in btusb.c [1954:2097]
static int btusb_setup_csr(struct hci_dev *hdev)
{
struct btusb_data *data = hci_get_drvdata(hdev);
u16 bcdDevice = le16_to_cpu(data->udev->descriptor.bcdDevice);
struct hci_rp_read_local_version *rp;
struct sk_buff *skb;
bool is_fake = false;
int ret;
BT_DBG("%s", hdev->name);
skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
HCI_INIT_TIMEOUT);
if (IS_ERR(skb)) {
int err = PTR_ERR(skb);
bt_dev_err(hdev, "CSR: Local version failed (%d)", err);
return err;
}
if (skb->len != sizeof(struct hci_rp_read_local_version)) {
bt_dev_err(hdev, "CSR: Local version length mismatch");
kfree_skb(skb);
return -EIO;
}
rp = (struct hci_rp_read_local_version *)skb->data;
/* Detect a wide host of Chinese controllers that aren't CSR.
*
* Known fake bcdDevices: 0x0100, 0x0134, 0x1915, 0x2520, 0x7558, 0x8891
*
* The main thing they have in common is that these are really popular low-cost
* options that support newer Bluetooth versions but rely on heavy VID/PID
* squatting of this poor old Bluetooth 1.1 device. Even sold as such.
*
* We detect actual CSR devices by checking that the HCI manufacturer code
* is Cambridge Silicon Radio (10) and ensuring that LMP sub-version and
* HCI rev values always match. As they both store the firmware number.
*/
if (le16_to_cpu(rp->manufacturer) != 10 ||
le16_to_cpu(rp->hci_rev) != le16_to_cpu(rp->lmp_subver))
is_fake = true;
/* Known legit CSR firmware build numbers and their supported BT versions:
* - 1.1 (0x1) -> 0x0073, 0x020d, 0x033c, 0x034e
* - 1.2 (0x2) -> 0x04d9, 0x0529
* - 2.0 (0x3) -> 0x07a6, 0x07ad, 0x0c5c
* - 2.1 (0x4) -> 0x149c, 0x1735, 0x1899 (0x1899 is a BlueCore4-External)
* - 4.0 (0x6) -> 0x1d86, 0x2031, 0x22bb
*
* e.g. Real CSR dongles with LMP subversion 0x73 are old enough that
* support BT 1.1 only; so it's a dead giveaway when some
* third-party BT 4.0 dongle reuses it.
*/
else if (le16_to_cpu(rp->lmp_subver) <= 0x034e &&
le16_to_cpu(rp->hci_ver) > BLUETOOTH_VER_1_1)
is_fake = true;
else if (le16_to_cpu(rp->lmp_subver) <= 0x0529 &&
le16_to_cpu(rp->hci_ver) > BLUETOOTH_VER_1_2)
is_fake = true;
else if (le16_to_cpu(rp->lmp_subver) <= 0x0c5c &&
le16_to_cpu(rp->hci_ver) > BLUETOOTH_VER_2_0)
is_fake = true;
else if (le16_to_cpu(rp->lmp_subver) <= 0x1899 &&
le16_to_cpu(rp->hci_ver) > BLUETOOTH_VER_2_1)
is_fake = true;
else if (le16_to_cpu(rp->lmp_subver) <= 0x22bb &&
le16_to_cpu(rp->hci_ver) > BLUETOOTH_VER_4_0)
is_fake = true;
/* Other clones which beat all the above checks */
else if (bcdDevice == 0x0134 &&
le16_to_cpu(rp->lmp_subver) == 0x0c5c &&
le16_to_cpu(rp->hci_ver) == BLUETOOTH_VER_2_0)
is_fake = true;
if (is_fake) {
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.
* Probably will need to be expanded in the future;
* without these the controller will lock up.
*/
set_bit(HCI_QUIRK_BROKEN_STORED_LINK_KEY, &hdev->quirks);
set_bit(HCI_QUIRK_BROKEN_ERR_DATA_REPORTING, &hdev->quirks);
/* Clear the reset quirk since this is not an actual
* early Bluetooth 1.1 device from CSR.
*/
clear_bit(HCI_QUIRK_RESET_ON_CLOSE, &hdev->quirks);
clear_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
/*
* 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
* (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.
*
* 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.
*/
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");
pm_runtime_forbid(&data->udev->dev);
device_set_wakeup_capable(&data->udev->dev, false);
/* Re-enable autosuspend if this was requested */
if (enable_autosuspend)
usb_enable_autosuspend(data->udev);
}
kfree_skb(skb);
return 0;
}