Re: [PATCHv2 3/7] ACPI: button: Use input_device_enabled() helper

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Friday, May 15, 2020 6:53:27 PM CEST Andrzej Pietrasiewicz wrote:
> A new helper is available, so use it. Inspecting input device's 'users'
> member should be done under device's mutex, so add appropriate invocations.
> 
> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> ---
>  drivers/acpi/button.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
> index 78cfc70cb320..7e081bae48ab 100644
> --- a/drivers/acpi/button.c
> +++ b/drivers/acpi/button.c
> @@ -411,7 +411,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event)
>  		input = button->input;
>  		if (button->type == ACPI_BUTTON_TYPE_LID) {
>  			mutex_lock(&button->input->mutex);
> -			users = button->input->users;
> +			users = input_device_enabled(button->input);
>  			mutex_unlock(&button->input->mutex);
>  			if (users)
>  				acpi_lid_update_state(device, true);
> @@ -456,13 +456,17 @@ static int acpi_button_resume(struct device *dev)
>  {
>  	struct acpi_device *device = to_acpi_device(dev);
>  	struct acpi_button *button = acpi_driver_data(device);
> +	struct input_dev *input = button->input;
>  
>  	button->suspended = false;
> -	if (button->type == ACPI_BUTTON_TYPE_LID && button->input->users) {
> +	mutex_lock(&input->mutex);
> +	if (button->type == ACPI_BUTTON_TYPE_LID &&
> +	    input_device_enabled(input)) {
>  		button->last_state = !!acpi_lid_evaluate_state(device);
>  		button->last_time = ktime_get();
>  		acpi_lid_initialize_state(device);
>  	}
> +	mutex_unlock(&input->mutex);
>  	return 0;
>  }
>  #endif
> 

This appears to conflate a fix (the introduction of the missing mutex locking)
with adding new functionality through input_device_enabled().

Please do the fix separately in advance so it can be backported.

Thanks!