Ensure HDMI connector initialization fails when the presence of
HDMI_COLORSPACE_YUV420 in the given supported_formats bitmask doesn't
match the value of drm_connector->ycbcr_420_allowed.

Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
---
 drivers/gpu/drm/drm_connector.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index fc35f47e2849ed6786d6223ac9c69e1c359fc648..ca7f43c8d6f1b31ef9d3a1ee05f4df930ecffac4 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -507,6 +507,9 @@ int drmm_connector_hdmi_init(struct drm_device *dev,
 	if (!supported_formats || !(supported_formats & BIT(HDMI_COLORSPACE_RGB)))
 		return -EINVAL;
 
+	if (connector->ycbcr_420_allowed != !!(supported_formats & BIT(HDMI_COLORSPACE_YUV420)))
+		return -EINVAL;
+
 	if (!(max_bpc == 8 || max_bpc == 10 || max_bpc == 12))
 		return -EINVAL;
 

-- 
2.47.0

On Tue, Dec 17, 2024 at 12:54:08AM +0200, Cristian Ciocaltea wrote:
> Ensure HDMI connector initialization fails when the presence of
> HDMI_COLORSPACE_YUV420 in the given supported_formats bitmask doesn't
> match the value of drm_connector->ycbcr_420_allowed.
> 
> Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
> ---
>  drivers/gpu/drm/drm_connector.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index fc35f47e2849ed6786d6223ac9c69e1c359fc648..ca7f43c8d6f1b31ef9d3a1ee05f4df930ecffac4 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -507,6 +507,9 @@ int drmm_connector_hdmi_init(struct drm_device *dev,
>  	if (!supported_formats || !(supported_formats & BIT(HDMI_COLORSPACE_RGB)))
>  		return -EINVAL;
>  
> +	if (connector->ycbcr_420_allowed != !!(supported_formats & BIT(HDMI_COLORSPACE_YUV420)))
> +		return -EINVAL;
> +
>  	if (!(max_bpc == 8 || max_bpc == 10 || max_bpc == 12))
>  		return -EINVAL;

The patch looks fine to me, but we need to have unit tests to cover this case.

Maxime

On 12/17/24 5:25 PM, Maxime Ripard wrote:
> On Tue, Dec 17, 2024 at 12:54:08AM +0200, Cristian Ciocaltea wrote:
>> Ensure HDMI connector initialization fails when the presence of
>> HDMI_COLORSPACE_YUV420 in the given supported_formats bitmask doesn't
>> match the value of drm_connector->ycbcr_420_allowed.
>>
>> Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
>> ---
>>  drivers/gpu/drm/drm_connector.c | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
>> index fc35f47e2849ed6786d6223ac9c69e1c359fc648..ca7f43c8d6f1b31ef9d3a1ee05f4df930ecffac4 100644
>> --- a/drivers/gpu/drm/drm_connector.c
>> +++ b/drivers/gpu/drm/drm_connector.c
>> @@ -507,6 +507,9 @@ int drmm_connector_hdmi_init(struct drm_device *dev,
>>  	if (!supported_formats || !(supported_formats & BIT(HDMI_COLORSPACE_RGB)))
>>  		return -EINVAL;
>>  
>> +	if (connector->ycbcr_420_allowed != !!(supported_formats & BIT(HDMI_COLORSPACE_YUV420)))
>> +		return -EINVAL;
>> +
>>  	if (!(max_bpc == 8 || max_bpc == 10 || max_bpc == 12))
>>  		return -EINVAL;
> 
> The patch looks fine to me, but we need to have unit tests to cover this case.

Unit tests added in v4:

https://lore.kernel.org/lkml/20241224-bridge-conn-fmt-prio-v4-4-a9ceb5671379@collabora.com/

Thanks,
Cristian

On Tue, Dec 17, 2024 at 12:54:08AM +0200, Cristian Ciocaltea wrote:
> Ensure HDMI connector initialization fails when the presence of
> HDMI_COLORSPACE_YUV420 in the given supported_formats bitmask doesn't
> match the value of drm_connector->ycbcr_420_allowed.
> 
> Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
> ---
>  drivers/gpu/drm/drm_connector.c | 3 +++
>  1 file changed, 3 insertions(+)
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

-- 
With best wishes
Dmitry