[alsa-devel] amixer error

[Takashi Iwai]

At Tue, 11 Nov 2008 17:15:15 +0530,
Arun KS wrote:
> 
> On Tue, Nov 11, 2008 at 4:08 PM, Takashi Iwai <tiwai at suse.de> wrote:
> > At Tue, 11 Nov 2008 15:55:38 +0530,
> > Arun KS wrote:
> >>
> >> Hi,
> >>
> >> I am getting an error for amixer, but my amixer controls works fine.
> >>
> >> Here is the log:
> >>
> >> [root at OMAP2530EVM ~]#
> >> [root at OMAP2530EVM ~]#
> >> [root at OMAP2530EVM ~]#
> >> [root at OMAP2530EVM ~]# amixer
> >> amixer: Mixer default load error: Operation not permitted
> >
> > How about checking via strace?
> 
> Below is the strace output:
...
> open("/dev/snd/controlC0", O_RDWR)      = 3
> ioctl(3, USBDEVFS_CONTROL, 0xbea498fc)  = 0
> fcntl64(3, F_GETFL)                     = 0x2 (flags O_RDWR)
> fcntl64(3, F_SETFL, O_RDWR|O_NONBLOCK)  = 0
> ioctl(3, USBDEVFS_RELEASEINTERFACE, 0xbea49980) = 0
> ioctl(3, USBDEVFS_RELEASEINTERFACE, 0xbea49980) = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492c0)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492e0)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492e0)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492e0)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492e0)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492d8)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492c0)    = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492c0)    = 0
> ioctl(3, USBDEVFS_CONNECTINFO, 0xbea49718) = 0
> ioctl(3, USBDEVFS_IOCTL, 0xbea492c0)    = -1 EPERM (Operation not permitted)

Weird.  USBDEVFS_IOCTL corresponds to SNDRV_IOCTL_ELEM_REPLACE,
and USBDEVFS_CONNECTINFO to SNDRV_IOCTL_ELEM_ADD.
[some strace versions don't show SNDRV_* ioctls because they are defined
 via enum instead of #define in asound.h...]
These are for user-defined control elements.
And, strace shows that you don't use any ~/.asound or /etc/asound.conf...


Takashi