ALSA: hda - Allow to pass position_fix=0 explicitly

Set the default value of position_fix -1, and allow user passing
position_fix=0 explicitly to set the "auto" position-fix mode.
Otherwise the auto mode may be switched to others like COMBO of
VIACOMBO when the controller prefers it, thus user can't set the auto
mode any longer.

Also updated the documentation appropriately, too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 3 insertions, 2 deletions

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index e1a12c754de9..195d84726187 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -64,7 +64,7 @@ static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
 static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;
 static char *model[SNDRV_CARDS];
-static int position_fix[SNDRV_CARDS];
+static int position_fix[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = -1};
 static int bdl_pos_adj[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = -1};
 static int probe_mask[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = -1};
 static int probe_only[SNDRV_CARDS];
@@ -88,7 +88,7 @@ module_param_array(model, charp, NULL, 0444);
 MODULE_PARM_DESC(model, "Use the given board model.");
 module_param_array(position_fix, int, NULL, 0444);
 MODULE_PARM_DESC(position_fix, "DMA pointer read method."
-                 "(0 = auto, 1 = LPIB, 2 = POSBUF, 3 = VIACOMBO, 4 = COMBO).");
+                 "(-1 = system default, 0 = auto, 1 = LPIB, 2 = POSBUF, 3 = VIACOMBO, 4 = COMBO).");
 module_param_array(bdl_pos_adj, int, NULL, 0644);
 MODULE_PARM_DESC(bdl_pos_adj, "BDL position adjustment offset.");
 module_param_array(probe_mask, int, NULL, 0444);
@@ -2813,6 +2813,7 @@ static int __devinit check_position_fix(struct azx *chip, int fix)
         const struct snd_pci_quirk *q;
 
         switch (fix) {
+        case POS_FIX_AUTO:
         case POS_FIX_LPIB:
         case POS_FIX_POSBUF:
         case POS_FIX_VIACOMBO: