[PATCH v3 01/10] drm/fourcc: Add drm_format_info_bpp() helper
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: 2022-07-08 18:21:56
Also in:
dri-devel, linux-m68k, lkml
Subsystem:
drm drivers, drm drivers and misc gpu patches, the rest · Maintainers:
David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Linus Torvalds
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> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> --- v3: - Add Reviewed-by, v2: - Move up. --- 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 07741b678798b0f1..cf48ea0b2cb70ba8 100644
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c@@ -370,6 +370,25 @@ 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);
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2.25.1