drm/fourcc: fix Amlogic format modifier masks

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

Simon Ser committed 5 years ago

Commit cc3283f1 parent dc25e371 file · +2 −2Browse files

Unified · Split

include/uapi/drm/drm_fourcc.h+2−2

@@ -1036,9 +1036,9 @@ drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier) · 1035 unmodified lines
1036	1036	* Not all combinations are valid, and different SoCs may support different
1037	1037	* combinations of layout and options.
1038	1038	*/
1039		−#define __fourcc_mod_amlogic_layout_mask 0xf
	1039	+#define __fourcc_mod_amlogic_layout_mask 0xff
1040	1040	#define __fourcc_mod_amlogic_options_shift 8
1041		−#define __fourcc_mod_amlogic_options_mask 0xf
	1041	+#define __fourcc_mod_amlogic_options_mask 0xff
1042	1042
1043	1043	#define DRM_FORMAT_MOD_AMLOGIC_FBC(__layout, __options) \
1044	1044	fourcc_mod_code(AMLOGIC, \