diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 3618d29c79a24d2404688a11b5964aac06ecd451..09292193dafe0b28466e37061acc7bee25e348f5 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -258,6 +258,17 @@ drm_do_probe_ddc_edid(struct i2c_adapter *adapter, unsigned char *buf, return ret == 2 ? 0 : -1; } +static bool drm_edid_is_zero(u8 *in_edid, int length) +{ + int i; + u32 *raw_edid = (u32 *)in_edid; + + for (i = 0; i < length / 4; i++) + if (*(raw_edid + i) != 0) + return false; + return true; +} + static u8 * drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter) { @@ -273,6 +284,10 @@ drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter) goto out; if (drm_edid_block_valid(block)) break; + if (i == 0 && drm_edid_is_zero(block, EDID_LENGTH)) { + connector->null_edid_counter++; + goto carp; + } } if (i == 4) goto carp; diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c index 9c2929c7e79f9cf3390a8171416eab8d312148fa..c04e18ee8a8774c495ed187d0b3a3f828178cb22 100644 --- a/drivers/gpu/drm/radeon/radeon_connectors.c +++ b/drivers/gpu/drm/radeon/radeon_connectors.c @@ -836,6 +836,13 @@ radeon_dvi_detect(struct drm_connector *connector, bool force) if (!radeon_connector->edid) { DRM_ERROR("%s: probed a monitor but no|invalid EDID\n", drm_get_connector_name(connector)); + /* rs690 seems to have a problem with connectors not existing and always + * return a block of 0's. If we see this just stop polling on this output */ + if ((rdev->family == CHIP_RS690 || rdev->family == CHIP_RS740) && radeon_connector->base.null_edid_counter) { + ret = connector_status_disconnected; + DRM_ERROR("%s: detected RS690 floating bus bug, stopping ddc detect\n", drm_get_connector_name(connector)); + radeon_connector->ddc_bus = NULL; + } } else { radeon_connector->use_digital = !!(radeon_connector->edid->input & DRM_EDID_INPUT_DIGITAL); diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 9573e0ce312080caf9bcbcb72cd804e2ed200871..33d12f87f0e01735d41a800a73b7ea5ddc9b31a6 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -520,6 +520,8 @@ struct drm_connector { uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER]; uint32_t force_encoder_id; struct drm_encoder *encoder; /* currently active encoder */ + + int null_edid_counter; /* needed to workaround some HW bugs where we get all 0s */ }; /**