On Fri, 11 Jun 2021 12:24:40 +0200, Muni Sekhar wrote: > > On Fri, Jun 11, 2021 at 3:25 PM Takashi Iwai <tiwai@xxxxxxx> wrote: > > > > On Fri, 11 Jun 2021 10:43:01 +0200, > > Muni Sekhar wrote: > > > > > > On Fri, Jun 11, 2021 at 1:19 PM Takashi Iwai <tiwai@xxxxxxx> wrote: > > > > > > > > On Fri, 11 Jun 2021 09:02:44 +0200, > > > > Muni Sekhar wrote: > > > > > > > > > > Hi all, > > > > > > > > > > I am using a USB sound card(snd-usb-audio), and it fails while doing > > > > > the audio recording "arecord: pcm_read:2032: read error: Input/output > > > > > error". > > > > > > > > > > I noticed recording(arecord) audio data on a USB sound card fails at > > > > > SNDRV_PCM_IOCTL_READI_FRAMES is giving EIO. > > > > > > > > > > Can someone please clarify when the kernel returns EIO for Ioctl > > > > > SNDRV_PCM_IOCTL_READI_FRAMES? and is there a workaround for this? > > > > > > > > It's a problem of either your device (e.g. USB device firmware) or the > > > > kernel. Do you get any relevant kernel error messages? > > > dmesg log does not indicate any such error messages when arecord fails. > > > > Then it's likely a debug print in PCM core, which is suppressed as > > default. You can enable it via dyndbg stuff. It won't help much for > > diagnose at this stage, though. > Is it snd-pcm.ko ? In my system, this module gets loaded as mentioned below: > alsa-base.conf:15:install snd-pcm /sbin/modprobe --ignore-install > snd-pcm $CMDLINE_OPTS && { /sbin/modprobe --quiet --use-blacklist > snd-pcm-oss ; : ; } The dynamic debug can be enabled at any time via sysfs. > > > Is there a way to prove it as a USB device firmware issue or kernel issue? > > > > You can check strace output, for example. The PCM core is supposed to > > be bug-free regarding this, so it's about USB-audio driver, and the > > problem is specific to your device (other USB-audio devices work), > > hence it's very likely a firmware problem. > Please find the strace output in the attached file "strace_op.txt" > file. Does it gives any more information? Not really for fixing the problem itself :) Again, it's a problem in USB-audio driver, and that's likely a firmware problem. At best, contact with the hardware vendor. Takashi