tlan: proper shared IRQ support
Stephen Hemminger [Fri, 30 May 2008 16:49:57 +0000 (09:49 -0700)]
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>

drivers/net/tlan.c

index afc8310..01aa331 100644 (file)
@@ -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 */
-
-
 
 
        /***************************************************************