[PATCH] fix selector unit bug affecting some USB speakerphones

["Russ Cox" <rsc@swtch.com>]

My reading of the maintainers file is that
sound/usb/usbmixer.c belongs to perex@suse.cz
but I got no response to this message, so I am
resending it here.

Russ

---------- Forwarded message ----------
From: Russ Cox <rsc@swtch.com>
Date: Jun 21, 2007 7:48 PM
Subject: [PATCH] fix selector unit bug affecting some USB speakerphones
To: perex@suse.cz

Following the suggestion in this thread:
https://bugs.launchpad.net/ubuntu/+source/alsa-lib/+bug/26683
the correct upper bound on desc[0] is 5 + num_ins not 6 + num_ins,
because the index used later is 5+i, not 6+i.

This change makes my Vosky Chatterbox speakerphone work.
Apparently it also helps with the Minivox MV100.

Signed-off-by: Russ Cox <rsc@swtch.com>

---
 sound/usb/usbmixer.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sound/usb/usbmixer.c b/sound/usb/usbmixer.c
index 325d4b6..19776e7 100644
--- a/sound/usb/usbmixer.c
+++ b/sound/usb/usbmixer.c
@@ -1483,7 +1483,7 @@ static int parse_audio_selector_unit(struct
mixer_build *state, int unitid, unsi
        struct snd_kcontrol *kctl;
        char **namelist;

-       if (! num_ins || desc[0] < 6 + num_ins) {
+       if (! num_ins || desc[0] < 5 + num_ins) {
                snd_printk(KERN_ERR "invalid SELECTOR UNIT descriptor
%d\n", unitid);
                return -EINVAL;
        }
--
1.4.4.2