[PATCH v2] iio: adc: stm32: fix null pointer on defer_probe error

[Jonathan Cameron]

On Mon, 22 Nov 2021 14:45:01 +0000
Jonathan Cameron <Jonathan.Cameron at Huawei.com> wrote:

> On Mon, 22 Nov 2021 15:41:10 +0100
> Ahmad Fatoum <a.fatoum at pengutronix.de> wrote:
> 
> > On 22.11.21 15:38, Olivier Moysan wrote:  
> > > dev_err_probe() calls __device_set_deferred_probe_reason()
> > > on -EPROBE_DEFER error. If device pointer to driver core
> > > private structure is not initialized, an null pointer error occurs.
> > > This pointer is set on iio_device_register() call for iio device.
> > > 
> > > dev_err_probe() must be called with the device which is probing.
> > > Replace iio device by its parent device.
> > > 
> > > Fixes: 0e346b2cfa85 ("iio: adc: stm32-adc: add vrefint calibration support")
> > >   
> 
> I'll fix it when applying, but no blank line between Fixes tag and the others.
Applied to the fixes-togreg branch of iio.git.

I'll probably do a pull request later this week,

Jonathan

> 
> > > Signed-off-by: Olivier Moysan <olivier.moysan at foss.st.com>    
> > 
> > Reviewed-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
> >   
> > > ---
> > > Changes in v2:
> > > - Use parent device from indio_dev instead of private structure
> > > ---
> > >  drivers/iio/adc/stm32-adc.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
> > > index 7f1fb36c747c..341afdd342cc 100644
> > > --- a/drivers/iio/adc/stm32-adc.c
> > > +++ b/drivers/iio/adc/stm32-adc.c
> > > @@ -1986,7 +1986,7 @@ static int stm32_adc_populate_int_ch(struct iio_dev *indio_dev, const char *ch_n
> > >  			/* Get calibration data for vrefint channel */
> > >  			ret = nvmem_cell_read_u16(&indio_dev->dev, "vrefint", &vrefint);
> > >  			if (ret && ret != -ENOENT) {
> > > -				return dev_err_probe(&indio_dev->dev, ret,
> > > +				return dev_err_probe(indio_dev->dev.parent, ret,
> > >  						     "nvmem access error\n");
> > >  			}
> > >  			if (ret == -ENOENT)
> > >     
> > 
> >   
>