[PATCH v2 0/2] Add mode_valid hook for sii902x bridge

[PATCH v2 0/2] Add mode_valid hook for sii902x bridge

[Jayesh Choudhary]

Currently, there are no check to validate the modes in the bridge.
Add pixel clock check to validate the modes that the bridge can support.

Also add the mode_valid hook in drm_bridge_funcs structure to take care
of the case when the encoder attaches the bridge chain with the
DRM_BRIDGE_ATTACH_NO_CONNECTOR flag in which case, the connector is not
initialized in the bridge's attach call.

Also add this check to the atomic_check call as suggested by Maxime in
v1 patch.

Changelog v1->v2:
- Add KHZ suffix in the macros to be more clear
- Add the hook for drm_bridge_funcs as well
- Add check in atomic_check dunction call (in a separate patch)

v1 patch:
<https://lore.kernel.org/all/20240408081435.216927-1-j-choudhary@ti.com/>

Jayesh Choudhary (2):
  drm/bridge: sii902x: Fix mode_valid hook
  drm/bridge: Add pixel clock check in atomic_check

 drivers/gpu/drm/bridge/sii902x.c | 43 ++++++++++++++++++++++++++++++--
 1 file changed, 41 insertions(+), 2 deletions(-)

-- 
2.25.1

[PATCH v2 1/2] drm/bridge: sii902x: Fix mode_valid hook

[Jayesh Choudhary]

Currently, mode_valid hook returns all mode as valid and it is
defined only in drm_connector_helper_funcs. With the introduction of
'DRM_BRIDGE_ATTACH_NO_CONNECTOR', connector is not initialized in
bridge_attach call for cases when the encoder has this flag enabled.
So add the mode_valid hook in drm_bridge_funcs as well with proper
clock checks for maximum and minimum pixel clock supported by the
bridge.

Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
---
 drivers/gpu/drm/bridge/sii902x.c | 38 ++++++++++++++++++++++++++++++--
 1 file changed, 36 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 2fbeda9025bf..ef7c3ab3386c 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -163,6 +163,14 @@
 
 #define SII902X_AUDIO_PORT_INDEX		3
 
+/*
+ * The maximum resolution supported by the HDMI bridge is 1080p@60Hz
+ * and 1920x1200 requiring a pixel clock of 165MHz and the minimum
+ * resolution supported is 480p@60Hz requiring a pixel clock of 25MHz
+ */
+#define SII902X_MIN_PIXEL_CLOCK_KHZ		25000
+#define SII902X_MAX_PIXEL_CLOCK_KHZ		165000
+
 struct sii902x {
 	struct i2c_client *i2c;
 	struct regmap *regmap;
@@ -310,12 +318,26 @@ static int sii902x_get_modes(struct drm_connector *connector)
 	return num;
 }
 
+static enum
+drm_mode_status sii902x_validate(struct sii902x *sii902x,
+				 const struct drm_display_mode *mode)
+{
+	if (mode->clock < SII902X_MIN_PIXEL_CLOCK_KHZ)
+		return MODE_CLOCK_LOW;
+
+	if (mode->clock > SII902X_MAX_PIXEL_CLOCK_KHZ)
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
 static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
 					       struct drm_display_mode *mode)
 {
-	/* TODO: check mode */
+	struct sii902x *sii902x = connector_to_sii902x(connector);
+	const struct drm_display_mode *mod = mode;
 
-	return MODE_OK;
+	return sii902x_validate(sii902x, mod);
 }
 
 static const struct drm_connector_helper_funcs sii902x_connector_helper_funcs = {
@@ -499,11 +521,22 @@ static int sii902x_bridge_atomic_check(struct drm_bridge *bridge,
 	 * There might be flags negotiation supported in future but
 	 * set the bus flags in atomic_check statically for now.
 	 */
+
 	bridge_state->input_bus_cfg.flags = bridge->timings->input_bus_flags;
 
