ALSA: aaci - Fix alignment faults on ARM Cortex introduced by commit 2…

…9a4f2d The commit 29a4f2d used writel() at offset 0x26 which is half-word aligned causing unaligned exceptions on a Cortex-A8. The original patch solved the "aaci-pl041 fpga:04: ac97 read back fail" issue on a soft reset. Reading from any arbitrary aaci register seems to solve this issue. Signed-off-by: Philby John <[email protected]> Acked-by: Russell King <[email protected]> Signed-off-by: Takashi Iwai <[email protected]>
chewitt · Apr 13, 2010 · b68b58f · b68b58f
1 parent 29aac00
commit b68b58f
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/sound/arm/aaci.c b/sound/arm/aaci.c
@@ -863,7 +863,6 @@ static int __devinit aaci_probe_ac97(struct aaci *aaci)
 	struct snd_ac97 *ac97;
 	int ret;
 
-	writel(0, aaci->base + AC97_POWERDOWN);
 	/*
 	 * Assert AACIRESET for 2us
 	 */
@@ -1047,7 +1046,11 @@ static int __devinit aaci_probe(struct amba_device *dev, struct amba_id *id)
 
 	writel(0x1fff, aaci->base + AACI_INTCLR);
 	writel(aaci->maincr, aaci->base + AACI_MAINCR);
-
+	/*
+	 * Fix: ac97 read back fail errors by reading
+	 * from any arbitrary aaci register.
+	 */
+	readl(aaci->base + AACI_CSCH1);
 	ret = aaci_probe_ac97(aaci);
 	if (ret)
 		goto out;