On Fri, Nov 03, 2017 at 11:27:22AM -0500, Mario Limonciello wrote: > dell-wmi and dell-smbios-wmi are dependent upon dell-wmi-descriptor > finishing probe successfully to probe themselves. > > Currently if dell-wmi-descriptor fails probing in a non-recoverable way > (such as invalid header) dell-wmi and dell-smbios-wmi will continue to > try to redo probing due to deferred probing. > > To solve this have the dependent drivers query the dell-wmi-descriptor > driver whether the descriptor has been determined valid. The possible > results are: > -EPROBE_DEFER: Descriptor not yet probed, dependent driver should wait > and use deferred probing > < 0: Descriptor probed, invalid. Dependent driver should return an > error. > 0: Successful descriptor probe, dependent driver can continue > > Successful descriptor probe still doesn't mean that the descriptor driver > is necessarily bound at the time of initialization of dependent driver. > Userspace can unbind the driver, so all methods used from driver Userspace shouldn't be able to remove the dell-wmi-descriptor driver if a dependent driver is loaded. It isn't clear to me in which scenario we encounter this problem ?? > should still be verified to return success values otherwise deferred > probing be used. The part after "otherwise" is breaking my English parser... Should this read: "Userspace can unbind the driver, so all methods used from the driver should still be verified to return successful values, falling back to deferred probing in case of failure." ?? > diff --git a/drivers/platform/x86/dell-wmi-descriptor.h b/drivers/platform/x86/dell-wmi-descriptor.h > index 5f7b69c2c83a..776cddd5e135 100644 > --- a/drivers/platform/x86/dell-wmi-descriptor.h > +++ b/drivers/platform/x86/dell-wmi-descriptor.h > @@ -15,6 +15,13 @@ > > #define DELL_WMI_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" > > +/* possible return values: This should trigger a checkpatch error, but doesn't. Huh. For everything but "net", comment blocks should start with /* and not following text. /* * First line. * Second line. */ A nit, and I can clean up if no changes are deemed necessary here. > + * -EPROBE_DEFER: probing for dell-wmi-descriptor not yet run > + * 0: valid descriptor, successfully probed > + * < 0: invalid descriptor, don't probe dependent devices > + */ -- Darren Hart VMware Open Source Technology Center
