ALSA: USB-audio: Add offset parameter to copy_to_urb()

Preparation for adding Zoom R16/24 quirk.
No functional change.

Signed-off-by: Ricard Wanderlof <ricardw@axis.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index ee8dd9efb3ef6a0169dae16b29b757960a80703c..e3c5bc0df69d6aba12c7d1e0196e7ef825a25777 100644 (file)
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -1387,8 +1387,8 @@ static inline void fill_playback_urb_dsd_dop(struct snd_usb_substream *subs,
                subs->hwptr_done -= runtime->buffer_size * stride;
 }
 
-static void copy_to_urb(struct snd_usb_substream *subs,
-                      struct urb *urb, int stride, unsigned int bytes)
+static void copy_to_urb(struct snd_usb_substream *subs, struct urb *urb,
+                       int offset, int stride, unsigned int bytes)
 {
        struct snd_pcm_runtime *runtime = subs->pcm_substream->runtime;
 
@@ -1396,12 +1396,12 @@ static void copy_to_urb(struct snd_usb_substream *subs,
                /* err, the transferred area goes over buffer boundary. */
                unsigned int bytes1 =
                        runtime->buffer_size * stride - subs->hwptr_done;
-               memcpy(urb->transfer_buffer,
+               memcpy(urb->transfer_buffer + offset,
                       runtime->dma_area + subs->hwptr_done, bytes1);
-               memcpy(urb->transfer_buffer + bytes1,
+               memcpy(urb->transfer_buffer + offset + bytes1,
                       runtime->dma_area, bytes - bytes1);
        } else {
-               memcpy(urb->transfer_buffer,
+               memcpy(urb->transfer_buffer + offset,
                       runtime->dma_area + subs->hwptr_done, bytes);
        }
        subs->hwptr_done += bytes;
@@ -1488,7 +1488,7 @@ static void prepare_playback_urb(struct snd_usb_substream *subs,
                        subs->hwptr_done -= runtime->buffer_size * stride;
        } else {
                /* usual PCM */
-               copy_to_urb(subs, urb, stride, bytes);
+               copy_to_urb(subs, urb, 0, stride, bytes);
        }
 
        /* update delay with exact number of samples queued */