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Bluetooth: Ignore HCI_ERROR_CANCELLED_BY_HOST on adv set terminated event

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This event is received when the controller stops advertising,
specifically for these three reasons:
(a) Connection is successfully created (success).
(b) Timeout is reached (error).
(c) Number of advertising events is reached (error).
(*) This event is NOT generated when the host stops the advertisement.
Refer to the BT spec ver 5.3 vol 4 part E sec 7.7.65.18. Note that the
section was revised from BT spec ver 5.0 vol 2 part E sec 7.7.65.18
which was ambiguous about (*).

Some chips (e.g. RTL8822CE) send this event when the host stops the
advertisement with status = HCI_ERROR_CANCELLED_BY_HOST (due to (*)
above). This is treated as an error and the advertisement will be
removed and userspace will be informed via MGMT event.

On suspend, we are supposed to temporarily disable advertisements,
and continue advertising on resume. However, due to the behavior
above, the advertisements are removed instead.

This patch returns early if HCI_ERROR_CANCELLED_BY_HOST is received.

Btmon snippet of the unexpected behavior:
@ MGMT Command: Remove Advertising (0x003f) plen 1
        Instance: 1
< HCI Command: LE Set Extended Advertising Enable (0x08|0x0039) plen 6
        Extended advertising: Disabled (0x00)
        Number of sets: 1 (0x01)
        Entry 0
          Handle: 0x01
          Duration: 0 ms (0x00)
          Max ext adv events: 0
> HCI Event: LE Meta Event (0x3e) plen 6
      LE Advertising Set Terminated (0x12)
        Status: Operation Cancelled by Host (0x44)
        Handle: 1
        Connection handle: 0
        Number of completed extended advertising events: 5
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Advertising Enable (0x08|0x0039) ncmd 2
        Status: Success (0x00)

Signed-off-by: Archie Pusaka <apusaka@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Archie Pusaka 2021-11-11 13:20:53 +08:00 committed by Marcel Holtmann
parent 9482c5074a
commit 0f281a5e5b
2 changed files with 13 additions and 0 deletions
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1
include/net/bluetooth/hci.h
View File

@ -566,6 +566,7 @@ enum {
#define HCI_ERROR_INVALID_LL_PARAMS 0x1e
#define HCI_ERROR_UNSPECIFIED 0x1f
#define HCI_ERROR_ADVERTISING_TIMEOUT 0x3c
#define HCI_ERROR_CANCELLED_BY_HOST 0x44
/* Flow control modes */
#define HCI_FLOW_CTL_MODE_PACKET_BASED 0x00

12
net/bluetooth/hci_event.c
View File

@ -5533,6 +5533,18 @@ static void hci_le_ext_adv_term_evt(struct hci_dev *hdev, struct sk_buff *skb)
adv = hci_find_adv_instance(hdev, ev->handle);
/* The Bluetooth Core 5.3 specification clearly states that this event
* shall not be sent when the Host disables the advertising set. So in
* case of HCI_ERROR_CANCELLED_BY_HOST, just ignore the event.
*
* When the Host disables an advertising set, all cleanup is done via
* its command callback and not needed to be duplicated here.
*/
if (ev->status == HCI_ERROR_CANCELLED_BY_HOST) {
bt_dev_warn_ratelimited(hdev, "Unexpected advertising set terminated event");
return;
}
if (ev->status) {
if (!adv)
return;