[PATCH v2 1/2] drm/amd/display: Switch the custom "max bpc" property to the DRM prop

[Nicholas Kazlauskas]

[Why]
The custom "max bpc" property was added to limit color depth while the
DRM one was still being merged. It's been a few kernel versions since
then and this TODO was still sticking around.

[How]
Attach the DRM max bpc property to the connector and drop all of our
custom property management. Set the max bpc to 8 by default since
DRM defaults to the max in the range which would be 16 in this case.

No behavioral changes are intended with this patch, it should just be
a refactor.

Cc: Leo Li <sunpeng.li at amd.com>
Cc: Harry Wentland <harry.wentland at amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
Acked-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_display.c   |  4 ---
 drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h      |  2 --
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 29 ++++++++-----------
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h |  1 -
 4 files changed, 12 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index 4e944737b708..767ee6991ef4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -631,10 +631,6 @@ int amdgpu_display_modeset_create_props(struct amdgpu_device *adev)
 					 amdgpu_dither_enum_list, sz);
 
 	if (amdgpu_device_has_dc_support(adev)) {
-		adev->mode_info.max_bpc_property =
-			drm_property_create_range(adev->ddev, 0, "max bpc", 8, 16);
-		if (!adev->mode_info.max_bpc_property)
-			return -ENOMEM;
 		adev->mode_info.abm_level_property =
 			drm_property_create_range(adev->ddev, 0,
 						"abm level", 0, 4);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
index c7940af42f76..8bda00ce8816 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h
@@ -332,8 +332,6 @@ struct amdgpu_mode_info {
 	struct drm_property *audio_property;
 	/* FMT dithering */
 	struct drm_property *dither_property;
-	/* maximum number of bits per channel for monitor color */
-	struct drm_property *max_bpc_property;
 	/* Adaptive Backlight Modulation (power feature) */
 	struct drm_property *abm_level_property;
 	/* it is used to allow enablement of freesync mode */
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 4a1755bce96c..b8e88209ef5d 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3040,14 +3040,14 @@ static void update_stream_scaling_settings(const struct drm_display_mode *mode,
 static enum dc_color_depth
 convert_color_depth_from_display_info(const struct drm_connector *connector)
 {
-	struct dm_connector_state *dm_conn_state =
-		to_dm_connector_state(connector->state);
 	uint32_t bpc = connector->display_info.bpc;
 
-	/* TODO: Remove this when there's support for max_bpc in drm */
-	if (dm_conn_state && bpc > dm_conn_state->max_bpc)
-		/* Round down to nearest even number. */
-		bpc = dm_conn_state->max_bpc - (dm_conn_state->max_bpc & 1);
+	/* TODO: Use passed in state instead of the current state. */
+	if (connector->state) {
+		bpc = connector->state->max_bpc;
+		/* Round down to the nearest even number. */
+		bpc = bpc - (bpc & 1);
+	}
 
 	switch (bpc) {
 	case 0:
@@ -3689,9 +3689,6 @@ int amdgpu_dm_connector_atomic_set_property(struct drm_connector *connector,
 	} else if (property == adev->mode_info.underscan_property) {
 		dm_new_state->underscan_enable = val;
 		ret = 0;
-	} else if (property == adev->mode_info.max_bpc_property) {
-		dm_new_state->max_bpc = val;
-		ret = 0;
 	} else if (property == adev->mode_info.abm_level_property) {
 		dm_new_state->abm_level = val;
 		ret = 0;
@@ -3743,9 +3740,6 @@ int amdgpu_dm_connector_atomic_get_property(struct drm_connector *connector,
 	} else if (property == adev->mode_info.underscan_property) {
 		*val = dm_state->underscan_enable;
 		ret = 0;
-	} else if (property == adev->mode_info.max_bpc_property) {
-		*val = dm_state->max_bpc;
-		ret = 0;
 	} else if (property == adev->mode_info.abm_level_property) {
 		*val = dm_state->abm_level;
 		ret = 0;
@@ -3808,7 +3802,6 @@ void amdgpu_dm_connector_funcs_reset(struct drm_connector *connector)
 		state->underscan_enable = false;
 		state->underscan_hborder = 0;
 		state->underscan_vborder = 0;
-		state->max_bpc = 8;
 
 		__drm_atomic_helper_connector_reset(connector, &state->base);
 	}
@@ -3835,7 +3828,6 @@ amdgpu_dm_connector_atomic_duplicate_state(struct drm_connector *connector)
 	new_state->underscan_enable = state->underscan_enable;
 	new_state->underscan_hborder = state->underscan_hborder;
 	new_state->underscan_vborder = state->underscan_vborder;
-	new_state->max_bpc = state->max_bpc;
 
 	return &new_state->base;
 }
@@ -4756,9 +4748,12 @@ void amdgpu_dm_connector_init_helper(struct amdgpu_display_manager *dm,
 	drm_object_attach_property(&aconnector->base.base,
 				adev->mode_info.underscan_vborder_property,
 				0);
-	drm_object_attach_property(&aconnector->base.base,
-				adev->mode_info.max_bpc_property,
-				0);
+
+	drm_connector_attach_max_bpc_property(&aconnector->base, 8, 16);
+
+	/* This defaults to the max in the range, but we want 8bpc. */
+	aconnector->base.state->max_bpc = 8;
+	aconnector->base.state->max_requested_bpc = 8;
 
 	if (connector_type == DRM_MODE_CONNECTOR_eDP &&
 	    dc_is_dmcu_initialized(adev->dm.dc)) {
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
index 2cbc26f5d6a6..3395f2e4d564 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
@@ -304,7 +304,6 @@ struct dm_connector_state {
 	enum amdgpu_rmx_type scaling;
 	uint8_t underscan_vborder;
 	uint8_t underscan_hborder;
-	uint8_t max_bpc;
 	bool underscan_enable;
 	bool freesync_enable;
 	bool freesync_capable;
-- 
2.17.1