Date: Wed, 2 Oct 2024 22:11:57 +0200 From: Alban Hertroys <haramrae@gmail.com> To: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@freebsd.org> Cc: freebsd-stable@freebsd.org Subject: Re: uaudio device re-attach and persisting dev.pcm.$pcm.bitperfect sysctl Message-ID: <8745F9FB-9CC1-476C-9445-DC0A7A76165F@gmail.com> In-Reply-To: <86ploiwxw8.fsf@ltc.des.dev> References: <F61ECC96-6FCB-4A4E-9EEC-8D6AF31A8A62@gmail.com> <86ploiwxw8.fsf@ltc.des.dev>
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> On 2 Oct 2024, at 13:24, Dag-Erling Sm=C3=B8rgrav <des@freebsd.org> =
wrote:
>=20
> Alban Hertroys <haramrae@gmail.com> writes:
>> I have a number of sysctl=E2=80=99s in /etc/sysctl.conf to tune my =
audio output:
>>=20
>> hw.snd.default_unit=3D2
>> hw.snd.maxautovchans=3D0
>> dev.pcm.2.play.vchans=3D0
>> dev.pcm.2.bitperfect=3D1
>=20
> This only works by accident because your DSP happens to be switched on
> and attached to pcm2 when sysctl.conf is processed during boot. If =
you
> boot your machine with the DSP switched off or unplugged, you will see
> errors during boot because these sysctl nodes do not exist until the =
DSP
> is turned on and the driver attaches to it. You need to set up devd =
to
> run the correct sysctl commands (with the correct device unit numbers,
> don't assume your DSP is always pcm2!) when your DSP is attached.
Those sysctl's happen to be what several posts on the FreeBSD forums =
advise for setting up USB DACs. That=E2=80=99s where I got my info when =
setting this up a while ago (during 13.1-RELEASE, I=E2=80=99d be a =
little hard-pressed to provide URL=E2=80=99s now). Just pointing out the =
trap there.
Meanwhile, several people here suggested that devd is the way to go =
about this. I had actually looked into that a bit, but that seemed to =
require a related device node in /dev, and there=E2=80=99s neither one =
for pcm nor for uaudio, so I discarded that as not being a viable =
option. Perhaps too soon.
I=E2=80=99ve been trying a bit, but I=E2=80=99m unfamiliar with =
devd.conf, so I got stuck at the point of:
notify 100 {
match "system" "USB";
match "subsystem" "DEVICE";
match "type" "ATTACH";
match "vendor" "0x152a";
match "product" "0x8750";
action "PCM=3D`sysctl dev.pcm | grep 'Topping D90SE' | cut -d . =
-f 3` && sysctl 'hw.snd.default_unit=3D${PCM} =
dev.pcm.${PCM}.play.vchans=3D0 dev.pcm.$
};
I can see devd looking to match uaudio0 and pcm2 devices to several =
names it knows (probably from other devd confs?), but it doesn=E2=80=99t =
seem to match my attempt. Let alone that it got around to attempting to =
parse my sh tidbit.
Sysctl reports the device as:
dev.uaudio.0.%pnpinfo: vendor=3D0x152a product=3D0x8750 devclass=3D0xef =
devsubclass=3D0x02 devproto=3D0x01 sernum=3D"" release=3D0x0188 =
mode=3Dhost intclass=3D0x01 intsubclass=3D0x01 intprotocol=3D0x20
dev.uaudio.0.%location: bus=3D0 hubaddr=3D5 port=3D4 devaddr=3D6 =
interface=3D0 ugen=3Dugen0.6dev.uaudio.0.%driver: uaudio
dev.uaudio.0.%desc: Topping D90SE, class 239/2, rev 2.00/1.88, addr 14
dev.uaudio.%parent:=20
Corrections and improvements are welcome. How to use the actual device =
name from the event as a variable in grep instead of hard-coding it, for =
example.
Meanwhile, I have my hopes up for what Christos comes up with.
Regards,
Alban Hertroys
--
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dan helpt het,
als die een punthoofd heeft.
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