Re: [PATCH] platform/x86: wmi: Initialize ACPI device class

[Rafael J. Wysocki]

On Mon, Jan 29, 2024 at 1:51 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> Hi,
>
> On 1/24/24 20:07, Armin Wolf wrote:
> > When an ACPI netlink event is received by acpid, the ACPI device
> > class is passed as its first argument. But since the class string
> > is not initialized, an empty string is being passed:
> >
> >       netlink:  PNP0C14:01 000000d0 00000000
> >
> > Fix this by initializing the ACPI device class during probe.
> >
> > Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
> > ---
> > Note: This patch is based on commit 3f399b5d7189 ("platform/x86: wmi: Use ACPI device name in netlink event")
> > ---
> >  drivers/platform/x86/wmi.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
> > index 7ef1e82dc61c..b92425c30a50 100644
> > --- a/drivers/platform/x86/wmi.c
> > +++ b/drivers/platform/x86/wmi.c
> > @@ -32,6 +32,8 @@
> >  #include <linux/wmi.h>
> >  #include <linux/fs.h>
> >
> > +#define ACPI_WMI_DEVICE_CLASS        "wmi"
> > +
> >  MODULE_AUTHOR("Carlos Corbacho");
> >  MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
> >  MODULE_LICENSE("GPL");
> > @@ -1202,7 +1204,7 @@ static int wmi_notify_device(struct device *dev, void *data)
> >               wblock->handler(*event, wblock->handler_data);
> >       }
> >
> > -     acpi_bus_generate_netlink_event(wblock->acpi_device->pnp.device_class,
> > +     acpi_bus_generate_netlink_event(acpi_device_class(wblock->acpi_device),
> >                                       acpi_dev_name(wblock->acpi_device), *event, 0);
> >
> >       return -EBUSY;
> > @@ -1267,6 +1269,8 @@ static int acpi_wmi_probe(struct platform_device *device)
> >               return -ENODEV;
> >       }
> >
> > +     strscpy(acpi_device_class(acpi_device), ACPI_WMI_DEVICE_CLASS, sizeof(acpi_device_class));
> > +
>
> Hmm, I'm not sure if you are supposed to do this when you are not an
> acpi_driver's add() function.

You aren't.

> Rafael, do you have any comments on this ?

I'm not quite sure why this is done here.