[PATCH 4/4] mfd: 88pm800: allocate pdata->rtc if not allocated earlier
Vaibhav Hiremath
vaibhav.hiremath at linaro.org
Tue Jun 2 02:05:58 PDT 2015
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 at marvell.com>
>>>> Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath at linaro.org>
>>>> ---
>>>> 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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