Re: [PATCH 08/11] drm/panel: s6e3ha8: add Samsung AMB630QY01 (Google Pixel 3 XL) panel

[Neil Armstrong <neil.armstrong@linaro.org>]

On 9/20/26 13:05, David Heidelberg via B4 Relay wrote:
> From: David Heidelberg <david@ixit.cz>
> 
> The Google Pixel 3 XL (crosshatch) uses a Samsung AMB630QY01 6.3"
> 1440x2960 flexible AMOLED panel, driven by the same S6E3HA8 DDIC as
> the Galaxy S9 panel this driver already supports.
> 
> The init/teardown sequences and timings are taken from the downstream
> dsi-panel-s6e3ha8-dsc-wqhd-cmd.dtsi (Google bluecross kernel). The
> downstream DSI host neither appends EOT packets nor keeps the clock
> lane in HS, so mirror that with the corresponding mode flags, and set
> the RAM window explicitly since the kernel DSI host never sends the
> column/page addresses the downstream one does.
> 
> Unlike the S9 panel, brightness is controlled with standard DCS
> commands (10-bit), so register a backlight device for it. Brightness
> readback is intentionally not implemented: DCS reads wedge the DSI
> host command engine and take the display pipeline down with it.
> 
> Cosmtetics: update Copyright header and add myself.

