From: Ville Syrjälä ville.syrjala@linux.intel.com
drm_rgb_quant_range_selectable() will report whether the monitor claims to support for RGB quantization range selection.
The information can be found in the CEA Video capability block.
Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com --- drivers/gpu/drm/drm_edid.c | 33 +++++++++++++++++++++++++++++++++ include/drm/drm_crtc.h | 1 + 2 files changed, 34 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 5a3770f..deba722 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1483,9 +1483,11 @@ add_detailed_modes(struct drm_connector *connector, struct edid *edid, #define VIDEO_BLOCK 0x02 #define VENDOR_BLOCK 0x03 #define SPEAKER_BLOCK 0x04 +#define VIDEO_CAPABILITY_BLOCK 0x07 #define EDID_BASIC_AUDIO (1 << 6) #define EDID_CEA_YCRCB444 (1 << 5) #define EDID_CEA_YCRCB422 (1 << 4) +#define EDID_CEA_VCDB_QS (1 << 6)
/** * Search EDID for CEA extension block. @@ -1902,6 +1904,37 @@ end: EXPORT_SYMBOL(drm_detect_monitor_audio);
/** + * drm_rgb_quant_range_selectable - is RGB quantization range selectable? + * + * Check whether the monitor reports the RGB quantization range selection + * as supported. The AVI infoframe can then be used to inform the monitor + * which quantzation range (full or limited) is used. + */ +bool drm_rgb_quant_range_selectable(struct edid *edid) +{ + u8 *edid_ext; + int i, start, end; + + edid_ext = drm_find_cea_extension(edid); + if (!edid_ext) + return false; + + if (cea_db_offsets(edid_ext, &start, &end)) + return false; + + for_each_cea_db(edid_ext, i, start, end) { + if (cea_db_tag(&edid_ext[i]) == VIDEO_CAPABILITY_BLOCK && + cea_db_payload_len(&edid_ext[i]) == 2) { + DRM_DEBUG_KMS("CEA VCDB 0x%02x\n", edid_ext[i + 2]); + return edid_ext[i + 2] & EDID_CEA_VCDB_QS; + } + } + + return false; +} +EXPORT_SYMBOL(drm_rgb_quant_range_selectable); + +/** * drm_add_display_info - pull display info out if present * @edid: EDID data * @info: display info (attached to connector) diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 00d78b5..30892dc 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -1033,6 +1033,7 @@ extern u8 *drm_find_cea_extension(struct edid *edid); extern u8 drm_match_cea_mode(struct drm_display_mode *to_match); extern bool drm_detect_hdmi_monitor(struct edid *edid); extern bool drm_detect_monitor_audio(struct edid *edid); +extern bool drm_rgb_quant_range_selectable(struct edid *edid); extern int drm_mode_page_flip_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); extern struct drm_display_mode *drm_cvt_mode(struct drm_device *dev,