Add a meaningful return to intel_dp_read_dsc_dpcd. This is to avoid unwanted DPCD reads which are not needed once we know DSC DPCD read fails. To do this convert drm_dp_dpcd_read to drm_dp_dpcd_read_data which returns a meaningful error which can be propogated up when all bits are not read. While we are at it convert the drm_err in intel_dp_read_dsc_dpcd to drm_dbg_kms. This is because we do not want a hard ERROR when we call this function, during the intel_dp_detect phase since AUX may not be up, it is expected to fail but we do not expect a failure in read when we call intel_dp_dsc_get_sink_cap so we move the drm_err there.
Signed-off-by: Suraj Kandpal <[email protected]> --- V1 -> V2: -Commit message fixup (Jani) -Convert drm_dp_dpcd_read to drm_dp_dpcd_read_data (Jani) -Propogate the error sent by drm_dp_dpcd_read_data up (Jani) -Use %pe and ERR_PTR() to log the extact error (Jani) drivers/gpu/drm/i915/display/intel_dp.c | 33 ++++++++++++++++--------- 1 file changed, 21 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 79fd3b8d8b25..ec277dcb24bc 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -4281,20 +4281,24 @@ static bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp) return dprx & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED; } -static void intel_dp_read_dsc_dpcd(struct drm_dp_aux *aux, - u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE]) -{ - if (drm_dp_dpcd_read(aux, DP_DSC_SUPPORT, dsc_dpcd, - DP_DSC_RECEIVER_CAP_SIZE) < 0) { - drm_err(aux->drm_dev, - "Failed to read DPCD register 0x%x\n", - DP_DSC_SUPPORT); - return; +static int intel_dp_read_dsc_dpcd(struct drm_dp_aux *aux, + u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE]) +{ + int ret; + + ret = drm_dp_dpcd_read_data(aux, DP_DSC_SUPPORT, dsc_dpcd, + DP_DSC_RECEIVER_CAP_SIZE); + if (ret) { + drm_dbg_kms(aux->drm_dev, + "Could not read DSC DPCD register 0x%x Error: %pe\n", + DP_DSC_SUPPORT, ERR_PTR(ret)); + return ret; } drm_dbg_kms(aux->drm_dev, "DSC DPCD: %*ph\n", DP_DSC_RECEIVER_CAP_SIZE, dsc_dpcd); + return 0; } static void init_dsc_overall_throughput_limits(struct intel_connector *connector, bool is_branch) @@ -4345,8 +4349,11 @@ void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, if (dpcd_rev < DP_DPCD_REV_14) return; - intel_dp_read_dsc_dpcd(connector->dp.dsc_decompression_aux, - connector->dp.dsc_dpcd); + if (intel_dp_read_dsc_dpcd(connector->dp.dsc_decompression_aux, + connector->dp.dsc_dpcd) < 0) { + drm_err(display->drm, "Failed to read DSC DPCD register\n"); + return; + } if (drm_dp_dpcd_readb(connector->dp.dsc_decompression_aux, DP_FEC_CAPABILITY, &connector->dp.fec_capability) < 0) { @@ -4376,7 +4383,9 @@ static void intel_edp_get_dsc_sink_cap(u8 edp_dpcd_rev, struct intel_connector * if (edp_dpcd_rev < DP_EDP_14) return; - intel_dp_read_dsc_dpcd(connector->dp.dsc_decompression_aux, connector->dp.dsc_dpcd); + if (intel_dp_read_dsc_dpcd(connector->dp.dsc_decompression_aux, + connector->dp.dsc_dpcd) < 0) + return; if (connector->dp.dsc_dpcd[0] & DP_DSC_DECOMPRESSION_IS_SUPPORTED) init_dsc_overall_throughput_limits(connector, false); -- 2.34.1
