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Date: Thu, 18 Apr 2024 14:46:18 +0300
From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
To: lvzhaoxiong <lvzhaoxiong@huaqin.corp-partner.google.com>
Cc: mripard@kernel.org, airlied@gmail.com, daniel@ffwll.ch, 
	robh@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, 
	dianders@google.com, hsinyi@google.com, dri-devel@lists.freedesktop.org, 
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1 2/2] drm/panel: kd101ne3: add new panel driver
Message-ID: <zanx5y3obqmewnbooovf52hx6vh7tpi4zsbse2dyzcqzddmzhw@kewxoa6n3mja>
References: <20240418081548.12160-1-lvzhaoxiong@huaqin.corp-partner.google.com>
 <20240418081548.12160-3-lvzhaoxiong@huaqin.corp-partner.google.com>
Precedence: bulk
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In-Reply-To: <20240418081548.12160-3-lvzhaoxiong@huaqin.corp-partner.google.com>

On Thu, Apr 18, 2024 at 04:15:48PM +0800, lvzhaoxiong wrote:
> The kingdisplay panel is based on JD9365DA controller.
> Add a driver for it.
> 
> Signed-off-by: lvzhaoxiong <lvzhaoxiong@huaqin.corp-partner.google.com>
> ---
>  drivers/gpu/drm/panel/Kconfig                 |   9 +
>  drivers/gpu/drm/panel/Makefile                |   1 +
>  .../drm/panel/panel-kingdisplay-kd101ne3.c    | 607 ++++++++++++++++++
>  3 files changed, 617 insertions(+)
>  create mode 100644 drivers/gpu/drm/panel/panel-kingdisplay-kd101ne3.c
> 
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index 154f5bf82980..2c73086cf102 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -297,6 +297,15 @@ config DRM_PANEL_KINGDISPLAY_KD097D04
>  	  24 bit RGB per pixel. It provides a MIPI DSI interface to
>  	  the host and has a built-in LED backlight.
>  
> +config DRM_PANEL_KINGDISPLAY_KD101NE3
> +	tristate "Kingdisplay kd101ne3 panel"
> +	depends on OF
> +	depends on DRM_MIPI_DSI
> +	depends on BACKLIGHT_CLASS_DEVICE
> +	help
> +	  Say Y if you want to enable support for panels based on the
> +	  Kingdisplay kd101ne3 controller.
> +
>  config DRM_PANEL_LEADTEK_LTK050H3146W
>  	tristate "Leadtek LTK050H3146W panel"
>  	depends on OF
> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
> index 24a02655d726..cbd414b98bb0 100644
> --- a/drivers/gpu/drm/panel/Makefile
> +++ b/drivers/gpu/drm/panel/Makefile
> @@ -30,6 +30,7 @@ obj-$(CONFIG_DRM_PANEL_JDI_LPM102A188A) += panel-jdi-lpm102a188a.o
>  obj-$(CONFIG_DRM_PANEL_JDI_R63452) += panel-jdi-fhd-r63452.o
>  obj-$(CONFIG_DRM_PANEL_KHADAS_TS050) += panel-khadas-ts050.o
>  obj-$(CONFIG_DRM_PANEL_KINGDISPLAY_KD097D04) += panel-kingdisplay-kd097d04.o
> +obj-$(CONFIG_DRM_PANEL_KINGDISPLAY_KD101NE3) += panel-kingdisplay-kd101ne3.o
>  obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o
>  obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o
>  obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o
> diff --git a/drivers/gpu/drm/panel/panel-kingdisplay-kd101ne3.c b/drivers/gpu/drm/panel/panel-kingdisplay-kd101ne3.c
> new file mode 100644
> index 000000000000..dbf0992f8b81
> --- /dev/null
> +++ b/drivers/gpu/drm/panel/panel-kingdisplay-kd101ne3.c
> @@ -0,0 +1,607 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Panels based on the JD9365DA display controller.
