diff options
| -rw-r--r-- | Documentation/gpu/drm-uapi.rst | 13 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_debugfs_crc.c | 8 | ||||
| -rw-r--r-- | include/uapi/drm/drm.h | 4 |
3 files changed, 19 insertions, 6 deletions
diff --git a/Documentation/gpu/drm-uapi.rst b/Documentation/gpu/drm-uapi.rst index 04bdc7a91d53..7e51dd40bf6e 100644 --- a/Documentation/gpu/drm-uapi.rst +++ b/Documentation/gpu/drm-uapi.rst @@ -457,6 +457,19 @@ Userspace API Structures .. kernel-doc:: include/uapi/drm/drm_mode.h :doc: overview +.. _crtc_index: + +CRTC index +---------- + +CRTC's have both an object ID and an index, and they are not the same thing. +The index is used in cases where a densely packed identifier for a CRTC is +needed, for instance a bitmask of CRTC's. The member possible_crtcs of struct +drm_mode_get_plane is an example. + +DRM_IOCTL_MODE_GETRESOURCES populates a structure with an array of CRTC ID's, +and the CRTC index is its position in this array. + .. kernel-doc:: include/uapi/drm/drm.h :internal: diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c index 3dd70d813f69..bbc3bc4ba844 100644 --- a/drivers/gpu/drm/drm_debugfs_crc.c +++ b/drivers/gpu/drm/drm_debugfs_crc.c @@ -46,10 +46,10 @@ * it reached a given hardware component (a CRC sampling "source"). * * Userspace can control generation of CRCs in a given CRTC by writing to the - * file dri/0/crtc-N/crc/control in debugfs, with N being the index of the CRTC. - * Accepted values are source names (which are driver-specific) and the "auto" - * keyword, which will let the driver select a default source of frame CRCs - * for this CRTC. + * file dri/0/crtc-N/crc/control in debugfs, with N being the :ref:`index of + * the CRTC<crtc_index>`. Accepted values are source names (which are + * driver-specific) and the "auto" keyword, which will let the driver select a + * default source of frame CRCs for this CRTC. * * Once frame CRC generation is enabled, userspace can capture them by reading * the dri/0/crtc-N/crc/data file. Each line in that file contains the frame diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index d043752a74cf..e1f49dd241f7 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -635,8 +635,8 @@ struct drm_gem_open { /** * DRM_CAP_VBLANK_HIGH_CRTC * - * If set to 1, the kernel supports specifying a CRTC index in the high bits of - * &drm_wait_vblank_request.type. + * If set to 1, the kernel supports specifying a :ref:`CRTC index<crtc_index>` + * in the high bits of &drm_wait_vblank_request.type. * * Starting kernel version 2.6.39, this capability is always set to 1. */ |