[PATCH v7 00/26] gpio/omap: driver cleanup and fixes

Kevin Hilman khilman at ti.com
Tue Sep 27 12:22:54 EDT 2011


"DebBarma, Tarun Kanti" <tarun.kanti at ti.com> writes:

> On Tue, Sep 27, 2011 at 4:40 AM, Kevin Hilman <khilman at ti.com> wrote:
>> "DebBarma, Tarun Kanti" <tarun.kanti at ti.com> writes:
>>
>> [...]
>>
>>> As pointed out by Kevin, debounce clock was not getting disabled.
>>> In my testing I was somehow grepping CORE power domain instead
>>> of PER power domain and hence missed it. The fix for the debounce
>>> clock issue is at the end of the email.
>>>
>>> - Have re-based the for_3.2/gpio-cleanup branch against 3.1-rc6.
>>> - Dropped [PATCH 26/26] gpio/omap: add dbclk aliases for all gpio modules
>>> as suggested by Kevin since it's already taken care by hwmod.
>>> - Added the debounce clock fix in the end.
>>
>> That debounce fix definitely makes things look better, but it's not
>> solving the problem...
>>
>>> With above, PER is hitting low power state in Suspend and Idle path.
>>>
>>> Have pushed a branch at below URL with mentioned changes.
>>> git://gitorious.org/omap-sw-develoment/linux-omap-dev.git
>>> for_3.2/kevin/gpio-cleanup
>>
>> I tested your branch on my 3430/n900 and PER is still not hitting
>> retention.  Setting all debounce values in the board file to zero using
>> the patch below[1] makes PER hit retention again.
>>
>> Assuming you don't have an n900 to test with, I suggest you just copy
>> the GPIO keys init from board-rx51-peripherals.c (or some of it) into
>> the board file you are testing with.
>>
>> The problem is most likely be related to having more than one GPIO in a
>> bank with debounce enabled, or more than one bank with GPIOs enabled and
>> your current test is not be catching it.
>>
> As per commit c8c9fda506945 {OMAP: PM: disable idle on suspend for
> GPIO and UART}, the gpio code needs to be fixed once GPIO driver is
> run-time adapted.  

Great, good catch.

> So I did below change as per the commit and now suspend is working
> fine even with board files change for debounce functionality. So the
> last series + below one line change is whats needed for suspend to
> work. Can you please see if this does help on your board ?

Yeah, with your patch, PER is hitting retention in suspend on my
3430/n900.

> I am not finished my idle testing yet but just reporting the suspend
> results.

For me, PER is not hitting retention on idle.

Also, your repost of v7 doesn't included any of the comments I made on
it yesterday.

Kevin



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