cros/audio/alsa_utils.py

# Copyright (c) 2013 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import logging
import re
import subprocess

from autotest_lib.client.common_lib import error
from autotest_lib.client.common_lib import utils
from autotest_lib.client.cros.audio import cmd_utils


ACONNECT_PATH = '/usr/bin/aconnect'
ARECORD_PATH = '/usr/bin/arecord'
APLAY_PATH = '/usr/bin/aplay'
AMIXER_PATH = '/usr/bin/amixer'
CARD_NUM_RE = re.compile(r'(\d+) \[.*\]:')
CLIENT_NUM_RE = re.compile(r'client (\d+):')
DEV_NUM_RE = re.compile(r'.* \[.*\], device (\d+):')
CONTROL_NAME_RE = re.compile(r"name='(.*)'")
SCONTROL_NAME_RE = re.compile(r"Simple mixer control '(.*)'")

CARD_PREF_RECORD_DEV_IDX = {
    'bxtda7219max': 3,
}

def _get_format_args(channels, bits, rate):
    args = ['-c', str(channels)]
    args += ['-f', 'S%d_LE' % bits]
    args += ['-r', str(rate)]
    return args


def get_num_soundcards():
    '''Returns the number of soundcards.

    Number of soundcards is parsed from /proc/asound/cards.
    Sample content:

      0 [PCH            ]: HDA-Intel - HDA Intel PCH
                           HDA Intel PCH at 0xef340000 irq 103
      1 [NVidia         ]: HDA-Intel - HDA NVidia
                           HDA NVidia at 0xef080000 irq 36
    '''

    card_id = None
    with open('/proc/asound/cards', 'r') as f:
        for line in f:
            match = CARD_NUM_RE.search(line)
            if match:
                card_id = int(match.group(1))
    if card_id is None:
        return 0
    else:
        return card_id + 1


def _get_soundcard_controls(card_id):
    '''Gets the controls for a soundcard.

    @param card_id: Soundcard ID.
    @raise RuntimeError: If failed to get soundcard controls.

    Controls for a soundcard is retrieved by 'amixer controls' command.
    amixer output format:

      numid=32,iface=CARD,name='Front Headphone Jack'
      numid=28,iface=CARD,name='Front Mic Jack'
      numid=1,iface=CARD,name='HDMI/DP,pcm=3 Jack'
      numid=8,iface=CARD,name='HDMI/DP,pcm=7 Jack'

    Controls with iface=CARD are parsed from the output and returned in a set.
    '''

    cmd = [AMIXER_PATH, '-c', str(card_id), 'controls']
    p = cmd_utils.popen(cmd, stdout=subprocess.PIPE)
    output, _ = p.communicate()
    if p.wait() != 0:
        raise RuntimeError('amixer command failed')

    controls = set()
    for line in output.splitlines():
        if not 'iface=CARD' in line:
            continue
        match = CONTROL_NAME_RE.search(line)
        if match:
            controls.add(match.group(1))
    return controls


def _get_soundcard_scontrols(card_id):
    '''Gets the simple mixer controls for a soundcard.

    @param card_id: Soundcard ID.
    @raise RuntimeError: If failed to get soundcard simple mixer controls.

    Simple mixer controls for a soundcard is retrieved by 'amixer scontrols'
    command.  amixer output format:

      Simple mixer control 'Master',0
      Simple mixer control 'Headphone',0
      Simple mixer control 'Speaker',0
      Simple mixer control 'PCM',0

    Simple controls are parsed from the output and returned in a set.
    '''

    cmd = [AMIXER_PATH, '-c', str(card_id), 'scontrols']
    p = cmd_utils.popen(cmd, stdout=subprocess.PIPE)
    output, _ = p.communicate()
    if p.wait() != 0:
        raise RuntimeError('amixer command failed')

    scontrols = set()
    for line in output.splitlines():
        match = SCONTROL_NAME_RE.findall(line)
        if match:
            scontrols.add(match[0])
    return scontrols


def get_first_soundcard_with_control(cname, scname):
    '''Returns the soundcard ID with matching control name.

