diff options
| author | Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> | 2026-04-23 17:21:14 +0300 |
|---|---|---|
| committer | Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> | 2026-05-05 14:04:29 +0300 |
| commit | c0f8aaa7dcecee19a773a5454665998cdc848fda (patch) | |
| tree | a8203d3d70655bab69a7d3583af9b974c5a9b611 | |
| parent | b718f041842071b8c09faf658e3adca7b506e1bb (diff) | |
| download | lwn-c0f8aaa7dcecee19a773a5454665998cdc848fda.tar.gz lwn-c0f8aaa7dcecee19a773a5454665998cdc848fda.zip | |
drm/fourcc: Add DRM_FORMAT_Y8
Add greyscale Y8 format.
The 8-bit greyscale format has been discussed before, and the earlier
guidance was to use DRM_FORMAT_R8, as a single-channel 8-bit pixel.
However, adding DRM_FORMAT_Y8 makes sense, we can mark it as 'is_yuv' in
the drm_format_info, and this can help the drivers handle e.g.
full/limited range. This will distinguish two single-channel formats:
R8, which is a RGB format with the same value for all components, and
Y8, which is a Y-only YCbCr format, with Cb and Cr being neutral.
Acked-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Vishal Sagar <vishal.sagar@amd.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Simon Ser <contact@emersion.fr>
Link: https://patch.msgid.link/20260423-xilinx-formats-v10-3-c690c2b8ea89@ideasonboard.com
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
| -rw-r--r-- | drivers/gpu/drm/drm_fourcc.c | 1 | ||||
| -rw-r--r-- | include/uapi/drm/drm_fourcc.h | 9 |
2 files changed, 10 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c index 5b6d8f4686c4..c30266b8d051 100644 --- a/drivers/gpu/drm/drm_fourcc.c +++ b/drivers/gpu/drm/drm_fourcc.c @@ -275,6 +275,7 @@ const struct drm_format_info *__drm_format_info(u32 format) { .format = DRM_FORMAT_YVU422, .depth = 0, .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1, .is_yuv = true }, { .format = DRM_FORMAT_YUV444, .depth = 0, .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1, .is_yuv = true }, { .format = DRM_FORMAT_YVU444, .depth = 0, .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1, .is_yuv = true }, + { .format = DRM_FORMAT_Y8, .depth = 8, .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1, .is_yuv = true }, { .format = DRM_FORMAT_NV12, .depth = 0, .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2, .is_yuv = true }, { .format = DRM_FORMAT_NV21, .depth = 0, .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2, .is_yuv = true }, { .format = DRM_FORMAT_NV16, .depth = 0, .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true }, diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h index 7eb55028f35c..ede96c192169 100644 --- a/include/uapi/drm/drm_fourcc.h +++ b/include/uapi/drm/drm_fourcc.h @@ -441,6 +441,15 @@ extern "C" { #define DRM_FORMAT_YUV444 fourcc_code('Y', 'U', '2', '4') /* non-subsampled Cb (1) and Cr (2) planes */ #define DRM_FORMAT_YVU444 fourcc_code('Y', 'V', '2', '4') /* non-subsampled Cr (1) and Cb (2) planes */ +/* + * Y-only (greyscale) formats + * + * The Y-only formats are handled similarly to the YCbCr formats in the display + * pipeline, with the Cb and Cr implicitly neutral (0.0 in nominal values). This + * also means that COLOR_RANGE property applies to the Y-only formats. + */ + +#define DRM_FORMAT_Y8 fourcc_code('G', 'R', 'E', 'Y') /* 8-bit Y-only */ /* * Format Modifiers: |