> + * Author: Zhaoxiong Lv <lvzhaoxiong@huaqin.corp-partner.google.com>
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <drm/drm_connector.h>
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_panel.h>
> +
> +#include <video/mipi_display.h>
> +
> +struct panel_desc {
> +	const struct drm_display_mode *modes;
> +	unsigned int bpc;
> +
> +	/**
> +	 * @width_mm: width of the panel's active display area
> +	 * @height_mm: height of the panel's active display area
> +	 */
> +	struct {
> +		unsigned int width_mm;
> +		unsigned int height_mm;

Please move to the declared mode;

> +	} size;
> +
> +	unsigned long mode_flags;
> +	enum mipi_dsi_pixel_format format;
> +	const struct panel_init_cmd *init_cmds;
> +	unsigned int lanes;
> +	bool discharge_on_disable;
> +	bool lp11_before_reset;
> +};
> +
> +struct kingdisplay_panel {
> +	struct drm_panel base;
> +	struct mipi_dsi_device *dsi;
> +
> +	const struct panel_desc *desc;
> +
> +	enum drm_panel_orientation orientation;
> +	struct regulator *pp3300;
> +	struct gpio_desc *enable_gpio;
> +};
> +
> +enum dsi_cmd_type {
> +	INIT_DCS_CMD,
> +	DELAY_CMD,
> +};
> +
> +struct panel_init_cmd {
> +	enum dsi_cmd_type type;
> +	size_t len;
> +	const char *data;
> +};
> +
> +#define _INIT_DCS_CMD(...) { \
> +	.type = INIT_DCS_CMD, \
> +	.len = sizeof((char[]){__VA_ARGS__}), \
> +	.data = (char[]){__VA_ARGS__} }
> +
> +#define _INIT_DELAY_CMD(...) { \
> +	.type = DELAY_CMD,\
> +	.len = sizeof((char[]){__VA_ARGS__}), \
> +	.data = (char[]){__VA_ARGS__} }

This is the third panel driver using the same appoach. Can you use
mipi_dsi_generic_write_seq() instead of the huge table? Or if you prefer
the table, we should extract this framework to a common helper.
(my preference is shifted towards mipi_dsi_generic_write_seq()).

> +
> +static const struct panel_init_cmd kingdisplay_kd101ne3_init_cmd[] = {
> +	_INIT_DELAY_CMD(50),
> +	_INIT_DCS_CMD(0xE0, 0x00),
> +	_INIT_DCS_CMD(0xE1, 0x93),
> +	_INIT_DCS_CMD(0xE2, 0x65),
> +	_INIT_DCS_CMD(0xE3, 0xF8),
> +	_INIT_DCS_CMD(0x80, 0x03),
> +	_INIT_DCS_CMD(0xE0, 0x01),
> +	_INIT_DCS_CMD(0x0C, 0x74),
> +	_INIT_DCS_CMD(0x17, 0x00),
> +	_INIT_DCS_CMD(0x18, 0xC7),
> +	_INIT_DCS_CMD(0x19, 0x01),
> +	_INIT_DCS_CMD(0x1A, 0x00),
> +	_INIT_DCS_CMD(0x1B, 0xC7),
> +	_INIT_DCS_CMD(0x1C, 0x01),
> +	_INIT_DCS_CMD(0x24, 0xFE),
> +	_INIT_DCS_CMD(0x37, 0x19),
> +	_INIT_DCS_CMD(0x35, 0x28),
> +	_INIT_DCS_CMD(0x38, 0x05),
> +	_INIT_DCS_CMD(0x39, 0x08),
> +	_INIT_DCS_CMD(0x3A, 0x12),
> +	_INIT_DCS_CMD(0x3C, 0x7E),
