drm/radeon: rework audio option

In 3.12 I changed audio to be enabled by default,
but you still had to turn it on via xrandr.  This
was confusing to users so change it to minic the
previous behavior:

- audio option is set to -1 (auto) by default which is
  the current 3.12 behavior (audio is enabled but requires
  xrandr to turn it on).
- if audio = 1, the audio is enabled without needing
  to mess with xrandr (previous behavior)
- audio = 0 disables audio

It retains the new feature of allowing the user to enable
audio on the fly with xrandr, but turns audio on
automatically if radeon.audio=1 is set which is what
most users expect.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 79159b5..6456573 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -1658,9 +1658,12 @@
 			drm_object_attach_property(&radeon_connector->base.base,
 						      rdev->mode_info.underscan_vborder_property,
 						      0);
-			drm_object_attach_property(&radeon_connector->base.base,
-						   rdev->mode_info.audio_property,
-						   RADEON_AUDIO_DISABLE);
+			if (radeon_audio != 0)
+				drm_object_attach_property(&radeon_connector->base.base,
+							   rdev->mode_info.audio_property,
+							   (radeon_audio == 1) ?
+							   RADEON_AUDIO_AUTO :
+							   RADEON_AUDIO_DISABLE);
 			subpixel_order = SubPixelHorizontalRGB;
 			connector->interlace_allowed = true;
 			if (connector_type == DRM_MODE_CONNECTOR_HDMIB)
@@ -1754,10 +1757,12 @@
 							      rdev->mode_info.underscan_vborder_property,
 							      0);
 			}
-			if (ASIC_IS_DCE2(rdev)) {
+			if (ASIC_IS_DCE2(rdev) && (radeon_audio != 0)) {
 				drm_object_attach_property(&radeon_connector->base.base,
-							      rdev->mode_info.audio_property,
-							      RADEON_AUDIO_DISABLE);
+							   rdev->mode_info.audio_property,
+							   (radeon_audio == 1) ?
+							   RADEON_AUDIO_AUTO :
+							   RADEON_AUDIO_DISABLE);
 			}
 			if (connector_type == DRM_MODE_CONNECTOR_DVII) {
 				radeon_connector->dac_load_detect = true;
@@ -1799,10 +1804,12 @@
 							      rdev->mode_info.underscan_vborder_property,
 							      0);
 			}
-			if (ASIC_IS_DCE2(rdev)) {
+			if (ASIC_IS_DCE2(rdev) && (radeon_audio != 0)) {
 				drm_object_attach_property(&radeon_connector->base.base,
-							      rdev->mode_info.audio_property,
-							      RADEON_AUDIO_DISABLE);
+							   rdev->mode_info.audio_property,
+							   (radeon_audio == 1) ?
+							   RADEON_AUDIO_AUTO :
+							   RADEON_AUDIO_DISABLE);
 			}
 			subpixel_order = SubPixelHorizontalRGB;
 			connector->interlace_allowed = true;
@@ -1843,10 +1850,12 @@
 							      rdev->mode_info.underscan_vborder_property,
 							      0);
 			}
-			if (ASIC_IS_DCE2(rdev)) {
+			if (ASIC_IS_DCE2(rdev) && (radeon_audio != 0)) {
 				drm_object_attach_property(&radeon_connector->base.base,
-							      rdev->mode_info.audio_property,
-							      RADEON_AUDIO_DISABLE);
+							   rdev->mode_info.audio_property,
+							   (radeon_audio == 1) ?
+							   RADEON_AUDIO_AUTO :
+							   RADEON_AUDIO_DISABLE);
 			}
 			connector->interlace_allowed = true;
 			/* in theory with a DP to VGA converter... */