Commit 7911d8ca authored by Guido Günther's avatar Guido Günther Committed by Neil Armstrong
Browse files

drm/panel: visionox-rm69299: Add backlight support 



The shift6mq's variant supports controlling the backlight via DSI
commands. Use that if a max_brightness is set in the device specific
data.

Reviewed-by: default avatarNeil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: default avatarGuido Günther <agx@sigxcpu.org>
Reviewed-by: default avatarDmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: default avatarNeil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250910-shift6mq-panel-v3-3-a7729911afb9@sigxcpu.org
parent 39144b61

drivers/gpu/drm/panel/panel-visionox-rm69299.c

+67 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
 * Copyright (c) 2019, The Linux Foundation. All rights reserved.

 */



#include <linux/backlight.h>

#include <linux/delay.h>

#include <linux/module.h>

#include <linux/property.h>
@@ -20,6 +21,8 @@ struct visionox_rm69299_panel_desc { 
	const struct drm_display_mode *mode;

	const u8 *init_seq;

	unsigned int init_seq_len;

	int max_brightness;

	int initial_brightness;

};



struct visionox_rm69299 {
@@ -285,6 +288,63 @@ static const struct drm_panel_funcs visionox_rm69299_drm_funcs = { 
	.get_modes = visionox_rm69299_get_modes,

};



static int visionox_rm69299_bl_get_brightness(struct backlight_device *bl)

{

	struct mipi_dsi_device *dsi = bl_get_data(bl);

	u16 brightness;

	int ret;



	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;



	ret = mipi_dsi_dcs_get_display_brightness(dsi, &brightness);

	if (ret < 0)

		return ret;



	dsi->mode_flags |= MIPI_DSI_MODE_LPM;



	return brightness;

}



static int visionox_rm69299_bl_update_status(struct backlight_device *bl)

{

	struct mipi_dsi_device *dsi = bl_get_data(bl);

	u16 brightness = backlight_get_brightness(bl);

	int ret;



	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;



	ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness);

	if (ret < 0)

		return ret;



	dsi->mode_flags |= MIPI_DSI_MODE_LPM;



	return 0;

}



static const struct backlight_ops visionox_rm69299_bl_ops = {

	.update_status = visionox_rm69299_bl_update_status,

	.get_brightness = visionox_rm69299_bl_get_brightness,

};



static struct backlight_device *

visionox_rm69299_create_backlight(struct visionox_rm69299 *ctx)

{

	struct device *dev = &ctx->dsi->dev;

	const struct backlight_properties props = {

		.type = BACKLIGHT_RAW,

		.brightness = ctx->desc->initial_brightness,

		.max_brightness = ctx->desc->max_brightness,

	};



	if (!ctx->desc->max_brightness)

		return 0;



	return devm_backlight_device_register(dev, dev_name(dev), dev, ctx->dsi,

					      &visionox_rm69299_bl_ops,

					      &props);

}



static int visionox_rm69299_probe(struct mipi_dsi_device *dsi)

{

	struct device *dev = &dsi->dev;
@@ -316,6 +376,11 @@ static int visionox_rm69299_probe(struct mipi_dsi_device *dsi) 
		return PTR_ERR(ctx->reset_gpio);

	}



	ctx->panel.backlight = visionox_rm69299_create_backlight(ctx);

	if (IS_ERR(ctx->panel.backlight))

		return dev_err_probe(dev, PTR_ERR(ctx->panel.backlight),

				     "Failed to create backlight\n");



	drm_panel_add(&ctx->panel);



	dsi->lanes = 4;
@@ -353,6 +418,8 @@ const struct visionox_rm69299_panel_desc visionox_rm69299_shift_desc = { 
	.mode = &visionox_rm69299_1080x2160_60hz,

	.init_seq = (const u8 *)visionox_rm69299_1080x2160_60hz_init_seq,

	.init_seq_len = ARRAY_SIZE(visionox_rm69299_1080x2160_60hz_init_seq),

	.max_brightness = 255,

	.initial_brightness = 50,

};



static const struct of_device_id visionox_rm69299_of_match[] = {