[PATCH] Char: isicom, check card state in isr

Check if the card really interrupted us by reading its IO space and eventualy
return IRQ_NONE.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/char/isicom.c

@@ -540,6 +540,11 @@ static irqreturn_t isicom_interrupt(int irq, void *dev_id)
 		return IRQ_NONE;
 
 	base = card->base;
+
+	/* did the card interrupt us? */
+	if (!(inw(base + 0x0e) & 0x02))
+		return IRQ_NONE;
+
 	spin_lock(&card->card_lock);
 
 	/*