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.
Cc: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Changes in v2:
- This is a new patch in v2 of this patch-set
---
include/net/bluetooth/hci.h | 8 ++++++++
net/bluetooth/hci_core.c | 18 +++++++++++-------
2 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index c1504aa3d9cf..ba2f439bc04d 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 9d2c9a1c552f..9d8dbb38585c 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3827,10 +3827,12 @@ 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);
@@ -3865,9 +3867,11 @@ 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);
--
2.29.2
