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References: <20210304092133.21717-1-jagan@amarulasolutions.com> <20210304092133.21717-2-jagan@amarulasolutions.com>
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From:   Robert Foss <robert.foss@linaro.org>
Date:   Fri, 5 Mar 2021 10:16:37 +0100
Message-ID: <CAG3jFyue4LUPuEHq-k=VjSDMSdG7DEFHMaqYBMZFdXorNA5q+Q@mail.gmail.com>
Subject: Re: [PATCH v4 2/2] drm: bridge: Add Chipone ICN6211 MIPI-DSI to RGB bridge
To:     Jagan Teki <jagan@amarulasolutions.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Andrzej Hajda <a.hajda@samsung.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@siol.net>,
        Sam Ravnborg <sam@ravnborg.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>, linux-amarula@amarulasolutions.com
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hey Jagan,

This patch also looks good to me.

Reviewed-by: Robert Foss <robert.foss@linaro.org>

On Thu, 4 Mar 2021 at 10:22, Jagan Teki <jagan@amarulasolutions.com> wrote:
>
> ICN6211 is MIPI-DSI to RGB Converter bridge from Chipone.
>
> It has a flexible configuration of MIPI DSI signal input and
> produce RGB565, RGB666, RGB888 output format.
>
> Add bridge driver for it.
>
> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> ---
> Changes for v4:
> - added regulators
> - replace reset with EN
> - fixed warnings pointed by Robert
> Changes for v3:
> - updated the driver to inline with new drm bridge style
>
>  MAINTAINERS                              |   1 +
>  drivers/gpu/drm/bridge/Kconfig           |  13 +
>  drivers/gpu/drm/bridge/Makefile          |   1 +
>  drivers/gpu/drm/bridge/chipone-icn6211.c | 293 +++++++++++++++++++++++
>  4 files changed, 308 insertions(+)
>  create mode 100644 drivers/gpu/drm/bridge/chipone-icn6211.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 065cbdc889d3..9c59402e51bc 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -5533,6 +5533,7 @@ DRM DRIVER FOR CHIPONE ICN6211 MIPI-DSI to RGB CONVERTER BRIDGE
>  M:     Jagan Teki <jagan@amarulasolutions.com>
>  S:     Maintained
>  F:     Documentation/devicetree/bindings/display/bridge/chipone,icn6211.yaml
> +F:     drivers/gpu/drm/bridge/chipone-icn6211.c
>
>  DRM DRIVER FOR FARADAY TVE200 TV ENCODER
>  M:     Linus Walleij <linus.walleij@linaro.org>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index e4110d6ca7b3..330ee70ed746 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -27,6 +27,19 @@ config DRM_CDNS_DSI
>           Support Cadence DPI to DSI bridge. This is an internal
>           bridge and is meant to be directly embedded in a SoC.
>
> +config DRM_CHIPONE_ICN6211
> +       tristate "Chipone ICN6211 MIPI-DSI/RGB Converter bridge"
> +       depends on OF
> +       select DRM_MIPI_DSI
> +       select DRM_PANEL_BRIDGE
> +       help
> +         ICN6211 is MIPI-DSI/RGB Converter bridge from chipone.
> +
> +         It has a flexible configuration of MIPI DSI signal input
> +         and produce RGB565, RGB666, RGB888 output format.
> +
> +         If in doubt, say "N".