    @param cname: Control name to look for.
    @param scname: Simple control name to look for.
    '''

    cpat = re.compile(r'\b%s\b' % cname, re.IGNORECASE)
    scpat = re.compile(r'\b%s\b' % scname, re.IGNORECASE)
    for card_id in xrange(get_num_soundcards()):
        for pat, func in [(cpat, _get_soundcard_controls),
                          (scpat, _get_soundcard_scontrols)]:
            if any(pat.search(c) for c in func(card_id)):
                return card_id
    return None


def get_soundcard_names():
    '''Returns a dictionary of card names, keyed by card number.'''

    cmd = "alsa_helpers -l"
    try:
        output = utils.system_output(command=cmd, retain_output=True)
    except error.CmdError:
        raise RuntimeError('alsa_helpers -l failed to return card names')

    return dict((index, name) for index, name in (
        line.split(',') for line in output.splitlines()))


def get_default_playback_device():
    '''Gets the first playback device.

    Returns the first playback device or None if it fails to find one.
    '''

    card_id = get_first_soundcard_with_control(cname='Headphone Jack',
                                               scname='Headphone')
    if card_id is None:
        return None
    return 'plughw:%d' % card_id

def get_record_card_name(card_idx):
    '''Gets the recording sound card name for given card idx.

    Returns the card name inside the square brackets of arecord output lines.
    '''
    card_name_re = re.compile(r'card %d: .*?\[(.*?)\]' % card_idx)
    cmd = [ARECORD_PATH, '-l']
    p = cmd_utils.popen(cmd, stdout=subprocess.PIPE)
    output, _ = p.communicate()
    if p.wait() != 0:
        raise RuntimeError('arecord -l command failed')

    for line in output.splitlines():
        match = card_name_re.search(line)
        if match:
            return match.group(1)
    return None


def get_record_device_supported_channels(device):
    '''Gets the supported channels for the record device.

    @param device: The device to record the audio. E.g. hw:0,1

    Returns the supported values in integer in a list for the device.
    If the value doesn't exist or the command fails, return None.
    '''
    cmd = "alsa_helpers --device %s --get_capture_channels" % device
    try:
        output = utils.system_output(command=cmd, retain_output=True)
    except error.CmdError:
        logging.error("Fail to get supported channels for %s", device)
        return None

    supported_channels = output.splitlines()
    if not supported_channels:
        logging.error("Supported channels are empty for %s", device)
        return None
    return [int(i) for i in supported_channels]


def get_default_record_device():
    '''Gets the first record device.

    Returns the first record device or None if it fails to find one.
    '''

    card_id = get_first_soundcard_with_control(cname='Mic Jack', scname='Mic')
    if card_id is None:
        return None

    card_name = get_record_card_name(card_id)
    if CARD_PREF_RECORD_DEV_IDX.has_key(card_name):
        return 'plughw:%d,%d' % (card_id, CARD_PREF_RECORD_DEV_IDX[card_name])

    # Get first device id of this card.
    cmd = [ARECORD_PATH, '-l']
    p = cmd_utils.popen(cmd, stdout=subprocess.PIPE)
    output, _ = p.communicate()
    if p.wait() != 0:
        raise RuntimeError('arecord -l command failed')

    dev_id = 0
    for line in output.splitlines():
        if 'card %d:' % card_id in line:
            match = DEV_NUM_RE.search(line)
            if match:
                dev_id = int(match.group(1))
                break
    return 'plughw:%d,%d' % (card_id, dev_id)


def _get_sysdefault(cmd):
    p = cmd_utils.popen(cmd, stdout=subprocess.PIPE)
    output, _ = p.communicate()
    if p.wait() != 0:
        raise RuntimeError('%s failed' % cmd)

    for line in output.splitlines():
        if 'sysdefault' in line:
            return line
    return None


def get_sysdefault_playback_device():
    '''Gets the sysdefault device from aplay -L output.'''

    return _get_sysdefault([APLAY_PATH, '-L'])


def get_sysdefault_record_device():
    '''Gets the sysdefault device from arecord -L output.'''

    return _get_sysdefault([ARECORD_PATH, '-L'])


def playback(*args, **kwargs):
    '''A helper funciton to execute playback_cmd.

