[PATCH 01/10] drm/i915: Add automated testing support for Displayport compliance testing

Todd Previte
2015-04-15T15:39:03Z

Add the skeleton framework for supporting automation for Displayport compliance
testing. This patch adds the necessary framework for the source device to
appropriately respond to test automation requests from a sink device.

V2:
- Addressed previous mailing list feedback
- Fixed compilation issue (struct members declared in a later patch)
- Updated debug messages to be more accurate
- Added status checks for the DPCD read/write calls
- Removed excess comments and debug messages
- Fixed debug message compilation warnings
- Fixed compilation issue with missing variables
- Updated link training autotest to ACK

V3:
- Fixed the checks on the DPCD return code to be <= 0
rather than != 0
- Removed extraneous assignment of a NAK return code in the
DPCD read failure case
- Changed the return in the DPCD read failure case to a goto
to the exit point where the status code is written to the sink
- Removed FAUX test case since it's deprecated now
- Removed the compliance flag assignment in handle_test_request

V4:
- Moved declaration of type_type here
- Removed declaration of test_data (moved to a later patch)
- Added reset to 0 for compliance test variables

V5:
- Moved test_active variable declaration and initialization out of
this patch and into the patch where it's used
- Changed variable name compliance_testing_active to
compliance_test_active to unify the naming convention
- Added initialization for compliance_test_type variable

Signed-off-by: Todd Previte <tprevite@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
drivers/gpu/drm/i915/intel_dp.c | 75 +++++++++++++++++++++++++++++++++++++---
drivers/gpu/drm/i915/intel_drv.h | 3 ++
2 files changed, 74 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 14cdd00..263eff3 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3970,11 +3970,78 @@ intel_dp_get_sink_irq_esi(struct intel_dp *intel_dp, u8 *sink_irq_vector)
return true;
}

-static void
-intel_dp_handle_test_request(struct intel_dp *intel_dp)
+static uint8_t intel_dp_autotest_link_training(struct intel_dp *intel_dp)
+{
+ uint8_t test_result = DP_TEST_ACK;
+ return test_result;
+}
+
+static uint8_t intel_dp_autotest_video_pattern(struct intel_dp *intel_dp)
+{
+ uint8_t test_result = DP_TEST_NAK;
+ return test_result;
+}
+
+static uint8_t intel_dp_autotest_edid(struct intel_dp *intel_dp)
+{
+ uint8_t test_result = DP_TEST_NAK;
+ return test_result;
+}
+
+static uint8_t intel_dp_autotest_phy_pattern(struct intel_dp *intel_dp)
+{
+ uint8_t test_result = DP_TEST_NAK;
+ return test_result;
+}
+
+static void intel_dp_handle_test_request(struct intel_dp *intel_dp)
{
- /* NAK by default */
- drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_RESPONSE, DP_TEST_NAK);
+ uint8_t response = DP_TEST_NAK;
+ uint8_t rxdata = 0;
+ int status = 0;
+
+ intel_dp->compliance_test_type = 0;
+ intel_dp->aux.i2c_nack_count = 0;
+ intel_dp->aux.i2c_defer_count = 0;
+
+ status = drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_REQUEST, &rxdata, 1);
+ if (status <= 0) {
+ DRM_DEBUG_KMS("Could not read test request from sink\n");
+ goto update_status;
+ }
+
+ switch (rxdata) {
+ case DP_TEST_LINK_TRAINING:
+ DRM_DEBUG_KMS("LINK_TRAINING test requested\n");
+ intel_dp->compliance_test_type = DP_TEST_LINK_TRAINING;
+ response = intel_dp_autotest_link_training(intel_dp);
+ break;
+ case DP_TEST_LINK_VIDEO_PATTERN:
+ DRM_DEBUG_KMS("TEST_PATTERN test requested\n");
+ intel_dp->compliance_test_type = DP_TEST_LINK_VIDEO_PATTERN;
+ response = intel_dp_autotest_video_pattern(intel_dp);
+ break;
+ case DP_TEST_LINK_EDID_READ:
+ DRM_DEBUG_KMS("EDID test requested\n");
+ intel_dp->compliance_test_type = DP_TEST_LINK_EDID_READ;
+ response = intel_dp_autotest_edid(intel_dp);
+ break;
+ case DP_TEST_LINK_PHY_TEST_PATTERN:
+ DRM_DEBUG_KMS("PHY_PATTERN test requested\n");
+ intel_dp->compliance_test_type = DP_TEST_LINK_PHY_TEST_PATTERN;
+ response = intel_dp_autotest_phy_pattern(intel_dp);
+ break;
+ default:
+ DRM_DEBUG_KMS("Invalid test request '%02x'\n", rxdata);
+ break;
+ }
+
+update_status:
+ status = drm_dp_dpcd_write(&intel_dp->aux,
+ DP_TEST_RESPONSE,
+ &response, 1);
+ if (status <= 0)
+ DRM_DEBUG_KMS("Could not write test response to sink\n");
}

static int
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 6a2ee0c..a4675fa 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -739,6 +739,9 @@ struct intel_dp {
bool has_aux_irq,
int send_bytes,
uint32_t aux_clock_divider);
+
+ /* Displayport compliance testing */
+ unsigned long compliance_test_type;
};

struct intel_digital_port {