A quick patch below (totally untested!) might do that. It's passing the device struct blindly, so not sure whether this would actually work for all dma_alloc_coherent().
On archs that have dma_ops such as powerpc (but I think x86 too nowadays) you cannot use the USB device for dma_* operations. You need to get up to the host controller device...
It -might- be worth looking at adding code to the USB stack to propagate the parent device dma_ops down to USB devices... hard to tell.
Cheers, Ben.
Takashi
diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c index 9edef46..6c82026 100644 --- a/sound/usb/usbaudio.c +++ b/sound/usb/usbaudio.c @@ -734,7 +734,7 @@ static void snd_complete_sync_urb(struct urb *urb) } }
+#ifdef USBAUDIO_VMALLOC_BUFFER /* get the physical page pointer at the given offset */ static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs, unsigned long offset) @@ -769,6 +769,24 @@ static int snd_pcm_free_vmalloc_buffer(struct snd_pcm_substream *subs) return 0; }
+#define preallocate_buffer(chip, pcm, stream) /* NOP */
+#else +#define snd_pcm_get_vmalloc_page NULL +#define snd_pcm_alloc_vmalloc_buffer snd_pcm_lib_malloc_pages +#define snd_pcm_free_vmalloc_buffer snd_pcm_lib_free_pages
+static int preallocate_buffer(struct snd_usb_audio *chip, struct snd_pcm *pcm,
int stream)+{
- struct snd_pcm_substream *subs = pcm->streams[stream].substream;
- if (!subs)
return 0;- return snd_pcm_lib_preallocate_pages(subs, SNDRV_DMA_TYPE_DEV,
chip->card->dev,1024 * 64, 1024 * 1024);+} +#endif
/*
- unlink active urbs.
@@ -2328,6 +2346,7 @@ static int add_audio_endpoint(struct snd_usb_audio *chip, int stream, struct aud err = snd_pcm_new_stream(as->pcm, stream, 1); if (err < 0) return err;
preallocate_buffer(chip, as->pcm, stream);@@ -2356,6 +2375,7 @@ static int add_audio_endpoint(struct snd_usb_audio *chip, int stream, struct aud else strcpy(pcm->name, "USB Audio");
preallocate_buffer(chip, pcm, stream); init_substream(as, stream, fp);
list_add(&as->list, &chip->pcm_list);