From: Ahmad Fatoum <a.fatoum@pengutronix.de>
To: Olivier Moysan <olivier.moysan@foss.st.com>,
Alexandre Torgue <alexandre.torgue@foss.st.com>,
Fabrice Gasnier <fabrice.gasnier@foss.st.com>,
Jonathan Cameron <jic23@kernel.org>,
Lars-Peter Clausen <lars@metafoo.de>,
Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
Maxime Coquelin <mcoquelin.stm32@gmail.com>,
Wan Jiabing <wanjiabing@vivo.com>, Xu Wang <vulab@iscas.ac.cn>
Cc: linux-arm-kernel@lists.infradead.org, linux-iio@vger.kernel.org,
linux-kernel@vger.kernel.org,
linux-stm32@st-md-mailman.stormreply.com
Subject: Re: [PATCH] iio: adc: stm32: fix null pointer on defer_probe error
Date: Thu, 18 Nov 2021 13:51:44 +0100 [thread overview]
Message-ID: <45a5129a-c0b1-4a07-aef8-d6e0845c7b1a@pengutronix.de> (raw)
In-Reply-To: <20211118123952.15383-1-olivier.moysan@foss.st.com>
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
--
Pengutronix e.K. | |
Steuerwalder Str. 21 | http://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
next prev parent reply other threads:[~2021-11-18 12:56 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-18 12:39 [PATCH] iio: adc: stm32: fix null pointer on defer_probe error Olivier Moysan
2021-11-18 12:51 ` Ahmad Fatoum [this message]
2021-11-18 18:11 ` Jonathan Cameron
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=45a5129a-c0b1-4a07-aef8-d6e0845c7b1a@pengutronix.de \
--to=a.fatoum@pengutronix.de \
--cc=alexandre.torgue@foss.st.com \
--cc=fabrice.gasnier@foss.st.com \
--cc=jic23@kernel.org \
--cc=lars@metafoo.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-iio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-stm32@st-md-mailman.stormreply.com \
--cc=mchehab+huawei@kernel.org \
--cc=mcoquelin.stm32@gmail.com \
--cc=olivier.moysan@foss.st.com \
--cc=vulab@iscas.ac.cn \
--cc=wanjiabing@vivo.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).