From 635caea216dce2cc5b166e1782637881178495c3 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 10 Oct 2023 12:20:18 +0200 Subject: [PATCH] HID: logitech-hidpp: Don't restart IO, instead defer hid_connect() only [ Upstream commit 11ca0322a41920df2b462d2e45b0731e47ff475b ] Restarting IO causes 2 problems: 1. Some devices do not like IO being restarted this was addressed in commit 498ba2069035 ("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 91cf9a98ae41 ("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: 498ba2069035 ("HID: logitech-hidpp: Don't restart communication if not necessary") Suggested-by: Benjamin Tissoires Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20231010102029.111003-2-hdegoede@redhat.com Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin --- drivers/hid/hid-logitech-hidpp.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index a209d51..aa4f232 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -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: -- 2.7.4