Re: [PATCH v3 1/3] iio: imu: inv_mpu6050: fix unbalanced regulator_disable calls, when probe fails

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Sun, Apr 26, 2026 at 02:23:32PM +0300, Andrey Skvortsov wrote:
> During a probe functions after all regulators are enabled, runtime pm
> is enabled. Before probe function finishes, runtime pm triggers and
> disables vddio regulator. When probe function fails after that,
> inv_mpu_core_disable_regulator_action tries to disable already

Please, use () when we refer to the functions or callbacks:
 — func()
 — .callback()

> disabled by runtime pm vddio regulator causing following backtrace:

PM

>   inv-mpu6050-i2c 1-0068: trigger probe fail -19
>   WARNING: drivers/regulator/core.c:3244 at _regulator_disable+0x2ac/0x600
>   Call trace:
>    _regulator_disable+0x2ac/0x600 (P)
>    regulator_disable+0xac/0x148
>    inv_mpu_core_disable_regulator_vddio_action+0x3c/0xb0 [inv_mpu6050]
>    devm_action_release+0x4c/0x88
>    release_nodes+0xd8/0x178
>    devres_release_group+0x214/0x3c8
>    i2c_device_probe+0x6fc/0x9b0
>   ...
>   inv-mpu6050-i2c 1-0068: Failed to disable vddio regulator: -5
> 
> vddio state is handled in two places: pm_runtime and
> inv_mpu_core_disable_regulator_vddio_action devm action.
> inv_mpu_core_disable_regulator_vddio_action has to check, whether
> regulator is disabled by pm_runtime already. But this information is
> available only after pm_runtime state is initialized by
> pm_runtime_set_active during a probe. So
> inv_mpu_core_disable_regulator_vddio_action has to be called only
> after pm_runtime is properly initialized. To handle cases, when probe
> fails before pm_runtime is enabled, explicitly disable regulators
> in error paths.

As per previous comments.

...

> +	result = devm_add_action_or_reset(dev, inv_mpu_core_disable_regulator_action,
> +					  st);

I would go with a single line despite being long.


> +	if (result)
> +		return dev_err_probe(dev, result,
> +				     "Failed to setup regulator cleanup action\n");

-- 
With Best Regards,
Andy Shevchenko