Bluetooth: btusb: Make the CSR clone chip force-suspend workaround more generic

Turns out Hans de Goede completed the work I started last year trying to
improve Chinese-clone detection of CSR controller chips. Quirk after quirk
these Bluetooth dongles are more usable now.

Even after a few BlueZ regressions; these clones are so fickle that some
days they stop working altogether. Except on Windows, they work fine.

But this force-suspend initialization quirk seems to mostly do the trick,
after a lot of testing Bluetooth now seems to work *all* the time.

The only problem is that the solution ended up being masked under a very
stringent check; when there are probably hundreds of fake dongle
models out there that benefit from a good reset. Make it so.

Fixes: 81cac64ba258a ("Bluetooth: Deal with USB devices that are faking CSR vendor")
Fixes: cde1a8a992875 ("Bluetooth: btusb: Fix and detect most of the Chinese Bluetooth controllers")
Fixes: d74e0ae7e0303 ("Bluetooth: btusb: Fix detection of some fake CSR controllers with a bcdDevice val of 0x0134")
Fixes: 0671c0662383e ("Bluetooth: btusb: Add workaround for remote-wakeup issues with Barrot 8041a02 fake CSR controllers")

Cc: stable@vger.kernel.org
Cc: Hans de Goede <hdegoede@redhat.com>
Tested-by: Ismael Ferreras Morezuelas <swyterzone@gmail.com>
Signed-off-by: Ismael Ferreras Morezuelas <swyterzone@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 07cb5d9..fec798d 100644 (file)
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -1900,7 +1900,7 @@ static int btusb_setup_csr(struct hci_dev *hdev)
                is_fake = true;
 
        if (is_fake) {
-               bt_dev_warn(hdev, "CSR: Unbranded CSR clone detected; adding workarounds...");
+               bt_dev_warn(hdev, "CSR: Unbranded CSR clone detected; adding workarounds and force-suspending once...");
 
                /* Generally these clones have big discrepancies between
                 * advertised features and what's actually supported.
@@ -1917,41 +1917,46 @@ static int btusb_setup_csr(struct hci_dev *hdev)
                clear_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
 
                /*
-                * Special workaround for clones with a Barrot 8041a02 chip,
-                * these clones are really messed-up:
-                * 1. Their bulk rx endpoint will never report any data unless
-                * the device was suspended at least once (yes really).
+                * Special workaround for these BT 4.0 chip clones, and potentially more:
+                *
+                * - 0x0134: a Barrot 8041a02                 (HCI rev: 0x1012 sub: 0x0810)
+                * - 0x7558: IC markings FR3191AHAL 749H15143 (HCI rev/sub-version: 0x0709)
+                *
+                * These controllers are really messed-up.
+                *
+                * 1. Their bulk RX endpoint will never report any data unless
+                * the device was suspended at least once (yes, really).
                 * 2. They will not wakeup when autosuspended and receiving data
-                * on their bulk rx endpoint from e.g. a keyboard or mouse
+                * on their bulk RX endpoint from e.g. a keyboard or mouse
                 * (IOW remote-wakeup support is broken for the bulk endpoint).
                 *
                 * To fix 1. enable runtime-suspend, force-suspend the
-                * hci and then wake-it up by disabling runtime-suspend.
+                * HCI and then wake-it up by disabling runtime-suspend.
                 *
-                * To fix 2. clear the hci's can_wake flag, this way the hci
+                * To fix 2. clear the HCI's can_wake flag, this way the HCI
                 * will still be autosuspended when it is not open.
+                *
+                * --
+                *
+                * Because these are widespread problems we prefer generic solutions; so
+                * apply this initialization quirk to every controller that gets here,
+                * it should be harmless. The alternative is to not work at all.
                 */
-               if (bcdDevice == 0x8891 &&
-                   le16_to_cpu(rp->lmp_subver) == 0x1012 &&
-                   le16_to_cpu(rp->hci_rev) == 0x0810 &&
-                   le16_to_cpu(rp->hci_ver) == BLUETOOTH_VER_4_0) {
-                       bt_dev_warn(hdev, "CSR: detected a fake CSR dongle using a Barrot 8041a02 chip, this chip is very buggy and may have issues");
+               pm_runtime_allow(&data->udev->dev);
 
-                       pm_runtime_allow(&data->udev->dev);
+               ret = pm_runtime_suspend(&data->udev->dev);
+               if (ret >= 0)
+                       msleep(200);
+               else
+                       bt_dev_err(hdev, "CSR: Failed to suspend the device for our Barrot 8041a02 receive-issue workaround");
 
-                       ret = pm_runtime_suspend(&data->udev->dev);
-                       if (ret >= 0)
-                               msleep(200);
-                       else
-                               bt_dev_err(hdev, "Failed to suspend the device for Barrot 8041a02 receive-issue workaround");
+               pm_runtime_forbid(&data->udev->dev);
 
-                       pm_runtime_forbid(&data->udev->dev);
+               device_set_wakeup_capable(&data->udev->dev, false);
 
-                       device_set_wakeup_capable(&data->udev->dev, false);
-                       /* Re-enable autosuspend if this was requested */
-                       if (enable_autosuspend)
-                               usb_enable_autosuspend(data->udev);
-               }
+               /* Re-enable autosuspend if this was requested */
+               if (enable_autosuspend)
+                       usb_enable_autosuspend(data->udev);
        }
 
        kfree_skb(skb);