ALSA: usb-audio: parse more format descriptors with structs

[safe/jmp/linux-2.6] / sound / pci / cmipci.c

diff --git a/sound/pci/cmipci.c b/sound/pci/cmipci.c
index 1ded64e..329968e 100644 (file)
--- a/sound/pci/cmipci.c
+++ b/sound/pci/cmipci.c
@@ -941,13 +941,21 @@ static snd_pcm_uframes_t snd_cmipci_pcm_pointer(struct cmipci *cm, struct cmipci
                                                struct snd_pcm_substream *substream)
 {
        size_t ptr;
-       unsigned int reg;
+       unsigned int reg, rem, tries;
+
        if (!rec->running)
                return 0;
 #if 1 // this seems better..
        reg = rec->ch ? CM_REG_CH1_FRAME2 : CM_REG_CH0_FRAME2;
-       ptr = rec->dma_size - (snd_cmipci_read_w(cm, reg) + 1);
-       ptr >>= rec->shift;
+       for (tries = 0; tries < 3; tries++) {
+               rem = snd_cmipci_read_w(cm, reg);
+               if (rem < rec->dma_size)
+                       goto ok;
+       } 
+       printk(KERN_ERR "cmipci: invalid PCM pointer: %#x\n", rem);
+       return SNDRV_PCM_POS_XRUN;
+ok:
+       ptr = (rec->dma_size - (rem + 1)) >> rec->shift;
 #else
        reg = rec->ch ? CM_REG_CH1_FRAME1 : CM_REG_CH0_FRAME1;
        ptr = snd_cmipci_read(cm, reg) - rec->offset;