> +	_INIT_DCS_CMD(0x3D, 0xFF),
> +	_INIT_DCS_CMD(0x3E, 0xFF),
> +	_INIT_DCS_CMD(0x3F, 0x7F),
> +	_INIT_DCS_CMD(0x40, 0x06),
> +	_INIT_DCS_CMD(0x41, 0xA0),
> +	_INIT_DCS_CMD(0x43, 0x1E),
> +	_INIT_DCS_CMD(0x44, 0x0B),
> +	_INIT_DCS_CMD(0x55, 0x02),
> +	_INIT_DCS_CMD(0x57, 0x6A),
> +	_INIT_DCS_CMD(0x59, 0x0A),
> +	_INIT_DCS_CMD(0x5A, 0x2E),
> +	_INIT_DCS_CMD(0x5B, 0x1A),
> +	_INIT_DCS_CMD(0x5C, 0x15),
> +	_INIT_DCS_CMD(0x5D, 0x7F),
> +	_INIT_DCS_CMD(0x5E, 0x61),
> +	_INIT_DCS_CMD(0x5F, 0x50),
> +	_INIT_DCS_CMD(0x60, 0x43),
> +	_INIT_DCS_CMD(0x61, 0x3F),
> +	_INIT_DCS_CMD(0x62, 0x32),
> +	_INIT_DCS_CMD(0x63, 0x35),
> +	_INIT_DCS_CMD(0x64, 0x1F),
> +	_INIT_DCS_CMD(0x65, 0x38),
> +	_INIT_DCS_CMD(0x66, 0x36),
> +	_INIT_DCS_CMD(0x67, 0x36),
> +	_INIT_DCS_CMD(0x68, 0x54),
> +	_INIT_DCS_CMD(0x69, 0x42),
> +	_INIT_DCS_CMD(0x6A, 0x48),
> +	_INIT_DCS_CMD(0x6B, 0x39),
> +	_INIT_DCS_CMD(0x6C, 0x34),
> +	_INIT_DCS_CMD(0x6D, 0x26),
> +	_INIT_DCS_CMD(0x6E, 0x14),
> +	_INIT_DCS_CMD(0x6F, 0x02),
> +	_INIT_DCS_CMD(0x70, 0x7F),
> +	_INIT_DCS_CMD(0x71, 0x61),
> +	_INIT_DCS_CMD(0x72, 0x50),
> +	_INIT_DCS_CMD(0x73, 0x43),
> +	_INIT_DCS_CMD(0x74, 0x3F),
> +	_INIT_DCS_CMD(0x75, 0x32),
> +	_INIT_DCS_CMD(0x76, 0x35),
> +	_INIT_DCS_CMD(0x77, 0x1F),
> +	_INIT_DCS_CMD(0x78, 0x38),
> +	_INIT_DCS_CMD(0x79, 0x36),
> +	_INIT_DCS_CMD(0x7A, 0x36),
> +	_INIT_DCS_CMD(0x7B, 0x54),
> +	_INIT_DCS_CMD(0x7C, 0x42),
> +	_INIT_DCS_CMD(0x7D, 0x48),
> +	_INIT_DCS_CMD(0x7E, 0x39),
> +	_INIT_DCS_CMD(0x7F, 0x34),
> +	_INIT_DCS_CMD(0x80, 0x26),
> +	_INIT_DCS_CMD(0x81, 0x14),
> +	_INIT_DCS_CMD(0x82, 0x02),
> +	_INIT_DCS_CMD(0xE0, 0x02),
> +	_INIT_DCS_CMD(0x00, 0x52),
> +	_INIT_DCS_CMD(0x01, 0x5F),
> +	_INIT_DCS_CMD(0x02, 0x5F),
> +	_INIT_DCS_CMD(0x03, 0x50),
> +	_INIT_DCS_CMD(0x04, 0x77),
> +	_INIT_DCS_CMD(0x05, 0x57),
> +	_INIT_DCS_CMD(0x06, 0x5F),
> +	_INIT_DCS_CMD(0x07, 0x4E),
> +	_INIT_DCS_CMD(0x08, 0x4C),
> +	_INIT_DCS_CMD(0x09, 0x5F),
> +	_INIT_DCS_CMD(0x0A, 0x4A),
> +	_INIT_DCS_CMD(0x0B, 0x48),
> +	_INIT_DCS_CMD(0x0C, 0x5F),
> +	_INIT_DCS_CMD(0x0D, 0x46),
> +	_INIT_DCS_CMD(0x0E, 0x44),
> +	_INIT_DCS_CMD(0x0F, 0x40),
> +	_INIT_DCS_CMD(0x10, 0x5F),
> +	_INIT_DCS_CMD(0x11, 0x5F),
> +	_INIT_DCS_CMD(0x12, 0x5F),
> +	_INIT_DCS_CMD(0x13, 0x5F),
> +	_INIT_DCS_CMD(0x14, 0x5F),
> +	_INIT_DCS_CMD(0x15, 0x5F),
> +	_INIT_DCS_CMD(0x16, 0x53),
> +	_INIT_DCS_CMD(0x17, 0x5F),
> +	_INIT_DCS_CMD(0x18, 0x5F),
> +	_INIT_DCS_CMD(0x19, 0x51),
> +	_INIT_DCS_CMD(0x1A, 0x77),
> +	_INIT_DCS_CMD(0x1B, 0x57),
