@@ -46,6 +46,18 @@ uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth)
case 8:
if (depth == 8)
fmt = DRM_FORMAT_C8;
+ fallthrough;
+ case 4:
+ if (depth == 4)
+ fmt = DRM_FORMAT_C4;
+ fallthrough;
+ case 2:
+ if (depth == 2)
+ fmt = DRM_FORMAT_C2;
+ fallthrough;
+ case 1:
+ if (depth == 1)
+ fmt = DRM_FORMAT_C1;
break;
case 16:
@@ -132,6 +144,12 @@ EXPORT_SYMBOL(drm_driver_legacy_fb_format);
const struct drm_format_info *__drm_format_info(u32 format)
{
static const struct drm_format_info formats[] = {
+ { .format = DRM_FORMAT_C1, .depth = 1, .num_planes = 1,
+ .char_per_block = { 1, }, .block_w = { 8, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 },
+ { .format = DRM_FORMAT_C2, .depth = 2, .num_planes = 1,
+ .char_per_block = { 1, }, .block_w = { 4, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 },
+ { .format = DRM_FORMAT_C4, .depth = 4, .num_planes = 1,
+ .char_per_block = { 1, }, .block_w = { 2, }, .block_h = { 1, }, .hsub = 1, .vsub = 1 },
{ .format = DRM_FORMAT_C8, .depth = 8, .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
{ .format = DRM_FORMAT_R8, .depth = 8, .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
{ .format = DRM_FORMAT_R10, .depth = 10, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
@@ -99,6 +99,9 @@ extern "C" {
#define DRM_FORMAT_INVALID 0
/* color index */
+#define DRM_FORMAT_C1 fourcc_code('C', '1', ' ', ' ') /* [0] C */
+#define DRM_FORMAT_C2 fourcc_code('C', '2', ' ', ' ') /* [1:0] C */
+#define DRM_FORMAT_C4 fourcc_code('C', '4', ' ', ' ') /* [3:0] C */
#define DRM_FORMAT_C8 fourcc_code('C', '8', ' ', ' ') /* [7:0] C */
/* 8 bpp Red */
Introduce fourcc codes for color-indexed frame buffer formats with two, four, and sixteen color, and provide a suitable mapping from bit per pixel and depth to fourcc codes. As the number of bits per pixel is less than eight, these rely on proper block handling for the calculation of bits per pixel and pitch. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> --- Do we want to keep the rounding down if depth < bpp, or insist on depth == bpp? I don't think the rounding down will still be needed after "[PATCH 4/8] drm/client: Use actual bpp when allocating frame buffers". --- drivers/gpu/drm/drm_fourcc.c | 18 ++++++++++++++++++ include/uapi/drm/drm_fourcc.h | 3 +++ 2 files changed, 21 insertions(+)