drm/bridge: analogix_dp: Add support for &drm_dp_aux.wait_hpd_asserted()

Add analogix_dpaux_wait_hpd_asserted() to help confirm the HPD state
before doing AUX transfers.

Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20250310104114.2608063-8-damon.ding@rock-chips.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 84ad34f712440b0a46480c088b90e2777effe960..ab73e1a82b1522c744b80066a648d80046b130a3 100644 (file)
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1540,6 +1540,26 @@ out:
        return ret;
 }
 
+static int analogix_dpaux_wait_hpd_asserted(struct drm_dp_aux *aux, unsigned long wait_us)
+{
+       struct analogix_dp_device *dp = to_dp(aux);
+       int val;
+       int ret;
+
+       if (dp->force_hpd)
+               return 0;
+
+       pm_runtime_get_sync(dp->dev);
+
+       ret = readx_poll_timeout(analogix_dp_get_plug_in_status, dp, val, !val,
+                                wait_us / 100, wait_us);
+
+       pm_runtime_mark_last_busy(dp->dev);
+       pm_runtime_put_autosuspend(dp->dev);
+
+       return ret;
+}
+
 struct analogix_dp_device *
 analogix_dp_probe(struct device *dev, struct analogix_dp_plat_data *plat_data)
 {
@@ -1648,6 +1668,7 @@ analogix_dp_probe(struct device *dev, struct analogix_dp_plat_data *plat_data)
 
        dp->aux.name = "DP-AUX";
        dp->aux.transfer = analogix_dpaux_transfer;
+       dp->aux.wait_hpd_asserted = analogix_dpaux_wait_hpd_asserted;
        dp->aux.dev = dp->dev;
        drm_dp_aux_init(&dp->aux);