diff options
Diffstat (limited to 'sound/usb/endpoint.c')
| -rw-r--r-- | sound/usb/endpoint.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index 825a06ce83a9..0cc64bd4d0a4 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -188,9 +188,17 @@ static void prepare_silent_urb(struct snd_usb_endpoint *ep, { struct urb *urb = ctx->urb; unsigned int offs = 0; + unsigned int extra = 0; + __le32 packet_length; int i; + /* For tx_length_quirk, put packet length at start of packet */ + if (ep->chip->tx_length_quirk) + extra = sizeof(packet_length); + for (i = 0; i < ctx->packets; ++i) { + unsigned int offset; + unsigned int length; int counts; if (ctx->packet_size[i]) @@ -198,15 +206,22 @@ static void prepare_silent_urb(struct snd_usb_endpoint *ep, 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; + length = counts * ep->stride; /* number of silent bytes */ + offset = offs * ep->stride + extra * i; + urb->iso_frame_desc[i].offset = offset; + urb->iso_frame_desc[i].length = length + extra; + if (extra) { + packet_length = cpu_to_le32(length); + memcpy(urb->transfer_buffer + offset, + &packet_length, sizeof(packet_length)); + } + memset(urb->transfer_buffer + offset + extra, + ep->silence_value, length); 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); + urb->transfer_buffer_length = offs * ep->stride + ctx->packets * extra; } /* |