Re: [PATCH] iio: light: gp2ap002: Take runtime PM reference on light read

[Jonathan Cameron <jic23@kernel.org>]

On Fri,  8 May 2020 18:42:21 -0700
Jonathan Bakker <xc-racer2@live.ca> wrote:

> The light sensor needs the regulators to be enabled which means
> the runtime PM needs to be on.  This only happened when the
> proximity part of the chip was enabled.
> 
> As fallout from this change, only report changes to the prox
> state in the interrupt handler when it is explicitly enabled.
> 
> Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Looks good to me, but needs a fixes tag as we'll want to fix
this up in all kernels where it applies (just the current
RCs I think..)

Thanks,

Jonathan

> ---
>  drivers/iio/light/gp2ap002.c | 19 ++++++++++++++++---
>  1 file changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/light/gp2ap002.c b/drivers/iio/light/gp2ap002.c
> index b7ef16b28280..7a2679bdc987 100644
> --- a/drivers/iio/light/gp2ap002.c
> +++ b/drivers/iio/light/gp2ap002.c
> @@ -158,6 +158,9 @@ static irqreturn_t gp2ap002_prox_irq(int irq, void *d)
>  	int val;
>  	int ret;
>  
> +	if (!gp2ap002->enabled)
> +		goto err_retrig;
> +
>  	ret = regmap_read(gp2ap002->map, GP2AP002_PROX, &val);
>  	if (ret) {
>  		dev_err(gp2ap002->dev, "error reading proximity\n");
> @@ -247,6 +250,8 @@ static int gp2ap002_read_raw(struct iio_dev *indio_dev,
>  	struct gp2ap002 *gp2ap002 = iio_priv(indio_dev);
>  	int ret;
>  
> +	pm_runtime_get_sync(gp2ap002->dev);
> +
>  	switch (mask) {
>  	case IIO_CHAN_INFO_RAW:
>  		switch (chan->type) {
> @@ -255,13 +260,21 @@ static int gp2ap002_read_raw(struct iio_dev *indio_dev,
>  			if (ret < 0)
>  				return ret;
>  			*val = ret;
> -			return IIO_VAL_INT;
> +			ret = IIO_VAL_INT;
> +			goto out;
>  		default:
> -			return -EINVAL;
> +			ret = -EINVAL;
> +			goto out;
>  		}
>  	default:
> -		return -EINVAL;
> +		ret = -EINVAL;
>  	}
> +
> +out:
> +	pm_runtime_mark_last_busy(gp2ap002->dev);
> +	pm_runtime_put_autosuspend(gp2ap002->dev);
> +
> +	return ret;
>  }
>  
>  static int gp2ap002_init(struct gp2ap002 *gp2ap002)