From: Simon Ser contact@emersion.fr
[ Upstream commit cc3283f8f41f741fbaef63d0503d8fb4a7919100 ]
The comment says the layout and options use 8 bits, and the shift uses 8 bits. However the mask is 0xf, ie. 0b00001111 (4 bits).
This could be surprising when introducing new layouts or options that take more than 4 bits, as this would silently drop the high bits.
Make the masks consistent with the comment and the shift.
Found when writing a drm_info patch [1].
[1]: https://github.com/ascent12/drm_info/pull/67
Signed-off-by: Simon Ser contact@emersion.fr Fixes: d6528ec88309 ("drm/fourcc: Add modifier definitions for describing Amlogic Video Framebuffer Compression") Cc: Neil Armstrong narmstrong@baylibre.com Cc: Sam Ravnborg sam@ravnborg.org Cc: Kevin Hilman khilman@baylibre.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Acked-by: Neil Armstrong narmstrong@baylibre.com Link: https://patchwork.freedesktop.org/patch/msgid/20210110125103.15447-1-contact... Signed-off-by: Sasha Levin sashal@kernel.org --- include/uapi/drm/drm_fourcc.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h index 723c8e23ca87d..5f42a14481bd4 100644 --- a/include/uapi/drm/drm_fourcc.h +++ b/include/uapi/drm/drm_fourcc.h @@ -1036,9 +1036,9 @@ drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier) * Not all combinations are valid, and different SoCs may support different * combinations of layout and options. */ -#define __fourcc_mod_amlogic_layout_mask 0xf +#define __fourcc_mod_amlogic_layout_mask 0xff #define __fourcc_mod_amlogic_options_shift 8 -#define __fourcc_mod_amlogic_options_mask 0xf +#define __fourcc_mod_amlogic_options_mask 0xff
#define DRM_FORMAT_MOD_AMLOGIC_FBC(__layout, __options) \ fourcc_mod_code(AMLOGIC, \