Re: [PATCH] serial: DCC(JTAG) serial and console emulation support

[Daniel Walker]

On Thu, 2010-10-07 at 21:50 +0100, Alan Cox wrote:
> > +	  Say Y here if you want to install DCC driver as a normal serial port
> > +	  /dev/ttyS0 (major 4, minor 64). Otherwise, it appears as /dev/ttyJ0
> > +	  (major 4, minor 128) and can co-exist with other UARTs, such as
> > +	  8250/16C550 compatibles.
> > +
> 
> NAK to both

Both what?

> ttyJ0 is 204,186 for "JTAG1 DCC protocol based serial"
> 
> so there is an existing name and minor allocation, which as you won't be
> using two of them should be quite usable.
> 
> If you want to be able to switch at runtime to pretend it is ttyS0 please
> deal with that in your user space. The same rules apply to you as have
> been applied to everyone else who has tried to implement this same crap
> in their uart driver too (we'd have it in about 30 by now otherwise)

I would agree if this wasn't strictly for debugging embedded devices in
difficult situations.. After talking to Mike, it's seems like it would
be useful to have this as a ttyS* specifically because embedded devices
won't always create a ttyJ* for you and ttyS* will likely already exist.

Daniel

-- 

Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/