sky2: irqname based on pci address

This is based on Michal Schmidt fix for skge.

Most network drivers request their IRQ when the interface is activated.
sky2 does it in ->probe() instead, because it can work with two-port
cards where the two net_devices use the same IRQ. This works fine most
of the time, except in some situations when the interface gets renamed.
Consider this example:

1. modprobe sky2
   The card is detected as eth0 and requests IRQ 17. Directory
   /proc/irq/17/eth0 is created.
2. There is an udev rule which says this interface should be called
   eth1, so udev renames eth0 -> eth1.
3. modprobe 8139too
   The Realtek card is detected as eth0. It will be using IRQ 17 too.
4. ip link set eth0 up
   Now 8139too requests IRQ 17.

The result is:
WARNING: at fs/proc/generic.c:590 proc_register ...
proc_dir_entry '17/eth0' already registered

The fix is for sky2 to name the irq based on the pci device, as is done
by some other devices DRM, infiniband, ...  ie. sky2@pci:0000:00:00

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Reviewed-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 7 insertions, 2 deletions

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index ef1165718dd7..2ab5c39f33ca 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -4487,13 +4487,16 @@ static int __devinit sky2_probe(struct pci_dev *pdev,
         wol_default = device_may_wakeup(&pdev->dev) ? WAKE_MAGIC : 0;
 
         err = -ENOMEM;
-        hw = kzalloc(sizeof(*hw), GFP_KERNEL);
+
+        hw = kzalloc(sizeof(*hw) + strlen(DRV_NAME "@pci:")
+                     + strlen(pci_name(pdev)) + 1, GFP_KERNEL);
         if (!hw) {
                 dev_err(&pdev->dev, "cannot allocate hardware struct\n");
                 goto err_out_free_regions;
         }
 
         hw->pdev = pdev;
+        sprintf(hw->irq_name, DRV_NAME "@pci:%s", pci_name(pdev));
 
         hw->regs = ioremap_nocache(pci_resource_start(pdev, 0), 0x4000);
         if (!hw->regs) {
@@ -4539,7 +4542,7 @@ static int __devinit sky2_probe(struct pci_dev *pdev,
 
         err = request_irq(pdev->irq, sky2_intr,
                           (hw->flags & SKY2_HW_USE_MSI) ? 0 : IRQF_SHARED,
-                          dev->name, hw);
+                          hw->irq_name, hw);
         if (err) {
                 dev_err(&pdev->dev, "cannot assign irq %d\n", pdev->irq);
                 goto err_out_unregister;
diff --git a/drivers/net/sky2.h b/drivers/net/sky2.h
index e0f23a101043..ed54129698b4 100644
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -2085,6 +2085,8 @@ struct sky2_hw {
         struct timer_list    watchdog_timer;
         struct work_struct   restart_work;
         wait_queue_head_t    msi_wait;
+
+        char                 irq_name[0];
 };
 
 static inline int sky2_is_copper(const struct sky2_hw *hw)