[PATCH net v2] net: stmmac: propagate PTP init failures in __stmmac_open() and stmmac_resume()

@@ -601,7 +601,7 @@ static void stmmac_get_rx_hwtstamp(struct stmmac_priv *priv, struct dma_desc *p,
 	}
 }
 
-static void stmmac_update_subsecond_increment(struct stmmac_priv *priv)
+static int stmmac_update_subsecond_increment(struct stmmac_priv *priv)
 {
 	bool xmac = dwmac_is_xmac(priv->plat->core_type);
 	u32 sec_inc = 0;

@@ -625,7 +625,18 @@ static void stmmac_update_subsecond_increment(struct stmmac_priv *priv)
 	 */
 	temp = (u64)(temp << 32);
 	priv->default_addend = div_u64(temp, priv->plat->clk_ptp_rate);
-	stmmac_config_addend(priv, priv->ptpaddr, priv->default_addend);
+	return stmmac_config_addend(priv, priv->ptpaddr, priv->default_addend);
+}
+
+static bool stmmac_check_timestamp_cap(struct stmmac_priv *priv)
+{
+	if (!priv->dma_cap.time_stamp && !priv->dma_cap.atime_stamp)
+		return false;
+
+	if (!priv->plat->clk_ptp_rate)
+		return false;
+
+	return true;
 }
 
 /**

@@ -653,7 +664,7 @@ static int stmmac_hwtstamp_set(struct net_device *dev,
 	u32 ts_master_en = 0;
 	u32 ts_event_en = 0;
 
-	if (!(priv->dma_cap.time_stamp || priv->adv_ts)) {
+	if (!stmmac_check_timestamp_cap(priv)) {
 		NL_SET_ERR_MSG_MOD(extack, "No support for HW time stamping");
 		priv->hwts_tx_en = 0;
 		priv->hwts_rx_en = 0;

@@ -843,7 +854,7 @@ static int stmmac_hwtstamp_get(struct net_device *dev,
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
 
-	if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))
+	if (!stmmac_check_timestamp_cap(priv))
 		return -EOPNOTSUPP;
 
 	*config = priv->tstamp_config;

@@ -865,24 +876,21 @@ static int stmmac_init_tstamp_counter(struct stmmac_priv *priv,
 				      u32 systime_flags)
 {
 	struct timespec64 now;
-
-	if (!priv->plat->clk_ptp_rate) {
-		netdev_err(priv->dev, "Invalid PTP clock rate");
-		return -EINVAL;
-	}
+	int ret;
 
 	stmmac_config_hw_tstamping(priv, priv->ptpaddr, systime_flags);
 	priv->systime_flags = systime_flags;
 
-	stmmac_update_subsecond_increment(priv);
+	ret = stmmac_update_subsecond_increment(priv);
+	if (ret)
+		return ret;
 
 	/* initialize system time */
 	ktime_get_real_ts64(&now);
 
 	/* lower 32 bits of tv_sec are safe until y2106 */
-	stmmac_init_systime(priv, priv->ptpaddr, (u32)now.tv_sec, now.tv_nsec);
-
-	return 0;
+	return stmmac_init_systime(priv, priv->ptpaddr, (u32)now.tv_sec,
+				   now.tv_nsec);
 }
 
 /**

@@ -900,11 +908,6 @@ static int stmmac_init_timestamping(struct stmmac_priv *priv)
 	if (priv->plat->ptp_clk_freq_config)
 		priv->plat->ptp_clk_freq_config(priv);
 
-	if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp)) {
-		netdev_info(priv->dev, "PTP not supported by HW\n");
-		return -EOPNOTSUPP;
-	}
-
 	ret = stmmac_init_tstamp_counter(priv, STMMAC_HWTS_ACTIVE |
 					       PTP_TCR_TSCFUPDT);
 	if (ret) {

@@ -937,22 +940,39 @@ static int stmmac_init_timestamping(struct stmmac_priv *priv)
 	return 0;
 }
 
-static void stmmac_setup_ptp(struct stmmac_priv *priv)
+static int stmmac_setup_ptp(struct stmmac_priv *priv)
 {
 	int ret;
 
+	if (!stmmac_check_timestamp_cap(priv)) {
+		netdev_info(priv->dev, "PTP not supported\n");
+		return 0;
+	}
+
 	ret = clk_prepare_enable(priv->plat->clk_ptp_ref);
-	if (ret < 0)
+	if (ret < 0) {
 		netdev_warn(priv->dev,
 			    "failed to enable PTP reference clock: %pe\n",
 			    ERR_PTR(ret));
+		return ret;
+	}
 
-	if (stmmac_init_timestamping(priv) == 0)
-		stmmac_ptp_register(priv);
+	ret = stmmac_init_timestamping(priv);
+	if (ret) {
+		clk_disable_unprepare(priv->plat->clk_ptp_ref);
+		return ret;
+	}
+
+	stmmac_ptp_register(priv);
+
+	return 0;
 }
 
 static void stmmac_release_ptp(struct stmmac_priv *priv)
 {
+	if (!stmmac_check_timestamp_cap(priv))
+		return;
+
 	stmmac_ptp_unregister(priv);
 	clk_disable_unprepare(priv->plat->clk_ptp_ref);
 }

@@ -4161,10 +4181,12 @@ static int __stmmac_open(struct net_device *dev,
 	ret = stmmac_hw_setup(dev);
 	if (ret < 0) {
 		netdev_err(priv->dev, "%s: Hw setup failed\n", __func__);
-		goto init_error;
+		return ret;
 	}
 
-	stmmac_setup_ptp(priv);
+	ret = stmmac_setup_ptp(priv);
+	if (ret)
+		goto ptp_error;
 
 	stmmac_init_coalesce(priv);
 

@@ -4185,13 +4207,13 @@ static int __stmmac_open(struct net_device *dev,
 irq_error:
 	phylink_stop(priv->phylink);
 
-	stmmac_stop_all_dma(priv);
-
 	for (chan = 0; chan < priv->plat->tx_queues_to_use; chan++)
 		hrtimer_cancel(&priv->dma_conf.tx_queue[chan].txtimer);
 
 	stmmac_release_ptp(priv);
-init_error:
+ptp_error:
+	stmmac_stop_all_dma(priv);
+
 	return ret;
 }
 

@@ -8350,13 +8372,14 @@ int stmmac_resume(struct device *dev)
 	ret = stmmac_hw_setup(ndev);
 	if (ret < 0) {
 		netdev_err(priv->dev, "%s: Hw setup failed\n", __func__);
-		stmmac_legacy_serdes_power_down(priv);
-		mutex_unlock(&priv->lock);
-		rtnl_unlock();
-		return ret;
+		goto error_unlock;
 	}
 
-	stmmac_init_timestamping(priv);
+	if (stmmac_check_timestamp_cap(priv)) {
+		ret = stmmac_init_timestamping(priv);
+		if (ret)
+			goto error_stop_dma;
+	}
 
 	stmmac_init_coalesce(priv);
 	phylink_rx_clk_stop_block(priv->phylink);

@@ -8380,6 +8403,15 @@ int stmmac_resume(struct device *dev)
 	netif_device_attach(ndev);
 
 	return 0;
+
+error_stop_dma:
+	stmmac_stop_all_dma(priv);
+error_unlock:
+	stmmac_legacy_serdes_power_down(priv);
+	mutex_unlock(&priv->lock);
+	rtnl_unlock();
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(stmmac_resume);