[alsa-devel] [PATCH] Mixer quirk for QuickCam E 3500

[Alexey Fisher]

Takashi Iwai schrieb:
> At Tue, 21 Jul 2009 23:10:42 +0200,
> Alexey Fisher wrote:
>> 1. E3500 report cval->max more than it actually can handel, so if you
>> set 95% capture level it will be muted.
>> 2. betwen cval->min and cval-max(real) is 2940 control units,
>> but real are only 7.
>> 3. we found only 7 real control units, with cval->res = 384,
>> but alsa can't handel less than 10 controls, so make it more
>> and set cval->res = 192.
>>
>> Signed-off-by: Alexey Fisher <bug-track at fisher-privat.net>
> 
> Thanks for the patch.  The added code looks almost good.
> But, it's better to put your code into another place, e.g. a bit
> later so that you don't insert it between the comment and the other
> code.  Also, if you use switch(), you need break.
> 
> In your case, simply put a new if () block with a proper comment
> after that switch() block.  It's not necessarily merged into a single
> switch.  The compiler should be clever enough.
> 
> Also, try to keep the patch checkpatch.pl-clean.  Run it once before
> submitting your patch.
> 
> Could you fix these and repost?
> 
> 
> thanks,
> 
> Takashi
> 
>> ---
>>  sound/usb/usbmixer.c |    7 +++++++
>>  1 files changed, 7 insertions(+), 0 deletions(-)
>>
>> diff --git a/sound/usb/usbmixer.c b/sound/usb/usbmixer.c
>> index 4bd3a7a..72562ee 100644
>> --- a/sound/usb/usbmixer.c
>> +++ b/sound/usb/usbmixer.c
>> @@ -995,6 +995,13 @@ static void build_feature_ctl(struct mixer_build *state, unsigned char *desc,
>>  	/* is not very clear from datasheets */
>>  	/* I hope that the min value is -15360 for newer firmware --jk */
>>  	switch (state->chip->usb_id) {
>> +	case USB_ID(0x046d, 0x09a4):
>> +		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
>> +			snd_printk(KERN_INFO "using volume control quirk for the QuickCam E3500\n");
>> +			cval->min = 6080;
>> +			cval->max = 8768;
>> +			cval->res = 192;
>> +		}
>>  	case USB_ID(0x0471, 0x0101):
>>  	case USB_ID(0x0471, 0x0104):
>>  	case USB_ID(0x0471, 0x0105):

There is some thing wrong with this. After suspend and resume this quirk 
not working. Even replug the cam not help, only reloading of 
snd_usb_sound will do it work again.

Thanks,
Alexey