 	return 0;
 }
 
+static enum drm_mode_status
+sii902x_bridge_mode_valid(struct drm_bridge *bridge,
+			  const struct drm_display_info *info,
+			  const struct drm_display_mode *mode)
+{
+	struct sii902x *sii902x = bridge_to_sii902x(bridge);
+
+	return sii902x_validate(sii902x, mode);
+}
+
 static const struct drm_bridge_funcs sii902x_bridge_funcs = {
 	.attach = sii902x_bridge_attach,
 	.mode_set = sii902x_bridge_mode_set,
@@ -516,6 +549,7 @@ static const struct drm_bridge_funcs sii902x_bridge_funcs = {
 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 	.atomic_get_input_bus_fmts = sii902x_bridge_atomic_get_input_bus_fmts,
 	.atomic_check = sii902x_bridge_atomic_check,
+	.mode_valid = sii902x_bridge_mode_valid,
 };
 
 static int sii902x_mute(struct sii902x *sii902x, bool mute)
-- 
2.25.1

[PATCH v2 2/2] drm/bridge: Add pixel clock check in atomic_check

[Jayesh Choudhary]

Check the pixel clock for the mode in atomic_check and ensure that
it is within the range supported by the bridge.

Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
---
 drivers/gpu/drm/bridge/sii902x.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index ef7c3ab3386c..a5b7ee1e3bbe 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -517,11 +517,16 @@ static int sii902x_bridge_atomic_check(struct drm_bridge *bridge,
 				       struct drm_crtc_state *crtc_state,
 				       struct drm_connector_state *conn_state)
 {
+	if (crtc_state->mode.clock < SII902X_MIN_PIXEL_CLOCK_KHZ)
+		return MODE_CLOCK_LOW;
+
+	if (crtc_state->mode.clock > SII902X_MAX_PIXEL_CLOCK_KHZ)
+		return MODE_CLOCK_HIGH;
+
 	/*
 	 * There might be flags negotiation supported in future but
 	 * set the bus flags in atomic_check statically for now.
 	 */
-
 	bridge_state->input_bus_cfg.flags = bridge->timings->input_bus_flags;
 
 	return 0;
-- 
2.25.1

Re: [PATCH v2 1/2] drm/bridge: sii902x: Fix mode_valid hook

[Sam Ravnborg]

Hi Jayesh,

On Fri, May 24, 2024 at 01:03:04PM +0530, Jayesh Choudhary wrote:
> Currently, mode_valid hook returns all mode as valid and it is
> defined only in drm_connector_helper_funcs. With the introduction of
> 'DRM_BRIDGE_ATTACH_NO_CONNECTOR', connector is not initialized in
> bridge_attach call for cases when the encoder has this flag enabled.
> So add the mode_valid hook in drm_bridge_funcs as well with proper
> clock checks for maximum and minimum pixel clock supported by the
> bridge.
> 
> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
> ---
>  drivers/gpu/drm/bridge/sii902x.c | 38 ++++++++++++++++++++++++++++++--
>  1 file changed, 36 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
> index 2fbeda9025bf..ef7c3ab3386c 100644
> --- a/drivers/gpu/drm/bridge/sii902x.c
> +++ b/drivers/gpu/drm/bridge/sii902x.c
> @@ -163,6 +163,14 @@
>  
>  #define SII902X_AUDIO_PORT_INDEX		3
>  
> +/*
> + * The maximum resolution supported by the HDMI bridge is 1080p@60Hz
> + * and 1920x1200 requiring a pixel clock of 165MHz and the minimum
> + * resolution supported is 480p@60Hz requiring a pixel clock of 25MHz
> + */
> +#define SII902X_MIN_PIXEL_CLOCK_KHZ		25000
> +#define SII902X_MAX_PIXEL_CLOCK_KHZ		165000
> +
>  struct sii902x {
>  	struct i2c_client *i2c;
>  	struct regmap *regmap;
> @@ -310,12 +318,26 @@ static int sii902x_get_modes(struct drm_connector *connector)
>  	return num;
>  }
>  
> +static enum
> +drm_mode_status sii902x_validate(struct sii902x *sii902x,
> +				 const struct drm_display_mode *mode)
> +{
> +	if (mode->clock < SII902X_MIN_PIXEL_CLOCK_KHZ)
> +		return MODE_CLOCK_LOW;
> +
> +	if (mode->clock > SII902X_MAX_PIXEL_CLOCK_KHZ)
> +		return MODE_CLOCK_HIGH;
> +
> +	return MODE_OK;
> +}
> +
>  static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
>  					       struct drm_display_mode *mode)
>  {
> -	/* TODO: check mode */
> +	struct sii902x *sii902x = connector_to_sii902x(connector);
> +	const struct drm_display_mode *mod = mode;
>  
> -	return MODE_OK;
> +	return sii902x_validate(sii902x, mod);
>  }
>  
>  static const struct drm_connector_helper_funcs sii902x_connector_helper_funcs = {
> @@ -499,11 +521,22 @@ static int sii902x_bridge_atomic_check(struct drm_bridge *bridge,
>  	 * There might be flags negotiation supported in future but
>  	 * set the bus flags in atomic_check statically for now.
>  	 */
> +
>  	bridge_state->input_bus_cfg.flags = bridge->timings->input_bus_flags;

