Re: [PATCH V3] soc: imx8m: Unregister cpufreq and soc dev in cleanup path

From: Marco Felsch
Date: Fri Feb 14 2025 - 01:30:21 EST


Hi Peng,

On 25-02-14, Peng Fan wrote:
> Hi Shawn,
>
> On Thu, Dec 19, 2024 at 10:50:29PM +0800, Peng Fan (OSS) wrote:
> >From: Peng Fan <peng.fan@xxxxxxx>
> >
> >Unregister the cpufreq device and soc device when resource unwinding,
> >otherwise there will be warning when do removing test:
> >sysfs: cannot create duplicate filename '/devices/platform/imx-cpufreq-dt'
> >CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.13.0-rc1-next-20241204
> >Hardware name: NXP i.MX8MPlus EVK board (DT)
> >
> >Fixes: 9cc832d37799 ("soc: imx8m: Probe the SoC driver as platform driver")
> >Cc: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> >Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> >---
>
> Any comments?
>
> Thanks,
> Peng
>
> >
> >V3:
> > Per Marco, drop remove function, use devm_add_action and update the patch
> > title accordingly.
> >
> >V2:
> > Add err check when create the cpufreq platform device
> > https://lore.kernel.org/all/20241217015826.1374497-1-peng.fan@xxxxxxxxxxx/

This is got lost. Albeit platform_device_unregister() can handle
IS_ERROR() cases I don't like the fact that we do not return the error
if there is any during probe. Please see below.

> >
> > drivers/soc/imx/soc-imx8m.c | 23 +++++++++++++++++++++--
> > 1 file changed, 21 insertions(+), 2 deletions(-)
> >
> >diff --git a/drivers/soc/imx/soc-imx8m.c b/drivers/soc/imx/soc-imx8m.c
> >index 8ac7658e3d52..585631b7ae44 100644
> >--- a/drivers/soc/imx/soc-imx8m.c
> >+++ b/drivers/soc/imx/soc-imx8m.c
> >@@ -192,9 +192,20 @@ static __maybe_unused const struct of_device_id imx8_soc_match[] = {
> > devm_kasprintf((dev), GFP_KERNEL, "%d.%d", ((soc_rev) >> 4) & 0xf, (soc_rev) & 0xf) : \
> > "unknown"
> >
> >+static void imx8m_unregister_soc(void *data)
> >+{
> >+ soc_device_unregister(data);
> >+}
> >+
> >+static void imx8m_unregister_cpufreq(void *data)
> >+{
> >+ platform_device_unregister(data);
> >+}
> >+
> > static int imx8m_soc_probe(struct platform_device *pdev)
> > {
> > struct soc_device_attribute *soc_dev_attr;
> >+ struct platform_device *cpufreq_dev;
> > const struct imx8_soc_data *data;
> > struct device *dev = &pdev->dev;
> > const struct of_device_id *id;
> >@@ -239,11 +250,19 @@ static int imx8m_soc_probe(struct platform_device *pdev)
> > if (IS_ERR(soc_dev))
> > return PTR_ERR(soc_dev);
> >
> >+ ret = devm_add_action(dev, imx8m_unregister_soc, soc_dev);
> >+ if (ret)
> >+ return ret;
> >+
> > pr_info("SoC: %s revision %s\n", soc_dev_attr->soc_id,
> > soc_dev_attr->revision);
> >
> >- if (IS_ENABLED(CONFIG_ARM_IMX_CPUFREQ_DT))
> >- platform_device_register_simple("imx-cpufreq-dt", -1, NULL, 0);
> >+ if (IS_ENABLED(CONFIG_ARM_IMX_CPUFREQ_DT)) {
> >+ cpufreq_dev = platform_device_register_simple("imx-cpufreq-dt", -1, NULL, 0);
if (IS_ERROR(cpufreq_dev))
return dev_err_probe(dev, "Failed to imx-cpufreq-dev device\n",
PTR_ERR(cpufreq_dev));

Regards,
Marco

> >+ ret = devm_add_action(dev, imx8m_unregister_cpufreq, cpufreq_dev);
> >+ if (ret)
> >+ return ret;
> >+ }
> >
> > return 0;
> > }
> >--
> >2.37.1
> >
> >
>