diff options
Diffstat (limited to 'drivers/gpu/drm/drm_dp_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 62 |
1 files changed, 60 insertions, 2 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index a5364b5192b8..a4b98f8055f4 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -362,6 +362,65 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, EXPORT_SYMBOL(drm_dp_dpcd_read_link_status); /** + * drm_dp_send_real_edid_checksum() - send back real edid checksum value + * @aux: DisplayPort AUX channel + * @real_edid_checksum: real edid checksum for the last block + * + * Returns: + * True on success + */ +bool drm_dp_send_real_edid_checksum(struct drm_dp_aux *aux, + u8 real_edid_checksum) +{ + u8 link_edid_read = 0, auto_test_req = 0, test_resp = 0; + + if (drm_dp_dpcd_read(aux, DP_DEVICE_SERVICE_IRQ_VECTOR, + &auto_test_req, 1) < 1) { + DRM_ERROR("DPCD failed read at register 0x%x\n", + DP_DEVICE_SERVICE_IRQ_VECTOR); + return false; + } + auto_test_req &= DP_AUTOMATED_TEST_REQUEST; + + if (drm_dp_dpcd_read(aux, DP_TEST_REQUEST, &link_edid_read, 1) < 1) { + DRM_ERROR("DPCD failed read at register 0x%x\n", + DP_TEST_REQUEST); + return false; + } + link_edid_read &= DP_TEST_LINK_EDID_READ; + + if (!auto_test_req || !link_edid_read) { + DRM_DEBUG_KMS("Source DUT does not support TEST_EDID_READ\n"); + return false; + } + + if (drm_dp_dpcd_write(aux, DP_DEVICE_SERVICE_IRQ_VECTOR, + &auto_test_req, 1) < 1) { + DRM_ERROR("DPCD failed write at register 0x%x\n", + DP_DEVICE_SERVICE_IRQ_VECTOR); + return false; + } + + /* send back checksum for the last edid extension block data */ + if (drm_dp_dpcd_write(aux, DP_TEST_EDID_CHECKSUM, + &real_edid_checksum, 1) < 1) { + DRM_ERROR("DPCD failed write at register 0x%x\n", + DP_TEST_EDID_CHECKSUM); + return false; + } + + test_resp |= DP_TEST_EDID_CHECKSUM_WRITE; + if (drm_dp_dpcd_write(aux, DP_TEST_RESPONSE, &test_resp, 1) < 1) { + DRM_ERROR("DPCD failed write at register 0x%x\n", + DP_TEST_RESPONSE); + return false; + } + + return true; +} +EXPORT_SYMBOL(drm_dp_send_real_edid_checksum); + +/** * drm_dp_downstream_max_clock() - extract branch device max * pixel rate for legacy VGA * converter or max TMDS clock @@ -470,8 +529,7 @@ void drm_dp_downstream_debug(struct seq_file *m, int len; uint8_t rev[2]; int type = port_cap[0] & DP_DS_PORT_TYPE_MASK; - bool branch_device = dpcd[DP_DOWNSTREAMPORT_PRESENT] & - DP_DWN_STRM_PORT_PRESENT; + bool branch_device = drm_dp_is_branch(dpcd); seq_printf(m, "\tDP branch device present: %s\n", branch_device ? "yes" : "no"); |