From e8bdb6bbab60a8731f21823c86391f176d052348 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Fri, 11 Jun 2010 17:34:22 +0200 Subject: ALSA: usb-audio: fix UAC2 control value queries For RANGE requests, we should only query as much bytes as we're in fact interested in. For CUR requests, we shouldn't confuse the firmware with an overlong request but just ask for 2 bytes. This might need fixing in the future as it's not entirely clear when to dispatch 1-byte, 2-byte and 4-byte request blocks. For now, we assume everything is coded in 16bit - this works for all firmware implementations I've seen. Signed-off-by: Daniel Mack Reported-by: Alex Lee Signed-off-by: Takashi Iwai --- sound/usb/mixer.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'sound/usb/mixer.c') diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index a060d005e209..6939d0f517d9 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -297,20 +297,27 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret) { - unsigned char buf[14]; /* enough space for one range of 4 bytes */ + unsigned char buf[2 + 3*sizeof(__u16)]; /* enough space for one range */ unsigned char *val; - int ret; + int ret, size; __u8 bRequest; - bRequest = (request == UAC_GET_CUR) ? - UAC2_CS_CUR : UAC2_CS_RANGE; + if (request == UAC_GET_CUR) { + bRequest = UAC2_CS_CUR; + size = sizeof(__u16); + } else { + bRequest = UAC2_CS_RANGE; + size = sizeof(buf); + } + + memset(buf, 0, sizeof(buf)); ret = snd_usb_ctl_msg(cval->mixer->chip->dev, usb_rcvctrlpipe(cval->mixer->chip->dev, 0), bRequest, USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN, validx, cval->mixer->ctrlif | (cval->id << 8), - buf, sizeof(buf), 1000); + buf, size, 1000); if (ret < 0) { snd_printk(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n", @@ -318,6 +325,8 @@ static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int v return ret; } + /* FIXME: how should we handle multiple triplets here? */ + switch (request) { case UAC_GET_CUR: val = buf; -- cgit v1.2.3 From a5c7d797dcce3be5e77cd6ea62cc4920ededc32b Mon Sep 17 00:00:00 2001 From: Alexey Fisher Date: Wed, 23 Jun 2010 14:17:09 +0200 Subject: ALSA: usb-audio - Add volume resolution quirk for some Logitech webcams Some programs like Skype trying to set capture volume automatically. Normally it will tray, carefully step by step lover or higher, set the volume. In real word it work not really well, because devises and vendors lie about real audio settings. For example most Logitech webcams have 6400 or 3500 steps for capture volume. They do not tell that actual resolution is 384. So we have only 7 or 18 real steps. In this patch I set real resolution only for tested devices. Signed-off-by: Alexey Fisher Signed-off-by: Takashi Iwai --- sound/usb/mixer.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'sound/usb/mixer.c') diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 6939d0f517d9..736d134cc03c 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -1107,6 +1107,19 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc, } break; + case USB_ID(0x046d, 0x0809): + case USB_ID(0x046d, 0x0991): + /* Most audio usb devices lie about volume resolution. + * Most Logitech webcams have res = 384. + * Proboly there is some logitech magic behind this number --fishor + */ + if (!strcmp(kctl->id.name, "Mic Capture Volume")) { + snd_printk(KERN_INFO + "set resolution quirk: cval->res = 384\n"); + cval->res = 384; + } + break; + } snd_printdd(KERN_INFO "[%d] FU [%s] ch = %d, val = %d/%d/%d\n", -- cgit v1.2.3