> +
>  config DRM_CHRONTEL_CH7033
>         tristate "Chrontel CH7033 Video Encoder"
>         depends on OF
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index 86e7acc76f8d..3eb84b638988 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -1,5 +1,6 @@
>  # SPDX-License-Identifier: GPL-2.0
>  obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
> +obj-$(CONFIG_DRM_CHIPONE_ICN6211) += chipone-icn6211.o
>  obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o
>  obj-$(CONFIG_DRM_DISPLAY_CONNECTOR) += display-connector.o
>  obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o
> diff --git a/drivers/gpu/drm/bridge/chipone-icn6211.c b/drivers/gpu/drm/bridge/chipone-icn6211.c
> new file mode 100644
> index 000000000000..a6151db95586
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/chipone-icn6211.c
> @@ -0,0 +1,293 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2020 Amarula Solutions(India)
> + * Author: Jagan Teki <jagan@amarulasolutions.com>
> + */
> +
> +#include <drm/drm_of.h>
> +#include <drm/drm_print.h>
> +#include <drm/drm_mipi_dsi.h>
> +
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <video/mipi_display.h>
> +
> +#define HACTIVE_LI             0x20
> +#define VACTIVE_LI             0x21
> +#define VACTIVE_HACTIVE_HI     0x22
> +#define HFP_LI                 0x23
> +#define HSYNC_LI               0x24
> +#define HBP_LI                 0x25
> +#define HFP_HSW_HBP_HI         0x26
> +#define VFP                    0x27
> +#define VSYNC                  0x28
> +#define VBP                    0x29
> +
> +struct chipone {
> +       struct device *dev;
> +       struct drm_bridge bridge;
> +       struct drm_bridge *panel_bridge;
> +       struct gpio_desc *enable_gpio;
> +       struct regulator *vdd1;
> +       struct regulator *vdd2;
> +       struct regulator *vdd3;
> +};
> +
> +static inline struct chipone *bridge_to_chipone(struct drm_bridge *bridge)
> +{
> +       return container_of(bridge, struct chipone, bridge);
> +}
> +
> +static struct drm_display_mode *bridge_to_mode(struct drm_bridge *bridge)
> +{
> +       return &bridge->encoder->crtc->state->adjusted_mode;
> +}
> +
> +static inline int chipone_dsi_write(struct chipone *icn,  const void *seq,
> +                                   size_t len)
> +{
> +       struct mipi_dsi_device *dsi = to_mipi_dsi_device(icn->dev);
> +
> +       return mipi_dsi_generic_write(dsi, seq, len);
> +}
> +
> +#define ICN6211_DSI(icn, seq...)                               \
> +       {                                                       \
> +               const u8 d[] = { seq };                         \
> +               chipone_dsi_write(icn, d, ARRAY_SIZE(d));       \
> +       }
> +
> +static void chipone_enable(struct drm_bridge *bridge)
> +{
> +       struct chipone *icn = bridge_to_chipone(bridge);
> +       struct drm_display_mode *mode = bridge_to_mode(bridge);
> +
> +       ICN6211_DSI(icn, 0x7a, 0xc1);
> +
> +       ICN6211_DSI(icn, HACTIVE_LI, mode->hdisplay & 0xff);
> +
> +       ICN6211_DSI(icn, VACTIVE_LI, mode->vdisplay & 0xff);
> +
> +       /**
> +        * lsb nibble: 2nd nibble of hdisplay
> +        * msb nibble: 2nd nibble of vdisplay
> +        */
> +       ICN6211_DSI(icn, VACTIVE_HACTIVE_HI,
> +                   ((mode->hdisplay >> 8) & 0xf) |
> +                   (((mode->vdisplay >> 8) & 0xf) << 4));
> +
> +       ICN6211_DSI(icn, HFP_LI, mode->hsync_start - mode->hdisplay);
> +
