net: dsa: utilize of_find_net_device_by_node

Using of_find_device_by_node() restricts the search to platform_device that
match the specified device_node pointer. This is not even remotely true for
network devices backed by a pci_device for instance.

of_find_net_device_by_node() allows us to do a more thorough lookup to find the
struct net_device corresponding to a particular device_node pointer.

For symetry with the non-OF code path, we hold the net_device pointer in
dsa_probe() just like what dev_to_net_dev() does when we call this
function.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 12 insertions, 5 deletions

diff --git a/include/net/dsa.h b/include/net/dsa.h
index b525ac516559..47917e5e1e12 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -72,6 +72,7 @@ struct dsa_platform_data {
          * to the root switch chip of the tree.
          */
         struct device   *netdev;
+        struct net_device *of_netdev;
 
         /*
          * Info structs describing each of the switch chips
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index b40f11bb419c..899772108ee3 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -20,6 +20,7 @@
 #include <linux/of.h>
 #include <linux/of_mdio.h>
 #include <linux/of_platform.h>
+#include <linux/of_net.h>
 #include <linux/sysfs.h>
 #include "dsa_priv.h"
 
@@ -583,7 +584,7 @@ static int dsa_of_probe(struct device *dev)
         struct device_node *np = dev->of_node;
         struct device_node *child, *mdio, *ethernet, *port, *link;
         struct mii_bus *mdio_bus;
-        struct platform_device *ethernet_dev;
+        struct net_device *ethernet_dev;
         struct dsa_platform_data *pd;
         struct dsa_chip_data *cd;
         const char *port_name;
@@ -604,7 +605,7 @@ static int dsa_of_probe(struct device *dev)
         if (!ethernet)
                 return -EINVAL;
 
-        ethernet_dev = of_find_device_by_node(ethernet);
+        ethernet_dev = of_find_net_device_by_node(ethernet);
         if (!ethernet_dev)
                 return -EPROBE_DEFER;
 
@@ -613,7 +614,7 @@ static int dsa_of_probe(struct device *dev)
                 return -ENOMEM;
 
         dev->platform_data = pd;
-        pd->netdev = &ethernet_dev->dev;
+        pd->of_netdev = ethernet_dev;
         pd->nr_chips = of_get_available_child_count(np);
         if (pd->nr_chips > DSA_MAX_SWITCHES)
                 pd->nr_chips = DSA_MAX_SWITCHES;
@@ -771,10 +772,15 @@ static int dsa_probe(struct platform_device *pdev)
                 pd = pdev->dev.platform_data;
         }
 
-        if (pd == NULL || pd->netdev == NULL)
+        if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
                 return -EINVAL;
 
-        dev = dev_to_net_device(pd->netdev);
+        if (pd->of_netdev) {
+                dev = pd->of_netdev;
+                dev_hold(dev);
+        } else {
+                dev = dev_to_net_device(pd->netdev);
+        }
         if (dev == NULL) {
                 ret = -EPROBE_DEFER;
                 goto out;