From b7eb4a06e9980973755b7e95a6d97fb8decbf8fd Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Mon, 26 Jan 2009 08:08:34 +0100 Subject: sound: usb-audio: use normal number of frames for no-data URBs When sending a silence URB (before playback has started, or when it is paused), use the number of frames that would be normally sent instead of a single frame so that the rate at which completion interrupts arrive is consistent. Signed-off-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- sound/usb/usbaudio.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'sound/usb') diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c index c709b956322..417d557ed64 100644 --- a/sound/usb/usbaudio.c +++ b/sound/usb/usbaudio.c @@ -525,7 +525,7 @@ static int snd_usb_audio_next_packet_size(struct snd_usb_substream *subs) /* * Prepare urb for streaming before playback starts or when paused. * - * We don't have any data, so we send a frame of silence. + * We don't have any data, so we send silence. */ static int prepare_nodata_playback_urb(struct snd_usb_substream *subs, struct snd_pcm_runtime *runtime, @@ -537,13 +537,13 @@ static int prepare_nodata_playback_urb(struct snd_usb_substream *subs, offs = 0; urb->dev = ctx->subs->dev; - urb->number_of_packets = subs->packs_per_ms; - for (i = 0; i < subs->packs_per_ms; ++i) { + for (i = 0; i < ctx->packets; ++i) { counts = snd_usb_audio_next_packet_size(subs); urb->iso_frame_desc[i].offset = offs * stride; urb->iso_frame_desc[i].length = counts * stride; offs += counts; } + urb->number_of_packets = ctx->packets; urb->transfer_buffer_length = offs * stride; memset(urb->transfer_buffer, subs->cur_audiofmt->format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0, -- cgit v1.2.3-70-g09d2