[PATCHv8 00/23]I2C big cleanup

Kevin Hilman khilman at deeprootsystems.com
Thu Sep 13 17:28:02 EDT 2012


Felipe Balbi <balbi at ti.com> writes:

> Hi,
>
> On Thu, Sep 13, 2012 at 11:04:42AM -0700, Kevin Hilman wrote:
>> Kevin Hilman <khilman at deeprootsystems.com> writes:
>> 
>> > Kevin Hilman <khilman at deeprootsystems.com> writes:
>> >
>> [...]
>> 
>> >> Sorry to be late to the party (again), but still catching up after some
>> >> time off.
>> >>
>> >> Unfortunately, this series causes PM regressions on several OMAP
>> >> platforms.  I hope we can hold off on this until those issues are
>> >> addressed.
>> >
>> > I tracked the regression down to [PATCHv8 21/22] (see reply there.)
>> >
>> > Since this series is already merged, I suggest that the problem patch be
>> > reverted, at least for v3.7 and until the problem is better understood
>> > and tested.
>> >
>> > With that patch reverted, all my PM tests are passing.  Feel free to
>> > add:
>> 
>> OK, the i2c series is off the hook.
>> 
>> Felipe and I spent a little time tracking this down.  Felipe suggested
>> that there might be a driver with periodic i2c activity keeping I2C
>> awake, and thus preventing CORE retention.  He was right.
>
> FYI, the original idea came from Shubhro. We agreed that would be the
> only way i2c would be prevented from idling.

Great, thanks Shubhro!

Also, FYI, I just submitted a patch to the TWL RTC driver which was the
source of all the I2C activity since it's on the I2C-connected PMIC.

Thanks for the help and suggestions,

Kevin

[1] https://groups.google.com/forum/#!topic/rtc-linux/sFbYmAzCRLQ



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