It is unlikely that your patch fix the problem since none of the drivers of those users have a volume control with multi channel
Only two users have drivers which does not have capture channel map (e.g. cmipci and intel8x0)
it is not clear why hda-intel can trigger the bug, the acer aspire 7540 has hda modem codec with channel mode and mic, line in jacks
It is unlikely that your patch fix the problem since none of the drivers of those users have a volume control with multi channel
Only two users have drivers which does not have capture channel map (e.g. cmipci and intel8x0)
it is not clear why hda-intel can trigger the bug, the acer aspire 7540 has hda modem codec with channel mode and mic, line in jacks