[PATCH] ALSA: Fix Oops of suspend/resume with generic drivers

The patch fixes Oops from sound drivers using generic platform device
but have no suspend/resume callbacks.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

sound/core/init.c

@@ -828,7 +828,8 @@ static int snd_generic_suspend(struct device *dev, pm_message_t state, u32 level
 	card = get_snd_generic_card(dev);
 	if (card->power_state == SNDRV_CTL_POWER_D3hot)
 		return 0;
-	card->pm_suspend(card, PMSG_SUSPEND);
+	if (card->pm_suspend)
+		card->pm_suspend(card, PMSG_SUSPEND);
 	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 	return 0;
 }
@@ -843,7 +844,8 @@ static int snd_generic_resume(struct device *dev, u32 level)
 	card = get_snd_generic_card(dev);
 	if (card->power_state == SNDRV_CTL_POWER_D0)
 		return 0;
-	card->pm_resume(card);
+	if (card->pm_suspend)
+		card->pm_resume(card);
 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
 	return 0;
 }