If you spin a v2 then drop the above change as you delete the line again
in the next patch.

	Sam

Re: [PATCH v2 1/2] drm/bridge: sii902x: Fix mode_valid hook

[Jayesh Choudhary]

Hello Sam,

On 24/05/24 13:48, Sam Ravnborg wrote:
> Hi Jayesh,
> 
> On Fri, May 24, 2024 at 01:03:04PM +0530, Jayesh Choudhary wrote:
>> Currently, mode_valid hook returns all mode as valid and it is
>> defined only in drm_connector_helper_funcs. With the introduction of
>> 'DRM_BRIDGE_ATTACH_NO_CONNECTOR', connector is not initialized in
>> bridge_attach call for cases when the encoder has this flag enabled.
>> So add the mode_valid hook in drm_bridge_funcs as well with proper
>> clock checks for maximum and minimum pixel clock supported by the
>> bridge.
>>
>> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
>> ---
>>   drivers/gpu/drm/bridge/sii902x.c | 38 ++++++++++++++++++++++++++++++--
>>   1 file changed, 36 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
>> index 2fbeda9025bf..ef7c3ab3386c 100644
>> --- a/drivers/gpu/drm/bridge/sii902x.c
>> +++ b/drivers/gpu/drm/bridge/sii902x.c
>> @@ -163,6 +163,14 @@
>>   
>>   #define SII902X_AUDIO_PORT_INDEX		3
>>   
>> +/*
>> + * The maximum resolution supported by the HDMI bridge is 1080p@60Hz
>> + * and 1920x1200 requiring a pixel clock of 165MHz and the minimum
>> + * resolution supported is 480p@60Hz requiring a pixel clock of 25MHz
>> + */
>> +#define SII902X_MIN_PIXEL_CLOCK_KHZ		25000
>> +#define SII902X_MAX_PIXEL_CLOCK_KHZ		165000
>> +
>>   struct sii902x {
>>   	struct i2c_client *i2c;
>>   	struct regmap *regmap;
>> @@ -310,12 +318,26 @@ static int sii902x_get_modes(struct drm_connector *connector)
>>   	return num;
>>   }
>>   
>> +static enum
>> +drm_mode_status sii902x_validate(struct sii902x *sii902x,
>> +				 const struct drm_display_mode *mode)
>> +{
>> +	if (mode->clock < SII902X_MIN_PIXEL_CLOCK_KHZ)
>> +		return MODE_CLOCK_LOW;
>> +
>> +	if (mode->clock > SII902X_MAX_PIXEL_CLOCK_KHZ)
>> +		return MODE_CLOCK_HIGH;
>> +
>> +	return MODE_OK;
>> +}
>> +
>>   static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
>>   					       struct drm_display_mode *mode)
>>   {
>> -	/* TODO: check mode */
>> +	struct sii902x *sii902x = connector_to_sii902x(connector);
>> +	const struct drm_display_mode *mod = mode;
>>   
>> -	return MODE_OK;
>> +	return sii902x_validate(sii902x, mod);
>>   }
>>   
>>   static const struct drm_connector_helper_funcs sii902x_connector_helper_funcs = {
>> @@ -499,11 +521,22 @@ static int sii902x_bridge_atomic_check(struct drm_bridge *bridge,
>>   	 * There might be flags negotiation supported in future but
>>   	 * set the bus flags in atomic_check statically for now.
>>   	 */
>> +
>>   	bridge_state->input_bus_cfg.flags = bridge->timings->input_bus_flags;
> 
> If you spin a v2 then drop the above change as you delete the line again
> in the next patch.
> 
> 	Sam

While splitting the patches, I must have messed up.
I will quickly send v3 with this fixed.

