amixer: cset: check control is readable before reading it

alsa-project/alsa-utils pull request #63 was opened from ViorelSuman:

In current implementation cset command will fail on controls which are not readable, ie just writable. Check readable state prior calling snd_ctl_elem_read.

Signed-off-by: Viorel Suman viorel.suman@nxp.com

Request URL : https://github.com/alsa-project/alsa-utils/pull/63 Patch URL : https://github.com/alsa-project/alsa-utils/pull/63.patch Repository URL: https://github.com/alsa-project/alsa-utils