=> Cosmetics

> 
> Assisted-by: LLM
> Signed-off-by: David Heidelberg <david@ixit.cz>
> ---
>   drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c | 173 +++++++++++++++++++++++++-
>   1 file changed, 168 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c b/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
> index 2591b8c1a7753..e02f1d9f0dcd0 100644
> --- a/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
> +++ b/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
> @@ -1,36 +1,42 @@
>   // SPDX-License-Identifier: GPL-2.0-only
> -//
> -// Generated with linux-mdss-dsi-panel-driver-generator from vendor device tree:
> -//	Copyright (c) 2013, The Linux Foundation. All rights reserved.
> -// Copyright (c) 2024 Dzmitry Sankouski <dsankouski@gmail.com>
> -
> +/*
> + * Generated with linux-mdss-dsi-panel-driver-generator from vendor device tree:
> + *	Copyright (c) 2013, The Linux Foundation. All rights reserved.
> + * Copyright (c) 2024 Dzmitry Sankouski <dsankouski@gmail.com>
> + * Copyright David Heidelberg
> + */
> +
> +#include <linux/backlight.h>
>   #include <linux/delay.h>
>   #include <linux/gpio/consumer.h>
>   #include <linux/module.h>
>   #include <linux/of.h>
>   #include <linux/property.h>
>   #include <linux/regulator/consumer.h>
>   
> +#include <video/mipi_display.h>
> +
>   #include <drm/display/drm_dsc.h>
>   #include <drm/display/drm_dsc_helper.h>
>   #include <drm/drm_mipi_dsi.h>
>   #include <drm/drm_probe_helper.h>
>   #include <drm/drm_panel.h>
>   
>   #include "panel-samsung-dsi.h"
>   
>   struct s6e3ha8_desc {
>   	const struct drm_panel_funcs *funcs;
>   	const struct drm_display_mode *mode;
>   	unsigned long mode_flags;
>   	const struct regulator_bulk_data *supplies;
>   	unsigned int num_supplies;
>   	bool broken_reset_polarity;
> +	bool has_backlight;
>   };
>   
>   struct s6e3ha8 {
>   	struct drm_panel panel;
>   	struct mipi_dsi_device *dsi;
>   	const struct s6e3ha8_desc *desc;
>   	struct drm_dsc_config dsc;
>   	struct gpio_desc *reset_gpio;
> @@ -38,16 +44,23 @@ struct s6e3ha8 {
>   };
>   
>   static const struct regulator_bulk_data s6e3ha8_vddr_supplies[] = {
>   	{ .supply = "vdd3" },
>   	{ .supply = "vci" },
>   	{ .supply = "vddr" },
>   };
>   
> +static const struct regulator_bulk_data s6e3ha8_boost_supplies[] = {
> +	{ .supply = "vdd3" },
> +	{ .supply = "vci" },
> +	{ .supply = "vddpos" },
> +	{ .supply = "vddneg" },
> +};
> +
>   static inline struct s6e3ha8 *to_s6e3ha8(struct drm_panel *panel)
>   {
>   	return container_of(panel, struct s6e3ha8, panel);
>   }
>   
>   #define s6e3ha8_afc_off(ctx) \
>   	mipi_dsi_dcs_write_seq_multi(ctx, 0xe2, 0x00, 0x00)
>   
> @@ -72,16 +85,26 @@ static void s6e3ha8_amb577px01_wqhd_reset(struct s6e3ha8 *priv)
>   	gpiod_set_value_cansleep(priv->reset_gpio, 0);
>   	usleep_range(5000, 6000);
>   	gpiod_set_value_cansleep(priv->reset_gpio, 1);
>   	usleep_range(5000, 6000);
>   	gpiod_set_value_cansleep(priv->reset_gpio, 0);
>   	usleep_range(5000, 6000);
>   }
>   
> +static void s6e3ha8_amb630qy01_reset(struct s6e3ha8 *priv)
> +{
> +	gpiod_set_value_cansleep(priv->reset_gpio, 0);
> +	usleep_range(10000, 11000);
> +	gpiod_set_value_cansleep(priv->reset_gpio, 1);
> +	usleep_range(1000, 2000);
> +	gpiod_set_value_cansleep(priv->reset_gpio, 0);
> +	usleep_range(5000, 6000);
> +}
> +
>   static int s6e3ha8_amb577px01_wqhd_on(struct s6e3ha8 *priv)
>   {
>   	struct mipi_dsi_device *dsi = priv->dsi;
>   	struct mipi_dsi_multi_context ctx = { .dsi = dsi };
>   
>   	dsi->mode_flags |= MIPI_DSI_MODE_LPM;
>   
>   	samsung_dsi_test_key_on_lvl1(&ctx);
> @@ -266,16 +289,146 @@ static const struct s6e3ha8_desc s6e3ha8_amb577px01_wqhd_desc = {
>   	.mode = &s6e3ha8_amb577px01_wqhd_mode,
>   	.mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS |
>   		MIPI_DSI_MODE_VIDEO_NO_HFP | MIPI_DSI_MODE_VIDEO_NO_HBP |
>   		MIPI_DSI_MODE_VIDEO_NO_HSA | MIPI_DSI_MODE_NO_EOT_PACKET,
>   	.supplies = s6e3ha8_vddr_supplies,
>   	.num_supplies = ARRAY_SIZE(s6e3ha8_vddr_supplies),
>   };
>   
> +static int s6e3ha8_amb630qy01_prepare(struct drm_panel *panel)
> +{
> +	struct s6e3ha8 *priv = to_s6e3ha8(panel);
> +	struct mipi_dsi_multi_context ctx = { .dsi = priv->dsi };
> +	struct drm_dsc_picture_parameter_set pps;
> +	int ret;
> +
> +	ret = regulator_bulk_enable(priv->desc->num_supplies, priv->supplies);
> +	if (ret < 0)
> +		return ret;
> +
> +	s6e3ha8_amb630qy01_reset(priv);
> +
> +	mipi_dsi_compression_mode_multi(&ctx, true);
> +
> +	mipi_dsi_dcs_exit_sleep_mode_multi(&ctx);
> +	mipi_dsi_msleep(&ctx, 120);
> +
> +	mipi_dsi_dcs_write_seq_multi(&ctx, MIPI_DCS_WRITE_CONTROL_DISPLAY, 0x20);
> +	mipi_dsi_dcs_set_tear_on_multi(&ctx, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
> +
> +	/*
> +	 * Unlike the downstream DSI host, the kernel one never sends the
> +	 * column/page addresses, so set the RAM window explicitly.
> +	 */
> +	mipi_dsi_dcs_set_column_address_multi(&ctx, 0, 1440 - 1);
