drm/edid: Handle EDID 1.4 range descriptor h/vfreq offsets
EDID 1.4 introduced some extra flags in the range
descriptor to support min/max h/vfreq >= 255. Consult them
to correctly parse the vfreq limits.
Note that some combinations of the flags are documented
as "reserved" (as are some other values in the descriptor)
but explicitly checking for those doesn't seem particularly
worthwile since we end up with bogus results whether we
decode them or not.
v2: Increase the storage to u16 to make it work (Jani)
Note the "reserved" values situation (Jani)
v3: Document the EDID version number in the defines
Drop some bogus (u8) casts
Cc: stable@vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6519
References: https://gitlab.freedesktop.org/drm/intel/-/issues/6484
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220826213501.31490-2-ville.syrjala@linux.intel.com
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index a1705d6..7df7876 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -319,8 +319,8 @@ enum drm_panel_orientation {
* EDID's detailed monitor range
*/
struct drm_monitor_range_info {
- u8 min_vfreq;
- u8 max_vfreq;
+ u16 min_vfreq;
+ u16 max_vfreq;
};
/**
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
index 2181977..1ed61e2 100644
--- a/include/drm/drm_edid.h
+++ b/include/drm/drm_edid.h
@@ -92,6 +92,11 @@ struct detailed_data_string {
u8 str[13];
} __attribute__((packed));
+#define DRM_EDID_RANGE_OFFSET_MIN_VFREQ (1 << 0) /* 1.4 */
+#define DRM_EDID_RANGE_OFFSET_MAX_VFREQ (1 << 1) /* 1.4 */
+#define DRM_EDID_RANGE_OFFSET_MIN_HFREQ (1 << 2) /* 1.4 */
+#define DRM_EDID_RANGE_OFFSET_MAX_HFREQ (1 << 3) /* 1.4 */
+
#define DRM_EDID_DEFAULT_GTF_SUPPORT_FLAG 0x00
#define DRM_EDID_RANGE_LIMITS_ONLY_FLAG 0x01
#define DRM_EDID_SECONDARY_GTF_SUPPORT_FLAG 0x02
