[PATCH 0/3] drm/panel: visionox-rm69299: Add backlight support and small fixes

[PATCH 0/3] drm/panel: visionox-rm69299: Add backlight support and small fixes

[Guido Günther]

This adds optional backlight support via DSI commands. If
a max_brightness is set in the panel description the backlight
is created.

While at that we fold in the already sent out clock fix and
a fix that prevents us from clearing all mode flags when we
only want HS mode.

Signed-off-by: Guido Günther <agx@sigxcpu.org>
---
Guido Günther (3):
      drm/panel: visionox-rm69299: Fix clock frequency for SHIFT6mq
      drm/panel: visionox-rm69299: Don't clear all mode flags
      drm/panel: visionox-rm69299: Add backlight support

 drivers/gpu/drm/panel/panel-visionox-rm69299.c | 71 +++++++++++++++++++++++++-
 1 file changed, 69 insertions(+), 2 deletions(-)
---
base-commit: b320789d6883cc00ac78ce83bccbfe7ed58afcf0
change-id: 20250901-shift6mq-panel-959b3087ecd2

Best regards,
-- 
Guido Günther <agx@sigxcpu.org>

[PATCH 1/3] drm/panel: visionox-rm69299: Fix clock frequency for SHIFT6mq

[Guido Günther]

Make the clock frequency match what the sdm845 downstream kernel
uses. Otherwise the panel stays black.

Signed-off-by: Guido Günther <agx@sigxcpu.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
---
 drivers/gpu/drm/panel/panel-visionox-rm69299.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-visionox-rm69299.c b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
index 909c280eab1fb408a713d84051a1afbb252c45e8..e65697ce6f51c7d64b786da18cf44b16de5d6919 100644
--- a/drivers/gpu/drm/panel/panel-visionox-rm69299.c
+++ b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
@@ -247,7 +247,7 @@ static const struct drm_display_mode visionox_rm69299_1080x2248_60hz = {
 };
 
 static const struct drm_display_mode visionox_rm69299_1080x2160_60hz = {
-	.clock = 158695,
+	.clock = 149360,
 	.hdisplay = 1080,
 	.hsync_start = 1080 + 26,
 	.hsync_end = 1080 + 26 + 2,

-- 
2.51.0

[PATCH 2/3] drm/panel: visionox-rm69299: Don't clear all mode flags

[Guido Günther]

Don't clear all mode flags. We only want to maek sure we use HS mode
during unprepare.

Signed-off-by: Guido Günther <agx@sigxcpu.org>
---
 drivers/gpu/drm/panel/panel-visionox-rm69299.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-visionox-rm69299.c b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
index e65697ce6f51c7d64b786da18cf44b16de5d6919..2216d38366ea37368d15480f9d8a8ccbfe77ba3b 100644
--- a/drivers/gpu/drm/panel/panel-visionox-rm69299.c
+++ b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
@@ -192,7 +192,7 @@ static int visionox_rm69299_unprepare(struct drm_panel *panel)
 	struct visionox_rm69299 *ctx = panel_to_ctx(panel);
 	struct mipi_dsi_multi_context dsi_ctx = { .dsi = ctx->dsi };
 
-	ctx->dsi->mode_flags = 0;
+	ctx->dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
 
 	mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
 

-- 
2.51.0

[PATCH 3/3] drm/panel: visionox-rm69299: Add backlight support

[Guido Günther]

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

Signed-off-by: Guido Günther <agx@sigxcpu.org>
---
 drivers/gpu/drm/panel/panel-visionox-rm69299.c | 67 ++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/drivers/gpu/drm/panel/panel-visionox-rm69299.c b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
index 2216d38366ea37368d15480f9d8a8ccbfe77ba3b..5e5ff6056c80e67a5bf8fe4911cdbc588db5d03b 100644
--- a/drivers/gpu/drm/panel/panel-visionox-rm69299.c
+++ b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
@@ -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[] = {

-- 
2.51.0

Re: [PATCH 2/3] drm/panel: visionox-rm69299: Don't clear all mode flags

[Neil Armstrong]