    @param kwargs: kwargs passed to playback_cmd.
    '''
    cmd_utils.execute(playback_cmd(*args, **kwargs))


def playback_cmd(
        input, duration=None, channels=2, bits=16, rate=48000, device=None):
    '''Plays the given input audio by the ALSA utility: 'aplay'.

    @param input: The input audio to be played.
    @param duration: The length of the playback (in seconds).
    @param channels: The number of channels of the input audio.
    @param bits: The number of bits of each audio sample.
    @param rate: The sampling rate.
    @param device: The device to play the audio on. E.g. hw:0,1
    @raise RuntimeError: If no playback device is available.
    '''
    args = [APLAY_PATH]
    if duration is not None:
        args += ['-d', str(duration)]
    args += _get_format_args(channels, bits, rate)
    if device is None:
        device = get_default_playback_device()
        if device is None:
            raise RuntimeError('no playback device')
    else:
        device = "plug%s" % device
    args += ['-D', device]
    args += [input]
    return args


def record(*args, **kwargs):
    '''A helper function to execute record_cmd.

    @param kwargs: kwargs passed to record_cmd.
    '''
    cmd_utils.execute(record_cmd(*args, **kwargs))


def record_cmd(
        output, duration=None, channels=1, bits=16, rate=48000, device=None):
    '''Records the audio to the specified output by ALSA utility: 'arecord'.

    @param output: The filename where the recorded audio will be stored to.
    @param duration: The length of the recording (in seconds).
    @param channels: The number of channels of the recorded audio.
    @param bits: The number of bits of each audio sample.
    @param rate: The sampling rate.
    @param device: The device used to recorded the audio from. E.g. hw:0,1
    @raise RuntimeError: If no record device is available.
    '''
    args = [ARECORD_PATH]
    if duration is not None:
        args += ['-d', str(duration)]
    args += _get_format_args(channels, bits, rate)
    if device is None:
        device = get_default_record_device()
        if device is None:
            raise RuntimeError('no record device')
    else:
        device = "plug%s" % device
    args += ['-D', device]
    args += [output]
    return args


def mixer_cmd(card_id, cmd):
    '''Executes amixer command.

    @param card_id: Soundcard ID.
    @param cmd: Amixer command to execute.
    @raise RuntimeError: If failed to execute command.

    Amixer command like ['set', 'PCM', '2dB+'] with card_id 1 will be executed
    as:
        amixer -c 1 set PCM 2dB+

    Command output will be returned if any.
    '''

    cmd = [AMIXER_PATH, '-c', str(card_id)] + cmd
    p = cmd_utils.popen(cmd, stdout=subprocess.PIPE)
    output, _ = p.communicate()
    if p.wait() != 0:
        raise RuntimeError('amixer command failed')
    return output


def get_num_seq_clients():
    '''Returns the number of seq clients.

    The number of clients is parsed from aconnect -io.
    This is run as the chronos user to catch permissions problems.
    Sample content:

      client 0: 'System' [type=kernel]
          0 'Timer           '
          1 'Announce        '
      client 14: 'Midi Through' [type=kernel]
          0 'Midi Through Port-0'

    @raise RuntimeError: If no seq device is available.
    '''
    cmd = [ACONNECT_PATH, '-io']
    output = cmd_utils.execute(cmd, stdout=subprocess.PIPE, run_as='chronos')
    num_clients = 0
    for line in output.splitlines():
        match = CLIENT_NUM_RE.match(line)
        if match:
            num_clients += 1
    return num_clients

def convert_device_name(cras_device_name):
    '''Converts cras device name to alsa device name.

    @returns: alsa device name that can be passed to aplay -D or arecord -D.
              For example, if cras_device_name is "kbl_r5514_5663_max: :0,1",
              this function will return "hw:0,1".
    '''
    tokens = cras_device_name.split(":")
    return "hw:%s" % tokens[2]