Re: [PATCH] iio: at91_adc: remove usage of iio_priv_to_dev() helper

[Ardelean, Alexandru]

On Sun, 2020-05-31 at 15:42 +0100, Jonathan Cameron wrote:
> [External]
> 
> On Mon, 25 May 2020 13:25:13 +0300
> Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:
> 
> > We may want to get rid of the iio_priv_to_dev() helper. The reason is
> > that
> > we will hide some of the members of the iio_dev structure (to prevent
> > drivers from accessing them directly), and that will also mean hiding
> > the
> > implementation of the iio_priv_to_dev() helper inside the IIO core.
> > 
> > Hiding the implementation of iio_priv_to_dev() implies that some fast-
> > paths
> > may not be fast anymore, so a general idea is to try to get rid of the
> > iio_priv_to_dev() altogether.
> > The iio_priv() helper won't be affected by the rework, as the iio_dev
> > struct will keep a reference to the private information.
> > 
> > For this driver, not using iio_priv_to_dev(), means reworking some
> > paths to
> > pass the iio device and using iio_priv() to access the private
> > information.
> > 
> > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> Looks good to me.  Will leave it a bit longer though to potentially
> get some people more familiar with the driver to sanity check it.
> 
> Poke me after the usual couple of weeks if I seem to have lost it
> down the back of the sofa.
> 

ping on this

> Thanks,
> 
> Jonathan
> 
> > ---
> >  drivers/iio/adc/at91_adc.c | 30 +++++++++++++++---------------
> >  1 file changed, 15 insertions(+), 15 deletions(-)
> > 
> > diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> > index 0368b6dc6d60..896af58e88bc 100644
> > --- a/drivers/iio/adc/at91_adc.c
> > +++ b/drivers/iio/adc/at91_adc.c
> > @@ -287,13 +287,13 @@ 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 = iio_priv(idev);
> >  	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 +449,7 @@ 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);
> >  		} else {
> >  			/* triggered by event that is no pen contact, just
> > read
> >  			 * them to clean the interrupt and discard all.
> > @@ -737,10 +737,10 @@ static int at91_adc_read_raw(struct iio_dev
> > *idev,
> >  	return -EINVAL;
> >  }
> >  
> > -static int at91_adc_of_get_resolution(struct at91_adc_state *st,
> > +static int at91_adc_of_get_resolution(struct iio_dev *idev,
> >  				      struct platform_device *pdev)
> >  {
> > -	struct iio_dev *idev = iio_priv_to_dev(st);
> > +	struct at91_adc_state *st = iio_priv(idev);
> >  	struct device_node *np = pdev->dev.of_node;
> >  	int count, i, ret = 0;
> >  	char *res_name, *s;
> > @@ -866,10 +866,10 @@ static int at91_adc_probe_dt_ts(struct
> > device_node *node,
> >  	}
> >  }
> >  
> > -static int at91_adc_probe_dt(struct at91_adc_state *st,
> > +static int at91_adc_probe_dt(struct iio_dev *idev,
> >  			     struct platform_device *pdev)
> >  {
> > -	struct iio_dev *idev = iio_priv_to_dev(st);
> > +	struct at91_adc_state *st = iio_priv(idev);
> >  	struct device_node *node = pdev->dev.of_node;
> >  	struct device_node *trig_node;
> >  	int i = 0, ret;
> > @@ -910,7 +910,7 @@ static int at91_adc_probe_dt(struct at91_adc_state
> > *st,
> >  	}
> >  	st->vref_mv = prop;
> >  
> > -	ret = at91_adc_of_get_resolution(st, pdev);
> > +	ret = at91_adc_of_get_resolution(idev, pdev);
> >  	if (ret)
> >  		goto error_ret;
> >  
> > @@ -1010,9 +1010,9 @@ static void atmel_ts_close(struct input_dev *dev)
> >  		at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN);
> >  }
> >  
> > -static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz)
> > +static int at91_ts_hw_init(struct iio_dev *idev, u32 adc_clk_khz)
> >  {
> > -	struct iio_dev *idev = iio_priv_to_dev(st);
> > +	struct at91_adc_state *st = iio_priv(idev);
> >  	u32 reg = 0;
> >  	u32 tssctim = 0;
> >  	int i = 0;
> > @@ -1085,11 +1085,11 @@ static int at91_ts_hw_init(struct
> > at91_adc_state *st, u32 adc_clk_khz)
> >  	return 0;
> >  }
> >  
> > -static int at91_ts_register(struct at91_adc_state *st,
> > +static int at91_ts_register(struct iio_dev *idev,
> >  		struct platform_device *pdev)
> >  {
> > +	struct at91_adc_state *st = iio_priv(idev);
> >  	struct input_dev *input;
> > -	struct iio_dev *idev = iio_priv_to_dev(st);
> >  	int ret;
> >  
> >  	input = input_allocate_device();
> > @@ -1161,7 +1161,7 @@ static int at91_adc_probe(struct platform_device
> > *pdev)
> >  	st = iio_priv(idev);
> >  
> >  	if (pdev->dev.of_node)
> > -		ret = at91_adc_probe_dt(st, pdev);
> > +		ret = at91_adc_probe_dt(idev, pdev);
> >  	else
> >  		ret = at91_adc_probe_pdata(st, pdev);
> >  
> > @@ -1301,11 +1301,11 @@ static int at91_adc_probe(struct
> > platform_device *pdev)
> >  			goto error_disable_adc_clk;
> >  		}
> >  	} else {
> > -		ret = at91_ts_register(st, pdev);
> > +		ret = at91_ts_register(idev, pdev);
> >  		if (ret)
> >  			goto error_disable_adc_clk;
> >  
> > -		at91_ts_hw_init(st, adc_clk_khz);
> > +		at91_ts_hw_init(idev, adc_clk_khz);
> >  	}
> >  
> >  	ret = iio_device_register(idev);