Re: [PATCH v8 2/8] iio: dac: ad5686: missing NULL check on match data

On Fri, 17 Jul 2026 13:28:52 +0300
Andy Shevchenko <[email protected]> wrote:

> On Fri, Jul 17, 2026 at 10:31:26AM +0100, Rodrigo Alencar wrote:
> > On 17/07/26 11:15, Andy Shevchenko wrote:  
> > > On Fri, Jul 17, 2026 at 07:51:35AM +0100, Rodrigo Alencar wrote:  
> > > > On 16/07/26 21:42, Andy Shevchenko wrote:  
> > > > > On Thu, Jul 16, 2026 at 01:14:18PM +0100, Rodrigo Alencar via B4 Relay wrote:  
> 
> ...
> 
> > > > > >  	struct iio_dev *indio_dev;
> > > > > >  	int ret, i;  
> > > > > 
> > > > > Move an assignment here as well.
> > > > > 
> > > > > 	chip_info = ...  
> > > > 
> > > > assignment? this is an input param validation  
> > > 
> > > Can we make sure we always get a correct one to begin with?
> > > With that an assignment and check can be coupled together.
> > > Also consider use -ENODATA as it's most likely comes from
> > > driver_data.  
> > 
> > I suppose you are suggesting to move the check to the bus code with:
> > 
> > 	info = i2c_get_match_data(i2c);
> > 	if (!info)
> > 		return -ENODATA;
> > 
> > rather than here in the core/common code.  
> 
> Yes! This avoids layering violation and makes the API contract cleaner.

I applied the following rather than going for a v9 for just this:
Shout if I messed it up.

diff --git a/drivers/iio/dac/ad5686-spi.c b/drivers/iio/dac/ad5686-spi.c
index 8abfaf8f0c46..591596a68004 100644
--- a/drivers/iio/dac/ad5686-spi.c
+++ b/drivers/iio/dac/ad5686-spi.c
@@ -98,8 +98,13 @@ static const struct ad5686_bus_ops ad5686_spi_ops = {
 
 static int ad5686_spi_probe(struct spi_device *spi)
 {
-       return ad5686_probe(&spi->dev, spi_get_device_match_data(spi),
-                           spi->modalias, &ad5686_spi_ops);
+       const struct ad5686_chip_info *chip_info;
+
+       chip_info = spi_get_device_match_data(spi);
+       if (!chip_info)
+               return -ENODEV;
+
+       return ad5686_probe(&spi->dev, chip_info, spi->modalias, &ad5686_spi_ops);
 }
 
 static const struct spi_device_id ad5686_spi_id[] = {
diff --git a/drivers/iio/dac/ad5696-i2c.c b/drivers/iio/dac/ad5696-i2c.c
index d49946adbde3..a6c85d0c33c9 100644
--- a/drivers/iio/dac/ad5696-i2c.c
+++ b/drivers/iio/dac/ad5696-i2c.c
@@ -68,8 +68,13 @@ static const struct ad5686_bus_ops ad5686_i2c_ops = {
 
 static int ad5686_i2c_probe(struct i2c_client *i2c)
 {
-       return ad5686_probe(&i2c->dev, i2c_get_match_data(i2c),
-                           i2c->name, &ad5686_i2c_ops);
+       const struct ad5686_chip_info *chip_info;
+
+       chip_info = i2c_get_match_data(i2c);
+       if (!chip_info)
+               return -ENODEV;
+
+       return ad5686_probe(&i2c->dev, chip_info, i2c->name, &ad5686_i2c_ops);
 }


> 
> > > > > > +	if (!chip_info)
> > > > > > +		return -ENODEV;  
>