HID: logitech-hidpp: Don't restart IO, instead defer hid_connect() only

Restarting IO causes 2 problems:

1. Some devices do not like IO being restarted this was addressed in
   commit 498ba20690 ("HID: logitech-hidpp: Don't restart communication
   if not necessary"), but that change has issues of its own and needs to
   be reverted.

2. Restarting IO and specifically calling hid_device_io_stop() causes
   received packets to be missed, which may cause connect-events to
   get missed.

Restarting IO was introduced in commit 91cf9a98ae ("HID: logitech-hidpp:
make .probe usbhid capable") to allow to retrieve the device's name and
serial number and store these in hdev->name and hdev->uniq before
connecting any hid subdrivers (hid-input, hidraw) exporting this info
to userspace.

But this does not require restarting IO, this merely requires deferring
calling hid_connect(). Calling hid_hw_start() with a connect-mask of
0 makes it skip calling hid_connect(), so hidpp_probe() can simply call
hid_connect() later without needing to restart IO.

Remove the stop + restart of IO and instead just call hid_connect() later
to avoid the issues caused by restarting IO.

Now that IO is no longer stopped, hid_hw_close() must be called at the end
of probe() to balance the hid_hw_open() done at the beginning probe().

This series has been tested on the following devices:
Logitech Bluetooth Laser Travel Mouse (bluetooth, HID++ 1.0)
Logitech M720 Triathlon (bluetooth, HID++ 4.5)
Logitech M720 Triathlon (unifying, HID++ 4.5)
Logitech K400 Pro (unifying, HID++ 4.1)
Logitech K270 (eQUAD nano Lite, HID++ 2.0)
Logitech M185 (eQUAD nano Lite, HID++ 4.5)
Logitech LX501 keyboard (27 Mhz, HID++ builtin scroll-wheel, HID++ 1.0)
Logitech M-RAZ105 mouse (27 Mhz, HID++ extra mouse buttons, HID++ 1.0)

And by bentiss:
Logitech Touchpad T650 (unifying)
Logitech Touchpad T651 (bluetooth)
Logitech MX Master 3B (BLE)
Logitech G403 (plain USB / Gaming receiver)

Fixes: 498ba20690 ("HID: logitech-hidpp: Don't restart communication if not necessary")
Suggested-by: Benjamin Tissoires <bentiss@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20231010102029.111003-2-hdegoede@redhat.com
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
This commit is contained in:
Hans de Goede 2023-10-10 12:20:18 +02:00 committed by Benjamin Tissoires
parent bab19d1b21
commit 11ca0322a4

View File

@ -4460,8 +4460,10 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
hdev->name);
/*
* Plain USB connections need to actually call start and open
* on the transport driver to allow incoming data.
* First call hid_hw_start(hdev, 0) to allow IO without connecting any
* hid subdrivers (hid-input, hidraw). This allows retrieving the dev's
* name and serial number and store these in hdev->name and hdev->uniq,
* before the hid-input and hidraw drivers expose these to userspace.
*/
ret = hid_hw_start(hdev, will_restart ? 0 : connect_mask);
if (ret) {
@ -4519,19 +4521,14 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
flush_work(&hidpp->work);
if (will_restart) {
/* Reset the HID node state */
hid_device_io_stop(hdev);
hid_hw_close(hdev);
hid_hw_stop(hdev);
if (hidpp->quirks & HIDPP_QUIRK_DELAYED_INIT)
connect_mask &= ~HID_CONNECT_HIDINPUT;
/* Now export the actual inputs and hidraw nodes to the world */
ret = hid_hw_start(hdev, connect_mask);
ret = hid_connect(hdev, connect_mask);
if (ret) {
hid_err(hdev, "%s:hid_hw_start returned error\n", __func__);
goto hid_hw_start_fail;
hid_err(hdev, "%s:hid_connect returned error %d\n", __func__, ret);
goto hid_hw_init_fail;
}
}
@ -4543,6 +4540,11 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
ret);
}
/*
* This relies on logi_dj_ll_close() being a no-op so that DJ connection
* events will still be received.
*/
hid_hw_close(hdev);
return ret;
hid_hw_init_fail: