[alsa-devel] [PATCH] add Steinberg UR44 USB Audio Interface support to quirks-table

[Cyrus Harmon]

Dear Takashi,

Sorry for the delay in getting back to this. Your instructions seem 
close, but I've run into the following issues:

1. the module is installed in  /lib/modules/`uname -r`/extra instead of 
kernel/sound/usb

2. I can get around that with:

sudo insmod /lib/modules/`uname -r`/extra/snd-usbmidi-lib.ko
sudo insmod /lib/modules/`uname -r`/extra/snd-usb-audio.ko

but there's probably a better way.

3. I can't do the same tricks with snd-pcm as I get the following error:

sly at madbox:/lib/modules/3.19.0-rc7-local$ sudo modprobe -r snd-pcm
modprobe: FATAL: Module snd_pcm is in use.

Is there a way to disable snd_pcm and reload the module? Barring that, I 
at least want to be able to install the new snd_pcm and reboot, without 
having to rebuild the whole kernel, so solving problem 1 would 
presumably help for that.

Thanks for your help!

Cyrus

On 11/06/2014 08:49 AM, Takashi Iwai wrote:
> At Thu, 06 Nov 2014 08:05:43 -0800 Cyrus Harmon wrote:
>> On a somewhat related note, is there a way to apply changes to things 
>> in, say, sound/usb and compile/install those changes without a few 
>> kernel rebuild/install? Or, even better, without a reboot? Would 
>> certainly shorting the debug cycle time for me. In this case I'm 
>> interested in finding out what quirk->type is when it gets to 
>> snd_usb_create_quirk as it looks like the function in the quirk_funcs 
>> table that gets called here produces the first suspect error. Adding 
>> a dev_info, followed by a kernel rebuild, reinstall, reboot (and the 
>> fact that my broken nvidia drivers require reinstalling the video 
>> driver every time I install a new kernel) makes for a tedious process!
> It's a standard procedure, something like... % mkdir /somewhere % cd 
> /somewhere % cp -a /there/linux/sound . % patch -p1 < your-usb.patch % 
> make -C /lib/modules/`uname -r`/build M=$PWD/sound/usb % su # make -C 
> /lib/modules/`uname -r`/build M=$PWD/sound/usb modules_install # 
> modprobe -r snd-usb-audio # modprobe snd-usb-audio Takashi