Re: [PATCH 4/5] tty/hw: move hardware drivers to drivers/tty/hw

Mike Frysinger
2010-08-30T15:26:27Z

On Mon, Aug 30, 2010 at 11:25, Arnd Bergmann wrote:
> On Monday 30 August 2010, Mike Frysinger wrote:
>> On Mon, Aug 30, 2010 at 08:28, Arnd Bergmann wrote:
>> > On Monday 30 August 2010, Alan Cox wrote:
>> >> > My impression was that it should actually be converted into an hvc
>> >> > driver as a cleanup and moved to drivers/tty/hvc. It can probably
>> >> > get reduced to one third of its size if you do that.
>> >>
>> >> Not sure it makes sense - hvc seems the wrong abstraction.
>> >
>> > It seems to be very similar to hvc_tile.c in purpose, which is
>> > the most trivial driver we have. Why would that not work?
>> >
>> > Most of bfin_jtag_comm is about interfacing with the tty layer
>> > and providing a kernel thread to do the polling, which is exactly
>> > what hvc_console.c does.
>>
>> i have no idea what "hvc" is, but my limited knowledge was that it was
>> for large powerpc servers, so i didnt bother looking at it too much.
>> i simply wanted a way to create a tty on top of the hardware channel.
>> if there is a framework that doesnt break this usage and lets me
>> simplify my driver, then either works for me.
>
> HVC started out as the console for large powerpc, but has turned into
> a generic framework for TTY drivers that are based on simple read/write
> operations with or without interrupts.
>
> Please take a look at drivers/char/hvc_tile.c, which was added recently
> for a scenario quite similar to yours (debug port, not irq).

will do, thanks
-mike