rswitch: Add PM ops

Add PM ops for Suspend to Idle. When the system suspended,
the Ethernet Serdes's clock will be stopped. So, this driver needs
to re-initialize the Ethernet Serdes by phy_init() in
renesas_eth_sw_resume(). Otherwise, timeout happened in phy_power_on().
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/renesas/rswitch.c

@@ -17,6 +17,7 @@
 #include <linux/of_net.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/rtnetlink.h>
 #include <linux/slab.h>
@@ -1315,6 +1316,7 @@ static int rswitch_phy_device_init(struct rswitch_device *rdev)
 	if (!phydev)
 		goto out;
 	__set_bit(rdev->etha->phy_interface, phydev->host_interfaces);
+	phydev->mac_managed_pm = true;
 
 	phydev = of_phy_connect(rdev->ndev, phy, rswitch_adjust_link, 0,
 				rdev->etha->phy_interface);
@@ -1995,11 +1997,52 @@ static void renesas_eth_sw_remove(struct platform_device *pdev)
 	platform_set_drvdata(pdev, NULL);
 }
 
+static int renesas_eth_sw_suspend(struct device *dev)
+{
+	struct rswitch_private *priv = dev_get_drvdata(dev);
+	struct net_device *ndev;
+	unsigned int i;
+
+	rswitch_for_each_enabled_port(priv, i) {
+		ndev = priv->rdev[i]->ndev;
+		if (netif_running(ndev)) {
+			netif_device_detach(ndev);
+			rswitch_stop(ndev);
+		}
+		if (priv->rdev[i]->serdes->init_count)
+			phy_exit(priv->rdev[i]->serdes);
+	}
+
+	return 0;
+}
+
+static int renesas_eth_sw_resume(struct device *dev)
+{
+	struct rswitch_private *priv = dev_get_drvdata(dev);
+	struct net_device *ndev;
+	unsigned int i;
+
+	rswitch_for_each_enabled_port(priv, i) {
+		phy_init(priv->rdev[i]->serdes);
+		ndev = priv->rdev[i]->ndev;
+		if (netif_running(ndev)) {
+			rswitch_open(ndev);
+			netif_device_attach(ndev);
+		}
+	}
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(renesas_eth_sw_pm_ops, renesas_eth_sw_suspend,
+				renesas_eth_sw_resume);
+
 static struct platform_driver renesas_eth_sw_driver_platform = {
 	.probe = renesas_eth_sw_probe,
 	.remove_new = renesas_eth_sw_remove,
 	.driver = {
 		.name = "renesas_eth_sw",
+		.pm = pm_sleep_ptr(&renesas_eth_sw_pm_ops),
 		.of_match_table = renesas_eth_sw_of_table,
 	}
 };