On Wed, 1 Sep 2010 01:12:11 +0200, Rafael J. Wysocki wrote:
> On Tuesday, August 31, 2010, Mark Brown wrote:
> > On Mon, Aug 30, 2010 at 11:43:23AM -0700, Kevin Hilman wrote:
> > > Vishwanath BS <[email protected]> writes:
> > >
> > > > In current i2c core driver, pm_runtime_set_active call from
> > > > i2c_device_pm_resume
> > > > is not balanced by pm_runtime_set_suspended call from
> > > > i2c_device_pm_suspend.
> > > > pm_runtime_set_active called from resume path will increase the
> > > > child_count of
> > > > the device's parent. However, matching pm_runtime_set_suspended is not
> > > > called
> > > > in suspend routine because of which child_count of the device's parent
> > > > is not balanced, preventing the parent device to idle.
> > > > Issue has been fixed by adding pm_runtime_set_suspended call inside
> > > > suspend
> > > > reoutine which will make sure that child_counts are balanced.
> > > > This fix has been tested on OMAP4430.
> > > >
> > > > Signed-off-by: Partha Basak <[email protected]>
> > > > Signed-off-by: Vishwanath BS <[email protected]>
> > > >
> > > > Cc: Rafael J. Wysocki <[email protected]>
> > > > Cc: Kevin Hilman <[email protected]>
> > > > Cc: Ben Dooks <[email protected]>
> > >
> > > Also Cc'ing Mark Brown as original author of runtime PM for i2-core.
> >
> > Also Jean Delvare who maintains the I2C core. To be honest Rafael did
> > all the actual work here (and has since rewritten the code anyway).
>
> Sorry for the delay.
>
> The fix looks reasonable to me.
I take this as an Acked-by. Patch applied, thanks.
>
> > > > ---
> > > > drivers/i2c/i2c-core.c | 12 ++++++++++--
> > > > 1 files changed, 10 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
> > > > index 6649176..3146bff
> > > > --- a/drivers/i2c/i2c-core.c
> > > > +++ b/drivers/i2c/i2c-core.c
> > > > @@ -196,14 +196,22 @@ static int i2c_legacy_resume(struct device *dev)
> > > > static int i2c_device_pm_suspend(struct device *dev)
> > > > {
> > > > const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm :
> > > > NULL;
> > > > + int ret;
> > > >
> > > > if (pm_runtime_suspended(dev))
> > > > return 0;
> > > >
> > > > if (pm)
> > > > - return pm->suspend ? pm->suspend(dev) : 0;
> > > > + ret = pm->suspend ? pm->suspend(dev) : 0;
> > > > + else
> > > > + ret = i2c_legacy_suspend(dev, PMSG_SUSPEND);
> > > >
> > > > - return i2c_legacy_suspend(dev, PMSG_SUSPEND);
> > > > + if (!ret) {
> > > > + pm_runtime_disable(dev);
> > > > + pm_runtime_set_suspended(dev);
> > > > + pm_runtime_enable(dev);
> > > > + }
> > > > + return ret;
> > > > }
> > > >
> > > > static int i2c_device_pm_resume(struct device *dev)
> >
> >
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Jean Delvare
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
