[BRLTTY] [PATCH] don't steal abused USB ids

[Dave Mielke]

[quoted lines by Stanislav Brabec on 2018/05/14 at 17:23 +0200]

>Several Braille devices abuse USB ids of UART Bridges. As a result,
>these devices cannot be automatically detected by USB id. Adding these
>USB ids to brltty udev rules breaks wide scale of other USB devices
>(USB-serial converters, GPSes, AVR ISP programmers, Arduino devices).

Yes, we're aware of this problem.

>brltty cannot steal these USB ids. If the manufacturers fills at least
>textual id of their devices, udev rules can use this for discrimination.

That's a good idea. Thanks. We'll look into it.

>If not, such devices cannot be auto detected. (Or they can be detected
>by an unsafe serial communication based helper.)

This turns out to be a matter of opinion. The users of braille devices with 
those identifiers wouldn't like it very much if their devices weren't detected. 
Also, please try to imagine how difficult it is for a blind person to figure 
out what the problem is when his braille debvice isn't working yet. It'd be 
like you trying to figure out what's wrong with your system while you have your 
monitor turned off. His braille device is his screen.

This is why I really do very much appreciate your suggestion to add some 
textual data to the rules. It's a much better way to resolve the problem.

>For now, let's comment abused USB devices out.
>
>Index: brltty-5.5/Autostart/Udev/rules

This patch won't solve the problem because that file is automatically 
generated. The script that generates it already does have an option to 
effectively do what your patch does - leave those devices in but as comments. 
Perhaps we should provide two files - all.rules and safe.rules. What do you 
think?

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