drm: Add HDMI infoframe helpers
Add a generic helper to fill in an HDMI AVI infoframe with data
extracted from a DRM display mode.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index f8dae851..1e82882 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -7,6 +7,7 @@
menuconfig DRM
tristate "Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)"
depends on (AGP || AGP=n) && !EMULATED_CMPXCHG && MMU
+ select HDMI
select I2C
select I2C_ALGOBIT
select DMA_SHARED_BUFFER
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 6995d2f..c194f4e 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -29,6 +29,7 @@
*/
#include <linux/kernel.h>
#include <linux/slab.h>
+#include <linux/hdmi.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <drm/drmP.h>
@@ -2856,3 +2857,35 @@
return num_modes;
}
EXPORT_SYMBOL(drm_add_modes_noedid);
+
+/**
+ * drm_hdmi_avi_infoframe_from_display_mode() - fill an HDMI AVI infoframe with
+ * data from a DRM display mode
+ * @frame: HDMI AVI infoframe
+ * @mode: DRM display mode
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int
+drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
+ const struct drm_display_mode *mode)
+{
+ int err;
+
+ if (!frame || !mode)
+ return -EINVAL;
+
+ err = hdmi_avi_infoframe_init(frame);
+ if (err < 0)
+ return err;
+
+ frame->video_code = drm_match_cea_mode(mode);
+ if (!frame->video_code)
+ return 0;
+
+ frame->picture_aspect = HDMI_PICTURE_ASPECT_NONE;
+ frame->active_aspect = HDMI_ACTIVE_ASPECT_PICTURE;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_hdmi_avi_infoframe_from_display_mode);