[PATCH 1/2] OMAP2+: UART: Fix incorrect population of default uart pads

[Raja, Govindraj]

On Tue, Apr 24, 2012 at 5:15 AM, Kevin Hilman <khilman at ti.com> wrote:
> "Govindraj.R" <govindraj.raja at ti.com> writes:
>
>> From: "Govindraj.R" <govindraj.raja at ti.com>
>>
>> The following commit:
>> (7496ba3  ARM: OMAP2+: UART: Add default mux for all uarts)
>> added default pads for all uarts. But not all boards tend to
>> use all uarts and most of unused uart pins are muxed for
>> other purpose. This commit breaks the modules which where trying
>> to use unused uart pins on their boards.
>>
>> So remove the default pads adding.
>
> I just noticed that this patch breaks runtime PM & wakeups for UART
> console (at least on 3530/Overo with ttyO2 console.)
>
> By removing the pads, the initial device_init_wakeup() is not called on
> port init.  Without this call serial_omap_pm() disables runtime PM
> because it checks device_may_wakeup().
>
> Since runtime PM was disabled, I manually re-enabled it and then enabled
> wakeups:
>
>  echo auto > /sys/devices/platform/omap_uart.2/power/control
>  echo enabled > /sys/devices/platform/omap_uart.2/tty/ttyO2/power/wakeup
>
> Then, after enabling auto-suspend timeouts, it seems wakeups are still
> not working since the console hangs.
>
> Reverting $SUBJECT patch gets things working again.

This was decided as part of discussion [1]

If we are _reconsidering_ taking this patch [2]
to dynamically probe uart pins and enable rx wakeup.

I can re-work on the patch[2] as per tony's comments[1]
and re-post it.

--
Thanks,
Govindraj.R

[1]:
http://www.spinics.net/lists/linux-omap/msg68226.html

[2]:
http://www.spinics.net/lists/linux-omap/msg67822.html