From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 26 Apr 2011 13:25:02 +0000 (+0200)
Subject: ALSA: hda - Enable sync_write workaround for AMD generically
X-Git-Url: http://git.alex.org.uk

ALSA: hda - Enable sync_write workaround for AMD generically

BugLink: http://bugs.launchpad.net/bugs/741825

Backport from d507cd668a3f6d07b31e914722b453c454b03204.

The workaround for AMD chipset via sync_write flag seems needed for
machines with Realtek codecs.  So, it's better to activate it
generically in hda_intel.c from the beginning.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
---

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 5fd012b..c9fb18e 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -1449,6 +1449,17 @@ static int __devinit azx_codec_create(struct azx *chip, const char *model)
 		}
 	}
 
+	/* AMD chipsets often cause the communication stalls upon certain
+	 * sequence like the pin-detection.  It seems that forcing the synced
+	 * access works around the stall.  Grrr...
+	 */
+	if (chip->pci->vendor == PCI_VENDOR_ID_AMD ||
+	    chip->pci->vendor == PCI_VENDOR_ID_ATI) {
+		snd_printk(KERN_INFO SFX "Enable sync_write for AMD chipset\n");
+		chip->bus->sync_write = 1;
+		chip->bus->allow_bus_reset = 1;
+	}
+
 	/* Then create codec instances */
 	for (c = 0; c < max_slots; c++) {
 		if ((chip->codec_mask & (1 << c)) & chip->codec_probe_mask) {