From: Takashi Iwai <tiwai@suse.de>
Date: Fri, 12 Jun 2015 05:53:58 +0000 (+0200)
Subject: ALSA: hda - Abort the probe without i915 binding for HSW/BDW
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=535115b5ff51c702a9a22feb918707c2fe1fbd17;p=openwrt%2Fstaging%2Fblogic.git

ALSA: hda - Abort the probe without i915 binding for HSW/BDW

The previous patch tried to continue the probe if i915 binding fails.
For for simplicity reason, we haven't implemented abort even for
controller chips that are dedicated for HDMI/DP on HSW and BDW.
However, Mengdong suggested that this can be dangerous; BIOS may
disable gfx power well although the PCI entry for HD-audio is left,
and this may result in the unexpected behavior, kernel errors, etc.

For avoiding this situation, abort the probe at i915 binding failure
only for HSW/BDW chips selectively.  For other chips, it still
continues.

Fixes: bf06848bdbe5 ('ALSA: hda - Continue probing even if i915 binding fails')
Reported-by: Mengdong Lin <mengdong.lin@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 8a0af6770e1d..a244ba706317 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -340,6 +340,11 @@ enum {
 #define use_vga_switcheroo(chip)	0
 #endif
 
+#define CONTROLLER_IN_GPU(pci) (((pci)->device == 0x0a0c) || \
+					((pci)->device == 0x0c0c) || \
+					((pci)->device == 0x0d0c) || \
+					((pci)->device == 0x160c))
+
 static char *driver_short_names[] = {
 	[AZX_DRIVER_ICH] = "HDA Intel",
 	[AZX_DRIVER_PCH] = "HDA Intel PCH",
@@ -1854,8 +1859,17 @@ static int azx_probe_continue(struct azx *chip)
 	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
 #ifdef CONFIG_SND_HDA_I915
 		err = hda_i915_init(hda);
-		if (err < 0)
-			goto skip_i915;
+		if (err < 0) {
+			/* if the controller is bound only with HDMI/DP
+			 * (for HSW and BDW), we need to abort the probe;
+			 * for other chips, still continue probing as other
+			 * codecs can be on the same link.
+			 */
+			if (CONTROLLER_IN_GPU(pci))
+				goto out_free;
+			else
+				goto skip_i915;
+		}
 		err = hda_display_power(hda, true);
 		if (err < 0) {
 			dev_err(chip->card->dev,