[PATCH] ppc32: Fix IDE related crash on wakeup

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

Hi !

I noticed an occasional crash on wakeup from sleep on my powerbook
(strangly never happened before, probably timing related) that appears
to be due to a dangling interrupt while the chip is put to sleep and
beeing reset on wakeup.

This patch fixes is by disabling the irq in the ide pmac driver while
asleep and only re-enable it after the chip has been fully reset. This
is safe to do so as the interrupt of these apple IDE cells is never
shared.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Index: linux-work/drivers/ide/ppc/pmac.c
===================================================================
--- linux-work.orig/drivers/ide/ppc/pmac.c	2005-04-13 10:53:39.000000000 +1000
+++ linux-work/drivers/ide/ppc/pmac.c	2005-04-13 14:17:41.000000000 +1000
@@ -1204,6 +1204,8 @@
 	}
 #endif /* CONFIG_BLK_DEV_IDE_PMAC_BLINK */
 
+	disable_irq(pmif->irq);
+
 	/* The media bay will handle itself just fine */
 	if (pmif->mediabay)
 		return 0;
@@ -1236,7 +1238,6 @@
 		ppc_md.feature_call(PMAC_FTR_IDE_ENABLE, pmif->node, pmif->aapl_bus_id, 1);
 		msleep(10);
 		ppc_md.feature_call(PMAC_FTR_IDE_RESET, pmif->node, pmif->aapl_bus_id, 0);
-		msleep(jiffies_to_msecs(IDE_WAKEUP_DELAY));
 
 		/* Kauai has it different */
 		if (pmif->kauai_fcr) {
@@ -1244,11 +1245,15 @@
 			fcr |= KAUAI_FCR_UATA_RESET_N | KAUAI_FCR_UATA_ENABLE;
 			writel(fcr, pmif->kauai_fcr);
 		}
+
+		msleep(jiffies_to_msecs(IDE_WAKEUP_DELAY));
 	}
 
 	/* Sanitize drive timings */
 	sanitize_timings(pmif);
 
+	enable_irq(pmif->irq);
+
 	return 0;
 }