Am Mittwoch 24 März 2010 schrieb Jan Depner:
I suggest adding some printk()s to the driver and see what it actually does and which values it passes around. Most probably there is more differences in the data format, and descriptors and/or message blocks have different meanings for this hardware model.
I did as suggested and got back reasonable appearing numbers forrate, use_packsize, and period_frames of 44100, 36, and 256 respectively but am not sure how to relate this to my interface.
I heard the US-1641 uses bulk and/or iso packets, while US-122L uses iso only. so snd_usb_us122l would need some deep tweaking. also all the incantation stuff looks propably different.
Is there some documentation somewhere that would explain the output of lsusb -v with respect to variable names in us122l.c.
erm, no. there are the interface and endpoint numbers.
My problem here is that I don't know what would actually be reasonable for this interface nor how to find out.
usbsnoop and/or the developers at http://usbaudio.com.
Many thanks for your help with this. Karsten had asked me to getback with him if I got one of these but my email to him must have gone to the spam filter as I haven't heard anything.
no spam filters, just work and short hollidays.
looking back at developing snd_usb_us122l, i'm unsure if I spent my time wisely: the actual hardware one can buy now doesn't talk to the driver anymore. and i'm busy caring for real life, which i've been omitting a tad too much that time.
If in doubt, don't bother hacking on the tascam, enjoy spring instead!
regards, Karsten