[RFC PATCH] tty: serial: Add 8250-core based omap driver

[Robert Nelson]

On Thu, Jul 3, 2014 at 8:25 AM, Felipe Balbi <balbi at ti.com> wrote:
> On Thu, Jul 03, 2014 at 12:34:11AM -0700, Tony Lindgren wrote:
>> * Robert Nelson <robertcnelson at gmail.com> [140702 12:27]:
>> > On Wed, Jul 2, 2014 at 2:09 PM, Aaro Koskinen <aaro.koskinen at iki.fi> wrote:
>> > > Hi,
>> > >
>> > > On Wed, Jul 02, 2014 at 11:09:32AM -0500, Felipe Balbi wrote:
>> > >> > It has been only tested as console UART.
>> > >> > The tty name is ttyS based instead of ttyO. How big is the pain here,
>> > >> > what could be the easiest way to provide compatibility?
>> > >>
>> > >> have been considering that myself for months. You could pass an optional
>> > >> argument to serial8250_register_8250_port() but that only solves part of
>> > >> the problem :-(
>>
>> Some kind of compability layer sure would be nice.
>>
>> > > When ttyS -> ttyO change was done on OMAP, compatibility was not an issue.
>> > > Why should we care about it now?
>> >
>> > It would be a good opportunity to force everyone to update their bootloader. ;)
>> >
>> > Besides the BeagleBoard forum is quiet now, no one is complaining
>> > about that old (ttyS -> ttyO) transition anymore..
>>
>> How about a Kconfig option to provide ttyO by default? The not even
>> do that if kernel has cmdline option nottyomap.
>
> what about single zImage ? I don't want to use ttyO on my
> Allwinner/Exynos/Snapdragon/whatever SoC just because OMAP is in the
> same image ;-)

What if we just kept it simple, leave the ttyO driver enabled and add
a warning (pr_info) that it's deprecated.  It's not like it's broken,
it just won't get later features or devices support added.

Regards,

-- 
Robert Nelson
http://www.rcn-ee.com/