Comment 35 for bug 1166529

def parseoptions():
    from optparse import OptionParser
    parser = OptionParser()
    parser.add_option("-c", "--card", dest="cardindex", default=0, metavar="CARD",
        help="card index (as can be seen in /proc/asound/cards)")
    parser.add_option("-d", "--codec", dest="codecindex", default=0, metavar="CODEC",
        help="codec device index (as can be seen in /proc/asound/cardX/codecY)")
    parser.add_option("-a", "--allpins", dest="tryallpins", default=False,
        action="store_true",
        help="also check pins which (probably) are not physical jacks")
    (options, args) = parser.parse_args()
    return int(options.cardindex), int(options.codecindex), options.tryallpins

https://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/?id=825315bc5b5c33e5af5124ff100ef05a30ad722f

seem have three capture devices

info++;
+ info->name = "CA0132 Analog Mic-In2";
+ info->stream[SNDRV_PCM_STREAM_CAPTURE] = ca0132_pcm_analog_capture;
+ info->stream[SNDRV_PCM_STREAM_CAPTURE].substreams = 1;
+ info->stream[SNDRV_PCM_STREAM_CAPTURE].nid = spec->adcs[1];
+ codec->num_pcms++;
+
+ info++;
+ info->name = "CA0132 What U Hear";
+ info->stream[SNDRV_PCM_STREAM_CAPTURE] = ca0132_pcm_analog_capture;
+ info->stream[SNDRV_PCM_STREAM_CAPTURE].substreams = 1;
+ info->stream[SNDRV_PCM_STREAM_CAPTURE].nid = spec->adcs[2];
+ codec->num_pcms++;