Re: [PATCH 4/4] mfd: 88pm800: allocate pdata->rtc if not allocated earlier

[Vaibhav Hiremath]

On Tuesday 02 June 2015 01:10 PM, Lee Jones wrote:
> On Tue, 02 Jun 2015, Vaibhav Hiremath wrote:
> > On Monday 01 June 2015 01:52 PM, Lee Jones wrote:
> > > On Sat, 30 May 2015, Vaibhav Hiremath wrote:
> > >
> > > > RTC in pmic 88PM800 can run even the core is powered off, and user
> > > > can set alarm in RTC. When the alarm is timed out, the PMIC will power up
> > > > the core, and the whole system will boot up. And during PMIC driver probe,
> > > > it will read some register to find out whether this boot is caused by RTC
> > > > timeout or not, and pass on this information to the RTC driver.
> > > >
> > > > So we need rtc platform data to be existed in PMIC driver to pass this
> > > > information.
> > > >
> > > > Signed-off-by: Chao Xie <chao.xie@xxxxxxxxxxx>
> > > > Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@xxxxxxxxxx>
> > > > ---
> > > >   drivers/mfd/88pm800.c | 19 +++++++++++++++++++
> > > >   1 file changed, 19 insertions(+)
> > > >
> > > > diff --git a/drivers/mfd/88pm800.c b/drivers/mfd/88pm800.c
> > > > index 8ea4467..34546a1 100644
> > > > --- a/drivers/mfd/88pm800.c
> > > > +++ b/drivers/mfd/88pm800.c
> > > > @@ -586,6 +586,25 @@ static int pm800_probe(struct i2c_client *client,
> > > >   			return ret;
> > > >   	}
> > > >
> > > > +	/*
> > > > +	 * RTC in pmic can run even the core is powered off, and user can set
> > > > +	 * alarm in RTC. When the alarm is time out, the PMIC will power up
> > > > +	 * the core, and the whole system will boot up. When PMIC driver is
> > > > +	 * probed, it will read out some register to find out whether this
> > > > +	 * boot is caused by RTC timeout or not, and it need pass this
> > > > +	 * information to RTC driver.
> > > > +	 * So we need rtc platform data to be existed to pass this information.
> > > > +	 */
> > > > +	if (!pdata->rtc) {
> > > > +		pdata->rtc = devm_kzalloc(&client->dev,
> > > > +					  sizeof(*(pdata->rtc)), GFP_KERNEL);
> > > > +		if (!pdata->rtc) {
> > > > +			dev_err(&client->dev,
> > > > +					"failed to allocate memory for rtc\n");
> > > > +			return -ENOMEM;
> > > > +		}
> > > > +	}
> > > > +
> > >
> > > Where is this memory first used?
> >
> > In the same file, look for field "rtc_wakeup".
> >
> > FYI,
> >
> > This field is used in two files,
> >
> > drivers/mfd/88pm800.c
> > and
> > drivers/rtc/rtc-88pm800.c	[sets the "platform_data" field]
>
> Then were is the platform_data field subsequently used?


Currently not used, but it is for future use, where we would be
interested to know that the wakeup is really from reset or RTC wakeup.

> Looking at the RTC platform data declaration I see:
>
> struct pm80x_rtc_pdata {
>      int             vrtc;
>      int             rtc_wakeup;
> };
>
> Is 'vrtc' even used?  If so, where?


No, it is not.

Thanks,
Vaibhav
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