On Sun, 16 Mar 2008 22:12:39 +0000 Giuliano Pochini <pochini@xxxxxxxx> wrote: > > Also, there seem to be failures at certain buffer sizes: > > > > $ ./test_buffers "hw:Layla3G,0,2" 429 > > buffer_size=18912 period_size=96 > > > > $ ./test_buffers "hw:Layla3G,0,2" 430 > > set_buffer_time_near: Invalid argument > > > > $ ./test_buffers "hw:Layla3G,0,2" 431 > > buffer_size=19008 period_size=96 > > This shouldn't happen. I'll give it a look. It seems that ALSA can't manage to find a working hwparams combo. The card has the following constraints: buffer size: 64-32768 frames period size: multiple of 32 frames periods: 2-220 It happens that ALSA restricts the allowable buffer size range to 18976-18976 which is very close to the requested 430ms. This is bad because the biggest multiple of 32 divisor of 18976 is 32. 18976/32 = 593 > maximum number of periods. return -EINVAL. BUFFER_TIME = (430294 430295) -> (430294 430295) Rule 8 [e20b3944]: RATE = [44100 44100] -> [44100 44100] Rule 15 [e20b38d0]: BUFFER_SIZE = [18976 32768] -> [18976 18976] Rule 17 [e20b38d0]: BUFFER_BYTES = [151808 262144] -> [151808 151808] Rule 19 [e20b3944]: BUFFER_TIME = (430294 430295) -> (430294 430295) Note that if you change the order of the hw_params_*() calls the problem goes away. It might show up again for some other values though. I don't know how to fix it. Any clue ?? -- Giuliano. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