> +	_INIT_DCS_CMD(0x1C, 0x5F),
> +	_INIT_DCS_CMD(0x1D, 0x4F),
> +	_INIT_DCS_CMD(0x1E, 0x4D),
> +	_INIT_DCS_CMD(0x1F, 0x5F),
> +	_INIT_DCS_CMD(0x20, 0x4B),
> +	_INIT_DCS_CMD(0x21, 0x49),
> +	_INIT_DCS_CMD(0x22, 0x5F),
> +	_INIT_DCS_CMD(0x23, 0x47),
> +	_INIT_DCS_CMD(0x24, 0x45),
> +	_INIT_DCS_CMD(0x25, 0x41),
> +	_INIT_DCS_CMD(0x26, 0x5F),
> +	_INIT_DCS_CMD(0x27, 0x5F),
> +	_INIT_DCS_CMD(0x28, 0x5F),
> +	_INIT_DCS_CMD(0x29, 0x5F),
> +	_INIT_DCS_CMD(0x2A, 0x5F),
> +	_INIT_DCS_CMD(0x2B, 0x5F),
> +	_INIT_DCS_CMD(0x2C, 0x13),
> +	_INIT_DCS_CMD(0x2D, 0x1F),
> +	_INIT_DCS_CMD(0x2E, 0x1F),
> +	_INIT_DCS_CMD(0x2F, 0x01),
> +	_INIT_DCS_CMD(0x30, 0x17),
> +	_INIT_DCS_CMD(0x31, 0x17),
> +	_INIT_DCS_CMD(0x32, 0x1F),
> +	_INIT_DCS_CMD(0x33, 0x0D),
> +	_INIT_DCS_CMD(0x34, 0x0F),
> +	_INIT_DCS_CMD(0x35, 0x1F),
> +	_INIT_DCS_CMD(0x36, 0x05),
> +	_INIT_DCS_CMD(0x37, 0x07),
> +	_INIT_DCS_CMD(0x38, 0x1F),
> +	_INIT_DCS_CMD(0x39, 0x09),
> +	_INIT_DCS_CMD(0x3A, 0x0B),
> +	_INIT_DCS_CMD(0x3B, 0x11),
> +	_INIT_DCS_CMD(0x3C, 0x1F),
> +	_INIT_DCS_CMD(0x3D, 0x1F),
> +	_INIT_DCS_CMD(0x3E, 0x1F),
> +	_INIT_DCS_CMD(0x3F, 0x1F),
> +	_INIT_DCS_CMD(0x40, 0x1F),
> +	_INIT_DCS_CMD(0x41, 0x1F),
> +	_INIT_DCS_CMD(0x42, 0x12),
> +	_INIT_DCS_CMD(0x43, 0x1F),
> +	_INIT_DCS_CMD(0x44, 0x1F),
> +	_INIT_DCS_CMD(0x45, 0x00),
> +	_INIT_DCS_CMD(0x46, 0x17),
> +	_INIT_DCS_CMD(0x47, 0x17),
> +	_INIT_DCS_CMD(0x48, 0x1F),
> +	_INIT_DCS_CMD(0x49, 0x0C),
> +	_INIT_DCS_CMD(0x4A, 0x0E),
> +	_INIT_DCS_CMD(0x4B, 0x1F),
> +	_INIT_DCS_CMD(0x4C, 0x04),
> +	_INIT_DCS_CMD(0x4D, 0x06),
> +	_INIT_DCS_CMD(0x4E, 0x1F),
> +	_INIT_DCS_CMD(0x4F, 0x08),
> +	_INIT_DCS_CMD(0x50, 0x0A),
> +	_INIT_DCS_CMD(0x51, 0x10),
> +	_INIT_DCS_CMD(0x52, 0x1F),
> +	_INIT_DCS_CMD(0x53, 0x1F),
> +	_INIT_DCS_CMD(0x54, 0x1F),
> +	_INIT_DCS_CMD(0x55, 0x1F),
> +	_INIT_DCS_CMD(0x56, 0x1F),
> +	_INIT_DCS_CMD(0x57, 0x1F),
> +	_INIT_DCS_CMD(0x58, 0x40),
> +	_INIT_DCS_CMD(0x5B, 0x10),
> +	_INIT_DCS_CMD(0x5C, 0x06),
> +	_INIT_DCS_CMD(0x5D, 0x40),
> +	_INIT_DCS_CMD(0x5E, 0x00),
> +	_INIT_DCS_CMD(0x5F, 0x00),
> +	_INIT_DCS_CMD(0x60, 0x40),
> +	_INIT_DCS_CMD(0x61, 0x03),
> +	_INIT_DCS_CMD(0x62, 0x04),
> +	_INIT_DCS_CMD(0x63, 0x6C),
> +	_INIT_DCS_CMD(0x64, 0x6C),
> +	_INIT_DCS_CMD(0x65, 0x75),
> +	_INIT_DCS_CMD(0x66, 0x08),
> +	_INIT_DCS_CMD(0x67, 0xB4),
> +	_INIT_DCS_CMD(0x68, 0x08),
> +	_INIT_DCS_CMD(0x69, 0x6C),
> +	_INIT_DCS_CMD(0x6A, 0x6C),
> +	_INIT_DCS_CMD(0x6B, 0x0C),
> +	_INIT_DCS_CMD(0x6D, 0x00),
> +	_INIT_DCS_CMD(0x6E, 0x00),
> +	_INIT_DCS_CMD(0x6F, 0x88),