> +       ICN6211_DSI(icn, HSYNC_LI, mode->hsync_end - mode->hsync_start);
> +
> +       ICN6211_DSI(icn, HBP_LI, mode->htotal - mode->hsync_end);
> +
> +       ICN6211_DSI(icn, HFP_HSW_HBP_HI, 0x00);
> +
> +       ICN6211_DSI(icn, VFP, mode->vsync_start - mode->vdisplay);
> +
> +       ICN6211_DSI(icn, VSYNC, mode->vsync_end - mode->vsync_start);
> +
> +       ICN6211_DSI(icn, VBP, mode->vtotal - mode->vsync_end);
> +
> +       /* dsi specific sequence */
> +       ICN6211_DSI(icn, MIPI_DCS_SET_TEAR_OFF, 0x80);
> +       ICN6211_DSI(icn, MIPI_DCS_SET_ADDRESS_MODE, 0x28);
> +       ICN6211_DSI(icn, 0xb5, 0xa0);
> +       ICN6211_DSI(icn, 0x5c, 0xff);
> +       ICN6211_DSI(icn, MIPI_DCS_SET_COLUMN_ADDRESS, 0x01);
> +       ICN6211_DSI(icn, MIPI_DCS_GET_POWER_SAVE, 0x92);
> +       ICN6211_DSI(icn, 0x6b, 0x71);
> +       ICN6211_DSI(icn, 0x69, 0x2b);
> +       ICN6211_DSI(icn, MIPI_DCS_ENTER_SLEEP_MODE, 0x40);
> +       ICN6211_DSI(icn, MIPI_DCS_EXIT_SLEEP_MODE, 0x98);
> +
> +       /* icn6211 specific sequence */
> +       ICN6211_DSI(icn, 0xb6, 0x20);
> +       ICN6211_DSI(icn, 0x51, 0x20);
> +       ICN6211_DSI(icn, 0x09, 0x10);
> +
> +       usleep_range(10000, 11000);
> +}
> +
> +static void chipone_pre_enable(struct drm_bridge *bridge)
> +{
> +       struct chipone *icn = bridge_to_chipone(bridge);
> +       int ret;
> +
> +       if (icn->vdd1) {
> +               ret = regulator_enable(icn->vdd1);
> +               if (ret)
> +                       DRM_DEV_ERROR(icn->dev,
> +                                     "failed to enable VDD1 regulator: %d\n", ret);
> +       }
> +
> +       if (icn->vdd2) {
> +               ret = regulator_enable(icn->vdd2);
> +               if (ret)
> +                       DRM_DEV_ERROR(icn->dev,
> +                                     "failed to enable VDD2 regulator: %d\n", ret);
> +       }
> +
> +       if (icn->vdd3) {
> +               ret = regulator_enable(icn->vdd3);
> +               if (ret)
> +                       DRM_DEV_ERROR(icn->dev,
> +                                     "failed to enable VDD3 regulator: %d\n", ret);
> +       }
> +
> +       gpiod_set_value(icn->enable_gpio, 1);
> +
> +       usleep_range(10000, 11000);
> +}
> +
> +static void chipone_post_disable(struct drm_bridge *bridge)
> +{
> +       struct chipone *icn = bridge_to_chipone(bridge);
> +
> +       if (icn->vdd1)
> +               regulator_disable(icn->vdd1);
> +
> +       if (icn->vdd2)
> +               regulator_disable(icn->vdd2);
> +
> +       if (icn->vdd3)
> +               regulator_disable(icn->vdd3);
> +
> +       gpiod_set_value(icn->enable_gpio, 0);
> +}
> +
> +static int chipone_attach(struct drm_bridge *bridge, enum drm_bridge_attach_flags flags)
> +{
> +       struct chipone *icn = bridge_to_chipone(bridge);
> +
> +       return drm_bridge_attach(bridge->encoder, icn->panel_bridge, bridge, flags);
> +}
> +
> +static const struct drm_bridge_funcs chipone_bridge_funcs = {
> +       .attach = chipone_attach,
> +       .post_disable = chipone_post_disable,
> +       .pre_enable = chipone_pre_enable,
> +       .enable = chipone_enable,
> +};
> +
> +static int chipone_parse_dt(struct chipone *icn)
> +{
> +       struct device *dev = icn->dev;
> +       struct drm_panel *panel;
> +       int ret;
> +
> +       icn->vdd1 = devm_regulator_get_optional(dev, "vdd1");
> +       if (IS_ERR(icn->vdd1)) {
> +               ret = PTR_ERR(icn->vdd1);
> +               if (ret == -EPROBE_DEFER)
