This is a note to let you know that I've just added the patch titled Bluetooth: Add new HCI_QUIRK_NO_SUSPEND_NOTIFIER quirk to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bluetooth-add-new-hci_quirk_no_suspend_notifier-quir.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3f2f713cd144c0e1b4fc441bca7a5264bb4fcd58 Author: Hans de Goede <hdegoede@xxxxxxxxxx> Date: Thu Jan 28 17:33:12 2021 +0100 Bluetooth: Add new HCI_QUIRK_NO_SUSPEND_NOTIFIER quirk [ Upstream commit 219991e6be7f4a31d471611e265b72f75b2d0538 ] Some devices, e.g. the RTL8723BS bluetooth part, some USB attached devices, completely drop from the bus on a system-suspend. These devices will have their driver unbound and rebound on resume (when the dropping of the bus gets detected) and will show up as a new HCI after resume. These devices do not benefit from the suspend / resume handling work done by the hci_suspend_notifier. At best this unnecessarily adds some time to the suspend/resume time. But this may also actually cause problems, if the code doing the driver unbinding runs after the pm-notifier then the hci_suspend_notifier code will try to talk to a device which is now in an uninitialized state. This commit adds a new HCI_QUIRK_NO_SUSPEND_NOTIFIER quirk which allows drivers to opt-out of the hci_suspend_notifier when they know beforehand that their device will be fully re-initialized / reprobed on resume. Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index c8e67042a3b1..6da4b3c5dd55 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -238,6 +238,14 @@ enum { * during the hdev->setup vendor callback. */ HCI_QUIRK_BROKEN_ERR_DATA_REPORTING, + + /* + * When this quirk is set, then the hci_suspend_notifier is not + * registered. This is intended for devices which drop completely + * from the bus on system-suspend and which will show up as a new + * HCI after resume. + */ + HCI_QUIRK_NO_SUSPEND_NOTIFIER, }; /* HCI device flags */ diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 7a2f9559e99a..0152bc6b6796 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -3785,10 +3785,12 @@ int hci_register_dev(struct hci_dev *hdev) hci_sock_dev_event(hdev, HCI_DEV_REG); hci_dev_hold(hdev); - hdev->suspend_notifier.notifier_call = hci_suspend_notifier; - error = register_pm_notifier(&hdev->suspend_notifier); - if (error) - goto err_wqueue; + if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks)) { + hdev->suspend_notifier.notifier_call = hci_suspend_notifier; + error = register_pm_notifier(&hdev->suspend_notifier); + if (error) + goto err_wqueue; + } queue_work(hdev->req_workqueue, &hdev->power_on); @@ -3823,9 +3825,11 @@ void hci_unregister_dev(struct hci_dev *hdev) cancel_work_sync(&hdev->power_on); - hci_suspend_clear_tasks(hdev); - unregister_pm_notifier(&hdev->suspend_notifier); - cancel_work_sync(&hdev->suspend_prepare); + if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks)) { + hci_suspend_clear_tasks(hdev); + unregister_pm_notifier(&hdev->suspend_notifier); + cancel_work_sync(&hdev->suspend_prepare); + } hci_dev_do_close(hdev);