On 01/09/2025 16:22, Guido Günther wrote:
> Don't clear all mode flags. We only want to maek sure we use HS mode
> during unprepare.
> 
> Signed-off-by: Guido Günther <agx@sigxcpu.org>
> ---
>   drivers/gpu/drm/panel/panel-visionox-rm69299.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/panel/panel-visionox-rm69299.c b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
> index e65697ce6f51c7d64b786da18cf44b16de5d6919..2216d38366ea37368d15480f9d8a8ccbfe77ba3b 100644
> --- a/drivers/gpu/drm/panel/panel-visionox-rm69299.c
> +++ b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
> @@ -192,7 +192,7 @@ static int visionox_rm69299_unprepare(struct drm_panel *panel)
>   	struct visionox_rm69299 *ctx = panel_to_ctx(panel);
>   	struct mipi_dsi_multi_context dsi_ctx = { .dsi = ctx->dsi };
>   
> -	ctx->dsi->mode_flags = 0;
> +	ctx->dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
>   
>   	mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
>   
> 

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

Re: [PATCH 3/3] drm/panel: visionox-rm69299: Add backlight support

[Neil Armstrong]

On 01/09/2025 16:22, Guido Günther wrote:
> The shift6mq's variant supports controlling the backlight via DSI
> commands. Use that if a max_brightness is set in the device specific
> data.
> 
> Signed-off-by: Guido Günther <agx@sigxcpu.org>
> ---
>   drivers/gpu/drm/panel/panel-visionox-rm69299.c | 67 ++++++++++++++++++++++++++
>   1 file changed, 67 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panel/panel-visionox-rm69299.c b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
> index 2216d38366ea37368d15480f9d8a8ccbfe77ba3b..5e5ff6056c80e67a5bf8fe4911cdbc588db5d03b 100644
> --- a/drivers/gpu/drm/panel/panel-visionox-rm69299.c
> +++ b/drivers/gpu/drm/panel/panel-visionox-rm69299.c
> @@ -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[] = {
> 

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

Re: [PATCH 3/3] drm/panel: visionox-rm69299: Add backlight support

[kernel test robot]

Hi Guido,

kernel test robot noticed the following build warnings:

[auto build test WARNING on b320789d6883cc00ac78ce83bccbfe7ed58afcf0]

url:    https://github.com/intel-lab-lkp/linux/commits/Guido-G-nther/drm-panel-visionox-rm69299-Fix-clock-frequency-for-SHIFT6mq/20250901-222400
base:   b320789d6883cc00ac78ce83bccbfe7ed58afcf0
patch link:    https://lore.kernel.org/r/20250901-shift6mq-panel-v1-3-444b4abbfaea%40sigxcpu.org
patch subject: [PATCH 3/3] drm/panel: visionox-rm69299: Add backlight support
config: x86_64-randconfig-123-20250902 (https://download.01.org/0day-ci/archive/20250902/202509021907.mZZ38HtR-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14+deb12u1) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250902/202509021907.mZZ38HtR-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509021907.mZZ38HtR-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> drivers/gpu/drm/panel/panel-visionox-rm69299.c:341:24: sparse: sparse: Using plain integer as NULL pointer
   drivers/gpu/drm/panel/panel-visionox-rm69299.c:411:42: sparse: sparse: symbol 'visionox_rm69299_1080p_display_desc' was not declared. Should it be static?
   drivers/gpu/drm/panel/panel-visionox-rm69299.c:417:42: sparse: sparse: symbol 'visionox_rm69299_shift_desc' was not declared. Should it be static?

vim +341 drivers/gpu/drm/panel/panel-visionox-rm69299.c

   329	
   330	static struct backlight_device *
   331	visionox_rm69299_create_backlight(struct visionox_rm69299 *ctx)
   332	{
   333		struct device *dev = &ctx->dsi->dev;
   334		const struct backlight_properties props = {
   335			.type = BACKLIGHT_RAW,
   336			.brightness = ctx->desc->initial_brightness,
   337			.max_brightness = ctx->desc->max_brightness,
   338		};
   339	
   340		if (!ctx->desc->max_brightness)
 > 341			return 0;
   342	
   343		return devm_backlight_device_register(dev, dev_name(dev), dev, ctx->dsi,
   344						      &visionox_rm69299_bl_ops,
   345						      &props);
   346	}
   347	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki