drm/bridge: anx7625: Add wait_hpd_asserted() callback

Move hpd polling check into wait_hpd_asserted() callback. For the cases
that aux transfer function wasn't used, do hpd polling check after pm
runtime resume, which will power on the bridge.
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Xin Ji <xji@analogixsemi.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220706125254.2474095-5-hsinyi@chromium.org

drivers/gpu/drm/bridge/analogix/anx7625.c

@@ -1443,23 +1443,24 @@ static int anx7625_read_hpd_status_p0(struct anx7625_data *ctx)
 	return anx7625_reg_read(ctx, ctx->i2c.rx_p0_client, SYSTEM_STSTUS);
 }
 
-static void anx7625_hpd_polling(struct anx7625_data *ctx)
+static int _anx7625_hpd_polling(struct anx7625_data *ctx,
+				unsigned long wait_us)
 {
 	int ret, val;
 	struct device *dev = &ctx->client->dev;
 
 	/* Interrupt mode, no need poll HPD status, just return */
 	if (ctx->pdata.intp_irq)
-		return;
+		return 0;
 
 	ret = readx_poll_timeout(anx7625_read_hpd_status_p0,
 				 ctx, val,
 				 ((val & HPD_STATUS) || (val < 0)),
-				 5000,
-				 5000 * 100);
+				 wait_us / 100,
+				 wait_us);
 	if (ret) {
 		DRM_DEV_ERROR(dev, "no hpd.\n");
-		return;
+		return ret;
 	}
 
 	DRM_DEV_DEBUG_DRIVER(dev, "system status: 0x%x. HPD raise up.\n", val);
@@ -1472,6 +1473,23 @@ static void anx7625_hpd_polling(struct anx7625_data *ctx)
 
 	if (!ctx->pdata.panel_bridge && ctx->bridge_attached)
 		drm_helper_hpd_irq_event(ctx->bridge.dev);
+
+	return 0;
+}
+
+static int anx7625_wait_hpd_asserted(struct drm_dp_aux *aux,
+				     unsigned long wait_us)
+{
+	struct anx7625_data *ctx = container_of(aux, struct anx7625_data, aux);
+	struct device *dev = &ctx->client->dev;
+	int ret;
+
+	pm_runtime_get_sync(dev);
+	ret = _anx7625_hpd_polling(ctx, wait_us);
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
+	return ret;
 }
 
 static void anx7625_remove_edid(struct anx7625_data *ctx)
@@ -1741,6 +1759,7 @@ static struct edid *anx7625_get_edid(struct anx7625_data *ctx)
 	}
 
 	pm_runtime_get_sync(dev);
+	_anx7625_hpd_polling(ctx, 5000 * 100);
 	edid_num = sp_tx_edid_read(ctx, p_edid->edid_raw_data);
 	pm_runtime_put_sync(dev);
 
@@ -2378,6 +2397,7 @@ static void anx7625_bridge_atomic_enable(struct drm_bridge *bridge,
 	ctx->connector = connector;
 
 	pm_runtime_get_sync(dev);
+	_anx7625_hpd_polling(ctx, 5000 * 100);
 
 	anx7625_dp_start(ctx);
 }
@@ -2497,7 +2517,6 @@ static int __maybe_unused anx7625_runtime_pm_resume(struct device *dev)
 	mutex_lock(&ctx->lock);
 
 	anx7625_power_on_init(ctx);
-	anx7625_hpd_polling(ctx);
 
 	mutex_unlock(&ctx->lock);
 
@@ -2589,6 +2608,7 @@ static int anx7625_i2c_probe(struct i2c_client *client,
 	platform->aux.name = "anx7625-aux";
 	platform->aux.dev = dev;
 	platform->aux.transfer = anx7625_aux_transfer;
+	platform->aux.wait_hpd_asserted = anx7625_wait_hpd_asserted;
 	drm_dp_aux_init(&platform->aux);
 
 	if (anx7625_register_i2c_dummy_clients(platform, client) != 0) {
@@ -2617,6 +2637,7 @@ static int anx7625_i2c_probe(struct i2c_client *client,
 	if (!platform->pdata.low_power_mode) {
 		anx7625_disable_pd_protocol(platform);
 		pm_runtime_get_sync(dev);
+		_anx7625_hpd_polling(platform, 5000 * 100);
 	}
 
 	/* Add work function */