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authorMika Kahola <mika.kahola@intel.com>2016-09-09 14:10:53 +0300
committerJani Nikula <jani.nikula@intel.com>2016-09-15 14:50:27 +0300
commit0e390a33a668f97ea3ffa7c6ceb4266e1b39450a (patch)
treecf9c192cf4f35952d10488b4a087d6bc5d07e1df /drivers/gpu/drm/i915/intel_dp.c
parentb633958587ddd47fd9fe3d0d34d51f769b51d77b (diff)
drm/i915: Read DP branch device HW revision
HW revision is mandatory field for DisplayPort branch devices. This is defined in DPCD register field 0x509. v2: move drm_dp_ds_revision structure to be part of drm_dp_link structure (Daniel) v3: remove dependency to drm_dp_helper but instead parse DPCD and print HW revision info to dmesg (Ville) Reviewed-by: Jim Bride <jim.bride@linux.intel.com> Signed-off-by: Mika Kahola <mika.kahola@intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1473419458-17080-8-git-send-email-mika.kahola@intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp.c')
-rw-r--r--drivers/gpu/drm/i915/intel_dp.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index c69ad13aab42..bb0417c52154 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1419,6 +1419,25 @@ static void intel_dp_print_rates(struct intel_dp *intel_dp)
DRM_DEBUG_KMS("common rates: %s\n", str);
}
+static void intel_dp_print_hw_revision(struct intel_dp *intel_dp)
+{
+ uint8_t rev;
+ int len;
+
+ if ((drm_debug & DRM_UT_KMS) == 0)
+ return;
+
+ if (!(intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] &
+ DP_DWN_STRM_PORT_PRESENT))
+ return;
+
+ len = drm_dp_dpcd_read(&intel_dp->aux, DP_BRANCH_HW_REV, &rev, 1);
+ if (len < 0)
+ return;
+
+ DRM_DEBUG_KMS("sink hw revision: %d.%d\n", (rev & 0xf0) >> 4, rev & 0xf);
+}
+
static int rate_to_index(int find, const int *rates)
{
int i = 0;
@@ -4312,6 +4331,8 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
intel_dp_probe_oui(intel_dp);
+ intel_dp_print_hw_revision(intel_dp);
+
intel_dp_configure_mst(intel_dp);
if (intel_dp->is_mst) {