> +	_INIT_DCS_CMD(0x75, 0xBB),
> +	_INIT_DCS_CMD(0x76, 0x00),
> +	_INIT_DCS_CMD(0x77, 0x05),
> +	_INIT_DCS_CMD(0x78, 0x2A),
> +	_INIT_DCS_CMD(0xE0, 0x04),
> +	_INIT_DCS_CMD(0x00, 0x0E),
> +	_INIT_DCS_CMD(0x02, 0xB3),
> +	_INIT_DCS_CMD(0x09, 0x61),
> +	_INIT_DCS_CMD(0x0E, 0x48),
> +
> +	_INIT_DCS_CMD(0xE0, 0x00),
> +	_INIT_DCS_CMD(0X11),
> +	/* T6: 120ms */
> +	_INIT_DELAY_CMD(120),
> +	_INIT_DCS_CMD(0X29),
> +	_INIT_DELAY_CMD(20),
> +	{},
> +};
> +
> +static inline struct kingdisplay_panel *to_kingdisplay_panel(struct drm_panel *panel)
> +{
> +	return container_of(panel, struct kingdisplay_panel, base);
> +}
> +
> +static int kingdisplay_panel_init_dcs_cmd(struct kingdisplay_panel *kingdisplay)
> +{
> +	struct mipi_dsi_device *dsi = kingdisplay->dsi;
> +	struct drm_panel *panel = &kingdisplay->base;
> +	int i, err = 0;
> +
> +	if (kingdisplay->desc->init_cmds) {
> +		const struct panel_init_cmd *init_cmds = kingdisplay->desc->init_cmds;
> +
> +		for (i = 0; init_cmds[i].len != 0; i++) {
> +			const struct panel_init_cmd *cmd = &init_cmds[i];
> +
> +			switch (cmd->type) {
> +			case DELAY_CMD:
> +				msleep(cmd->data[0]);
> +				err = 0;
> +				break;
> +
> +			case INIT_DCS_CMD:
> +				err = mipi_dsi_dcs_write(dsi, cmd->data[0],
> +							 cmd->len <= 1 ? NULL :
> +							 &cmd->data[1],
> +							 cmd->len - 1);
> +				break;
> +
> +			default:
> +				err = -EINVAL;
> +			}
> +
> +			if (err < 0) {
> +				dev_err(panel->dev,
> +					"failed to write command %u\n", i);
> +				return err;
> +			}
> +		}
> +	}
> +	return 0;
> +}
> +
> +static int kingdisplay_panel_enter_sleep_mode(struct kingdisplay_panel *kingdisplay)
> +{
> +	struct mipi_dsi_device *dsi = kingdisplay->dsi;
> +	int ret;
> +
> +	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
> +
> +	usleep_range(1000, 2000);
> +	ret = mipi_dsi_dcs_set_display_off(dsi);
> +	if (ret < 0)
> +		return ret;
> +
> +	msleep(50);
> +
> +	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static int kingdisplay_panel_disable(struct drm_panel *panel)
> +{
> +	struct kingdisplay_panel *kingdisplay = to_kingdisplay_panel(panel);
> +	int ret;
> +
> +	ret = kingdisplay_panel_enter_sleep_mode(kingdisplay);
> +	if (ret < 0) {
> +		dev_err(panel->dev, "failed to set panel off: %d\n", ret);
> +		return ret;
> +	}
> +
> +	msleep(100);
> +
> +	return 0;
> +}
> +
> +static int kingdisplay_panel_unprepare(struct drm_panel *panel)
> +{
> +	struct kingdisplay_panel *kingdisplay = to_kingdisplay_panel(panel);
