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

[Jayesh Choudhary]

Hello Maxime,

Thanks for the review.

On 15/04/24 13:10, Maxime Ripard wrote:

Hi,

On Mon, Apr 08, 2024 at 01:44:35PM +0530, Jayesh Choudhary wrote:

Currently, mode_valid hook returns all mode as valid. Add the check
for the maximum and minimum pixel clock that the bridge can support
while validating a mode.

Signed-off-by: Jayesh Choudhary 
---
  drivers/gpu/drm/bridge/sii902x.c | 16 +++-
  1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 8f84e98249c7..658819199c84 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -163,6 +163,16 @@
  
  #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
+ *
+ * (drm_display_mode clock is in kHz)
+ */
+#define SII902X_MIN_PIXEL_CLOCK25000
+#define SII902X_MAX_PIXEL_CLOCK165000
+


You should probably add a KHZ suffix or something to make it obvious.
The natural unit for a frequency is Hertz.


Okay.
Instead of adding the kHz in comments, I will add that in suffix
like SII902X_MIN_PIXEL_CLOCK_KHZ.




  struct sii902x {
struct i2c_client *i2c;
struct regmap *regmap;
@@ -313,7 +323,11 @@ static int sii902x_get_modes(struct drm_connector 
*connector)
  static enum drm_mode_status sii902x_mode_valid(struct drm_connector 
*connector,
   struct drm_display_mode *mode)
  {
-   /* TODO: check mode */
+   if (mode->clock < SII902X_MIN_PIXEL_CLOCK)
+   return MODE_CLOCK_LOW;
+
+   if (mode->clock > SII902X_MAX_PIXEL_CLOCK)
+   return MODE_CLOCK_HIGH;
  
  	return MODE_OK;

  }


It's something you should do in atomic_check too



Like using clock from adjusted mode in crtc_state?
Will update in the next revision.

Warm Regards,
-Jayesh

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

[Maxime Ripard]

Hi,

On Mon, Apr 08, 2024 at 01:44:35PM +0530, Jayesh Choudhary wrote:
> Currently, mode_valid hook returns all mode as valid. Add the check
> for the maximum and minimum pixel clock that the bridge can support
> while validating a mode.
> 
> Signed-off-by: Jayesh Choudhary 
> ---
>  drivers/gpu/drm/bridge/sii902x.c | 16 +++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/bridge/sii902x.c 
> b/drivers/gpu/drm/bridge/sii902x.c
> index 8f84e98249c7..658819199c84 100644
> --- a/drivers/gpu/drm/bridge/sii902x.c
> +++ b/drivers/gpu/drm/bridge/sii902x.c
> @@ -163,6 +163,16 @@
>  
>  #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
> + *
> + * (drm_display_mode clock is in kHz)
> + */
> +#define SII902X_MIN_PIXEL_CLOCK  25000
> +#define SII902X_MAX_PIXEL_CLOCK  165000
> +

You should probably add a KHZ suffix or something to make it obvious.
The natural unit for a frequency is Hertz.

>  struct sii902x {
>   struct i2c_client *i2c;
>   struct regmap *regmap;
> @@ -313,7 +323,11 @@ static int sii902x_get_modes(struct drm_connector 
> *connector)
>  static enum drm_mode_status sii902x_mode_valid(struct drm_connector 
> *connector,
>  struct drm_display_mode *mode)
>  {
> - /* TODO: check mode */
> + if (mode->clock < SII902X_MIN_PIXEL_CLOCK)
> + return MODE_CLOCK_LOW;
> +
> + if (mode->clock > SII902X_MAX_PIXEL_CLOCK)
> + return MODE_CLOCK_HIGH;
>  
>   return MODE_OK;
>  }

It's something you should do in atomic_check too

Maxime


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[PATCH] drm/bridge: sii902x: Fix mode_valid hook

[Jayesh Choudhary]

Currently, mode_valid hook returns all mode as valid. Add the check
for the maximum and minimum pixel clock that the bridge can support
while validating a mode.

Signed-off-by: Jayesh Choudhary 
---
 drivers/gpu/drm/bridge/sii902x.c | 16 +++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 8f84e98249c7..658819199c84 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -163,6 +163,16 @@
 
 #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
+ *
+ * (drm_display_mode clock is in kHz)
+ */
+#define SII902X_MIN_PIXEL_CLOCK25000
+#define SII902X_MAX_PIXEL_CLOCK165000
+
 struct sii902x {
struct i2c_client *i2c;
struct regmap *regmap;
@@ -313,7 +323,11 @@ static int sii902x_get_modes(struct drm_connector 
*connector)
 static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
   struct drm_display_mode *mode)
 {
-   /* TODO: check mode */
+   if (mode->clock < SII902X_MIN_PIXEL_CLOCK)
+   return MODE_CLOCK_LOW;
+
+   if (mode->clock > SII902X_MAX_PIXEL_CLOCK)
+   return MODE_CLOCK_HIGH;
 
return MODE_OK;
 }
-- 
2.25.1