| Message ID | 20211118123952.15383-1-olivier.moysan@foss.st.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: adc: stm32: fix null pointer on defer_probe error | expand |
Hello Olivier, On 18.11.21 13:39, 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, > a null pointer error occurs. > This pointer is set too late on iio_device_register() call, for iio device. Even if it were set earlier, you should call dev_err_probe with the dev of the probe that's currently running. Not any other devices you created since then. > So use parent device instead for dev_err_probe() call. > > Fixes: 0e346b2cfa85 ("iio: adc: stm32-adc: add vrefint calibration support") > > Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com> > --- > drivers/iio/adc/stm32-adc.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c > index 7f1fb36c747c..14c7c9d390e8 100644 > --- a/drivers/iio/adc/stm32-adc.c > +++ b/drivers/iio/adc/stm32-adc.c > @@ -217,6 +217,7 @@ struct stm32_adc_cfg { > > /** > * struct stm32_adc - private data of each ADC IIO instance > + * dev: parent device > * @common: reference to ADC block common data > * @offset: ADC instance register offset in ADC block > * @cfg: compatible configuration data > @@ -243,6 +244,7 @@ struct stm32_adc_cfg { > * @int_ch: internal channel indexes array > */ > struct stm32_adc { > + struct device *dev; Can't you use the parent pointer of the indio_dev? > struct stm32_adc_common *common; > u32 offset; > const struct stm32_adc_cfg *cfg; > @@ -1986,8 +1988,7 @@ 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, > - "nvmem access error\n"); > + return dev_err_probe(adc->dev, ret, "nvmem access error\n"); > } > if (ret == -ENOENT) > dev_dbg(&indio_dev->dev, "vrefint calibration not found\n"); > @@ -2221,6 +2222,7 @@ static int stm32_adc_probe(struct platform_device *pdev) > init_completion(&adc->completion); > adc->cfg = (const struct stm32_adc_cfg *) > of_match_device(dev->driver->of_match_table, dev)->data; > + adc->dev = &pdev->dev; There's struct device *dev = &pdev->dev; defined earlier, so you can use dev instead. > > indio_dev->name = dev_name(&pdev->dev); > indio_dev->dev.of_node = pdev->dev.of_node; > Cheers, Ahmad
On Thu, 18 Nov 2021 13:51:44 +0100 Ahmad Fatoum <a.fatoum@pengutronix.de> wrote: > Hello Olivier, > > On 18.11.21 13:39, 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, > > a null pointer error occurs. > > This pointer is set too late on iio_device_register() call, for iio device. > > Even if it were set earlier, you should call dev_err_probe with the dev of > the probe that's currently running. Not any other devices you created since > then. +1 on that > > > So use parent device instead for dev_err_probe() call. > > > > Fixes: 0e346b2cfa85 ("iio: adc: stm32-adc: add vrefint calibration support") > > No line break between these two tags. Greg will reject a pull if there is one (and 0-day probably complain about it...) Jonathan > > Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com> > > --- > > drivers/iio/adc/stm32-adc.c | 6 ++++-- > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c > > index 7f1fb36c747c..14c7c9d390e8 100644 > > --- a/drivers/iio/adc/stm32-adc.c > > +++ b/drivers/iio/adc/stm32-adc.c > > @@ -217,6 +217,7 @@ struct stm32_adc_cfg { > > > > /** > > * struct stm32_adc - private data of each ADC IIO instance > > + * dev: parent device > > * @common: reference to ADC block common data > > * @offset: ADC instance register offset in ADC block > > * @cfg: compatible configuration data > > @@ -243,6 +244,7 @@ struct stm32_adc_cfg { > > * @int_ch: internal channel indexes array > > */ > > struct stm32_adc { > > + struct device *dev; > > Can't you use the parent pointer of the indio_dev? > > > struct stm32_adc_common *common; > > u32 offset; > > const struct stm32_adc_cfg *cfg; > > @@ -1986,8 +1988,7 @@ 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, > > - "nvmem access error\n"); > > + return dev_err_probe(adc->dev, ret, "nvmem access error\n"); > > } > > if (ret == -ENOENT) > > dev_dbg(&indio_dev->dev, "vrefint calibration not found\n"); > > @@ -2221,6 +2222,7 @@ static int stm32_adc_probe(struct platform_device *pdev) > > init_completion(&adc->completion); > > adc->cfg = (const struct stm32_adc_cfg *) > > of_match_device(dev->driver->of_match_table, dev)->data; > > + adc->dev = &pdev->dev; > > There's struct device *dev = &pdev->dev; defined earlier, so you can use dev instead. > > > > > indio_dev->name = dev_name(&pdev->dev); > > indio_dev->dev.of_node = pdev->dev.of_node; > > > > Cheers, > Ahmad >
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 7f1fb36c747c..14c7c9d390e8 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -217,6 +217,7 @@ struct stm32_adc_cfg { /** * struct stm32_adc - private data of each ADC IIO instance + * dev: parent device * @common: reference to ADC block common data * @offset: ADC instance register offset in ADC block * @cfg: compatible configuration data @@ -243,6 +244,7 @@ struct stm32_adc_cfg { * @int_ch: internal channel indexes array */ struct stm32_adc { + struct device *dev; struct stm32_adc_common *common; u32 offset; const struct stm32_adc_cfg *cfg; @@ -1986,8 +1988,7 @@ 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, - "nvmem access error\n"); + return dev_err_probe(adc->dev, ret, "nvmem access error\n"); } if (ret == -ENOENT) dev_dbg(&indio_dev->dev, "vrefint calibration not found\n"); @@ -2221,6 +2222,7 @@ static int stm32_adc_probe(struct platform_device *pdev) init_completion(&adc->completion); adc->cfg = (const struct stm32_adc_cfg *) of_match_device(dev->driver->of_match_table, dev)->data; + adc->dev = &pdev->dev; indio_dev->name = dev_name(&pdev->dev); indio_dev->dev.of_node = pdev->dev.of_node;
dev_err_probe() calls __device_set_deferred_probe_reason() on -EPROBE_DEFER error. If device pointer to driver core private structure is not initialized, a null pointer error occurs. This pointer is set too late on iio_device_register() call, for iio device. So use parent device instead for dev_err_probe() call. Fixes: 0e346b2cfa85 ("iio: adc: stm32-adc: add vrefint calibration support") Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com> --- drivers/iio/adc/stm32-adc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)