[3.16-stable,50/87] net: am2150: fix nmclan_cs.c shared interrupt handling

Message ID 20170505194745.3627137-51-arnd@arndb.de
State New
Headers show
  • build warnings and errors
Related show

Commit Message

Arnd Bergmann May 5, 2017, 7:47 p.m.
Commit ec48c4ad83d711f18daea527bb2c78d388cc5ef3 upstream.

A recent patch tried to work around a valid warning for the use of a
deprecated interface by blindly changing from the old
pcmcia_request_exclusive_irq() interface to pcmcia_request_irq().

This driver has an interrupt handler that is not currently aware
of shared interrupts, but can be easily converted to be.
At the moment, the driver reads the interrupt status register
repeatedly until it contains only zeroes in the interesting bits,
and handles each bit individually.

This patch adds the missing part of returning IRQ_NONE in case none
of the bits are set to start with, so we can move on to the next
interrupt source.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Fixes: 5f5316fcd08ef7 ("am2150: Update nmclan_cs.c to use update PCMCIA API")
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

 drivers/net/ethernet/amd/nmclan_cs.c | 2 ++
 1 file changed, 2 insertions(+)



diff --git a/drivers/net/ethernet/amd/nmclan_cs.c b/drivers/net/ethernet/amd/nmclan_cs.c
index abf3b1581c82..11cb05df749c 100644
--- a/drivers/net/ethernet/amd/nmclan_cs.c
+++ b/drivers/net/ethernet/amd/nmclan_cs.c
@@ -952,6 +952,8 @@  static irqreturn_t mace_interrupt(int irq, void *dev_id)
   do {
     /* WARNING: MACE_IR is a READ/CLEAR port! */
     status = inb(ioaddr + AM2150_MACE_BASE + MACE_IR);
+    if (!(status & ~MACE_IMR_DEFAULT) && IntrCnt == MACE_MAX_IR_ITERATIONS)
+      return IRQ_NONE;
     pr_debug("mace_interrupt: irq 0x%X status 0x%X.\n", irq, status);