From 4f40afc6c76451daff7d0dcfc8a3d113ccf65bfc Mon Sep 17 00:00:00 2001 From: Abhishek Pandit-Subedi Date: Wed, 11 Mar 2020 08:54:01 -0700 Subject: Bluetooth: Handle BR/EDR devices during suspend To handle BR/EDR devices, we first disable page scan and disconnect all connected devices. Once that is complete, we add event filters (for devices that can wake the system) and re-enable page scan. Signed-off-by: Abhishek Pandit-Subedi Signed-off-by: Marcel Holtmann --- net/bluetooth/hci_core.c | 22 +++++++-- net/bluetooth/hci_event.c | 24 ++++++++++ net/bluetooth/hci_request.c | 106 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 149 insertions(+), 3 deletions(-) (limited to 'net/bluetooth') diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 39aa21a1fe92..dbd2ad3a26ed 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -3325,16 +3325,31 @@ static int hci_suspend_notifier(struct notifier_block *nb, unsigned long action, goto done; if (action == PM_SUSPEND_PREPARE) { - hdev->suspend_state_next = BT_SUSPENDED; + /* Suspend consists of two actions: + * - First, disconnect everything and make the controller not + * connectable (disabling scanning) + * - Second, program event filter/whitelist and enable scan + */ + hdev->suspend_state_next = BT_SUSPEND_DISCONNECT; set_bit(SUSPEND_PREPARE_NOTIFIER, hdev->suspend_tasks); queue_work(hdev->req_workqueue, &hdev->suspend_prepare); - ret = hci_suspend_wait_event(hdev); + + /* If the disconnect portion failed, don't attempt to complete + * by configuring the whitelist. The suspend notifier will + * follow a cancelled suspend with a PM_POST_SUSPEND + * notification. + */ + if (!ret) { + hdev->suspend_state_next = BT_SUSPEND_COMPLETE; + set_bit(SUSPEND_PREPARE_NOTIFIER, hdev->suspend_tasks); + queue_work(hdev->req_workqueue, &hdev->suspend_prepare); + ret = hci_suspend_wait_event(hdev); + } } else if (action == PM_POST_SUSPEND) { hdev->suspend_state_next = BT_RUNNING; set_bit(SUSPEND_PREPARE_NOTIFIER, hdev->suspend_tasks); queue_work(hdev->req_workqueue, &hdev->suspend_prepare); - ret = hci_suspend_wait_event(hdev); } @@ -3399,6 +3414,7 @@ struct hci_dev *hci_alloc_dev(void) INIT_LIST_HEAD(&hdev->mgmt_pending); INIT_LIST_HEAD(&hdev->blacklist); INIT_LIST_HEAD(&hdev->whitelist); + INIT_LIST_HEAD(&hdev->wakeable); INIT_LIST_HEAD(&hdev->uuids); INIT_LIST_HEAD(&hdev->link_keys); INIT_LIST_HEAD(&hdev->long_term_keys); diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index b9186026508e..0908eaa7cacf 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -2505,6 +2505,7 @@ static void hci_inquiry_result_evt(struct hci_dev *hdev, struct sk_buff *skb) static void hci_conn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb) { struct hci_ev_conn_complete *ev = (void *) skb->data; + struct inquiry_entry *ie; struct hci_conn *conn; BT_DBG("%s", hdev->name); @@ -2513,6 +2514,21 @@ static void hci_conn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb) conn = hci_conn_hash_lookup_ba(hdev, ev->link_type, &ev->bdaddr); if (!conn) { + /* Connection may not exist if auto-connected. Check the inquiry + * cache to see if we've already discovered this bdaddr before. + * If found and link is an ACL type, create a connection class + * automatically. + */ + ie = hci_inquiry_cache_lookup(hdev, &ev->bdaddr); + if (ie && ev->link_type == ACL_LINK) { + conn = hci_conn_add(hdev, ev->link_type, &ev->bdaddr, + HCI_ROLE_SLAVE); + if (!conn) { + bt_dev_err(hdev, "no memory for new conn"); + goto unlock; + } + } + if (ev->link_type != SCO_LINK) goto unlock; @@ -2774,6 +2790,14 @@ static void hci_disconn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb) hci_disconn_cfm(conn, ev->reason); hci_conn_del(conn); + /* The suspend notifier is waiting for all devices to disconnect so + * clear the bit from pending tasks and inform the wait queue. + */ + if (list_empty(&hdev->conn_hash.list) && + test_and_clear_bit(SUSPEND_DISCONNECTING, hdev->suspend_tasks)) { + wake_up(&hdev->suspend_wait_q); + } + /* Re-enable advertising if