Re: [PATCH v2 08/16] iio: adc: sun4i-gpadc-iio: rework: add interrupt support

[Philipp Rossak]

On 31.01.2018 20:07, Quentin Schulz wrote:
> Hi Philipp,
>
> On Mon, Jan 29, 2018 at 12:29:11AM +0100, Philipp Rossak wrote:
> > This patch rewors the driver to support interrupts for the thermal part
> > of the sensor.
> >
> > This is only available for the newer sensor (currently H3 and A83T).
> > The interrupt will be trigerd on data available and triggers the update
> > for the thermal sensors. All newer sensors have different amount of
> > sensors and different interrupts for each device the reset of the
> > interrupts need to be done different
> >
> > For the newer sensors is the autosuspend disabled.
> >
> > Signed-off-by: Philipp Rossak <embed3d@xxxxxxxxx>
> > Acked-by: Jonathan  Cameron <jonathan.cameron@xxxxxxxxxx>
> > ---
> >   drivers/iio/adc/sun4i-gpadc-iio.c | 60 +++++++++++++++++++++++++++++++++++----
> >   include/linux/mfd/sun4i-gpadc.h   |  2 ++
> >   2 files changed, 56 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
> > index 74eeb5cd5218..b7b5451226b0 100644
> > --- a/drivers/iio/adc/sun4i-gpadc-iio.c
> > +++ b/drivers/iio/adc/sun4i-gpadc-iio.c
> > @@ -71,11 +71,14 @@ struct gpadc_data {
> >   	unsigned int	temp_data[MAX_SENSOR_COUNT];
> >   	int		(*sample_start)(struct sun4i_gpadc_iio *info);
> >   	int		(*sample_end)(struct sun4i_gpadc_iio *info);
> > +	u32		irq_clear_map;
> > +	u32		irq_control_map;
>
> I would say to use a regmap_irq_chip for controlling IRQs.
Sounds good for me! I will rework that in the next version.
> >   	bool		has_bus_clk;
> >   	bool		has_bus_rst;
> >   	bool		has_mod_clk;
> >   	int		sensor_count;
> >   	bool		supports_nvmem;
> > +	bool		support_irq;
> >   };
> >   
> >   static const struct gpadc_data sun4i_gpadc_data = {
> > @@ -90,6 +93,7 @@ static const struct gpadc_data sun4i_gpadc_data = {
> >   	.sample_end = sun4i_gpadc_sample_end,
> >   	.sensor_count = 1,
> >   	.supports_nvmem = false,
> > +	.support_irq = false,
>
> False is the default, no need to set support_irq.
>
> [...]
>
> >   struct sun4i_gpadc_iio {
> > @@ -332,6 +339,11 @@ static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val,
> >   		return 0;
> >   	}
> >   
> > +	if (info->data->support_irq) {
> > +		regmap_read(info->regmap, info->data->temp_data[sensor], val);
> > +		return 0;
> > +	}
> > +
>
> Maybe you could define a new thermal_zone_of_device_ops for these new
> thermal sensors? That way, you don't even need the boolean support_irq.
Sounds good for me! I will rework that in the next version.

> >   	return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq);
> >   }
> >   
> > @@ -429,6 +441,17 @@ static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id)
> >   	return IRQ_HANDLED;
> >   }
> >   
> > +static irqreturn_t sunxi_irq_thread(int irq, void *data)
>
> I think we're trying to avoid sunxi mentions but rather using the name
> of the first IP (in term of product release, not support) using this
> function.
>
> > +{
> > +	struct sun4i_gpadc_iio *info = data;
> > +
> > +	regmap_write(info->regmap, SUN8I_H3_THS_STAT, info->data->irq_clear_map);
> > +
>
> Will be handled by regmap_irq_chip.
> [...]
> > -	info->no_irq = true;
> > +	if (info->data->support_irq) {
> > +		/* only the new versions of ths support right now irqs */
> > +		irq = platform_get_irq(pdev, 0);
> > +		if (irq < 0) {
> > +			dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
> > +			return irq;
> > +		}
> > +
> > +		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
> > +				sunxi_irq_thread, IRQF_ONESHOT,
> > +				dev_name(&pdev->dev), info);
> > +		if (ret)
> > +			return ret;
> > +
> > +	} else
> > +		info->no_irq = true;
> > +
>
> That's a bit funny to have two booleans named no_irq and support_irq :)
I know this looks very funny. I thought this would be better to keep, to 
_not_ break anything. Since I will rework the whole driver and integrate 
the mfd part I hope I can remove both.

> >   	indio_dev->num_channels = ARRAY_SIZE(sun8i_a33_gpadc_channels);
> >   	indio_dev->channels = sun8i_a33_gpadc_channels;
> >   
> > @@ -789,11 +829,13 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
> >   	if (ret)
> >   		return ret;
> >   
> > -	pm_runtime_set_autosuspend_delay(&pdev->dev,
> > -					 SUN4I_GPADC_AUTOSUSPEND_DELAY);
> > -	pm_runtime_use_autosuspend(&pdev->dev);
> > -	pm_runtime_set_suspended(&pdev->dev);
> > -	pm_runtime_enable(&pdev->dev);
> > +	if (!info->data->support_irq) {
> > +		pm_runtime_set_autosuspend_delay(&pdev->dev,
> > +						 SUN4I_GPADC_AUTOSUSPEND_DELAY);
> > +		pm_runtime_use_autosuspend(&pdev->dev);
> > +		pm_runtime_set_suspended(&pdev->dev);
> > +		pm_runtime_enable(&pdev->dev);
> > +	}
>
> Why would you not want your IP to do runtime PM?

I will enable this again, in the next version! I had some issues with 
this, thus I disabled this, but I know now what I did wrong!

Thanks,
Philipp