[PATCH v3 6/8] drm: Expose modes with aspect ratio, only if requested

[Ville Syrjälä]

On Fri, Jan 12, 2018 at 11:51:34AM +0530, Nautiyal, Ankit K wrote:
> From: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> 
> We parse the EDID and add all the modes in the connector's
> modelist. This adds CEA modes with aspect ratio information
> too, regadless of if user space requested this information or
> not.
> 
> This patch prunes the modes with aspect-ratio information, from
> a connector's modelist, if the user-space has not set the aspect
> ratio DRM client cap.
> 
> Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
> Cc: Shashank Sharma <shashank.sharma at intel.com>
> Cc: Jose Abreu <jose.abreu at synopsys.com>
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> 
> V3: As suggested by Ville, modified the mechanism of pruning of
> modes with aspect-ratio, if the aspect-ratio is not supported.
> Instead of straight away pruning such a mode, the mode is
> retained with aspect-ratio bits set to zero, provided it is
> unique.
> ---
>  drivers/gpu/drm/drm_connector.c | 31 +++++++++++++++++++++++++++----
>  1 file changed, 27 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index b85a774..d968ec3 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -1502,7 +1502,8 @@ static struct drm_encoder *drm_connector_get_encoder(struct drm_connector *conne
>  	return connector->encoder;
>  }
>  
> -static bool drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
> +static bool drm_mode_expose_to_userspace(const struct drm_display_mode *last_mode,
> +					 const struct drm_display_mode *mode,
>  					 const struct drm_file *file_priv)
>  {
>  	/*
> @@ -1511,6 +1512,18 @@ static bool drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
>  	 */
>  	if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
>  		return false;
> +	/*
> +	 * If user-space hasn't configured the driver to expose the modes
> +	 * with aspect-ratio, don't expose them.
> +	 */
> +	if (!file_priv->aspect_ratio_allowed &&
> +	    mode->picture_aspect_ratio != HDMI_PICTURE_ASPECT_NONE &&
> +	    drm_mode_match(mode, last_mode,
> +			   DRM_MODE_MATCH_TIMINGS |
> +			   DRM_MODE_MATCH_CLOCK |
> +			   DRM_MODE_MATCH_FLAGS |
> +			   DRM_MODE_MATCH_3D_FLAGS))
> +		return false;
>  
>  	return true;
>  }
> @@ -1522,6 +1535,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
>  	struct drm_connector *connector;
>  	struct drm_encoder *encoder;
>  	struct drm_display_mode *mode;
> +	struct drm_display_mode last_valid_mode;

A pointer should be sufficient.

>  	int mode_count = 0;
>  	int encoders_count = 0;
>  	int ret = 0;
> @@ -1577,9 +1591,12 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
>  	out_resp->connection = connector->status;
>  
>  	/* delayed so we get modes regardless of pre-fill_modes state */
> +	memset(&last_valid_mode, 0, sizeof(struct drm_display_mode));
>  	list_for_each_entry(mode, &connector->modes, head)
> -		if (drm_mode_expose_to_userspace(mode, file_priv))
> +		if (drm_mode_expose_to_userspace(&last_valid_mode, mode, file_priv)) {
>  			mode_count++;
> +			drm_mode_copy(&last_valid_mode, mode);
> +		}
>  
>  	/*
>  	 * This ioctl is called twice, once to determine how much space is
> @@ -1588,10 +1605,16 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
>  	if ((out_resp->count_modes >= mode_count) && mode_count) {
>  		copied = 0;
>  		mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
> +		memset(&last_valid_mode, 0, sizeof(struct drm_display_mode));
>  		list_for_each_entry(mode, &connector->modes, head) {
> -			if (!drm_mode_expose_to_userspace(mode, file_priv))
> +			if (!drm_mode_expose_to_userspace(&last_valid_mode,
> +							  mode,
> +							  file_priv))
>  				continue;
> -
> +			if (!file_priv->aspect_ratio_allowed)
> +				mode->picture_aspect_ratio =
> +						HDMI_PICTURE_ASPECT_NONE;

Here you're clobbering the internal mode structure. That's not
acceptable.

> +			drm_mode_copy(&last_valid_mode, mode);
>  			drm_mode_convert_to_umode(&u_mode, mode);
>  			if (copy_to_user(mode_ptr + copied,
>  					 &u_mode, sizeof(u_mode))) {
> -- 
> 2.7.4

-- 
Ville Syrjälä
Intel OTC