1 files changed, 93 insertions, 18 deletions

diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 76e3800765f8..adb5325f4934 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -22,6 +22,7 @@
 #include <linux/of_platform.h>
 #include <linux/of_net.h>
 #include <linux/sysfs.h>
+#include <linux/phy_fixed.h>
 #include "dsa_priv.h"
 
 char dsa_driver_version[] = "0.1";
@@ -305,7 +306,7 @@ static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
         if (ret < 0)
                 goto out;
 
-        ds->slave_mii_bus = mdiobus_alloc();
+        ds->slave_mii_bus = devm_mdiobus_alloc(parent);
         if (ds->slave_mii_bus == NULL) {
                 ret = -ENOMEM;
                 goto out;
@@ -314,7 +315,7 @@ static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
 
         ret = mdiobus_register(ds->slave_mii_bus);
         if (ret < 0)
-                goto out_free;
+                goto out;
 
 
         /*
@@ -367,10 +368,7 @@ static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
 
         return ret;
 
-out_free:
-        mdiobus_free(ds->slave_mii_bus);
 out:
-        kfree(ds);
         return ret;
 }
 
@@ -400,7 +398,7 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index,
         /*
          * Allocate and initialise switch state.
          */
-        ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
+        ds = devm_kzalloc(parent, sizeof(*ds) + drv->priv_size, GFP_KERNEL);
         if (ds == NULL)
                 return ERR_PTR(-ENOMEM);
 
@@ -420,10 +418,47 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index,
 
 static void dsa_switch_destroy(struct dsa_switch *ds)
 {
+        struct device_node *port_dn;
+        struct phy_device *phydev;
+        struct dsa_chip_data *cd = ds->pd;
+        int port;
+
 #ifdef CONFIG_NET_DSA_HWMON
         if (ds->hwmon_dev)
                 hwmon_device_unregister(ds->hwmon_dev);
 #endif
+
+        /* Disable configuration of the CPU and DSA ports */
+        for (port = 0; port < DSA_MAX_PORTS; port++) {
+                if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
+                        continue;
+
+                port_dn = cd->port_dn[port];
+                if (of_phy_is_fixed_link(port_dn)) {
+                        phydev = of_phy_find_device(port_dn);
+                        if (phydev) {
+                                int addr = phydev->addr;
+
+                                phy_device_free(phydev);
+                                of_node_put(port_dn);
+                                fixed_phy_del(addr);
+                        }
+                }
+        }
+
+        /* Destroy network devices for physical switch ports. */
+        for (port = 0; port < DSA_MAX_PORTS; port++) {
+                if (!(ds->phys_port_mask & (1 << port)))
+                        continue;
+
+                if (!ds->ports[port])
+                        continue;
+
+                unregister_netdev(ds->ports[port]);
+                free_netdev(ds->ports[port]);
+        }
+
+        mdiobus_unregister(ds->slave_mii_bus);
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -634,6 +669,10 @@ static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
                         port_index++;
                 }
                 kfree(pd->chip[i].rtable);
+
+                /* Drop our reference to the MDIO bus device */
+                if (pd->chip[i].host_dev)
+                        put_device(pd->chip[i].host_dev);
         }
         kfree(pd->chip);
 }
@@ -661,16 +700,22 @@ static int dsa_of_probe(struct device *dev)
                 return -EPROBE_DEFER;
 
         ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
-        if (!ethernet)
-                return -EINVAL;
+        if (!ethernet) {
+                ret = -EINVAL;
+                goto out_put_mdio;
+        }
 
         ethernet_dev = of_find_net_device_by_node(ethernet);
-        if (!ethernet_dev)
-                return -EPROBE_DEFER;
+        if (!ethernet_dev) {
+                ret = -EPROBE_DEFER;
+                goto out_put_mdio;
+        }
 
         pd = kzalloc(sizeof(*pd), GFP_KERNEL);
-        if (!pd)
-                return -ENOMEM;
+        if (!pd) {
+                ret = -ENOMEM;
+                goto out_put_ethernet;
+        }
 