> +                       return -EPROBE_DEFER;
> +               icn->vdd1 = NULL;
> +               DRM_DEV_DEBUG(dev, "failed to get VDD1 regulator: %d\n", ret);
> +       }
> +
> +       icn->vdd2 = devm_regulator_get_optional(dev, "vdd2");
> +       if (IS_ERR(icn->vdd2)) {
> +               ret = PTR_ERR(icn->vdd2);
> +               if (ret == -EPROBE_DEFER)
> +                       return -EPROBE_DEFER;
> +               icn->vdd2 = NULL;
> +               DRM_DEV_DEBUG(dev, "failed to get VDD2 regulator: %d\n", ret);
> +       }
> +
> +       icn->vdd3 = devm_regulator_get_optional(dev, "vdd3");
> +       if (IS_ERR(icn->vdd3)) {
> +               ret = PTR_ERR(icn->vdd3);
> +               if (ret == -EPROBE_DEFER)
> +                       return -EPROBE_DEFER;
> +               icn->vdd3 = NULL;
> +               DRM_DEV_DEBUG(dev, "failed to get VDD3 regulator: %d\n", ret);
> +       }
> +
> +       icn->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
> +       if (IS_ERR(icn->enable_gpio)) {
> +               DRM_DEV_ERROR(dev, "failed to get enable GPIO\n");
> +               return PTR_ERR(icn->enable_gpio);
> +       }
> +
> +       ret = drm_of_find_panel_or_bridge(dev->of_node, 1, 0, &panel, NULL);
> +       if (ret)
> +               return ret;
> +
> +       icn->panel_bridge = devm_drm_panel_bridge_add(dev, panel);
> +       if (IS_ERR(icn->panel_bridge))
> +               return PTR_ERR(icn->panel_bridge);
> +
> +       return 0;
> +}
> +
> +static int chipone_probe(struct mipi_dsi_device *dsi)
> +{
> +       struct device *dev = &dsi->dev;
> +       struct chipone *icn;
> +       int ret;
> +
> +       icn = devm_kzalloc(dev, sizeof(struct chipone), GFP_KERNEL);
> +       if (!icn)
> +               return -ENOMEM;
> +
> +       mipi_dsi_set_drvdata(dsi, icn);
> +       icn->dev = dev;
> +
> +       ret = chipone_parse_dt(icn);
> +       if (ret)
> +               return ret;
> +
> +       icn->bridge.funcs = &chipone_bridge_funcs;
> +       icn->bridge.type = DRM_MODE_CONNECTOR_DPI;
> +       icn->bridge.of_node = dev->of_node;
> +
> +       drm_bridge_add(&icn->bridge);
> +
> +       dsi->lanes = 4;
> +       dsi->format = MIPI_DSI_FMT_RGB888;
> +       dsi->mode_flags = MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
> +
> +       ret = mipi_dsi_attach(dsi);
> +       if (ret < 0) {
> +               drm_bridge_remove(&icn->bridge);
> +               dev_err(dev, "failed to attach dsi\n");
> +       }
> +
> +       return ret;
> +}
> +
> +static int chipone_remove(struct mipi_dsi_device *dsi)
> +{
> +       struct chipone *icn = mipi_dsi_get_drvdata(dsi);
> +
> +       mipi_dsi_detach(dsi);
> +       drm_bridge_remove(&icn->bridge);
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id chipone_of_match[] = {
> +       { .compatible = "chipone,icn6211", },
> +       { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, chipone_of_match);
> +
> +static struct mipi_dsi_driver chipone_driver = {
> +       .probe = chipone_probe,
> +       .remove = chipone_remove,
> +       .driver = {
> +               .name = "chipone-icn6211",
> +               .owner = THIS_MODULE,
> +               .of_match_table = chipone_of_match,
> +       },
> +};
> +module_mipi_dsi_driver(chipone_driver);
> +
> +MODULE_AUTHOR("Jagan Teki <jagan@amarulasolutions.com>");
> +MODULE_DESCRIPTION("Chipone ICN6211 MIPI-DSI to RGB Converter Bridge");
> +MODULE_LICENSE("GPL");
> --
> 2.25.1
>