diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index e37c7a037538..389eabf898ad 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -2922,6 +2922,35 @@ intel_dp_probe_oui(struct intel_dp *intel_dp) edp_panel_vdd_off(intel_dp, false); } +int intel_dp_sink_crc(struct intel_dp *intel_dp, u8 *crc) +{ + struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp); + struct drm_device *dev = intel_dig_port->base.base.dev; + struct intel_crtc *intel_crtc = + to_intel_crtc(intel_dig_port->base.base.crtc); + u8 buf[1]; + + if (!intel_dp_aux_native_read(intel_dp, DP_TEST_SINK_MISC, buf, 1)) + return -EAGAIN; + + if (!(buf[0] & DP_TEST_CRC_SUPPORTED)) + return -ENOTTY; + + if (!intel_dp_aux_native_write_1(intel_dp, DP_TEST_SINK, + DP_TEST_SINK_START)) + return -EAGAIN; + + /* Wait 2 vblanks to be sure we will have the correct CRC value */ + intel_wait_for_vblank(dev, intel_crtc->pipe); + intel_wait_for_vblank(dev, intel_crtc->pipe); + + if (!intel_dp_aux_native_read(intel_dp, DP_TEST_CRC_R_CR, crc, 6)) + return -EAGAIN; + + intel_dp_aux_native_write_1(intel_dp, DP_TEST_SINK, 0); + return 0; +} + static bool intel_dp_get_sink_irq(struct intel_dp *intel_dp, u8 *sink_irq_vector) { |