Re: [PATCH 11/16] iio: adc: max1027: Separate the IRQ handler from the read logic

From: Jonathan Cameron <jic23@kernel.org>
To: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: "Sa, Nuno" <Nuno.Sa@analog.com>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	"linux-iio@vger.kernel.org" <linux-iio@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 11/16] iio: adc: max1027: Separate the IRQ handler from the read logic
Date: Sat, 4 Sep 2021 15:08:34 +0100	[thread overview]
Message-ID: <20210904150834.7002f023@jic23-huawei> (raw)
In-Reply-To: <20210902105519.5891a90f@xps13>

On Thu, 2 Sep 2021 10:55:19 +0200
Miquel Raynal <miquel.raynal@bootlin.com> wrote:

> Hi Nuno,
> 
> "Sa, Nuno" <Nuno.Sa@analog.com> wrote on Fri, 20 Aug 2021 07:23:33
> +0000:
> 
> > > -----Original Message-----
> > > From: Miquel Raynal <miquel.raynal@bootlin.com>
> > > Sent: Wednesday, August 18, 2021 1:12 PM
> > > To: Jonathan Cameron <jic23@kernel.org>; Lars-Peter Clausen
> > > <lars@metafoo.de>
> > > Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>; linux-
> > > iio@vger.kernel.org; linux-kernel@vger.kernel.org; Miquel Raynal
> > > <miquel.raynal@bootlin.com>
> > > Subject: [PATCH 11/16] iio: adc: max1027: Separate the IRQ handler
> > > from the read logic
> > > 
> > > [External]
> > > 
> > > Create a max1027_read_scan() helper which will make clearer the
> > > future IRQ
> > > handler updates (no functional change).
> > > 
> > > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> > > ---
> > >  drivers/iio/adc/max1027.c | 27 +++++++++++++++++++++------
> > >  1 file changed, 21 insertions(+), 6 deletions(-)
> > > 
> > > diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
> > > index 83526f3d7d3a..afc3ce69f7ea 100644
> > > --- a/drivers/iio/adc/max1027.c
> > > +++ b/drivers/iio/adc/max1027.c
> > > @@ -427,19 +427,18 @@ static int
> > > max1027_set_cnvst_trigger_state(struct iio_trigger *trig, bool state)
> > >  	return 0;
> > >  }
> > > 
> > > -static irqreturn_t max1027_trigger_handler(int irq, void *private)
> > > +static int max1027_read_scan(struct iio_dev *indio_dev)
> > >  {
> > > -	struct iio_poll_func *pf = private;
> > > -	struct iio_dev *indio_dev = pf->indio_dev;
> > >  	struct max1027_state *st = iio_priv(indio_dev);
> > >  	unsigned int scanned_chans = fls(*indio_dev-    
> > > >active_scan_mask);    
> > >  	u16 *buf = st->buffer;
> > >  	unsigned int bit;
> > > -
> > > -	pr_debug("%s(irq=%d, private=0x%p)\n", __func__, irq,
> > > private);
> > > +	int ret;
> > > 
> > >  	/* fill buffer with all channel */
> > > -	spi_read(st->spi, st->buffer, scanned_chans * 2);
> > > +	ret = spi_read(st->spi, st->buffer, scanned_chans * 2);
> > > +	if (ret < 0)
> > > +		return ret;
> > > 
> > >  	/* Only keep the channels selected by the user */
> > >  	for_each_set_bit(bit, indio_dev->active_scan_mask,
> > > @@ -451,6 +450,22 @@ static irqreturn_t max1027_trigger_handler(int
> > > irq, void *private)
> > > 
> > >  	iio_push_to_buffers(indio_dev, st->buffer);
> > > 
> > > +	return 0;
> > > +}
> > > +
> > > +static irqreturn_t max1027_trigger_handler(int irq, void *private)
> > > +{
> > > +	struct iio_poll_func *pf = private;
> > > +	struct iio_dev *indio_dev = pf->indio_dev;
> > > +	int ret;
> > > +
> > > +	pr_debug("%s(irq=%d, private=0x%p)\n", __func__, irq,
> > > private);
> > > +    
> > 
> > This should be more consistent... use 'dev_err()'. I would also
> > argue to use the spi dev as the driver state structure holds a
> > pointer to it...  
> 
> I honestly don't see the point of these debug messages (there is
> another useless pr_debug in probe). I kept it here as I am just moving
> code around without any changes, but if you don't like it (me neither)
> I'll add a simple patch dropping them.
Go for it :)

> 
> Thanks,
> Miquèl