necessary, since it might * have been disabled by the connection. From the * HCI_LE_Set_Advertise_Enable command description in diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c index 2343166614f0..051e1b16c988 100644 --- a/net/bluetooth/hci_request.c +++ b/net/bluetooth/hci_request.c @@ -918,15 +918,118 @@ static u8 get_adv_instance_scan_rsp_len(struct hci_dev *hdev, u8 instance) return adv_instance->scan_rsp_len; } +static void hci_req_clear_event_filter(struct hci_request *req) +{ + struct hci_cp_set_event_filter f; + + memset(&f, 0, sizeof(f)); + f.flt_type = HCI_FLT_CLEAR_ALL; + hci_req_add(req, HCI_OP_SET_EVENT_FLT, 1, &f); + + /* Update page scan state (since we may have modified it when setting + * the event filter). + */ + __hci_req_update_scan(req); +} + +static void hci_req_set_event_filter(struct hci_request *req) +{ + struct bdaddr_list *b; + struct hci_cp_set_event_filter f; + struct hci_dev *hdev = req->hdev; + u8 scan; + + /* Always clear event filter when starting */ + hci_req_clear_event_filter(req); + + list_for_each_entry(b, &hdev->wakeable, list) { + memset(&f, 0, sizeof(f)); + bacpy(&f.addr_conn_flt.bdaddr, &b->bdaddr); + f.flt_type = HCI_FLT_CONN_SETUP; + f.cond_type = HCI_CONN_SETUP_ALLOW_BDADDR; + f.addr_conn_flt.auto_accept = HCI_CONN_SETUP_AUTO_ON; + + bt_dev_dbg(hdev, "Adding event filters for %pMR", &b->bdaddr); + hci_req_add(req, HCI_OP_SET_EVENT_FLT, sizeof(f), &f); + } + + scan = !list_empty(&hdev->wakeable) ? SCAN_PAGE : SCAN_DISABLED; + hci_req_add(req, HCI_OP_WRITE_SCAN_ENABLE, 1, &scan); +} + +static void suspend_req_complete(struct hci_dev *hdev, u8 status, u16 opcode) +{ + bt_dev_dbg(hdev, "Request complete opcode=0x%x, status=0x%x", opcode, + status); + if (test_and_clear_bit(SUSPEND_SCAN_ENABLE, hdev->suspend_tasks) || + test_and_clear_bit(SUSPEND_SCAN_DISABLE, hdev->suspend_tasks)) { + wake_up(&hdev->suspend_wait_q); + } +} + /* Call with hci_dev_lock */ void hci_req_prepare_suspend(struct hci_dev *hdev, enum suspended_state next) { + struct hci_conn *conn; + struct hci_request req; + u8 page_scan; + int disconnect_counter; + if (next == hdev->suspend_state) { bt_dev_dbg(hdev, "Same state before and after: %d", next); goto done; } hdev->suspend_state = next; + hci_req_init(&req, hdev); + + if (next == BT_SUSPEND_DISCONNECT) { + /* Mark device as suspended */ + hdev->suspended = true; + + /* Disable page scan */ + page_scan = SCAN_DISABLED; + hci_req_add(&req, HCI_OP_WRITE_SCAN_ENABLE, 1, &page_scan); + + /* Mark task needing completion */ + set_bit(SUSPEND_SCAN_DISABLE, hdev->suspend_tasks); + + /* Prevent disconnects from causing scanning to be re-enabled */ + hdev->scanning_paused = true; + + /* Run commands before disconnecting */ + hci_req_run(&req, suspend_req_complete); + + disconnect_counter = 0; + /* Soft disconnect everything (power off) */ + list_for_each_entry(conn, &hdev->conn_hash.list, list) { + hci_disconnect(conn, HCI_ERROR_REMOTE_POWER_OFF); + disconnect_counter++; + } + + if (disconnect_counter > 0) { + bt_dev_dbg(hdev, + "Had %d disconnects. Will wait on them", + disconnect_counter); + set_bit(SUSPEND_DISCONNECTING, hdev->suspend_tasks); + } + } else if (next == BT_SUSPEND_COMPLETE) { + /* Unpause to take care of updating scanning params */ + hdev->scanning_paused = false; + /* Enable event filter for paired devices */ + hci_req_set_event_filter(&req); + /* Pause scan changes again. */ + hdev->scanning_paused = true; + hci_req_run(&req, suspend_req_complete); + } else { + hdev->suspended = false; + hdev->scanning_paused = false; + + hci_req_clear_event_filter(&req); + hci_req_run(&req, suspend_req_complete); + } + + hdev->suspend_state = next; done: clear_bit(SUSPEND_PREPARE_NOTIFIER, hdev->suspend_tasks); @@ -2030,6 +2133,9 @@ void __hci_req_update_scan(struct hci_request *req) if (mgmt_powering_down(hdev)) return; + if (hdev->scanning_paused) + return; + if (hci_dev_test_flag(hdev, HCI_CONNECTABLE) || disconnected_whitelist_entries(hdev)) scan = SCAN_PAGE; -- cgit v1.2.1