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[v5,3/8] drm/i915/dp: Initialize the source OUI write timestamp always

Message ID 20241025160259.3088727-4-imre.deak@intel.com (mailing list archive)
State New
Headers show
Series drm/i915: Write source OUI for non-eDP sinks | expand

Commit Message

Imre Deak Oct. 25, 2024, 4:02 p.m. UTC 
If the source OUI DPCD register value matches the expected Intel OUI
value, the write timestamp doesn't get updated leaving it at the 0
initial value if the OUI wasn't written before. This can lead to an
incorrect wait duration in intel_dp_wait_source_oui(), since jiffies is
not inited to 0 in general (on a 32 bit system INITIAL_JIFFIES is set to
5 minutes ahead of wrap-around). Fix this by intializing the write
timestamp in the above case as well.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 69a4e9c86d386..778cc33d3c690 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -3415,8 +3415,11 @@  intel_edp_init_source_oui(struct intel_dp *intel_dp, bool careful)
 		if (drm_dp_dpcd_read(&intel_dp->aux, DP_SOURCE_OUI, buf, sizeof(buf)) < 0)
 			drm_err(&i915->drm, "Failed to read source OUI\n");
 
-		if (memcmp(oui, buf, sizeof(oui)) == 0)
+		if (memcmp(oui, buf, sizeof(oui)) == 0) {
+			/* Assume the OUI was written now. */
+			intel_dp->last_oui_write = jiffies;
 			return;
+		}
 	}
 
 	if (drm_dp_dpcd_write(&intel_dp->aux, DP_SOURCE_OUI, oui, sizeof(oui)) < 0)