -	struct intel_panel *panel = &connector->panel;
> -
> -	if (!panel->backlight.present)
> -		return;
> -
> -	mutex_lock(&dev_priv->backlight_lock);
> -	if (!panel->backlight.enabled)
> -		__intel_panel_enable_backlight(crtc_state, conn_state);
> -
> -	mutex_unlock(&dev_priv->backlight_lock);
> -}
> -
> -int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
> -{
> -	struct drm_i915_private *dev_priv = to_i915(connector->dev);
> -	struct intel_connector *intel_connector = to_intel_connector(connector);
> -	struct intel_panel *panel = &intel_connector->panel;
> -	int ret;
> -
> -	if (!dev_priv->vbt.backlight.present) {
> -		if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
> -			drm_dbg_kms(&dev_priv->drm,
> -				    "no backlight present per VBT, but present per quirk\n");
> -		} else {
> -			drm_dbg_kms(&dev_priv->drm,
> -				    "no backlight present per VBT\n");
> -			return 0;
> -		}
> -	}
> -
> -	/* ensure intel_panel has been initialized first */
> -	if (drm_WARN_ON(&dev_priv->drm, !panel->backlight.funcs))
> -		return -ENODEV;
> -
> -	/* set level and max in panel struct */
> -	mutex_lock(&dev_priv->backlight_lock);
> -	ret = panel->backlight.funcs->setup(intel_connector, pipe);
> -	mutex_unlock(&dev_priv->backlight_lock);
> -
> -	if (ret) {
> -		drm_dbg_kms(&dev_priv->drm,
> -			    "failed to setup backlight for connector %s\n",
> -			    connector->name);
> -		return ret;
> -	}
> -
> -	panel->backlight.present = true;
> -
> -	drm_dbg_kms(&dev_priv->drm,
> -		    "Connector %s backlight initialized, %s, brightness %u/%u\n",
> -		    connector->name,
> -		    enableddisabled(panel->backlight.enabled),
> -		    panel->backlight.level, panel->backlight.max);
> -
> -	return 0;
> -}
> -
> -static void intel_panel_destroy_backlight(struct intel_panel *panel)
> -{
> -	/* dispose of the pwm */
> -	if (panel->backlight.pwm)
> -		pwm_put(panel->backlight.pwm);
> -
> -	panel->backlight.present = false;
> -}
> -
> -static const struct intel_panel_bl_funcs bxt_pwm_funcs = {
> -	.setup = bxt_setup_backlight,
> -	.enable = bxt_enable_backlight,
> -	.disable = bxt_disable_backlight,
> -	.set = bxt_set_backlight,
> -	.get = bxt_get_backlight,
> -	.hz_to_pwm = bxt_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs cnp_pwm_funcs = {
> -	.setup = cnp_setup_backlight,
> -	.enable = cnp_enable_backlight,
> -	.disable = cnp_disable_backlight,
> -	.set = bxt_set_backlight,
> -	.get = bxt_get_backlight,
> -	.hz_to_pwm = cnp_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs lpt_pwm_funcs = {
> -	.setup = lpt_setup_backlight,
> -	.enable = lpt_enable_backlight,
> -	.disable = lpt_disable_backlight,
> -	.set = lpt_set_backlight,
> -	.get = lpt_get_backlight,
> -	.hz_to_pwm = lpt_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs spt_pwm_funcs = {
> -	.setup = lpt_setup_backlight,
> -	.enable = lpt_enable_backlight,
> -	.disable = lpt_disable_backlight,
> -	.set = lpt_set_backlight,
> -	.get = lpt_get_backlight,
> -	.hz_to_pwm = spt_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs pch_pwm_funcs = {
> -	.setup = pch_setup_backlight,
> -	.enable = pch_enable_backlight,
> -	.disable = pch_disable_backlight,
> -	.set = pch_set_backlight,
> -	.get = pch_get_backlight,
> -	.hz_to_pwm = pch_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs ext_pwm_funcs = {
> -	.setup = ext_pwm_setup_backlight,
> -	.enable = ext_pwm_enable_backlight,
> -	.disable = ext_pwm_disable_backlight,
> -	.set = ext_pwm_set_backlight,
> -	.get = ext_pwm_get_backlight,
> -};
> -
> -static const struct intel_panel_bl_funcs vlv_pwm_funcs = {
> -	.setup = vlv_setup_backlight,
> -	.enable = vlv_enable_backlight,
> -	.disable = vlv_disable_backlight,
> -	.set = vlv_set_backlight,
> -	.get = vlv_get_backlight,
> -	.hz_to_pwm = vlv_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs i965_pwm_funcs = {
> -	.setup = i965_setup_backlight,
> -	.enable = i965_enable_backlight,
> -	.disable = i965_disable_backlight,
> -	.set = i9xx_set_backlight,
> -	.get = i9xx_get_backlight,
> -	.hz_to_pwm = i965_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs i9xx_pwm_funcs = {
> -	.setup = i9xx_setup_backlight,
> -	.enable = i9xx_enable_backlight,
> -	.disable = i9xx_disable_backlight,
> -	.set = i9xx_set_backlight,
> -	.get = i9xx_get_backlight,
> -	.hz_to_pwm = i9xx_hz_to_pwm,
> -};
> -
> -static const struct intel_panel_bl_funcs pwm_bl_funcs = {
> -	.setup = intel_pwm_setup_backlight,
> -	.enable = intel_pwm_enable_backlight,
> -	.disable = intel_pwm_disable_backlight,
> -	.set = intel_pwm_set_backlight,
> -	.get = intel_pwm_get_backlight,
> -};
> -
> -/* Set up chip specific backlight functions */
> -static void
> -intel_panel_init_backlight_funcs(struct intel_panel *panel)
> -{
> -	struct intel_connector *connector =