Thanks,
Jayesh

Re: [PATCH v2 1/2] drm/bridge: sii902x: Fix mode_valid hook

[Dmitry Baryshkov]

On Fri, May 24, 2024 at 01:03:04PM +0530, Jayesh Choudhary wrote:
> Currently, mode_valid hook returns all mode as valid and it is
> defined only in drm_connector_helper_funcs. With the introduction of
> 'DRM_BRIDGE_ATTACH_NO_CONNECTOR', connector is not initialized in
> bridge_attach call for cases when the encoder has this flag enabled.
> So add the mode_valid hook in drm_bridge_funcs as well with proper
> clock checks for maximum and minimum pixel clock supported by the
> bridge.
> 
> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
> ---
>  drivers/gpu/drm/bridge/sii902x.c | 38 ++++++++++++++++++++++++++++++--
>  1 file changed, 36 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
> index 2fbeda9025bf..ef7c3ab3386c 100644
> --- a/drivers/gpu/drm/bridge/sii902x.c
> +++ b/drivers/gpu/drm/bridge/sii902x.c
> @@ -163,6 +163,14 @@
>  
>  #define SII902X_AUDIO_PORT_INDEX		3
>  
> +/*
> + * The maximum resolution supported by the HDMI bridge is 1080p@60Hz
> + * and 1920x1200 requiring a pixel clock of 165MHz and the minimum
> + * resolution supported is 480p@60Hz requiring a pixel clock of 25MHz
> + */
> +#define SII902X_MIN_PIXEL_CLOCK_KHZ		25000
> +#define SII902X_MAX_PIXEL_CLOCK_KHZ		165000
> +
>  struct sii902x {
>  	struct i2c_client *i2c;
>  	struct regmap *regmap;
> @@ -310,12 +318,26 @@ static int sii902x_get_modes(struct drm_connector *connector)
>  	return num;
>  }
>  
> +static enum
> +drm_mode_status sii902x_validate(struct sii902x *sii902x,
> +				 const struct drm_display_mode *mode)
> +{
> +	if (mode->clock < SII902X_MIN_PIXEL_CLOCK_KHZ)
> +		return MODE_CLOCK_LOW;
> +
> +	if (mode->clock > SII902X_MAX_PIXEL_CLOCK_KHZ)
> +		return MODE_CLOCK_HIGH;
> +
> +	return MODE_OK;
> +}
> +
>  static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
>  					       struct drm_display_mode *mode)
>  {
> -	/* TODO: check mode */
> +	struct sii902x *sii902x = connector_to_sii902x(connector);
> +	const struct drm_display_mode *mod = mode;
>  
> -	return MODE_OK;
> +	return sii902x_validate(sii902x, mod);

If you have a mode_valid for the bridge, I don't think you need to
perform the same check for the connector.

>  }
>  
>  static const struct drm_connector_helper_funcs sii902x_connector_helper_funcs = {
> @@ -499,11 +521,22 @@ static int sii902x_bridge_atomic_check(struct drm_bridge *bridge,
>  	 * There might be flags negotiation supported in future but
>  	 * set the bus flags in atomic_check statically for now.
>  	 */
> +
>  	bridge_state->input_bus_cfg.flags = bridge->timings->input_bus_flags;
>  
>  	return 0;
>  }
>  
> +static enum drm_mode_status
> +sii902x_bridge_mode_valid(struct drm_bridge *bridge,
> +			  const struct drm_display_info *info,
> +			  const struct drm_display_mode *mode)
> +{
> +	struct sii902x *sii902x = bridge_to_sii902x(bridge);
> +
> +	return sii902x_validate(sii902x, mode);
> +}
> +
>  static const struct drm_bridge_funcs sii902x_bridge_funcs = {
>  	.attach = sii902x_bridge_attach,
>  	.mode_set = sii902x_bridge_mode_set,
> @@ -516,6 +549,7 @@ static const struct drm_bridge_funcs sii902x_bridge_funcs = {
>  	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
>  	.atomic_get_input_bus_fmts = sii902x_bridge_atomic_get_input_bus_fmts,
>  	.atomic_check = sii902x_bridge_atomic_check,
> +	.mode_valid = sii902x_bridge_mode_valid,
>  };
>  
>  static int sii902x_mute(struct sii902x *sii902x, bool mute)
> -- 
> 2.25.1
> 

-- 
With best wishes
Dmitry