> +	int err;
> +
> +	gpiod_set_value_cansleep(kingdisplay->enable_gpio, 0);
> +
> +	/* T15: 2ms */
> +	usleep_range(1000, 2000);
> +
> +	err = regulator_disable(kingdisplay->pp3300);
> +	if (err < 0)
> +		return err;
> +
> +	return 0;
> +}
> +
> +static int kingdisplay_panel_prepare(struct drm_panel *panel)
> +{
> +	struct kingdisplay_panel *kingdisplay = to_kingdisplay_panel(panel);
> +	int ret;
> +
> +	gpiod_set_value(kingdisplay->enable_gpio, 0);
> +
> +	ret = regulator_enable(kingdisplay->pp3300);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* T1: 5ms */
> +	usleep_range(5000, 6000);
> +
> +	if (kingdisplay->desc->lp11_before_reset) {
> +		mipi_dsi_dcs_nop(kingdisplay->dsi);
> +		usleep_range(1000, 2000);
> +	}
> +
> +	/* T2: 10ms, T1 + T2 > 5ms*/
> +	usleep_range(10000, 11000);
> +
> +	gpiod_set_value_cansleep(kingdisplay->enable_gpio, 1);
> +
> +	ret = kingdisplay_panel_init_dcs_cmd(kingdisplay);
> +	if (ret < 0) {
> +		dev_err(panel->dev, "failed to init panel: %d\n", ret);
> +		goto poweroff;
> +	}
> +
> +	return 0;
> +
> +poweroff:
> +	regulator_disable(kingdisplay->pp3300);
> +		/* T6: 2ms */
> +	usleep_range(1000, 2000);
> +	gpiod_set_value(kingdisplay->enable_gpio, 0);
> +
> +	return ret;
> +}
> +
> +static int kingdisplay_panel_enable(struct drm_panel *panel)
> +{
> +	msleep(130);
> +	return 0;
> +}
> +
> +static const struct drm_display_mode kingdisplay_kd101ne3_40ti_default_mode = {
> +	.clock = 70595,
> +	.hdisplay = 800,
> +	.hsync_start = 800 + 30,
> +	.hsync_end = 800 + 30 + 30,
> +	.htotal = 800 + 30 + 30 + 30,
> +	.vdisplay = 1280,
> +	.vsync_start = 1280 + 30,
> +	.vsync_end = 1280 + 30 + 4,
> +	.vtotal = 1280 + 30 + 4 + 8,
> +	.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
> +};
> +
> +static const struct panel_desc kingdisplay_kd101ne3_40ti_desc = {
> +	.modes = &kingdisplay_kd101ne3_40ti_default_mode,
> +	.bpc = 8,
> +	.size = {
> +		.width_mm = 135,
> +		.height_mm = 216,
> +	},
> +	.lanes = 4,
> +	.format = MIPI_DSI_FMT_RGB888,
> +	.mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
> +		      MIPI_DSI_MODE_LPM,
> +	.init_cmds = kingdisplay_kd101ne3_init_cmd,
> +	.lp11_before_reset = true,
> +};
> +
> +static int kingdisplay_panel_get_modes(struct drm_panel *panel,
> +			       struct drm_connector *connector)
> +{
> +	struct kingdisplay_panel *kingdisplay = to_kingdisplay_panel(panel);
> +	const struct drm_display_mode *m = kingdisplay->desc->modes;
> +	struct drm_display_mode *mode;
> +
