Re: HID: logitech-hidpp: G920 FF init fails with -110 since "move FF initialization to .input_configured()"

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Gideon,

On Mon, Nov 02, 2026 at 02:23:18PM +0100, Gideon Heinz wrote:
> This looks like a regression from commit
> 544315e401727364f7ce3ba771a36f7dc24ba6c4 ("HID:
> logitech-hidpp: move FF initialization to .input_configured()",
> 2026-08-14). It moves g920_get_config()/hidpp_ff_init() from
> hidpp_probe(), where they ran after schedule_work()/flush_work() of the
> connect event, into hidpp_input_configured(), which is called from
> hid_hw_start() before that work runs. That matches the capture: the
> wheel answers the 0x8123 lookup normally, the driver doesn't act on the
> reply and gives up after 3 tries with -ETIMEDOUT. I haven't tested a
> revert. Happy to test patches.

Thank you for the report and the usbmon captures.

The issue is that hidpp_probe() calls hid_device_io_stop() right before
hid_connect(), so incoming HID reports are dropped with -EBUSY while
hidpp_input_configured() runs g920_get_config(). Re-enabling I/O around
g920_get_config() (matching what hid-pidff and hid-haptic do during
hid_connect()) should fix it.

Could you please give the patch below a try and let me know if it
resolves the issue?

Thanks.

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index 9646380febac..6b1f55483385 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -4098,7 +4098,9 @@ static int hidpp_input_configured(struct hid_device *hdev, struct hid_input *hid
 		if (!list_is_first(&hidinput->list, &hdev->inputs))
 			return 0;
 
+		hid_device_io_start(hdev);
 		ret = g920_get_config(hidpp, &data);
+		hid_device_io_stop(hdev);
 		if (!ret)
 			ret = hidpp_ff_init(hidpp, &data);
 

-- 
Dmitry