tlan: proper shared IRQ support

Handle shared IRQ correctly. If IRQ is shared, it typically will show up
as an IRQ with an empty status field. So check in driver and handle it
without crapping out with invalid interrupt message.

Compile tested only.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 17 insertions, 44 deletions

diff --git a/drivers/net/tlan.c b/drivers/net/tlan.c
index afc831002db2..01aa331e1838 100644
--- a/drivers/net/tlan.c
+++ b/drivers/net/tlan.c
@@ -218,7 +218,7 @@ static	int		bbuf;
 module_param(bbuf, int, 0);
 MODULE_PARM_DESC(bbuf, "ThunderLAN use big buffer (0-1)");
 
-static  char            TLanSignature[] = "TLAN";
+static  const char TLanSignature[] = "TLAN";
 static  const char tlan_banner[] = "ThunderLAN driver v1.15\n";
 static  int tlan_have_pci;
 static  int tlan_have_eisa;
@@ -297,7 +297,6 @@ static void	TLan_tx_timeout( struct net_device *dev);
 static void     TLan_tx_timeout_work(struct work_struct *work);
 static int      tlan_init_one( struct pci_dev *pdev, const struct pci_device_id *ent);
 
-static u32      TLan_HandleInvalid( struct net_device *, u16 );
 static u32      TLan_HandleTxEOF( struct net_device *, u16 );
 static u32      TLan_HandleStatOverflow( struct net_device *, u16 );
 static u32      TLan_HandleRxEOF( struct net_device *, u16 );
@@ -366,7 +365,7 @@ TLan_GetSKB( const struct tlan_list_tag *tag)
 
 
 static TLanIntVectorFunc *TLanIntVector[TLAN_INT_NUMBER_OF_INTS] = {
-        TLan_HandleInvalid,
+        NULL,
         TLan_HandleTxEOF,
         TLan_HandleStatOverflow,
         TLan_HandleRxEOF,
@@ -935,7 +934,8 @@ static int TLan_Open( struct net_device *dev )
         int             err;
 
         priv->tlanRev = TLan_DioRead8( dev->base_addr, TLAN_DEF_REVISION );
-        err = request_irq( dev->irq, TLan_HandleInterrupt, IRQF_SHARED, TLanSignature, dev );
+        err = request_irq( dev->irq, TLan_HandleInterrupt, IRQF_SHARED,
+                           dev->name, dev );
 
         if ( err ) {
                 printk(KERN_ERR "TLAN:  Cannot open %s because IRQ %d is already in use.\n", dev->name, dev->irq );
@@ -1167,33 +1167,31 @@ static int TLan_StartTx( struct sk_buff *skb, struct net_device *dev )
 
 static irqreturn_t TLan_HandleInterrupt(int irq, void *dev_id)
 {
-        u32             ack;
-        struct net_device       *dev;
-        u32             host_cmd;
+        struct net_device       *dev = dev_id;
+        TLanPrivateInfo *priv = netdev_priv(dev);
         u16             host_int;
-        int             type;
-        TLanPrivateInfo *priv;
-
-        dev = dev_id;
-        priv = netdev_priv(dev);
+        u16             type;
 
         spin_lock(&priv->lock);
 
         host_int = inw( dev->base_addr + TLAN_HOST_INT );
-        outw( host_int, dev->base_addr + TLAN_HOST_INT );
-
         type = ( host_int & TLAN_HI_IT_MASK ) >> 2;
+        if ( type ) {
+                u32     ack;
+                u32     host_cmd;
 
-        ack = TLanIntVector[type]( dev, host_int );
+                outw( host_int, dev->base_addr + TLAN_HOST_INT );
+                ack = TLanIntVector[type]( dev, host_int );
 
-        if ( ack ) {
-                host_cmd = TLAN_HC_ACK | ack | ( type << 18 );
-                outl( host_cmd, dev->base_addr + TLAN_HOST_CMD );
+                if ( ack ) {
+                        host_cmd = TLAN_HC_ACK | ack | ( type << 18 );
+                        outl( host_cmd, dev->base_addr + TLAN_HOST_CMD );
+                }
         }
 
         spin_unlock(&priv->lock);
 
-        return IRQ_HANDLED;
+        return IRQ_RETVAL(type);
 } /* TLan_HandleInterrupts */
 
 
@@ -1359,31 +1357,6 @@ static void TLan_SetMulticastList( struct net_device *dev )
 *****************************************************************************/
 
 
-        /***************************************************************
-         *      TLan_HandleInvalid
-         *
-         *      Returns:
-         *              0
-         *      Parms:
-         *              dev             Device assigned the IRQ that was
-         *                              raised.
-         *              host_int        The contents of the HOST_INT
-         *                              port.
-         *
-         *      This function handles invalid interrupts.  This should
-         *      never happen unless some other adapter is trying to use
-         *      the IRQ line assigned to the device.
-         *
-         **************************************************************/
-
-static u32 TLan_HandleInvalid( struct net_device *dev, u16 host_int )
-{
-        /* printk( "TLAN:  Invalid interrupt on %s.\n", dev->name ); */
-        return 0;
-
-} /* TLan_HandleInvalid */
-
-
 
 
         /***************************************************************