<html> <head> <meta content="text/html; charset=windows-1252" http-equiv="Content-Type"> </head> <body bgcolor="#FFFFFF" text="#000000"> <div class="moz-cite-prefix">On 4/20/2018 7:37 PM, Ville Syrjälä wrote: </div> <blockquote cite="mid:20180420140725.GB13908@intel.com" type="cite"> <pre wrap="">On Fri, Apr 20, 2018 at 07:01:46PM +0530, Nautiyal, Ankit K wrote: </pre> <blockquote type="cite"> <pre wrap="">From: Ankit Nautiyal <a class="moz-txt-link-rfc2396E" href="mailto:ankit.k.nautiyal@intel.com"><ankit.k.nautiyal@intel.com></a> To enable aspect-ratio support in DRM, blindly exposing the aspect ratio information along with mode, can break things in existing 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 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. Cc: Ville Syrjala <a class="moz-txt-link-rfc2396E" href="mailto:ville.syrjala@linux.intel.com"><ville.syrjala@linux.intel.com></a> Cc: Shashank Sharma <a class="moz-txt-link-rfc2396E" href="mailto:shashank.sharma@intel.com"><shashank.sharma@intel.com></a> Signed-off-by: Ankit Nautiyal <a class="moz-txt-link-rfc2396E" href="mailto:ankit.k.nautiyal@intel.com"><ankit.k.nautiyal@intel.com></a> 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: added comment explaining that no userspace breaks on aspect-ratio mode bits. Reviewed-by: Shashank Sharma <a class="moz-txt-link-rfc2396E" href="mailto:shashank.sharma@intel.com"><shashank.sharma@intel.com></a> --- 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..39c8eab 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -325,6 +325,15 @@ drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) file_priv->atomic = req->value; file_priv->universal_planes = req->value; break; + case DRM_CLIENT_CAP_ASPECT_RATIO: + if (req->value > 1) + return -EINVAL; + /* + * No Atomic userspace blows up on aspect ratio mode bits. Checked in + * wayland/weston, xserver, and hardware-composer modeset paths. + */ </pre> </blockquote> <pre wrap=""> Bogus indentation. </pre> </blockquote> Thanks to point that out, will fix this. <blockquote cite="mid:20180420140725.GB13908@intel.com" type="cite"> <pre wrap=""> Also where's the aspect_ratio_allowed handling for the atomic cap? Or did we decide against it after all?</pre> </blockquote> As discussed, aspect ratio is handled in the atomic modeset path, where in the modeset requests with aspect-ratios are rejected, if the aspect-ratio cap not set. The part which is dropped is - hiding the aspect-ratio information, while returning a mode blob in the drm_mode_get_blob if the cap is not set. The patch was dropped as no user-space currently uses getblob ioctl to get the mode-blob. Regards, Ankit <blockquote cite="mid:20180420140725.GB13908@intel.com" type="cite"> <pre wrap=""> </pre> <blockquote type="cite"> <pre wrap="">+ 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; -- 2.7.4 </pre> </blockquote> <pre wrap=""> </pre> </blockquote> </body> </html>