Re: [PATCH 1/2] printk: nbcon: Introduce Braille helpers

[Samuel Thibault <samuel.thibault@ens-lyon.org>]

Hello,

Petr Mladek, le ven. 25 sept. 2026 16:34:12 +0200, a ecrit:
> Well, I guess that the driver was created for a particular Braille
> device.

Yes. It wouldn't be hard to add more.

> I wonder if there exists Braille devices working with other serial
> ports which are compatible...

I am not sure what the question is. There are braille devices connected
through good-old serial port, USB port, bluetooth, etc.

Petr Mladek, le ven. 25 sept. 2026 16:49:28 +0200, a ecrit:
> On Fri 2026-09-25 16:42:19, John Ogness wrote:
> > On 2026-09-25, Petr Mladek <pmladek@suse.com> wrote:
> > > This shows that braille_write() is called form printk() even when
> > > braille_co is not in console_list. It is called via vt_console_print()
> > > because the graphical console driver (ttyX) is registered.
> > 
> > But isn't that a bug? I thought Braille consoles were not supposed to be
> > handled by printk(). Even in this new series you added that exact
> > comment.
> 
> I believe that it is not a bug. I understand it the way that the
> Braille device should show everything that is shown on the virtual
> terminal. It should show the printk() messages when they are
> printed there by the related console driver.
> 
> It is just that printk() is only one source of messages shown
> on the terminal. The vt code maintains what is displayed.

That is the idea, yes.

Samuel