Re: [PATCH v2] Add driver to force WMI Thunderbolt controller power status

From: Mika Westerberg
Date: Sat Sep 09 2017 - 03:08:21 EST


On Fri, Sep 08, 2017 at 09:14:52PM -0700, Darren Hart wrote:
> On Fri, Sep 08, 2017 at 03:15:10PM +0000, Mario.Limonciello@xxxxxxxx wrote:
> > > -----Original Message-----
> > > From: Mika Westerberg [mailto:mika.westerberg@xxxxxxxxxxxxxxx]
> > > Sent: Friday, September 8, 2017 3:07 AM
> > > To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>
> > > Cc: dvhart@xxxxxxxxxxxxx; LKML <linux-kernel@xxxxxxxxxxxxxxx>; platform-driver-
> > > x86@xxxxxxxxxxxxxxx; Richard Hughes <hughsient@xxxxxxxxx>; Yehezkel Bernat
> > > <yehezkelshb@xxxxxxxxx>
> > > Subject: Re: [PATCH v2] Add driver to force WMI Thunderbolt controller power
> > > status
> > >
> > > On Thu, Sep 07, 2017 at 01:47:22PM -0500, Mario Limonciello wrote:
> > >
> > > I have a small comment which you might want to consider.
> > >
> > > > +static int intel_wmi_thunderbolt_probe(struct wmi_device *wdev)
> > > > +{
> > > > + return sysfs_create_group(&wdev->dev.kobj, &tbt_attribute_group);
> > > > +}
> > > > +
> > > > +static int intel_wmi_thunderbolt_remove(struct wmi_device *wdev)
> > > > +{
> > > > + sysfs_remove_group(&wdev->dev.kobj, &tbt_attribute_group);
> > > > + return 0;
> > > > +}
> > >
> > > In order to notify userspace about this, what if you send KOBJ_CHANGE
> > > for the wdev when you add/remove this attribute?
> >
> > Sure, makes sense to me. I'll send a follow up patch.
>
> Hrm, what am I missing.... the reason I recommended Mario add the attribute
> group was so this would be automatically taken care of prior to the KOBJ_ADD
> event, per the device documentation:
>
> driver-model/device.txt

At this point the KOBJ_ADD event has already been send to the userspace
when the device was added to the system.