> +	mode = drm_mode_duplicate(connector->dev, m);
> +	if (!mode) {
> +		dev_err(panel->dev, "failed to add mode %ux%u@%u\n",
> +			m->hdisplay, m->vdisplay, drm_mode_vrefresh(m));
> +		return -ENOMEM;
> +	}
> +
> +	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
> +	drm_mode_set_name(mode);
> +	drm_mode_probed_add(connector, mode);
> +
> +	connector->display_info.width_mm = kingdisplay->desc->size.width_mm;
> +	connector->display_info.height_mm = kingdisplay->desc->size.height_mm;

Please use drm_connector_helper_get_modes_fixed()

> +	connector->display_info.bpc = kingdisplay->desc->bpc;
> +	/*
> +	 * TODO: Remove once all drm drivers call
> +	 * drm_connector_set_orientation_from_panel()

What is your usecase / platform? Are you using drm_bridge_connector? If not, why?

> +	 */
> +	drm_connector_set_panel_orientation(connector, kingdisplay->orientation);
> +
> +	return 1;
> +}
> +
> +static enum drm_panel_orientation kingdisplay_panel_get_orientation(struct drm_panel *panel)
> +{
> +	struct kingdisplay_panel *kingdisplay = to_kingdisplay_panel(panel);
> +
> +	return kingdisplay->orientation;
> +}
> +
> +static const struct drm_panel_funcs kingdisplay_panel_funcs = {
> +	.disable = kingdisplay_panel_disable,
> +	.unprepare = kingdisplay_panel_unprepare,
> +	.prepare = kingdisplay_panel_prepare,
> +	.enable = kingdisplay_panel_enable,
> +	.get_modes = kingdisplay_panel_get_modes,
> +	.get_orientation = kingdisplay_panel_get_orientation,
> +};
> +
> +static int kingdisplay_panel_add(struct kingdisplay_panel *kingdisplay)
> +{
> +	struct device *dev = &kingdisplay->dsi->dev;
> +	int err;
> +
> +	kingdisplay->pp3300 = devm_regulator_get(dev, "pp3300");
> +	if (IS_ERR(kingdisplay->pp3300))
> +		return PTR_ERR(kingdisplay->pp3300);
> +
> +
> +	kingdisplay->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
> +	if (IS_ERR(kingdisplay->enable_gpio)) {
> +		dev_err(dev, "cannot get reset-gpios %ld\n",
> +			PTR_ERR(kingdisplay->enable_gpio));
> +		return PTR_ERR(kingdisplay->enable_gpio);
> +	}
> +
> +	gpiod_set_value(kingdisplay->enable_gpio, 0);
> +
> +	drm_panel_init(&kingdisplay->base, dev, &kingdisplay_panel_funcs,
> +		       DRM_MODE_CONNECTOR_DSI);
> +	err = of_drm_get_panel_orientation(dev->of_node, &kingdisplay->orientation);
> +	if (err < 0) {
> +		dev_err(dev, "%pOF: failed to get orientation %d\n", dev->of_node, err);
> +		return err;
> +	}
> +
> +	err = drm_panel_of_backlight(&kingdisplay->base);
> +	if (err)
> +		return err;
> +
