[PATCH 11/20] drm/i915/dp: Reprobe connector if getting/acking device IRQs fails

[Imre Deak]

From: Imre Deak <imre.d...@gmail.com>

An AUX access failure during HPD IRQ handling should be handled by
falling back to a full connector detection, ensure that if the failure
happens while reading/acking a device service IRQ.

Signed-off-by: Imre Deak <imre.d...@gmail.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c 
b/drivers/gpu/drm/i915/display/intel_dp.c
index 7793a72983abd..7eb208d2c321b 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5393,16 +5393,20 @@ void intel_dp_check_link_state(struct intel_dp 
*intel_dp)
        intel_encoder_link_check_queue_work(encoder, 0);
 }
 
-static void intel_dp_check_device_service_irq(struct intel_dp *intel_dp)
+static bool intel_dp_check_device_service_irq(struct intel_dp *intel_dp)
 {
        struct intel_display *display = to_intel_display(intel_dp);
        u8 val;
 
        if (drm_dp_dpcd_readb(&intel_dp->aux,
-                             DP_DEVICE_SERVICE_IRQ_VECTOR, &val) != 1 || !val)
-               return;
+                             DP_DEVICE_SERVICE_IRQ_VECTOR, &val) != 1)
+               return true;
 
-       drm_dp_dpcd_writeb(&intel_dp->aux, DP_DEVICE_SERVICE_IRQ_VECTOR, val);
+       if (!val)
+               return false;
+
+       if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_DEVICE_SERVICE_IRQ_VECTOR, 
val) != 1)
+               return true;
 
        if (val & DP_AUTOMATED_TEST_REQUEST)
                intel_dp_test_request(intel_dp);
@@ -5412,6 +5416,8 @@ static void intel_dp_check_device_service_irq(struct 
intel_dp *intel_dp)
 
        if (val & DP_SINK_SPECIFIC_IRQ)
                drm_dbg_kms(display->drm, "Sink specific irq unhandled\n");
+
+       return false;
 }
 
 static bool intel_dp_check_link_service_irq(struct intel_dp *intel_dp)
@@ -5476,8 +5482,11 @@ intel_dp_short_pulse(struct intel_dp *intel_dp)
                /* No need to proceed if we are going to do full detect */
                return false;
 
-       intel_dp_check_device_service_irq(intel_dp);
-       reprobe_needed = intel_dp_check_link_service_irq(intel_dp);
+       if (intel_dp_check_device_service_irq(intel_dp))
+               reprobe_needed = true;
+
+       if (intel_dp_check_link_service_irq(intel_dp))
+               reprobe_needed = true;
 
        /* Handle CEC interrupts, if any */
        drm_dp_cec_irq(&intel_dp->aux);
-- 
2.44.2