diff options
| author | Takashi Iwai <tiwai@suse.de> | 2015-01-23 16:54:36 +0100 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2015-01-28 07:21:45 +0100 |
| commit | c8491535d7f1a1e8f7f3e0d31e8f7525809c98a1 (patch) | |
| tree | a5d1a2f794129ed78e6e8b0d21959fb36b3843c1 /sound/usb/line6 | |
| parent | e90576c5955c83cd7e8c191b47f70d1946015041 (diff) | |
| download | linux-c8491535d7f1a1e8f7f3e0d31e8f7525809c98a1.tar.bz2 | |
ALSA: line6: Do clipping in volume / monitor manipulations
Tested-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/line6')
| -rw-r--r-- | sound/usb/line6/playback.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/sound/usb/line6/playback.c b/sound/usb/line6/playback.c index 750d91dced57..cbcd97f5d629 100644 --- a/sound/usb/line6/playback.c +++ b/sound/usb/line6/playback.c @@ -37,7 +37,8 @@ static void change_volume(struct urb *urb_out, int volume[], buf_end = p + urb_out->transfer_buffer_length / sizeof(*p); for (; p < buf_end; ++p) { - *p = (*p * volume[chn & 1]) >> 8; + int val = (*p * volume[chn & 1]) >> 8; + *p = clamp(val, 0x7fff, -0x8000); ++chn; } } else if (bytes_per_frame == 6) { @@ -51,6 +52,7 @@ static void change_volume(struct urb *urb_out, int volume[], val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16); val = (val * volume[chn & 1]) >> 8; + val = clamp(val, 0x7fffff, -0x800000); p[0] = val; p[1] = val >> 8; p[2] = val >> 16; @@ -118,8 +120,10 @@ static void add_monitor_signal(struct urb *urb_out, unsigned char *signal, po = (short *)urb_out->transfer_buffer; buf_end = po + urb_out->transfer_buffer_length / sizeof(*po); - for (; po < buf_end; ++pi, ++po) - *po += (*pi * volume) >> 8; + for (; po < buf_end; ++pi, ++po) { + int val = *po + ((*pi * volume) >> 8); + *po = clamp(val, 0x7fff, -0x8000); + } } /* |