@@ -40,21 +40,25 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp)
i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
const unsigned int timeout_ms = 10;
u32 status;
- bool done;
+ int try;
-#define C (((status = intel_uncore_read_notrace(&i915->uncore, ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
- done = wait_event_timeout(i915->display.gmbus.wait_queue, C,
- msecs_to_jiffies_timeout(timeout_ms));
+ for (try = 0; try < 10; try++) {
+ status = intel_uncore_read_notrace(&i915->uncore, ch_ctl);
+ if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
+ break;
+ usleep_range(400, 500);
+ }
+ if (try == 3) {
+ status = intel_uncore_read_notrace(&i915->uncore, ch_ctl);
+ if ((status & DP_AUX_CH_CTL_SEND_BUSY) != 0)
+ drm_err(&i915->drm,
+ "%s: did not complete or timeout within %ums (status 0x%08x)\n",
+ intel_dp->aux.name, timeout_ms, status);
+ }
/* just trace the final value */
trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
- if (!done)
- drm_err(&i915->drm,
- "%s: did not complete or timeout within %ums (status 0x%08x)\n",
- intel_dp->aux.name, timeout_ms, status);
-#undef C
-
return status;
}
The busy timeout logic checks for the AUX BUSY, then waits for the timeout period and then after timeout reads the register for BUSY or Success. Instead replace interrupt with polling so as to read the AUX CTL register often before the timeout period. Looks like there might be some issue with interrupt-on-read. Hence changing the logic to polling read. v2: replace interrupt with polling read v3: use usleep_rang instead of msleep, updated commit msg Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com> --- drivers/gpu/drm/i915/display/intel_dp_aux.c | 24 ++++++++++++--------- 1 file changed, 14 insertions(+), 10 deletions(-)