         dev->platform_data = pd;
         pd->of_netdev = ethernet_dev;
@@ -691,7 +736,9 @@ static int dsa_of_probe(struct device *dev)
                 cd = &pd->chip[chip_index];
 
                 cd->of_node = child;
-                cd->host_dev = &mdio_bus->dev;
+
+                /* When assigning the host device, increment its refcount */
+                cd->host_dev = get_device(&mdio_bus->dev);
 
                 sw_addr = of_get_property(child, "reg", NULL);
                 if (!sw_addr)
@@ -711,6 +758,12 @@ static int dsa_of_probe(struct device *dev)
                                 ret = -EPROBE_DEFER;
                                 goto out_free_chip;
                         }
+
+                        /* Drop the mdio_bus device ref, replacing the host
+                         * device with the mdio_bus_switch device, keeping
+                         * the refcount from of_mdio_find_bus() above.
+                         */
+                        put_device(cd->host_dev);
                         cd->host_dev = &mdio_bus_switch->dev;
                 }
 
@@ -744,6 +797,10 @@ static int dsa_of_probe(struct device *dev)
                 }
         }
 
+        /* The individual chips hold their own refcount on the mdio bus,
+         * so drop ours */
+        put_device(&mdio_bus->dev);
+
         return 0;
 
 out_free_chip:
@@ -751,6 +808,10 @@ out_free_chip:
 out_free:
         kfree(pd);
         dev->platform_data = NULL;
+out_put_ethernet:
+        put_device(&ethernet_dev->dev);
+out_put_mdio:
+        put_device(&mdio_bus->dev);
         return ret;
 }
 
@@ -762,6 +823,7 @@ static void dsa_of_remove(struct device *dev)
                 return;
 
         dsa_of_free_platform_data(pd);
+        put_device(&pd->of_netdev->dev);
         kfree(pd);
 }
 #else
@@ -775,10 +837,11 @@ static inline void dsa_of_remove(struct device *dev)
 }
 #endif
 
-static void dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
-                          struct device *parent, struct dsa_platform_data *pd)
+static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
+                         struct device *parent, struct dsa_platform_data *pd)
 {
         int i;
+        unsigned configured = 0;
 
         dst->pd = pd;
         dst->master_netdev = dev;
@@ -798,9 +861,17 @@ static void dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
                 dst->ds[i] = ds;
                 if (ds->drv->poll_link != NULL)
                         dst->link_poll_needed = 1;
+
+                ++configured;
         }
 
         /*
+         * If no switch was found, exit cleanly
+         */
+        if (!configured)
+                return -EPROBE_DEFER;
+
+        /*
          * If we use a tagging format that doesn't have an ethertype
          * field, make sure that all packets from this point on get
          * sent to the tag format's receive function.
@@ -816,6 +887,8 @@ static void dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
                 dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
                 add_timer(&dst->link_poll_timer);
         }
+
+        return 0;
 }
 
 static int dsa_probe(struct platform_device *pdev)
@@ -856,7 +929,7 @@ static int dsa_probe(struct platform_device *pdev)
                 goto out;
         }
 
-        dst = kzalloc(sizeof(*dst), GFP_KERNEL);
+        dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
         if (dst == NULL) {
                 dev_put(dev);
                 ret = -ENOMEM;
@@ -865,7 +938,9 @@ static int dsa_probe(struct platform_device *pdev)
 
         platform_set_drvdata(pdev, dst);
 
-        dsa_setup_dst(dst, dev, &pdev->dev, pd);
+        ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
+        if (ret)
+                goto out;
 
         return 0;
 
@@ -887,7 +962,7 @@ static void dsa_remove_dst(struct dsa_switch_tree *dst)
         for (i = 0; i < dst->pd->nr_chips; i++) {
                 struct dsa_switch *ds = dst->ds[i];
 
-                if (ds != NULL)
+                if (ds)
                         dsa_switch_destroy(ds);
         }
 }