Re: [Regression] Logitech BT mouse unusable after commit 532223c8ac57 (still in 6.1-rc8)

[Rafael J. Wysocki]

On Wednesday, December 7, 2022 10:04:43 AM CET Bastien Nocera wrote:
> On Tue, 2022-12-06 at 15:58 +0100, Rafael J. Wysocki wrote:
> > Bastien, Jiri,
> > 
> > Commit 532223c8ac57 ("HID: logitech-hidpp: Enable HID++ for all the
> > Logitech
> > Bluetooth devices") caused my Logitech Bluetooth mouse to become
> > unusable.
> > 
> > Appended is the change I need to make it work again (note that adding
> > the
> > device ID to unhandled_hidpp_devices[] doesn't help, so there must be
> > some
> > significant enough difference in how the two cases are handled in the
> > stack).
> > 
> > Here's what I get in the log without the patch below:
> > 
> > [   36.710574] Bluetooth: HIDP (Human Interface Emulation) ver 1.2
> > [   36.710592] Bluetooth: HIDP socket layer initialized
> > [   36.724644] hid-generic 0005:046D:B016.0001: unknown main item tag
> > 0x0
> > [   36.725860] input: Bluetooth Mouse M336/M337/M535 Mouse as
> > /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-
> > 7:1.0/bluetooth/hci0/hci0:1/0005:046D:B016.0001/input/input14
> > [   36.728036] input: Bluetooth Mouse M336/M337/M535 Consumer Control
> > as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-
> > 7:1.0/bluetooth/hci0/hci0:1/0005:046D:B016.0001/input/input15
> > [   36.728823] input: Bluetooth Mouse M336/M337/M535 Keyboard as
> > /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-
> > 7:1.0/bluetooth/hci0/hci0:1/0005:046D:B016.0001/input/input18
> > [   36.731550] hid-generic 0005:046D:B016.0001: input,hidraw0:
> > BLUETOOTH HID v12.03 Mouse [Bluetooth Mouse M336/M337/M535] on
> > 9c:b6:d0:96:8e:c8
> > [   36.833039] logitech-hidpp-device 0005:046D:B016.0001: unknown
> > main item tag 0x0
> > [   36.999064] logitech-hidpp-device 0005:046D:B016.0001: Device not
> > connected
> > 
> > and here's what I get with it:
> > 
> > [   43.642546] Bluetooth: HIDP (Human Interface Emulation) ver 1.2
> > [   43.642559] Bluetooth: HIDP socket layer initialized
> > [   43.652898] hid-generic 0005:046D:B016.0001: unknown main item tag
> > 0x0
> > [   43.653833] input: Bluetooth Mouse M336/M337/M535 Mouse as
> > /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-
> > 7:1.0/bluetooth/hci0/hci0:1/0005:046D:B016.0001/input/input14
> > [   43.655025] input: Bluetooth Mouse M336/M337/M535 Consumer Control
> > as /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-
> > 7:1.0/bluetooth/hci0/hci0:1/0005:046D:B016.0001/input/input15
> > [   43.655400] input: Bluetooth Mouse M336/M337/M535 Keyboard as
> > /devices/pci0000:00/0000:00:14.0/usb1/1-7/1-
> > 7:1.0/bluetooth/hci0/hci0:1/0005:046D:B016.0001/input/input18
> > [   43.657521] hid-generic 0005:046D:B016.0001: input,hidraw0:
> > BLUETOOTH HID v12.03 Mouse [Bluetooth Mouse M336/M337/M535] on
> > 9c:b6:d0:96:8e:c8
> > 
> > The only difference seems to be that in the former case the logitech-
> > hidpp
> > driver tries to bind to the device, but I guess that is expected. 
> 
> There really shouldn't be that much difference between the 2 paths,
> except that hid-logitech-hidpp.c will check that the device supports
> HID++ in its report descriptors, and then start talking to it to check
> whether it's connected.
> 
> Maybe the device doesn't support HID++?

Quite possibly.

> Can you try running src/tools/hidpp-list-features from
> https://github.com/cvuchener/hidpp on the hidraw device for the mouse?

OK, I'll do that.

> > However,
> > when the device ID is added to unhandled_hidpp_devices[], the
> > messages look
> > exactly like in the "good" case, but the mouse still doesn't work.
> 
> Given that this should be called without ever talking to the device,
> that tells me that there might be a logic bug in the hid-core that uses
> ->probe. Benjamin?

I've explained what happens in this message:

https://lore.kernel.org/lkml/CAJZ5v0jBo-_XnN2m0jeVdeTi7kjr6C3OSzc1NEJgav0srD0JGQ@xxxxxxxxxxxxxx/

and I've just posted patches that fix the issue for me.

Cheers!