[ALSA] hda-intel - Auto-correction of the DMA position mode

Modules: HDA Intel driver

Switch the method to measure the current DMA position automatically
from position-buffer mode to LPIB-read mode with a sanity check.
Some hardwares seems to have problem with the position buffer.

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

1 files changed, 15 insertions, 7 deletions

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 016fbc263e55..c096606970ff 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -250,7 +250,6 @@ struct azx_dev {
         unsigned int fragsize;          /* size of each period in bytes */
         unsigned int frags;             /* number for period in the play buffer */
         unsigned int fifo_size;         /* FIFO size */
-        unsigned int last_pos;          /* last updated period position */
 
         void __iomem *sd_addr;          /* stream descriptor pointer */
 
@@ -261,10 +260,11 @@ struct azx_dev {
         unsigned int format_val;        /* format value to be set in the controller and the codec */
         unsigned char stream_tag;       /* assigned stream */
         unsigned char index;            /* stream index */
+        /* for sanity check of position buffer */
+        unsigned int period_intr;
 
         unsigned int opened: 1;
         unsigned int running: 1;
-        unsigned int period_updating: 1;
 };
 
 /* CORB/RIRB */
@@ -804,11 +804,10 @@ static irqreturn_t azx_interrupt(int irq, void* dev_id, struct pt_regs *regs)
                 if (status & azx_dev->sd_int_sta_mask) {
                         azx_sd_writeb(azx_dev, SD_STS, SD_INT_MASK);
                         if (azx_dev->substream && azx_dev->running) {
-                                azx_dev->period_updating = 1;
+                                azx_dev->period_intr++;
                                 spin_unlock(&chip->reg_lock);
                                 snd_pcm_period_elapsed(azx_dev->substream);
                                 spin_lock(&chip->reg_lock);
-                                azx_dev->period_updating = 0;
                         }
                 }
         }
@@ -1119,7 +1118,6 @@ static int azx_pcm_prepare(struct snd_pcm_substream *substream)
                 azx_dev->fifo_size = azx_sd_readw(azx_dev, SD_FIFOSIZE) + 1;
         else
                 azx_dev->fifo_size = 0;
-        azx_dev->last_pos = 0;
 
         return hinfo->ops.prepare(hinfo, apcm->codec, azx_dev->stream_tag,
                                   azx_dev->format_val, substream);
@@ -1167,10 +1165,20 @@ static snd_pcm_uframes_t azx_pcm_pointer(struct snd_pcm_substream *substream)
         struct azx_dev *azx_dev = get_azx_dev(substream);
         unsigned int pos;
 
-        if (chip->position_fix == POS_FIX_POSBUF) {
+        if (chip->position_fix == POS_FIX_POSBUF ||
+            chip->position_fix == POS_FIX_AUTO) {
                 /* use the position buffer */
                 pos = *azx_dev->posbuf;
+                if (chip->position_fix == POS_FIX_AUTO &&
+                    azx_dev->period_intr == 1 && ! pos) {
+                        printk(KERN_WARNING
+                               "hda-intel: Invalid position buffer, "
+                               "using LPIB read method instead.\n");
+                        chip->position_fix = POS_FIX_NONE;
+                        goto read_lpib;
+                }
         } else {
+        read_lpib:
                 /* read LPIB */
                 pos = azx_sd_readl(azx_dev, SD_LPIB);
                 if (chip->position_fix == POS_FIX_FIFO)
@@ -1441,7 +1449,7 @@ static int __devinit azx_create(struct snd_card *card, struct pci_dev *pci,
         chip->irq = -1;
         chip->driver_type = driver_type;
 
-        chip->position_fix = position_fix ? position_fix : POS_FIX_POSBUF;
+        chip->position_fix = position_fix;
         chip->single_cmd = single_cmd;
 
 #if BITS_PER_LONG != 64