[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>

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 016fbc2..c096606 100644 (file)
--- 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