When switching to drm_edid, we slightly changed how to get edid by
removing the possibility of getting them from dc_link when in aux
transaction mode. As MST doesn't initialize the connector with
`drm_connector_init_with_ddc()`, restore the original behavior to avoid
functional changes.
Fixes: 48edb2a4256e ("drm/amd/display: switch amdgpu_dm_connector to use struct drm_edid")
Signed-off-by: Melissa Wen <mwen@xxxxxxxxxx>
---
Hi,
So far, there is no reports about an issue related to this but I noticed
this potential functional change when investigating the previous
freesync problem. I'm not 100% clear if MST takes this path without
initializating connector->ddc, but I propose here to restore the
original behavior to avoid regressions.
Melissa
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
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 a8421c07b160..0cd22a6686a3 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7269,8 +7269,14 @@ static void amdgpu_dm_connector_funcs_force(struct drm_connector *connector)
struct dc_link *dc_link = aconnector->dc_link;
struct dc_sink *dc_em_sink = aconnector->dc_em_sink;
const struct drm_edid *drm_edid;
+ struct i2c_adapter *ddc;
- drm_edid = drm_edid_read(connector);
+ if (dc_link->aux_mode)
+ ddc = &aconnector->dm_dp_aux.aux.ddc;
+ else
+ ddc = &aconnector->i2c->base;
+
+ drm_edid = drm_edid_read_ddc(connector, ddc);
drm_edid_connector_update(connector, drm_edid);
if (!drm_edid) {
DRM_ERROR("No EDID found on connector: %s.\n", connector->name);
@@ -7315,14 +7321,21 @@ static int get_modes(struct drm_connector *connector)
static void create_eml_sink(struct amdgpu_dm_connector *aconnector)
{
struct drm_connector *connector = &aconnector->base;
+ struct dc_link *dc_link = aconnector->dc_link;
struct dc_sink_init_data init_params = {
.link = aconnector->dc_link,
.sink_signal = SIGNAL_TYPE_VIRTUAL
};
const struct drm_edid *drm_edid;
const struct edid *edid;
+ struct i2c_adapter *ddc;
- drm_edid = drm_edid_read(connector);
+ if (dc_link->aux_mode)
+ ddc = &aconnector->dm_dp_aux.aux.ddc;
+ else
+ ddc = &aconnector->i2c->base;
+
+ drm_edid = drm_edid_read_ddc(connector, ddc);
drm_edid_connector_update(connector, drm_edid);
if (!drm_edid) {
DRM_ERROR("No EDID found on connector: %s.\n", connector->name);
--
2.47.2
