Re: [PATCH v4 4/4] rtc: pcf8525: Add temperature sensor support via hwmon

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] rtc: pcf8525: use devm_release_action() on hwmon error in pcf8525_hwmon_register()
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commit 657bb5e33615f2ed31527354e958f8aeecac64a5
Author: Shiv Prakash Gupta <shivprakash.gupta@nxp.com>

rtc: pcf8525: Add temperature sensor support via hwmon

This commit adds optional hwmon support for the PCF8525 on-chip temperature
sensor, exposing temperature readings and a configurable update interval.

> diff --git a/drivers/rtc/rtc-pcf8525.c b/drivers/rtc/rtc-pcf8525.c
> index f8fbc00bb464d..5cb984958f286 100644
> --- a/drivers/rtc/rtc-pcf8525.c
> +++ b/drivers/rtc/rtc-pcf8525.c
[ ... ]
> @@ -346,6 +349,217 @@ static int pcf8525_rtc_set_offset(struct device *dev, long offset)
[ ... ]
> +static void pcf8525_hwmon_register(struct device *dev,
> +				   struct pcf8525 *pcf8525)
> +{
> +	struct device *hwmon_dev;
> +	int ret;
> +
> +	if (!IS_ENABLED(CONFIG_RTC_DRV_PCF8525_HWMON))
> +		return;
> +
> +	/* Enable the temperature readout before exposing hwmon attributes. */
> +	ret = regmap_update_bits(pcf8525->regmap, PCF8525_REG_CTRL5,
> +				 PCF8525_CTRL5_TEMP_RD_EN,
> +				 PCF8525_CTRL5_TEMP_RD_EN);
> +	if (ret) {
> +		dev_warn(dev, "failed to enable temperature readout: %d\n", ret);
> +		return;
> +	}
> +
> +	/*
> +	 * Register a devm cleanup action to disable the digital
> +	 * temperature readout when the driver is unbound.
> +	 */
> +	if (devm_add_action_or_reset(dev, pcf8525_hwmon_disable_temp, pcf8525)) {
> +		dev_warn(dev, "failed to register HWMON cleanup action\n");
> +		return;
> +	}
> +
> +	/* Only expose sysfs attributes once the hardware is fully ready. */
> +	hwmon_dev = devm_hwmon_device_register_with_info(dev, "pcf8525",
> +							 pcf8525,
> +							 &pcf8525_hwmon_chip_info,
> +							 NULL);
> +	if (IS_ERR(hwmon_dev)) {
> +		dev_warn(dev, "failed to register HWMON device: %ld\n",
> +			 PTR_ERR(hwmon_dev));
> +		pcf8525_hwmon_disable_temp(pcf8525);
> +		return;
> +	}

[Severity: Low]
In pcf8525_hwmon_register() in drivers/rtc/rtc-pcf8525.c, if
devm_hwmon_device_register_with_info() fails after devm_add_action_or_reset()
has already registered pcf8525_hwmon_disable_temp() on dev, calling
pcf8525_hwmon_disable_temp(pcf8525) directly leaves the devres action queued
while pcf8525_probe() succeeds. When the device is later unbound, devres will
invoke pcf8525_hwmon_disable_temp() a second time.

Should this error path call devm_release_action(dev,
pcf8525_hwmon_disable_temp, pcf8525) instead of calling
pcf8525_hwmon_disable_temp(pcf8525) directly?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261030110139.1929109-1-shivprakash.gupta@nxp.com?part=4