> +	kingdisplay->base.funcs = &kingdisplay_panel_funcs;
> +	kingdisplay->base.dev = &kingdisplay->dsi->dev;
> +
> +	drm_panel_add(&kingdisplay->base);
> +
> +	return 0;
> +}
> +
> +static int kingdisplay_panel_probe(struct mipi_dsi_device *dsi)
> +{
> +	struct kingdisplay_panel *kingdisplay;
> +	int ret;
> +	const struct panel_desc *desc;
> +
> +	kingdisplay = devm_kzalloc(&dsi->dev, sizeof(*kingdisplay), GFP_KERNEL);
> +	if (!kingdisplay)
> +		return -ENOMEM;
> +
> +	desc = of_device_get_match_data(&dsi->dev);
> +	dsi->lanes = desc->lanes;
> +	dsi->format = desc->format;
> +	dsi->mode_flags = desc->mode_flags;
> +	kingdisplay->desc = desc;
> +	kingdisplay->dsi = dsi;
> +	ret = kingdisplay_panel_add(kingdisplay);
> +	if (ret < 0)
> +		return ret;
> +
> +	mipi_dsi_set_drvdata(dsi, kingdisplay);
> +
> +	ret = mipi_dsi_attach(dsi);
> +	if (ret)
> +		drm_panel_remove(&kingdisplay->base);
> +
> +	return ret;
> +}
> +
> +static void kingdisplay_panel_shutdown(struct mipi_dsi_device *dsi)
> +{
> +	struct kingdisplay_panel *kingdisplay = mipi_dsi_get_drvdata(dsi);
> +
> +	drm_panel_disable(&kingdisplay->base);
> +	drm_panel_unprepare(&kingdisplay->base);
> +}
> +
> +static void kingdisplay_panel_remove(struct mipi_dsi_device *dsi)
> +{
> +	struct kingdisplay_panel *kingdisplay = mipi_dsi_get_drvdata(dsi);
> +	int ret;
> +
> +	kingdisplay_panel_shutdown(dsi);
> +
> +	ret = mipi_dsi_detach(dsi);
> +	if (ret < 0)
> +		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", ret);
> +
> +	if (kingdisplay->base.dev)
> +		drm_panel_remove(&kingdisplay->base);

You are adding it unconditionally, so there should be no condition on
removal of the panel.

> +}
> +
> +static const struct of_device_id kingdisplay_of_match[] = {
> +	{ .compatible = "kingdisplay,kd101ne3-40ti",
> +	  .data = &kingdisplay_kd101ne3_40ti_desc
> +	},
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, kingdisplay_of_match);
> +
> +static struct mipi_dsi_driver kingdisplay_panel_driver = {
> +	.driver = {
> +		.name = "panel-kingdisplay-kd101ne3",
> +		.of_match_table = kingdisplay_of_match,
> +	},
> +	.probe = kingdisplay_panel_probe,
> +	.remove = kingdisplay_panel_remove,
> +	.shutdown = kingdisplay_panel_shutdown,
> +};
> +module_mipi_dsi_driver(kingdisplay_panel_driver);
> +
> +MODULE_AUTHOR("Zhaoxiong Lv <lvzhaoxiong@huaqin.corp-partner.google.com>");
> +MODULE_DESCRIPTION("kingdisplay kd101ne3-40ti 800x1280 video mode panel driver");
> +MODULE_LICENSE("GPL v2");
> -- 
> 2.17.1
> 

-- 
With best wishes
Dmitry