ALSA: USB-audio: Break out creation of silent urbs from prepare_outbound_urb()
Refactoring in 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/endpoint.c b/sound/usb/endpoint.c
index a77d9c8..825a06c 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -183,13 +183,38 @@
ep->retire_data_urb(ep->data_subs, urb);
}
+static void prepare_silent_urb(struct snd_usb_endpoint *ep,
+ struct snd_urb_ctx *ctx)
+{
+ struct urb *urb = ctx->urb;
+ unsigned int offs = 0;
+ int i;
+
+ for (i = 0; i < ctx->packets; ++i) {
+ int counts;
+
+ if (ctx->packet_size[i])
+ counts = ctx->packet_size[i];
+ else
+ counts = snd_usb_endpoint_next_packet_size(ep);
+
+ urb->iso_frame_desc[i].offset = offs * ep->stride;
+ urb->iso_frame_desc[i].length = counts * ep->stride;
+ offs += counts;
+ }
+
+ urb->number_of_packets = ctx->packets;
+ urb->transfer_buffer_length = offs * ep->stride;
+ memset(urb->transfer_buffer, ep->silence_value,
+ offs * ep->stride);
+}
+
/*
* Prepare a PLAYBACK urb for submission to the bus.
*/
static void prepare_outbound_urb(struct snd_usb_endpoint *ep,
struct snd_urb_ctx *ctx)
{
- int i;
struct urb *urb = ctx->urb;
unsigned char *cp = urb->transfer_buffer;
@@ -201,24 +226,7 @@
ep->prepare_data_urb(ep->data_subs, urb);
} else {
/* no data provider, so send silence */
- unsigned int offs = 0;
- for (i = 0; i < ctx->packets; ++i) {
- int counts;
-
- if (ctx->packet_size[i])
- counts = ctx->packet_size[i];
- else
- counts = snd_usb_endpoint_next_packet_size(ep);
-
- urb->iso_frame_desc[i].offset = offs * ep->stride;
- urb->iso_frame_desc[i].length = counts * ep->stride;
- offs += counts;
- }
-
- urb->number_of_packets = ctx->packets;
- urb->transfer_buffer_length = offs * ep->stride;
- memset(urb->transfer_buffer, ep->silence_value,
- offs * ep->stride);
+ prepare_silent_urb(ep, ctx);
}
break;