HID: logitech-hidpp: Revert "Don't restart communication if not necessary"

Commit 91cf9a98ae41 ("HID: logitech-hidpp: make .probe usbhid capable")
makes hidpp_probe() first call hid_hw_start(hdev, 0) to allow IO
without connecting any hid subdrivers (hid-input, hidraw).

This is done to allow to retrieve the device's name and serial number
and store these in hdev->name and hdev->uniq.

Then later on IO was stopped and started again with hid_hw_start(hdev,
HID_CONNECT_DEFAULT) connecting hid-input and hidraw after the name
and serial number have been setup.

Commit 498ba2069035 ("HID: logitech-hidpp: Don't restart communication
if not necessary") changed the probe() code to only do the start with
a 0 connect-mask + restart later for unifying devices.

But for non unifying devices hdev->name and hdev->uniq are updated too.
So this change re-introduces the problem for which the start with
a 0 connect-mask + restart later behavior was introduced.

The previous patch in this series changes the unifying path to instead of
restarting IO only call hid_connect() later. This avoids possible issues
with restarting IO seen on non unifying devices.

Revert the change to limit the restart behavior to unifying devices to
fix hdev->name changing after userspace facing devices have already been
registered.

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")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20231010102029.111003-3-hdegoede@redhat.com
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index aa4f232c4518ae969fb3d7eea16fdb6645552e33..c582d19b11d6c21f75842305fde685cfe1b0b289 100644 (file)
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -4394,7 +4394,6 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
        bool connected;
        unsigned int connect_mask = HID_CONNECT_DEFAULT;
        struct hidpp_ff_private_data data;
-       bool will_restart = false;
 
        /* report_fixup needs drvdata to be set before we call hid_parse */
        hidpp = devm_kzalloc(&hdev->dev, sizeof(*hidpp), GFP_KERNEL);
@@ -4445,10 +4444,6 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
                        return ret;
        }
 
-       if (hidpp->quirks & HIDPP_QUIRK_DELAYED_INIT ||
-           hidpp->quirks & HIDPP_QUIRK_UNIFYING)
-               will_restart = true;
-
        INIT_WORK(&hidpp->work, delayed_work_cb);
        mutex_init(&hidpp->send_mutex);
        init_waitqueue_head(&hidpp->wait);
@@ -4465,7 +4460,7 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
         * 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);
+       ret = hid_hw_start(hdev, 0);
        if (ret) {
                hid_err(hdev, "hw start failed\n");
                goto hid_hw_start_fail;
@@ -4504,7 +4499,6 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
                        hidpp->wireless_feature_index = 0;
                else if (ret)
                        goto hid_hw_init_fail;
-               ret = 0;
        }
 
        if (connected && (hidpp->quirks & HIDPP_QUIRK_CLASS_WTP)) {
@@ -4520,16 +4514,14 @@ static int hidpp_probe(struct hid_device *hdev, const struct hid_device_id *id)
        schedule_work(&hidpp->work);
        flush_work(&hidpp->work);
 
-       if (will_restart) {
-               if (hidpp->quirks & HIDPP_QUIRK_DELAYED_INIT)
-                       connect_mask &= ~HID_CONNECT_HIDINPUT;
+       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_connect(hdev, connect_mask);
-               if (ret) {
-                       hid_err(hdev, "%s:hid_connect returned error %d\n", __func__, ret);
-                       goto hid_hw_init_fail;
-               }
+       /* Now export the actual inputs and hidraw nodes to the world */
+       ret = hid_connect(hdev, connect_mask);
+       if (ret) {
+               hid_err(hdev, "%s:hid_connect returned error %d\n", __func__, ret);
+               goto hid_hw_init_fail;
        }
 
        if (hidpp->quirks & HIDPP_QUIRK_CLASS_G920) {