Re: [PATCH v2 2/6] iio: light: stk3310: Implement vdd supply and power it off during suspend

Jonathan Cameron
2024-04-28T16:34:54Z

On Wed, 24 Apr 2024 02:16:06 +0300
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Wed, Apr 24, 2024 at 1:41 AM Aren Moynihan <aren@peacevolution.org> wrote:
> >
> > From: Ondrej Jirman <megi@xff.cz>
> >
> > VDD power input can be used to completely power off the chip during
> > system suspend. Do so if available.
>
> ...
>
> > ret = stk3310_init(indio_dev);
> > if (ret < 0)
> > - return ret;
> > + goto err_vdd_disable;
>
> This is wrong. You will have the regulator being disabled _before_
> IRQ. Note, that the original code likely has a bug which sets states
> before disabling IRQ and removing a handler.
>
> Side note, you may make the driver neater with help of
>
> struct device *dev = &client->dev;
>
> defined in this patch.
>
> ...
>
> > static int stk3310_suspend(struct device *dev)
> > {
> > struct stk3310_data *data;
>
> > data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
>
> Side note: This may be updated (in a separate change) to use
> dev_get_drvdata() directly.
>
> Jonathan, do we have something like iio_priv_from_drvdata(struct
> device *dev)? Seems many drivers may utilise it.

Not yet, but I'm not sure it's a good idea as there is no inherent
reason to assume the drvdata is a struct iio_dev. It often is but
adding a function that assumes that is a path to subtle bugs.

Jonathan

>
> > }
>
> ...
>
> > static int stk3310_resume(struct device *dev)
>
> Ditto.
>
> --
> With Best Regards,
> Andy Shevchenko