Add a helper to retrieve the actual number of bits per pixel for a plane, taking into account the number of characters and pixels per block for tiled formats.
Signed-off-by: Geert Uytterhoeven geert@linux-m68k.org --- drivers/gpu/drm/drm_fourcc.c | 19 +++++++++++++++++++ include/drm/drm_fourcc.h | 1 + 2 files changed, 20 insertions(+)
diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c index 60ce63d728b8e308..5c77ce10f53e3a64 100644 --- a/drivers/gpu/drm/drm_fourcc.c +++ b/drivers/gpu/drm/drm_fourcc.c @@ -388,6 +388,25 @@ unsigned int drm_format_info_block_height(const struct drm_format_info *info, } EXPORT_SYMBOL(drm_format_info_block_height);
+/** + * drm_format_info_bpp - number of bits per pixel + * @info: pixel format info + * @plane: plane index + * + * Returns: + * The actual number of bits per pixel, depending on the plane index. + */ +unsigned int drm_format_info_bpp(const struct drm_format_info *info, int plane) +{ + if (!info || plane < 0 || plane >= info->num_planes) + return 0; + + return info->char_per_block[plane] * 8 / + (drm_format_info_block_width(info, plane) * + drm_format_info_block_height(info, plane)); +} +EXPORT_SYMBOL(drm_format_info_bpp); + /** * drm_format_info_min_pitch - computes the minimum required pitch in bytes * @info: pixel format info diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h index 22aa64d07c7905e2..3800a7ad7f0cda7a 100644 --- a/include/drm/drm_fourcc.h +++ b/include/drm/drm_fourcc.h @@ -313,6 +313,7 @@ unsigned int drm_format_info_block_width(const struct drm_format_info *info, int plane); unsigned int drm_format_info_block_height(const struct drm_format_info *info, int plane); +unsigned int drm_format_info_bpp(const struct drm_format_info *info, int plane); uint64_t drm_format_info_min_pitch(const struct drm_format_info *info, int plane, unsigned int buffer_width);