From: Ankit Nautiyal ankit.k.nautiyal@intel.com
To enable aspect-ratio support in DRM, blindly exposing the aspect ratio information along with mode, can break things in existing non-atomic user-spaces which have no intention or support to use this aspect ratio information.
To avoid this, a new drm client cap is required to enable a non-atomic user-space to advertise if it supports modes with aspect-ratio. Based on this cap value, the kernel will take a call on exposing the aspect ratio info in modes or not.
This patch adds the client cap for aspect-ratio.
Since no atomic-userspaces blow up on receiving aspect-ratio information, the client cap for aspect-ratio is always enabled for atomic clients.
Cc: Ville Syrjala ville.syrjala@linux.intel.com Cc: Shashank Sharma shashank.sharma@intel.com Signed-off-by: Ankit Nautiyal ankit.k.nautiyal@intel.com
V3: rebase V4: As suggested by Marteen Lankhorst modified the commit message explaining the need to use the DRM cap for aspect-ratio. Also, tweaked the comment lines in the code for better understanding and clarity, as recommended by Shashank Sharma. V5: rebase V6: rebase V7: rebase V8: rebase V9: rebase V10: rebase V11: rebase V12: As suggested by Daniel Vetter and Ville Syrjala, always enable aspect-ratio client cap for atomic userspaces, if no atomic userspace breaks on aspect-ratio bits. V13: rebase
Reviewed-by: Shashank Sharma shashank.sharma@intel.com --- drivers/gpu/drm/drm_ioctl.c | 9 +++++++++ include/drm/drm_file.h | 8 ++++++++ include/uapi/drm/drm.h | 7 +++++++ 3 files changed, 24 insertions(+)
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index af78291..0379983 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -324,6 +324,15 @@ drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) return -EINVAL; file_priv->atomic = req->value; file_priv->universal_planes = req->value; + /* + * No atomic user-space blows up on aspect ratio mode bits. + */ + file_priv->aspect_ratio_allowed = req->value; + break; + case DRM_CLIENT_CAP_ASPECT_RATIO: + if (req->value > 1) + return -EINVAL; + file_priv->aspect_ratio_allowed = req->value; break; default: return -EINVAL; diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h index 5176c37..02b7dde 100644 --- a/include/drm/drm_file.h +++ b/include/drm/drm_file.h @@ -182,6 +182,14 @@ struct drm_file { unsigned atomic:1;
/** + * @aspect_ratio_allowed: + * + * True, if client can handle picture aspect ratios, and has requested + * to pass this information along with the mode. + */ + unsigned aspect_ratio_allowed:1; + + /** * @is_master: * * This client is the creator of @master. Protected by struct diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 6fdff59..9c660e1 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -680,6 +680,13 @@ struct drm_get_cap { */ #define DRM_CLIENT_CAP_ATOMIC 3
+/** + * DRM_CLIENT_CAP_ASPECT_RATIO + * + * If set to 1, the DRM core will provide aspect ratio information in modes. + */ +#define DRM_CLIENT_CAP_ASPECT_RATIO 4 + /** DRM_IOCTL_SET_CLIENT_CAP ioctl argument type */ struct drm_set_client_cap { __u64 capability;