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[RFC] pxa serial driver, updated modem control line handling

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Hi,
i've posted a problem with the pxa serial driver's modem control line handling 
during suspend cycles to the LKML. It's about RTS being reasserted just 
before going to sleep:

http://marc.theaimsgroup.com/?l=linux-kernel&m=114606462816406&w=2
> When suspending (e.g. apm --suspend) a machine, the serial_core suspend
> code tries to disable modem control lines (including RTS):
>http://sosdg.org/~coywolf/lxr/source/drivers/serial/serial_core.c?v=2.6;a=arm#L1926
> This is needed to stop the other side of a serial link from sending 
> any data after our serial port has been disabled.
>
> Now in line 1937 ops->shutdown(port) is called. For 8250 this points to
> serial8250_shutdown, for pxa to serial_pxa_shutdown. Both call
> xxx__set_mctrl(&up->port, up->port.mctrl) which will restore the old
> control line values and reverse the intended effect.

And, as I didn't get any responses i prepared a patch:
http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=3498/1

Is this patch the way to go? How else could the problem be approached?

Thanks for your comments
Uli


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