diff options
Diffstat (limited to 'drivers/gpu/drm/drm_edid.c')
| -rw-r--r-- | drivers/gpu/drm/drm_edid.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 4ff04aa84dd0..baa6ccb3e18b 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -3768,6 +3768,25 @@ bool drm_rgb_quant_range_selectable(struct edid *edid) } EXPORT_SYMBOL(drm_rgb_quant_range_selectable); +/** + * drm_default_rgb_quant_range - default RGB quantization range + * @mode: display mode + * + * Determine the default RGB quantization range for the mode, + * as specified in CEA-861. + * + * Return: The default RGB quantization range for the mode + */ +enum hdmi_quantization_range +drm_default_rgb_quant_range(const struct drm_display_mode *mode) +{ + /* All CEA modes other than VIC 1 use limited quantization range. */ + return drm_match_cea_mode(mode) > 1 ? + HDMI_QUANTIZATION_RANGE_LIMITED : + HDMI_QUANTIZATION_RANGE_FULL; +} +EXPORT_SYMBOL(drm_default_rgb_quant_range); + static void drm_parse_hdmi_deep_color_info(struct drm_connector *connector, const u8 *hdmi) { @@ -4273,6 +4292,52 @@ drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame, } EXPORT_SYMBOL(drm_hdmi_avi_infoframe_from_display_mode); +/** + * drm_hdmi_avi_infoframe_quant_range() - fill the HDMI AVI infoframe + * quantization range information + * @frame: HDMI AVI infoframe + * @mode: DRM display mode + * @rgb_quant_range: RGB quantization range (Q) + * @rgb_quant_range_selectable: Sink support selectable RGB quantization range (QS) + */ +void +drm_hdmi_avi_infoframe_quant_range(struct hdmi_avi_infoframe *frame, + const struct drm_display_mode *mode, + enum hdmi_quantization_range rgb_quant_range, + bool rgb_quant_range_selectable) +{ + /* + * CEA-861: + * "A Source shall not send a non-zero Q value that does not correspond + * to the default RGB Quantization Range for the transmitted Picture + * unless the Sink indicates support for the Q bit in a Video + * Capabilities Data Block." + * + * HDMI 2.0 recommends sending non-zero Q when it does match the + * default RGB quantization range for the mode, even when QS=0. + */ + if (rgb_quant_range_selectable || + rgb_quant_range == drm_default_rgb_quant_range(mode)) + frame->quantization_range = rgb_quant_range; + else + frame->quantization_range = HDMI_QUANTIZATION_RANGE_DEFAULT; + + /* + * CEA-861-F: + * "When transmitting any RGB colorimetry, the Source should set the + * YQ-field to match the RGB Quantization Range being transmitted + * (e.g., when Limited Range RGB, set YQ=0 or when Full Range RGB, + * set YQ=1) and the Sink shall ignore the YQ-field." + */ + if (rgb_quant_range == HDMI_QUANTIZATION_RANGE_LIMITED) + frame->ycc_quantization_range = + HDMI_YCC_QUANTIZATION_RANGE_LIMITED; + else + frame->ycc_quantization_range = + HDMI_YCC_QUANTIZATION_RANGE_FULL; +} +EXPORT_SYMBOL(drm_hdmi_avi_infoframe_quant_range); + static enum hdmi_3d_structure s3d_structure_from_display_mode(const struct drm_display_mode *mode) { |