[PATCH 13/13] Nokia RX-51: Enable usbtty serial console by default

[Pali Rohár]

On Sunday 27 December 2020 18:28:25 Andy Shevchenko wrote:
> On Sun, Nov 29, 2020 at 6:53 PM Pali Rohár <pali at kernel.org> wrote:
> >
> > Now when usbtty serial console is fixed in U-Boot enable it for Nokia RX-51
> > board by default.
> >
> > CONFIG_CONSOLE_MUX is already used and U-Boot console is available for
> > all in/out devices. Therefore there is no need to have separate commands
> > 'run sercon', 'run usbcon' and 'run vgacon', so remove them.
> >
> > As space for U-Boot is limited to 256kB, disable some other unused options
> > so CONFIG_USB_TTY can be enabled.
> >
> > Nokia RX-51 does not have easily accessible UART serial console so the only
> > option for easy debugging is to use device's keyboard+screen or this usbtty
> > serial console over USB.
> 
> I think it's not a good idea to revive usbtty.

Well, but u-boot does not support anything else for Nokia N900. And main
issues here are musb bugs which this patch series is fixing. For
debugging is serial console (e.g. usbtty) needed.

> I was recently playing around f_serial.c (I can send you the half
> baked stuff, which by a lot of twisted code in DWC3 driver is not
> working properly, actually almost not working) and I think that would
> be the right thing to do.
> 
> usbtty quite old, intrusive way of serial console via USB supported
> only by outdated hardware (like this Nokia N-900), while f_serial
> gotta work on better recent base. And I believe musb should be, if
> needed, patched to support composite devices.
> 
> So, kinda disagreement from my side as a summary on this.
> But disclaimer, I'm not a maintainer here, just my 2 cents.
> 
> 
> 
> 
> -- 
> With Best Regards,
> Andy Shevchenko