[PATCH] Watchdog: OMAP: Fix the runtime pm code to avoid module getting stuck intransition state.

[santosh.shilimkar@ti.com (Shilimkar, Santosh)]

Wim,

On Mon, Jun 18, 2012 at 11:11 AM, Shilimkar, Santosh
<santosh.shilimkar@ti.com> wrote:
> (You should cc linux-omap too.  CC'ing linux-omap)
>
> On Mon, Jun 18, 2012 at 10:53 AM, Lokesh Vutla <lokeshvutla@ti.com> wrote:
>> OMAP watchdong driver is adapted to runtime PM like a general device
>> driver but it is not appropriate. It is causing couple of functional
>> issues.
>>
>> 1. On OMAP4 SYSCLK can't be gated, because of issue with WDTIMER2 module,
>> which constantly stays in "in transition" state. Value of register
>> CM_WKUP_WDTIMER2_CLKCTRL is always 0x00010000 in this case.
>> Issue occurs immediately after first idle, when hwmod framework tries
>> to disable WDTIMER2 functional clock - "wd_timer2_fck". After this
>> module falls to "in transition" state, and SYSCLK gating is blocked.
>>
>> 2. Due to runtime PM, watchdog timer may be completely disabled.
>> In current code base watchdog timer is not disabled only because of
>> issue 1. Otherwise state of WDTIMER2 module will be "Disabled", and there
>> will be no interrupts from omap_wdt. In other words watchdog will not
>> work at all.
>>
>> Watchdong is a special IP and it should not be disabled otherwise
>> purpose of it itself is defeated. Watchdog functional clock should
>> never be disabled. This patch updates the runtime PM handling in
>> driver so that runtime PM is limited only during probe/shutdown
>> and suspend/resume.
>>
>> The patch fixes issue 1 and 2
>>
>> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
>> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
>> Cc: Wim Van Sebroeck <wim@iguana.be>
>> ---

Any comments on this patch ? If not, can you please
queue this up for the 3.5-rc?

Regards
Santosh