Hi, On 1/30/24 03:10, Armin Wolf wrote: > Am 29.01.24 um 14:08 schrieb 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. > > I believed otherwise, as the ACPI AC driver (which is a platform_driver) does the same thing. > Seems i was wrong on that. I'm pretty sure that the ACPI AC driver used to be an acpi_driver and was converted to a platform_driver recently. AFAIK the plan is to convert all drivers to platform_drivers and completely get rid of the acpi_driver concept. That does mean that we will indeed have platform_drivers now setting the acpi_device_class. So I guess that maybe this is ok to do for the WMI bus driver too, since that is also not a plain driver. >>> Rafael, do you have any comments on this ? >> I'm not quite sure why this is done here. > > The initialization of the ACPI device class is being done to access this value later when sending an > ACPI netlink event like other ACPI drivers do. > > However since you clarified that doing this outside of an acpi_driver's add() function is forbidden > i think it would indeed be better to just pass the value directly without touching the ACPI device class. Right I was thinking that you could just pass the string directly to acpi_bus_generate_netlink_event() myself too. Rafael, do you have any preference for how to solve this ? Regards, Hans