drm/edid: Introduce drm_hdmi_avi_infoframe_quant_range()
Pull the logic to populate the quantization range information
in the AVI infoframe into a small helper. We'll be adding a bit
more logic to it, and having it in a central place seems like a
good idea since it's based on the CEA-861 spec.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170111125725.8086-4-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 9d0a506..bca73a8 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -4292,6 +4292,32 @@ 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
+ * @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,
+ 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."
+ */
+ if (rgb_quant_range_selectable)
+ frame->quantization_range = rgb_quant_range;
+ else
+ frame->quantization_range = HDMI_QUANTIZATION_RANGE_DEFAULT;
+}
+EXPORT_SYMBOL(drm_hdmi_avi_infoframe_quant_range);
+
static enum hdmi_3d_structure
s3d_structure_from_display_mode(const struct drm_display_mode *mode)
{