> +	mipi_dsi_dcs_set_page_address_multi(&ctx, 0, 2960 - 1);
> +
> +	samsung_dsi_test_key_on_lvl2(&ctx);
> +	mipi_dsi_dcs_write_seq_multi(&ctx, 0xb9,
> +				     0x01, 0xb0, 0x81, 0x09, 0x00, 0x00, 0x00,
> +				     0x11, 0x03); /* TSP HSYNC Setting */
> +	samsung_dsi_test_key_off_lvl2(&ctx);
> +
> +	drm_dsc_pps_payload_pack(&pps, &priv->dsc);
> +	mipi_dsi_picture_parameter_set_multi(&ctx, &pps);
> +
> +	if (ctx.accum_err) {
> +		gpiod_set_value_cansleep(priv->reset_gpio, 1);
> +		regulator_bulk_disable(priv->desc->num_supplies, priv->supplies);
> +	}
> +
> +	return ctx.accum_err;
> +}
> +
> +static int s6e3ha8_amb630qy01_enable(struct drm_panel *panel)
> +{
> +	struct s6e3ha8 *priv = to_s6e3ha8(panel);
> +	struct mipi_dsi_multi_context ctx = { .dsi = priv->dsi };
> +
> +	mipi_dsi_dcs_set_display_on_multi(&ctx);
> +
> +	return ctx.accum_err;
> +}
> +
> +static int s6e3ha8_amb630qy01_disable(struct drm_panel *panel)
> +{
> +	struct s6e3ha8 *priv = to_s6e3ha8(panel);
> +	struct mipi_dsi_multi_context ctx = { .dsi = priv->dsi };
> +
> +	mipi_dsi_dcs_set_display_off_multi(&ctx);
> +	mipi_dsi_msleep(&ctx, 10);
> +	mipi_dsi_dcs_enter_sleep_mode_multi(&ctx);
> +	mipi_dsi_msleep(&ctx, 120);
> +
> +	return ctx.accum_err;
> +}
> +
> +static const struct drm_display_mode s6e3ha8_amb630qy01_mode = {
> +	.clock = (1440 + 116 + 44 + 116) * (2960 + 124 + 120 + 80) * 60 / 1000,
> +	.hdisplay = 1440,
> +	.hsync_start = 1440 + 116,
> +	.hsync_end = 1440 + 116 + 44,
> +	.htotal = 1440 + 116 + 44 + 116,
> +	.vdisplay = 2960,
> +	.vsync_start = 2960 + 124,
> +	.vsync_end = 2960 + 124 + 120,
> +	.vtotal = 2960 + 124 + 120 + 80,
> +	.width_mm = 70,
> +	.height_mm = 144,
> +};
> +
> +static const struct drm_panel_funcs s6e3ha8_amb630qy01_panel_funcs = {
> +	.prepare = s6e3ha8_amb630qy01_prepare,
> +	.unprepare = s6e3ha8_unprepare,
> +	.get_modes = s6e3ha8_get_modes,
> +	.enable = s6e3ha8_amb630qy01_enable,
> +	.disable = s6e3ha8_amb630qy01_disable,
> +};
> +
> +static const struct s6e3ha8_desc s6e3ha8_amb630qy01_desc = {
> +	.funcs = &s6e3ha8_amb630qy01_panel_funcs,
> +	.mode = &s6e3ha8_amb630qy01_mode,
> +	.mode_flags = MIPI_DSI_MODE_LPM | MIPI_DSI_CLOCK_NON_CONTINUOUS |
> +		      MIPI_DSI_MODE_NO_EOT_PACKET,
> +	.supplies = s6e3ha8_boost_supplies,
> +	.num_supplies = ARRAY_SIZE(s6e3ha8_boost_supplies),
> +	.has_backlight = true,
> +};
> +
> +static int s6e3ha8_bl_update_status(struct backlight_device *bl)
> +{
> +	struct mipi_dsi_device *dsi = bl_get_data(bl);
> +	u16 brightness = backlight_get_brightness(bl);
> +
> +	return mipi_dsi_dcs_set_display_brightness_large(dsi, brightness);
> +}
> +
> +/*
> + * No .get_brightness: DCS reads wedge the DSI host command engine and
> + * take the whole display pipeline down with it.
> + */
> +static const struct backlight_ops s6e3ha8_bl_ops = {
> +	.update_status = s6e3ha8_bl_update_status,
> +};
> +
> +static struct backlight_device *
> +s6e3ha8_create_backlight(struct mipi_dsi_device *dsi)
> +{
> +	struct device *dev = &dsi->dev;
> +	const struct backlight_properties props = {
> +		.type = BACKLIGHT_RAW,
> +		.brightness = 512,
> +		.max_brightness = 1023,
> +	};
> +
> +	return devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
> +					      &s6e3ha8_bl_ops, &props);
> +}
> +
>   static int s6e3ha8_probe(struct mipi_dsi_device *dsi)
>   {
>   	struct device *dev = &dsi->dev;
>   	const struct s6e3ha8_desc *desc;
>   	struct s6e3ha8 *priv;
>   	int ret;
>   
>   	desc = device_get_match_data(dev);
> @@ -308,16 +461,23 @@ static int s6e3ha8_probe(struct mipi_dsi_device *dsi)
>   	mipi_dsi_set_drvdata(dsi, priv);
>   
>   	dsi->lanes = 4;
>   	dsi->format = MIPI_DSI_FMT_RGB888;
>   	dsi->mode_flags = priv->desc->mode_flags;
>   
>   	priv->panel.prepare_prev_first = true;
>   
> +	if (priv->desc->has_backlight) {
> +		priv->panel.backlight = s6e3ha8_create_backlight(dsi);
> +		if (IS_ERR(priv->panel.backlight))
> +			return dev_err_probe(dev, PTR_ERR(priv->panel.backlight),
> +					     "Failed to create backlight\n");
> +	}
> +
>   	ret = devm_drm_panel_add(dev, &priv->panel);
>   	if (ret)
>   		return ret;
>   
>   	/* This panel only supports DSC; unconditionally enable it */
>   	dsi->dsc = &priv->dsc;
>   
>   	priv->dsc.dsc_version_major = 1;
> @@ -343,16 +503,19 @@ static int s6e3ha8_probe(struct mipi_dsi_device *dsi)
>   static const struct of_device_id s6e3ha8_of_match[] = {
>   	{
>   		/* deprecated */
>   		.compatible = "samsung,s6e3ha8",
>   		.data = &s6e3ha8_amb577px01_wqhd_desc_legacy,
>   	}, {
>   		.compatible = "samsung,s6e3ha8-amb577px01",
>   		.data = &s6e3ha8_amb577px01_wqhd_desc,
> +	}, {
> +		.compatible = "samsung,s6e3ha8-amb630qy01",
> +		.data = &s6e3ha8_amb630qy01_desc,
>   	},
>   	{ /* sentinel */ }
>   };
>   MODULE_DEVICE_TABLE(of, s6e3ha8_of_match);
>   
>   static struct mipi_dsi_driver s6e3ha8_driver = {
>   	.probe = s6e3ha8_probe,
>   	.driver = {
> 

With typo fixed:
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>

Thanks,
Neil