> -		container_of(panel, struct intel_connector, panel);
> -	struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
> -
> -	if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
> -	    intel_dsi_dcs_init_backlight_funcs(connector) == 0)
> -		return;
> -
> -	if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
> -		panel->backlight.pwm_funcs = &bxt_pwm_funcs;
> -	} else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) {
> -		panel->backlight.pwm_funcs = &cnp_pwm_funcs;
> -	} else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) {
> -		if (HAS_PCH_LPT(dev_priv))
> -			panel->backlight.pwm_funcs = &lpt_pwm_funcs;
> -		else
> -			panel->backlight.pwm_funcs = &spt_pwm_funcs;
> -	} else if (HAS_PCH_SPLIT(dev_priv)) {
> -		panel->backlight.pwm_funcs = &pch_pwm_funcs;
> -	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
> -		if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
> -			panel->backlight.pwm_funcs = &ext_pwm_funcs;
> -		} else {
> -			panel->backlight.pwm_funcs = &vlv_pwm_funcs;
> -		}
> -	} else if (DISPLAY_VER(dev_priv) == 4) {
> -		panel->backlight.pwm_funcs = &i965_pwm_funcs;
> -	} else {
> -		panel->backlight.pwm_funcs = &i9xx_pwm_funcs;
> -	}
> -
> -	if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP &&
> -	    intel_dp_aux_init_backlight_funcs(connector) == 0)
> -		return;
> -
> -	/* We're using a standard PWM backlight interface */
> -	panel->backlight.funcs = &pwm_bl_funcs;
> -}
> -
>  enum drm_connector_status
>  intel_panel_detect(struct drm_connector *connector, bool force)
>  {
> diff --git a/drivers/gpu/drm/i915/display/intel_panel.h b/drivers/gpu/drm/i915/display/intel_panel.h
> index 1d340f77bffc7..67dbb15026bf1 100644
> --- a/drivers/gpu/drm/i915/display/intel_panel.h
> +++ b/drivers/gpu/drm/i915/display/intel_panel.h
> @@ -8,15 +8,13 @@
>  
>  #include <linux/types.h>
>  
> -#include "intel_display.h"
> -
> +enum drm_connector_status;
>  struct drm_connector;
>  struct drm_connector_state;
>  struct drm_display_mode;
> +struct drm_i915_private;
>  struct intel_connector;
> -struct intel_crtc;
>  struct intel_crtc_state;
> -struct intel_encoder;
>  struct intel_panel;
>  
>  int intel_panel_init(struct intel_panel *panel,
> @@ -31,17 +29,6 @@ int intel_pch_panel_fitting(struct intel_crtc_state *crtc_state,
>  			    const struct drm_connector_state *conn_state);
>  int intel_gmch_panel_fitting(struct intel_crtc_state *crtc_state,
>  			     const struct drm_connector_state *conn_state);
> -void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
> -				    u32 level, u32 max);
> -int intel_panel_setup_backlight(struct drm_connector *connector,
> -				enum pipe pipe);
> -void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
> -				  const struct drm_connector_state *conn_state);
> -void intel_panel_update_backlight(struct intel_atomic_state *state,
> -				  struct intel_encoder *encoder,
> -				  const struct intel_crtc_state *crtc_state,
> -				  const struct drm_connector_state *conn_state);
> -void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state);
>  struct drm_display_mode *
>  intel_panel_edid_downclock_mode(struct intel_connector *connector,
>  				const struct drm_display_mode *fixed_mode);
> @@ -49,22 +36,5 @@ struct drm_display_mode *
>  intel_panel_edid_fixed_mode(struct intel_connector *connector);
>  struct drm_display_mode *
>  intel_panel_vbt_fixed_mode(struct intel_connector *connector);
> -void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 level);
> -u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 level);
> -u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 level);
> -u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val);
> -
> -#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
> -int intel_backlight_device_register(struct intel_connector *connector);
> -void intel_backlight_device_unregister(struct intel_connector *connector);
> -#else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
> -static inline int intel_backlight_device_register(struct intel_connector *connector)
> -{
> -	return 0;
> -}
> -static inline void intel_backlight_device_unregister(struct intel_connector *connector)
> -{
> -}
> -#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
>  
>  #endif /* __INTEL_PANEL_H__ */
> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
> index 0ee4ff341e25d..b27738df447d0 100644
> --- a/drivers/gpu/drm/i915/display/vlv_dsi.c
> +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
> @@ -32,6 +32,7 @@
>  
>  #include "i915_drv.h"
>  #include "intel_atomic.h"
> +#include "intel_backlight.h"
>  #include "intel_connector.h"
>  #include "intel_crtc.h"
>  #include "intel_de.h"

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat