OpenWrt Forum Archive

Topic: [alsa-lib] unable to open timer + unable to initialize poll_fd

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Post #1
gerrydoro
16 Aug 2017, 22:25

Just installed OpenWRT trunk on my HG553, then I Installed all the kmods for usb support and audio support and finally I installed shairport-sync but something gone wrong...

root@HG553:~# lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 004: ID 0d8c:013c C-Media Electronics, Inc. CM108 Audio Controller
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
root@HG553:~# alsactl init
Found hardware: "USB-Audio" "USB Mixer" "USB0d8c:013c" "" ""
Hardware is initialized using a generic method
root@HG553:~# shairport-sync
Successful Startup
ALSA lib pcm_direct.c:1421:(snd1_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:1183:(snd_pcm_dmix_open) unable to initialize poll_fd
ALSA lib pcm_direct.c:1421:(snd1_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:1183:(snd_pcm_dmix_open) unable to initialize poll_fd
ALSA lib pcm_direct.c:1421:(snd1_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:1183:(snd_pcm_dmix_open) unable to initialize poll_fd
ALSA lib pcm_direct.c:1421:(snd1_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
...
...
Post #2
vmark
13 Oct 2017, 20:03

Hi.
Did you find a solution?

I am facing the same problem...

root@OpenWrt:~# aplay --dump-hw-params
ALSA lib pcm_direct.c:1421:(snd1_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:1183:(snd_pcm_dmix_open) unable to initialize poll_fd
aplay: main:722: audio open error: No such device
root@OpenWrt:~# lsusb
Bus 001 Device 006: ID 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)
Bus 001 Device 005: ID 04d8:000a Microchip Technology, Inc. CDC RS-232 Emulation Demo
Bus 001 Device 004: ID 14cd:6116 Super Top M6116 SATA Bridge
Bus 001 Device 003: ID 0d8c:000c C-Media Electronics, Inc. Audio Adapter
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 1a40:0201 Terminus Technology Inc. FE 2.1 7-port Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
root@OpenWrt:~# lsmod | grep snd
input_core             24934  1 snd
snd                    33825 10 snd_usb_audio,snd_usbmidi_lib,snd_compress,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer,snd_rawmidi,snd_seq_device,snd_hwdep
snd_compress            6143  0 
snd_hwdep               4078  1 snd_usb_audio
snd_mixer_oss          11161  1 snd_pcm_oss
snd_pcm                56260  2 snd_usb_audio,snd_pcm_oss
snd_pcm_oss            33137  0 
snd_rawmidi            14410  1 snd_usbmidi_lib
snd_seq_device          1983  1 snd_rawmidi
snd_timer              14494  0 
snd_usb_audio         100790  0 
snd_usbmidi_lib        15729  1 snd_usb_audio
soundcore               3836  1 snd
usbcore               120322 19 snd_usb_audio,snd_usbmidi_lib,ums_usbat,ums_sddr55,ums_sddr09,ums_karma,ums_jumpshot,ums_isd200,ums_freecom,ums_datafab,ums_cypress,ums_alauda,cdc_acm,ledtrig_usbdev,usb_storage,ohci_platform,ohci_hcd,ehci_platform,ehci_hcd

However madplay works nicely - I hear the mp3 music.

(Last edited by vmark on 13 Oct 2017, 20:11)

Post #4
majid.it
18 Oct 2017, 13:55
vmark wrote:

After checking poll_df, I found the problem:
Details here: https://git.lede-project.org/?p=source. … 838f9bf2af


Thanks so much and you cant imagine how much I appreciate your answer. I was stuck with this error. It helped me so much.

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