Re: should RTS init in serial core be tied to CRTSCTS

From: Robin Getz
Date: Sun Mar 04 2007 - 15:41:51 EST


On Sun 4 Mar 2007 14:46, Russell King pondered:
> On Thu, Mar 01, 2007 at 07:03:02PM -0500, Mike Frysinger wrote:
> > the console= bootcmd allows for controlling of the initial state of
> > flow control by adding/omitting the 'r' suffix ...
>
> The console command *only* sets the state for the kernel's use of one
> serial port. It does not affect any other serial port, so tying
> random RTS behaviours into that command line option is absolutely
> silly.

I have one serial port in the system, it shares console, and the
communications port for the application. (But I guess that is besides the
point).

When the common serial core initialises the UART, and sees that it has the
capability to do HW flow control - it enables it, asserting the pin, even if
I don't want it at that moment in time.

The real issue is that there is some legacy equipment, which gets confused if
it sees glitches on RTS (which happens today, when serial core init asserts
RTS, and then the the main application turns it off)...

How do I set the set up the UART, so RTS is avaliable, but not enabled?

Thanks
-Robin
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