Re: [PATCH v2 3/8] iio: at91_adc: pass ref to IIO device via param for int function

Jonathan Cameron
2020-05-16T17:17:56Z

On Thu, 14 May 2020 16:17:05 +0300
Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:

> Since there will be some changes to how iio_priv_to_dev() is implemented,
> it could be that the helper becomes a bit slower, as it will be hidden away
> in the IIO core.
>
> For this driver, the IIO device can be passed directly as a parameter to
> the at91_ts_sample() function, thus making it immune to the change of
> iio_priv_to_dev().
> The function gets called in an interrupt context.
>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
I wonder. Should we just pass the struct device? It's only used for
error printing I think, so we could make that explicit.

I'm not that bothered either way though.

Jonathan

> ---
> drivers/iio/adc/at91_adc.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index 0368b6dc6d60..5999defe47cd 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -287,13 +287,12 @@ static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
> }
> }
>
> -static int at91_ts_sample(struct at91_adc_state *st)
> +static int at91_ts_sample(struct iio_dev *idev, struct at91_adc_state *st)
> {
> unsigned int xscale, yscale, reg, z1, z2;
> unsigned int x, y, pres, xpos, ypos;
> unsigned int rxp = 1;
> unsigned int factor = 1000;
> - struct iio_dev *idev = iio_priv_to_dev(st);
>
> unsigned int xyz_mask_bits = st->res;
> unsigned int xyz_mask = (1 << xyz_mask_bits) - 1;
> @@ -449,7 +448,7 @@ static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private)
>
> if (status & AT91_ADC_ISR_PENS) {
> /* validate data by pen contact */
> - at91_ts_sample(st);
> + at91_ts_sample(idev, st);
> } else {
> /* triggered by event that is no pen contact, just read
> * them to clean the interrupt and discard all.