Getting USB serial to work closer to boot

[Zachary Kline]

Hi All,

I’m wondering what ideas people might have to get the USB serial devices to work closer to boot time? Could I possibly use the initial ram disk to load the appropriate modules? One of the things i really miss about earlier Speakup was that it theoretically worked almost from the moment you turned on the computer, and you could troubleshoot issues fairly easily with a serial synthesizer.

I’m using ArchLinux with the default 4.13 kernel, if that matters. I haven’t messed with kernel recompilation in a while, but if it would help I’m willing to try it.
Best,
Zack.

[John Covici]

You could build speakup into the kernel and build in the appropriate
modules -- I know this works well with plain serial, I don't know how
it would work with usb serial.

On Fri, 15 Sep 2017 21:38:16 -0400,

Post by Zachary Kline
Hi All,
I’m wondering what ideas people might have to get the USB serial devices to work closer to boot time? Could I possibly use the initial ram disk to load the appropriate modules? One of the things i really miss about earlier Speakup was that it theoretically worked almost from the moment you turned on the computer, and you could troubleshoot issues fairly easily with a serial synthesizer.
I’m using ArchLinux with the default 4.13 kernel, if that matters. I haven’t messed with kernel recompilation in a while, but if it would help I’m willing to try it.
Best,
Zack.
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[Samuel Thibault]

Post by John Covici
You could build speakup into the kernel and build in the appropriate
modules -- I know this works well with plain serial, I don't know how
it would work with usb serial.

It should just work too, you just need to specify the dev parameter for
the module.

Samuel

[Samuel Thibault]

Hello,

Post by Zachary Kline
I’m wondering what ideas people might have to get the USB serial devices to work closer to boot time? Could I possibly use the initial ram disk to load the appropriate modules?

That should just work, yes.

I don't remember how to tell initrd to load a specific module, but I
guess the documentation knows.

Samuel

[Zachary Kline]

Samuel,

I’ve actually noticed that if the module loads too early, the probe seems to fail. I presume this is because /dev/ttyUSB0 isn’t actually created yet. If I manually mod probe speakup_dectlk after system boot, it works as I’d expect.

This is a bit frustrating, but I don’t know how much can be done about it. Modifying the ignitrd didn’t seem to work as I expected.
Best,
Zack.

Post by Samuel Thibault
Hello,

Post by Zachary Kline
I’m wondering what ideas people might have to get the USB serial devices to work closer to boot time? Could I possibly use the initial ram disk to load the appropriate modules?

That should just work, yes.
I don't remember how to tell initrd to load a specific module, but I
guess the documentation knows.
Samuel
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Speakup mailing list
http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup

[Samuel Thibault]

Hello,

Post by Zachary Kline
I’ve actually noticed that if the module loads too early, the probe seems to fail. I presume this is because /dev/ttyUSB0 isn’t actually created yet.

Just realizing... Did you include the usbserial module to your initrd?

But yes, there's an initialization race issue. Perhaps you can use

softdep speakup_yoursynth pre: usbserial

to express the dependency?

Samuel