On Wed, Aug 11, 2021 at 6:48 PM Muni Sekhar <munisekharrms@xxxxxxxxx> wrote: > > On Wed, Aug 11, 2021 at 6:19 PM vishnu <vardhanraj4143@xxxxxxxxx> wrote: > > > > can you paste output of > > arecord -l (list of capture devices). > $ arecord -l > **** List of CAPTURE Hardware Devices **** > card 0: USB [Plantronics .Audio 628 USB], device 0: USB Audio [USB Audio] > Subdevices: 1/1 > Subdevice #0: subdevice #0 > > > > Which device you are using and os. > > Does this instance is already open by default? like any video playing or something like that? > lsof does not catch it. > > > > > Yes you can stop pulse audio and try.. > > > > On Wed, Aug 11, 2021 at 6:17 PM Jaroslav Kysela <perex@xxxxxxxx> wrote: > >> > >> On 11. 08. 21 14:36, Muni Sekhar wrote: > >> > Hi All, > >> > > >> > $ cat /proc/asound/cards > >> > 0 [USB ]: USB-Audio - Plantronics .Audio 628 USB > >> > Plantronics Plantronics .Audio 628 USB at > >> > usb-0000:00:14.0-2, full speed > >> > > >> > I am using a Plantronics USB Audio headset. > >> > > >> > $ arecord --device hw:0,0 --channels 2 --format S16_LE --rate 44100Hz x.wav > >> > arecord: main:722: audio open error: Device or resource busy > >> > > >> > > >> > 'arecord' command always fails the first time after system boot in my > >> > system. But subsequent execution of the 'arecord' command runs fine. > >> > > >> > > >> > I've attached the strace log for the "audio open error: Device or > >> > resource busy" failure. Is there any fix available for this issue? > >> > >> You may check which other task blocks the PCM device: > >> > >> lsof /dev/snd/pcmC0D0c > It does not output any process. > $ lsof /dev/snd/pcmC0D0c > > 1st run: > ---------- > $ arecord --device hw:0,0 --channels 2 --format S16_LE --rate 44100Hz x.wav > arecord: main:722: audio open error: Device or resource busy > > 2nd run: > ---------- > $ arecord --device hw:0,0 --channels 2 --format S16_LE --rate 44100Hz x.wav > Recording WAVE 'x.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo > ^CAborted by signal Interrupt... > > > >> > >> I guess that it will be pulseaudio (device enumeration). I see that pulseaudio is getting loaded on invoking the 1st run of 'arecord' command. Here is the log: After system boot I verified that pulseaudio is not in the memory. test@test594:~$ uptime 21:39:27 up 0 min, 1 user, load average: 0.70, 0.25, 0.09 test@test594:~$ ls -ltr /dev/snd/controlC1 crw-rw---- 1 root audio 116, 2 Aug 13 21:38 /dev/snd/controlC1 test@test594:~$ ls -ltr /dev/snd/ total 0 crw-rw---- 1 root audio 116, 33 Aug 13 21:38 timer crw-rw---- 1 root audio 116, 1 Aug 13 21:38 seq crw-rw---- 1 root audio 116, 3 Aug 13 21:38 pcmC1D0p crw-rw---- 1 root audio 116, 4 Aug 13 21:38 pcmC1D0c crw-rw---- 1 root audio 116, 2 Aug 13 21:38 controlC1 drwxr-xr-x 2 root root 60 Aug 13 21:38 by-path drwxr-xr-x 2 root root 60 Aug 13 21:38 by-id test@test594:~$ lsof /dev/snd/controlC1 test@test594:~$ lsof /dev/snd/pcmC1D0c test@test594:~$ 1st run of 'arecord': ------------------------- I triggered 'arecord' after 2 mins of the system boot. In the 1st run, it failed with "Device or resource busy" and I see that pulseaudio loaded in the memory. Why does pulseaudio get triggered on running the alsa-utils command? How is the failure message "Device or resource busy" from the kernel code? test@test594:~$ arecord --device hw:1,0 --channels 2 --format S16_LE --rate 44100Hz x.wav arecord: main:722: audio open error: Device or resource busy test@test594:~$ test@test594:~$ lsof /dev/snd/pcmC1D0c COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME pulseaudi 1550 test mem CHR 116,4 463 /dev/snd/pcmC1D0c pulseaudi 1550 test 27u CHR 116,4 0t0 463 /dev/snd/pcmC1D0c test@test594:~$ lsof /dev/snd/controlC1 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME pulseaudi 1550 test 20u CHR 116,2 0t0 461 /dev/snd/controlC1 pulseaudi 1550 test 26u CHR 116,2 0t0 461 /dev/snd/controlC1 test@test594:~$ lsof /dev/snd/pcmC1D0p test@test594:~$ test@test594:~$ uptime 21:41:06 up 2 min, 1 user, load average: 0.20, 0.19, 0.08 2nd run of 'arecord': ------------------------- The subsequent run of arecord runs fine without any issues even though pulseaudio is still in memory. test@test594:~$ arecord --device hw:1,0 --channels 2 --format S16_LE --rate 44100Hz x.wav Recording WAVE 'x.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo ^CAborted by signal Interrupt... test@test594:~$ uptime 21:41:22 up 2 min, 1 user, load average: 0.14, 0.18, 0.08 test@test594:~$ What is the role of pulseaudio? Is there a way to disable it from running it? Disabling pulseaudio causes any issues while testing audio drivers? > >> > >> Jaroslav > >> > >> -- > >> Jaroslav Kysela <perex@xxxxxxxx> > >> Linux Sound Maintainer; ALSA Project; Red Hat, Inc. > > > > -- > Thanks, > Sekhar -- Thanks, Sekhar
