From 559be30cb74d6a9f3345f78a0cf3a02a564d8eef Mon Sep 17 00:00:00 2001 From: Todd Previte Date: Mon, 4 May 2015 07:48:20 -0700 Subject: [PATCH] drm/i915: Implement the intel_dp_autotest_edid function for DP EDID complaince tests Updates the EDID compliance test function to perform the analyze and react to the EDID data read as a result of a hot plug event. The results of this analysis are handed off to userspace so that the userspace app can set the display mode appropriately for the test result/response. The compliance_test_active flag now appears at the end of the individual test handling functions. This is so that the kernel-side operations can be completed without the risk of interruption from the userspace app that is polling on that flag. V2: - Addressed mailing list feedback - Removed excess debug messages - Removed extraneous comments - Fixed formatting issues (line length > 80) - Updated the debug message in compute_edid_checksum to output hex values instead of decimal V3: - Addressed more list feedback - Added the test_active flag to the autotest function - Removed test_active flag from handler - Added failsafe check on the compliance test active flag at the end of the test handler - Fixed checkpatch.pl issues V4: - Removed the checksum computation function and its use as it has been rendered superfluous by changes to the core DRM EDID functions - Updated to use the raw header corruption detection mechanism - Moved the declaration of the test_data variable here V5: - Update test active flag variable name to match the change in the first patch of the series. - Relocated the test active flag declaration and initialization to this patch V6: - Updated to use the new flag for raw EDID header corruption - Removed the extra EDID read from the autotest function - Added the edid_checksum variable to struct intel_dp so that the autotest function can write it to the sink device - Moved the update to the hpd_pulse function to another patch - Removed extraneous constants V7: - Fixed erroneous placement of the checksum assignment. In some cases such as when the EDID read fails and is NULL, this causes a NULL ptr dereference in the kernel. Bad news. Fixed now. V8: - Updated to support the kfree() on the EDID data added previously V9: - Updated for the long_hpd flag propagation V10: - Updated to use actual checksum from the EDID read that occurs during normal hot plug path execution - Removed variables from intel_dp struct that are no longer needed - Updated the patch subject to more closely match the nature and contents of the patch - Fixed formatting problem (long line) V11: - Removed extra debug messages - Updated comments to be more informative - Removed extra variable V12: - Removed the 4 bit offset of the resolution setting in compliance data - Changed to DRM_DEBUG_KMS instead of DRM_DEBUG_DRIVER Signed-off-by: Todd Previte Reviewed-by: Paulo Zanoni Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_dp.c | 42 ++++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_drv.h | 2 ++ 2 files changed, 44 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 91c8bf3cf62b..d0a88602efab 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -41,6 +41,12 @@ #define DP_LINK_CHECK_TIMEOUT (10 * 1000) +/* Compliance test status bits */ +#define INTEL_DP_RESOLUTION_SHIFT_MASK 0 +#define INTEL_DP_RESOLUTION_PREFERRED (1 << INTEL_DP_RESOLUTION_SHIFT_MASK) +#define INTEL_DP_RESOLUTION_STANDARD (2 << INTEL_DP_RESOLUTION_SHIFT_MASK) +#define INTEL_DP_RESOLUTION_FAILSAFE (3 << INTEL_DP_RESOLUTION_SHIFT_MASK) + struct dp_link_dpll { int link_bw; struct dpll dpll; @@ -4079,6 +4085,39 @@ static uint8_t intel_dp_autotest_video_pattern(struct intel_dp *intel_dp) static uint8_t intel_dp_autotest_edid(struct intel_dp *intel_dp) { uint8_t test_result = DP_TEST_NAK; + struct intel_connector *intel_connector = intel_dp->attached_connector; + struct drm_connector *connector = &intel_connector->base; + + if (intel_connector->detect_edid == NULL || + connector->edid_corrupt == 1 || + intel_dp->aux.i2c_defer_count > 6) { + /* Check EDID read for NACKs, DEFERs and corruption + * (DP CTS 1.2 Core r1.1) + * 4.2.2.4 : Failed EDID read, I2C_NAK + * 4.2.2.5 : Failed EDID read, I2C_DEFER + * 4.2.2.6 : EDID corruption detected + * Use failsafe mode for all cases + */ + if (intel_dp->aux.i2c_nack_count > 0 || + intel_dp->aux.i2c_defer_count > 0) + DRM_DEBUG_KMS("EDID read had %d NACKs, %d DEFERs\n", + intel_dp->aux.i2c_nack_count, + intel_dp->aux.i2c_defer_count); + intel_dp->compliance_test_data = INTEL_DP_RESOLUTION_FAILSAFE; + } else { + if (!drm_dp_dpcd_write(&intel_dp->aux, + DP_TEST_EDID_CHECKSUM, + &intel_connector->detect_edid->checksum, + 1)); + DRM_DEBUG_KMS("Failed to write EDID checksum\n"); + + test_result = DP_TEST_ACK | DP_TEST_EDID_CHECKSUM_WRITE; + intel_dp->compliance_test_data = INTEL_DP_RESOLUTION_STANDARD; + } + + /* Set test active flag here so userspace doesn't interrupt things */ + intel_dp->compliance_test_active = 1; + return test_result; } @@ -4094,7 +4133,10 @@ static void intel_dp_handle_test_request(struct intel_dp *intel_dp) uint8_t rxdata = 0; int status = 0; + intel_dp->compliance_test_active = 0; intel_dp->compliance_test_type = 0; + intel_dp->compliance_test_data = 0; + intel_dp->aux.i2c_nack_count = 0; intel_dp->aux.i2c_defer_count = 0; diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index cf701ed26478..da553af78a65 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -740,6 +740,8 @@ struct intel_dp { /* Displayport compliance testing */ unsigned long compliance_test_type; + unsigned long compliance_test_data; + bool compliance_test_active; }; struct intel_digital_port {