Re: [PATCH v3 2/2] hwmon: acpi_power_meter: convert to hwmon_device_register_with_info

[Guenter Roeck <linux@roeck-us.net>]

Corentin,

On 5/8/22 23:30, Corentin Labbe wrote:
> Booting lead to a hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().
> So let's convert the driver to use hwmon_device_register_with_info().
> 
> Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
> ---
[ ... ]

> @@ -836,20 +740,20 @@ static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
>   		if (res)
>   			break;
>   
> -		remove_attrs(resource);
> +		remove_domain_devices(resource);
>   		setup_attrs(resource);

Zhang Rui found an interesting problem with this code:
It needs a call to sysfs_update_groups(hwmon_dev->groups)
to update sysfs attribute visibility, probably between
remove_domain_devices() and setup_attrs().

>   		break;
>   	case METER_NOTIFY_TRIP:
> -		sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME);
> +		hwmon_notify_event(&device->dev, hwmon_power, hwmon_power_average, 0);

... which makes realize: The notification device should be the hwmon device.
That would be resource->hwmon_dev, not the acpi device.

Thanks,
Guenter