Re: [PATCH 1/9] drm: bridge/dw_hdmi-ahb-audio: add audio driver

From: Russell King - ARM Linux
Date: Tue Oct 06 2015 - 14:54:44 EST


On Tue, Oct 06, 2015 at 03:45:32PM -0300, Fabio Estevam wrote:
> On Tue, Oct 6, 2015 at 3:18 PM, Russell King - ARM Linux
> <linux@xxxxxxxxxxxxxxxx> wrote:
>
> > Sorry, I've been out for most of the day. There's no DT patches required.
> >
> > The dw_hdmi bridge driver creates its own platform device for the audio,
> > which should then bind to the dw_hdmi-ahb-audio driver using normal Linux
> > methods.
> >
> > I don't know what's wrong with your setup, for me, it just works:
> >
> > [ 1.358829] dwhdmi-imx 120000.hdmi: Detected HDMI controller 0x13:0xa:0xa0:0xc1
> > [ 1.377173] imx-drm display-subsystem: bound 120000.hdmi (ops dw_hdmi_imx_ops)
> > ...
> > [ 2.851343] ALSA device list:
> > [ 2.857364] #0: DW-HDMI rev 0x0a, irq 21
> >
> > as it always has done for me. There's nothing special about it.
>
> Great, got it to probe now:
>
> [ 7.454760] ALSA device list:
> [ 7.457764] #0: DW-HDMI rev 0x0a, irq 19
> [ 7.461990] #1: wm8962-audio
>
> There was a conflict and I resolved incorrectly here. Will try to play
> a wav file via aplay now.

Make sure you have the ALSA config file, as alsalib won't get on
with dw-hdmi only accepting 24-bit audio without this. A copy is
attached. It also tells ALSA how to deal with multi-channel audio
as well.

--
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
according to speedtest.net.
#
# All PCM must be 24-bit for easy kernel conversion.
# IEC958 formatted output can be sent directly.
#
# Direct-to-hardware converting to 24-bit output.
#
dw-hdmi-ahb-aud.pcm.hw-s24le {
@args [ CARD ]
@args.CARD { type string }
type linear
slave.pcm {
type hw
card $CARD
}
slave.format S24_LE
}

#
# Dmix hardware 24-bit output.
#
dw-hdmi-ahb-aud.pcm.dmix-s24le {
@args [ CARD ]
@args.CARD { type string }
type plug
slave.pcm { @func concat strings [ "dmix:" $CARD ",FORMAT=S24_LE" ] }
}

#
# Softvol with dmix output
#
dw-hdmi-ahb-aud.pcm.default {
@args [ CARD ]
@args.CARD { type string }
type asym
playback.pcm {
type softvol
slave.pcm {
@func refer name {
@func concat strings [
"cards."
{ @func card_driver card $CARD }
".pcm.dmix-s24le:CARD=" $CARD
]
}
}
control {
name "PCM Playback Volume"
card $CARD
}
}
}

#
# Common output path for front and surround outputs
#
dw-hdmi-ahb-aud.pcm.common.0 {
@args [ CARD ]
@args.CARD { type string }
type asym
playback.pcm {
type softvol
slave.pcm {
@func refer name {
@func concat strings [
"cards."
{ @func card_driver card $CARD }
".pcm.hw-s24le:CARD=" $CARD
]
}
}
control {
name "PCM Playback Volume"
card $CARD
}
}
}

<confdir:pcm/front.conf>

dw-hdmi-ahb-aud.pcm.front.0 cards.dw-hdmi-ahb-aud.pcm.common.0

# The mapping of ALSA channels to surround channels is very imprecise.
# ALSA uses a different terminology and speaker placement to the CEA
# surround positioning. CEA has the positioning of:
#
# LFE
# FL FLC FC FRC FR
#
#
# RL RLC RC RRC RR
#
# ALSA's idea is:
#
# LFE
# FL C FR
#
# SL SR
#
# RL RR
#
# We do our best to map between these representations.

<confdir:pcm/surround40.conf>

dw-hdmi-ahb-aud.pcm.surround40.0 {
@args [ CARD ]
@args.CARD { type string }
type empty
slave.pcm {
@func refer
name {
@func concat strings [
"cards.dw-hdmi-ahb-aud.pcm.common.0:CARD="
$CARD
]
}
}
}

# surround 41 and surround50 are (annoyingly) mapped to surround51
# We could do without stacking two 'route' plugins on top of each other

<confdir:pcm/surround41.conf>
<confdir:pcm/surround50.conf>
<confdir:pcm/surround51.conf>

dw-hdmi-ahb-aud.pcm.surround51.0 {
@args [ CARD ]
@args.CARD { type string }
type route
slave.pcm {
@func refer
name {
@func concat strings [
"cards.dw-hdmi-ahb-aud.pcm.common.0:CARD="
$CARD
]
}
}
ttable.0.0 1.0 # FL -> slave 0 -> hdmi 0 FL
ttable.1.1 1.0 # FR -> slave 1 -> hdmi 1 FR
ttable.2.4 1.0 # RL -> slave 4 -> hdmi 4 RL
ttable.3.5 1.0 # RR -> slave 5 -> hdmi 5 RR
ttable.4.3 1.0 # C -> slave 3 -> hdmi 3 FC
ttable.5.2 1.0 # LFE -> slave 2 -> hdmi 2 LFE
}

<confdir:pcm/surround71.conf>

dw-hdmi-ahb-aud.pcm.surround71.0 {
@args [ CARD ]
@args.CARD { type string }
type route
slave.pcm {
@func refer
name {
@func concat strings [
"cards.dw-hdmi-ahb-aud.pcm.common.0:CARD="
$CARD
]
}
}
slave.channels 8
ttable.0.0 1.0 # FL -> slave 0 -> hdmi 0 FL
ttable.1.1 1.0 # FR -> slave 1 -> hdmi 1 FR
ttable.2.6 1.0 # RL -> slave 6 -> hdmi 6 RLC/FLC
ttable.3.7 1.0 # RR -> slave 7 -> hdmi 7 RRC/FRC
ttable.4.3 1.0 # C -> slave 3 -> hdmi 3 FC
ttable.5.2 1.0 # LFE -> slave 2 -> hdmi 2 LFE
ttable.6.4 1.0 # SL -> slave 4 -> hdmi 4 RL
ttable.7.5 1.0 # SR -> slave 5 -> hdmi 5 RR
}

<confdir:pcm/hdmi.conf>

dw-hdmi-ahb-aud.pcm.hdmi.0 {
@args [ CARD AES0 AES1 AES2 AES3 ]
@args.CARD { type string }
@args.AES0 { type integer }
@args.AES1 { type integer }
@args.AES2 { type integer }
@args.AES3 { type integer }
type iec958
slave.pcm {
type hw
card $CARD
}
slave.format IEC958_SUBFRAME_LE
# $AES3 must be correct for some AV receivers to accept the stream
status [ $AES0 $AES1 $AES2 $AES3 ]
}

<confdir:pcm/iec958.conf>

dw-hdmi-ahb-aud.pcm.iec958.0 cards.dw-hdmi-ahb-aud.pcm.hdmi.0