RE: [PATCH v3 3/3] eeprom: at24: enable runtime pm support

From: Mohandass, Divagar
Date: Wed Aug 30 2017 - 13:07:36 EST


Hi Sakari,

Thanks for the review.
My comments below.

---
^Divagar

>-----Original Message-----
>From: Sakari Ailus [mailto:sakari.ailus@xxxxxx]
>Sent: Wednesday, August 30, 2017 6:11 PM
>To: Mohandass, Divagar <divagar.mohandass@xxxxxxxxx>
>Cc: robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; wsa@xxxxxxxxxxxxx;
>devicetree@xxxxxxxxxxxxxxx; linux-i2c@xxxxxxxxxxxxxxx; linux-
>kernel@xxxxxxxxxxxxxxx; Mani, Rajmohan <rajmohan.mani@xxxxxxxxx>
>Subject: Re: [PATCH v3 3/3] eeprom: at24: enable runtime pm support
>
>On Wed, Aug 30, 2017 at 12:32:07PM +0000, Mohandass, Divagar wrote:
>> >> @@ -743,6 +770,15 @@ static int at24_probe(struct i2c_client
>> >> *client, const struct i2c_device_id *id)
>> >>
>> >> i2c_set_clientdata(client, at24);
>> >>
>> >> + /* enable runtime pm */
>> >> + pm_runtime_get_noresume(&client->dev);
>> >> + err = pm_runtime_set_active(&client->dev);
>> >> + if (err < 0)
>> >> + goto err_clients;
>> >> +
>> >> + pm_runtime_enable(&client->dev);
>> >> + pm_runtime_put(&client->dev);
>> >> +
>> >
>> >You're just about to perform a read here. I believe you should move
>> >the last put after that.
>>
>> At the end of at24_read we are performing a pm_runtime_put, still we need
>this change ?
>
>True, so this isn't an actual problem.
>
>It'll still power the chip down when you're about to need it, so it'd make sense
>to perform the check before pm_runtime_put().
>
>I might move the runtime PM setup after the check altogether.

Ok, I will move the pm_runtime_put() after the check and publish the v4.
Moving the PM setup altogether below, will introduce more error handling in read call.

>
>--
>Sakari Ailus
>e-mail: sakari.ailus@xxxxxx