[PATCH net-next v4 02/15] net: ethernet: cortina: Keep PHY-less port bound for shared IRQ

@@ -25,6 +25,7 @@
 #include <linux/interrupt.h>
 #include <linux/reset.h>
 #include <linux/clk.h>
+#include <linux/rtnetlink.h>
 #include <linux/of.h>
 #include <linux/of_mdio.h>
 #include <linux/of_net.h>

@@ -155,6 +156,7 @@ struct gemini_ethernet_port {
 struct gemini_ethernet {
 	struct device *dev;
 	void __iomem *base;
+	/* Protected by RTNL. */
 	struct gemini_ethernet_port *port0;
 	struct gemini_ethernet_port *port1;
 	bool initialized;

@@ -1051,10 +1053,17 @@ static int geth_resize_freeq(struct gemini_ethernet_port *port)
 	u32 en;
 	int ret;
 
+	ASSERT_RTNL();
+
+	/* The software free queue interrupt is routed through port 1. */
+	if (!geth->initialized || !geth->port0 || !geth->port1)
+		return -ENODEV;
+
 	if (netdev->dev_id == 0)
-		other_netdev = geth->port1->netdev;
+		other_port = geth->port1;
 	else
-		other_netdev = geth->port0->netdev;
+		other_port = geth->port0;
+	other_netdev = other_port ? other_port->netdev : NULL;
 
 	if (other_netdev && netif_running(other_netdev))
 		return -EBUSY;

@@ -1065,7 +1074,6 @@ static int geth_resize_freeq(struct gemini_ethernet_port *port)
 		   new_size,
 		   port->rxq_order);
 	if (other_netdev) {
-		other_port = netdev_priv(other_netdev);
 		new_size += 1 << (other_port->rxq_order + 1);
 		netdev_dbg(other_netdev, "port %d size: %d order %d\n",
 			   other_netdev->dev_id,

@@ -2387,8 +2395,28 @@ static irqreturn_t gemini_port_irq(int irq, void *data)
 	return ret;
 }
 
+static void gemini_port_clear(struct gemini_ethernet_port *port)
+{
+	struct gemini_ethernet *geth = port->geth;
+
+	ASSERT_RTNL();
+
+	if (!port->id && geth->port0 == port)
+		geth->port0 = NULL;
+	else if (port->id && geth->port1 == port)
+		geth->port1 = NULL;
+	else
+		return;
+
+	geth->initialized = false;
+}
+
 static void gemini_port_remove(struct gemini_ethernet_port *port)
 {
+	rtnl_lock();
+	gemini_port_clear(port);
+	rtnl_unlock();
+
 	if (port->netdev) {
 		unregister_netdev(port->netdev);
 		phy_disconnect(port->netdev->phydev);

@@ -2398,12 +2426,12 @@ static void gemini_port_remove(struct gemini_ethernet_port *port)
 
 static void gemini_ethernet_init(struct gemini_ethernet *geth)
 {
+	ASSERT_RTNL();
+
 	/* Only do this once both ports are online */
 	if (geth->initialized)
 		return;
-	if (geth->port0 && geth->port1)
-		geth->initialized = true;
-	else
+	if (!geth->port0 || !geth->port1)
 		return;
 
 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_0_REG);

@@ -2446,6 +2474,20 @@ static void gemini_ethernet_init(struct gemini_ethernet *geth)
 	 * set up and enable the queue IRQ. FIXME: fragile.
 	 */
 	geth->freeq_order = 1;
+	geth->initialized = true;
+}
+
+static void gemini_port_publish(struct gemini_ethernet_port *port)
+{
+	struct gemini_ethernet *geth = port->geth;
+
+	ASSERT_RTNL();
+
+	if (!port->id)
+		geth->port0 = port;
+	else
+		geth->port1 = port;
+	gemini_ethernet_init(geth);
 }
 
 static void gemini_port_save_mac_addr(struct gemini_ethernet_port *port)

@@ -2541,15 +2583,6 @@ static int gemini_ethernet_port_probe(struct platform_device *pdev)
 	reset_control_reset(port->reset);
 	usleep_range(100, 500);
 
-	/* Assign pointer in the main state container */
-	if (!id)
-		geth->port0 = port;
-	else
-		geth->port1 = port;
-
-	/* This will just be done once both ports are up and reset */
-	gemini_ethernet_init(geth);
-
 	platform_set_drvdata(pdev, port);
 
 	/* Set up and register the netdev */

@@ -2600,6 +2633,16 @@ static int gemini_ethernet_port_probe(struct platform_device *pdev)
 	if (ret)
 		goto unprepare;
 
+	if (!of_property_present(np, "phy-handle") &&
+	    !of_phy_is_fixed_link(np)) {
+		dev_info(dev, "no PHY, keeping port for shared IRQ\n");
+		port->netdev = NULL;
+		rtnl_lock();
+		gemini_port_publish(port);
+		rtnl_unlock();
+		return 0;
+	}
+
 	ret = gmac_setup_phy(netdev);
 	if (ret) {
 		netdev_err(netdev,

@@ -2607,9 +2650,15 @@ static int gemini_ethernet_port_probe(struct platform_device *pdev)
 		goto unprepare;
 	}
 
-	ret = register_netdev(netdev);
-	if (ret)
+	rtnl_lock();
+	ret = register_netdevice(netdev);
+	if (!ret)
+		gemini_port_publish(port);
+	rtnl_unlock();
+	if (ret) {
+		phy_disconnect(netdev->phydev);
 		goto unprepare;
+	}
 
 	return 0;
 

@@ -2686,10 +2735,13 @@ static void gemini_ethernet_remove(struct platform_device *pdev)
 {
 	struct gemini_ethernet *geth = platform_get_drvdata(pdev);
 
+	rtnl_lock();
+	geth->initialized = false;
+	rtnl_unlock();
+
 	devm_of_platform_depopulate(&pdev->dev);
 	writel(0, geth->base + GLOBAL_INTERRUPT_ENABLE_4_REG);
 	geth_cleanup_freeq(geth);
-	geth->initialized = false;
 }
 
 static const struct of_device_id gemini_ethernet_of_match[] = {