[PATCH v2] platform/x86: adv_swbutton: use devm_add_action_or_reset() for cleanup

[PATCH v2] platform/x86: adv_swbutton: use devm_add_action_or_reset() for cleanup

[Joe Hattori]

Current code leaves the device's wakeup enabled in the error path of
.probe() and .remove(). Also, the registered input device is not
unregistered. Add a devm_add_action_or_reset() call and cleanup these
resources in the callback.

Fixes: 3d904005f686 ("platform/x86: add support for Advantech software defined button")
Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
---
Changes in V2:
- Use devm_add_action_or_reset().
- Call input_unregister_device().
---
 drivers/platform/x86/adv_swbutton.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/platform/x86/adv_swbutton.c b/drivers/platform/x86/adv_swbutton.c
index 6fa60f3fc53c..5b07c42adfad 100644
--- a/drivers/platform/x86/adv_swbutton.c
+++ b/drivers/platform/x86/adv_swbutton.c
@@ -44,6 +44,14 @@ static void adv_swbutton_notify(acpi_handle handle, u32 event, void *context)
 	}
 }
 
+static void adv_swbutton_release(void *__input)
+{
+	struct input_dev *input = __input;
+
+	input_unregister_device(input);
+	device_init_wakeup(input->dev.parent, false);
+}
+
 static int adv_swbutton_probe(struct platform_device *device)
 {
 	struct adv_swbutton *button;
@@ -78,6 +86,9 @@ static int adv_swbutton_probe(struct platform_device *device)
 
 	device_init_wakeup(&device->dev, true);
 
+	if (devm_add_action_or_reset(&device->dev, adv_swbutton_release, input))
+		return -ENOMEM;
+
 	status = acpi_install_notify_handler(handle,
 					     ACPI_DEVICE_NOTIFY,
 					     adv_swbutton_notify,
-- 
2.34.1

Re: [PATCH v2] platform/x86: adv_swbutton: use devm_add_action_or_reset() for cleanup

[Ilpo Järvinen]

On Wed, 11 Dec 2024, Joe Hattori wrote:

> Current code leaves the device's wakeup enabled in the error path of
> .probe() and .remove(). Also, the registered input device is not
> unregistered. Add a devm_add_action_or_reset() call and cleanup these
> resources in the callback.
> 
> Fixes: 3d904005f686 ("platform/x86: add support for Advantech software defined button")
> Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
> ---
> Changes in V2:
> - Use devm_add_action_or_reset().
> - Call input_unregister_device().
> ---
>  drivers/platform/x86/adv_swbutton.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/platform/x86/adv_swbutton.c b/drivers/platform/x86/adv_swbutton.c
> index 6fa60f3fc53c..5b07c42adfad 100644
> --- a/drivers/platform/x86/adv_swbutton.c
> +++ b/drivers/platform/x86/adv_swbutton.c
> @@ -44,6 +44,14 @@ static void adv_swbutton_notify(acpi_handle handle, u32 event, void *context)
>  	}
>  }
>  
> +static void adv_swbutton_release(void *__input)
> +{
> +	struct input_dev *input = __input;
> +
> +	input_unregister_device(input);

Better but the input device is managed so the unregister call is 
unnecessary.

devm_input_allocate_device() comment says:

 * Managed input devices do not need to be explicitly unregistered or
 * freed as it will be done automatically when owner device unbinds from
 * its driver (or binding fails). Once managed input device is allocated,
 * it is ready to be set up and registered in the same fashion as regular
 * input device. There are no special devm_input_device_[un]register()
 * variants, regular ones work with both managed and unmanaged devices,
 * should you need them. In most cases however, managed input device need
 * not be explicitly unregistered or freed.

-- 
 i.

> +	device_init_wakeup(input->dev.parent, false);
> +}
> +
>  static int adv_swbutton_probe(struct platform_device *device)
>  {
>  	struct adv_swbutton *button;
> @@ -78,6 +86,9 @@ static int adv_swbutton_probe(struct platform_device *device)
>  
>  	device_init_wakeup(&device->dev, true);
>  
> +	if (devm_add_action_or_reset(&device->dev, adv_swbutton_release, input))
> +		return -ENOMEM;
> +
>  	status = acpi_install_notify_handler(handle,
>  					     ACPI_DEVICE_NOTIFY,
>  					     adv_swbutton_notify,
> 

Re: [PATCH v2] platform/x86: adv_swbutton: use devm_add_action_or_reset() for cleanup

[Joe Hattori]

Hi Ilpo,

Thank you for your review.
I am currently submitting a patch to introduce the devm_ version of 
device_init_wakeup(dev, true) [1], and I would like to send a V3 patch 
utilizing it after it is merged.

[1]: 
https://lore.kernel.org/linux-pm/20241214021652.3432500-1-joe@pf.is.s.u-tokyo.ac.jp/T/#u

On 12/11/24 22:57, Ilpo Järvinen wrote:
> On Wed, 11 Dec 2024, Joe Hattori wrote:
> 
>> Current code leaves the device's wakeup enabled in the error path of
>> .probe() and .remove(). Also, the registered input device is not
>> unregistered. Add a devm_add_action_or_reset() call and cleanup these
>> resources in the callback.
>>
>> Fixes: 3d904005f686 ("platform/x86: add support for Advantech software defined button")
>> Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
>> ---
>> Changes in V2:
>> - Use devm_add_action_or_reset().
>> - Call input_unregister_device().
>> ---
>>   drivers/platform/x86/adv_swbutton.c | 11 +++++++++++
>>   1 file changed, 11 insertions(+)
>>
>> diff --git a/drivers/platform/x86/adv_swbutton.c b/drivers/platform/x86/adv_swbutton.c
>> index 6fa60f3fc53c..5b07c42adfad 100644
>> --- a/drivers/platform/x86/adv_swbutton.c
>> +++ b/drivers/platform/x86/adv_swbutton.c
>> @@ -44,6 +44,14 @@ static void adv_swbutton_notify(acpi_handle handle, u32 event, void *context)
>>   	}
>>   }
>>   
>> +static void adv_swbutton_release(void *__input)
>> +{
>> +	struct input_dev *input = __input;
>> +
>> +	input_unregister_device(input);
> 
> Better but the input device is managed so the unregister call is
> unnecessary.
> 
> devm_input_allocate_device() comment says:
> 
>   * Managed input devices do not need to be explicitly unregistered or
>   * freed as it will be done automatically when owner device unbinds from
>   * its driver (or binding fails). Once managed input device is allocated,
>   * it is ready to be set up and registered in the same fashion as regular
>   * input device. There are no special devm_input_device_[un]register()
>   * variants, regular ones work with both managed and unmanaged devices,
>   * should you need them. In most cases however, managed input device need
>   * not be explicitly unregistered or freed.

Thank you for pointing out, will be fixed in the V3 patch.
> 

Best,
Joe