Quoting Kuogee Hsieh (2021-07-06 10:20:16)
Aux hardware calibration sequence requires resetting the aux controller in order for the new setting to take effect. However resetting the AUX controller will also clear HPD interrupt status which may accidentally cause pending unplug interrupt to get lost. Therefore reset aux controller only when link is in connection state when dp_aux_cmd_fifo_tx() fail. This fixes Link Layer CTS cases 4.2.1.1 and 4.2.1.2.
Signed-off-by: Kuogee Hsieh khsieh@codeaurora.org
drivers/gpu/drm/msm/dp/dp_aux.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c index 4a3293b..eb40d84 100644 --- a/drivers/gpu/drm/msm/dp/dp_aux.c +++ b/drivers/gpu/drm/msm/dp/dp_aux.c @@ -353,6 +353,9 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux, if (!(aux->retry_cnt % MAX_AUX_RETRIES)) dp_catalog_aux_update_cfg(aux->catalog); }
/* reset aux if link is in connected state */if (dp_catalog_link_is_connected(aux->catalog))
How do we avoid resetting aux when hpd is unplugged and then plugged back in during an aux transfer?
dp_catalog_aux_reset(aux->catalog); } else { aux->retry_cnt = 0; switch (aux->aux_error_num) {-- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project