From 2d28cfe7aada495f87bb439151e9bcc86998fb6d Mon Sep 17 00:00:00 2001 From: Jakub Pawlowski Date: Sun, 1 Feb 2015 23:07:54 -0800 Subject: [PATCH] Bluetooth: Add le_scan_restart work for LE scan restarting Currently there is no way to restart le scan, and it's needed in service scan method. The way it work: it disable, and then enable le scan on controller. During the restart, we must remember when the scan was started, and it's duration, to later re-schedule the le_scan_disable work, that was stopped during the stop scan phase. Signed-off-by: Jakub Pawlowski Signed-off-by: Marcel Holtmann --- include/net/bluetooth/hci_core.h | 5 +++ net/bluetooth/hci_core.c | 74 ++++++++++++++++++++++++++++++++++++++++ net/bluetooth/mgmt.c | 19 ++++++++++- 3 files changed, 97 insertions(+), 1 deletion(-) diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index a37e10f..d3a232b 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -79,6 +79,8 @@ struct discovery_state { s8 rssi; u16 uuid_count; u8 (*uuids)[16]; + unsigned long scan_start; + unsigned long scan_duration; }; struct hci_conn_hash { @@ -354,6 +356,7 @@ struct hci_dev { unsigned long dev_flags; struct delayed_work le_scan_disable; + struct delayed_work le_scan_restart; __s8 adv_tx_power; __u8 adv_data[HCI_MAX_AD_LENGTH]; @@ -531,6 +534,8 @@ static inline void hci_discovery_filter_clear(struct hci_dev *hdev) hdev->discovery.uuid_count = 0; kfree(hdev->discovery.uuids); hdev->discovery.uuids = NULL; + hdev->discovery.scan_start = 0; + hdev->discovery.scan_duration = 0; } bool hci_discovery_active(struct hci_dev *hdev); diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index f045c06..3322d3f 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -1617,6 +1617,7 @@ static int hci_dev_do_close(struct hci_dev *hdev) cancel_delayed_work(&hdev->service_cache); cancel_delayed_work_sync(&hdev->le_scan_disable); + cancel_delayed_work_sync(&hdev->le_scan_restart); if (test_bit(HCI_MGMT, &hdev->dev_flags)) cancel_delayed_work_sync(&hdev->rpa_expired); @@ -2830,6 +2831,8 @@ static void le_scan_disable_work_complete(struct hci_dev *hdev, u8 status, return; } + hdev->discovery.scan_start = 0; + switch (hdev->discovery.type) { case DISCOV_TYPE_LE: hci_dev_lock(hdev); @@ -2869,6 +2872,8 @@ static void le_scan_disable_work(struct work_struct *work) BT_DBG("%s", hdev->name); + cancel_delayed_work_sync(&hdev->le_scan_restart); + hci_req_init(&req, hdev); hci_req_add_le_scan_disable(&req); @@ -2878,6 +2883,74 @@ static void le_scan_disable_work(struct work_struct *work) BT_ERR("Disable LE scanning request failed: err %d", err); } +static void le_scan_restart_work_complete(struct hci_dev *hdev, u8 status, + u16 opcode) +{ + unsigned long timeout, duration, scan_start, now; + + BT_DBG("%s", hdev->name); + + if (status) { + BT_ERR("Failed to restart LE scan: status %d", status); + return; + } + + if (!test_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks) || + !hdev->discovery.scan_start) + return; + + /* When the scan was started, hdev->le_scan_disable has been queued + * after duration from scan_start. During scan restart this job + * has been canceled, and we need to queue it again after proper + * timeout, to make sure that scan does not run indefinitely. + */ + duration = hdev->discovery.scan_duration; + scan_start = hdev->discovery.scan_start; + now = jiffies; + if (now - scan_start <= duration) { + int elapsed; + + if (now >= scan_start) + elapsed = now - scan_start; + else + elapsed = ULONG_MAX - scan_start + now; + + timeout = duration - elapsed; + } else { + timeout = 0; + } + queue_delayed_work(hdev->workqueue, + &hdev->le_scan_disable, timeout); +} + +static void le_scan_restart_work(struct work_struct *work) +{ + struct hci_dev *hdev = container_of(work, struct hci_dev, + le_scan_restart.work); + struct hci_request req; + struct hci_cp_le_set_scan_enable cp; + int err; + + BT_DBG("%s", hdev->name); + + /* If controller is not scanning we are done. */ + if (!test_bit(HCI_LE_SCAN, &hdev->dev_flags)) + return; + + hci_req_init(&req, hdev); + + hci_req_add_le_scan_disable(&req); + + memset(&cp, 0, sizeof(cp)); + cp.enable = LE_SCAN_ENABLE; + cp.filter_dup = LE_SCAN_FILTER_DUP_ENABLE; + hci_req_add(&req, HCI_OP_LE_SET_SCAN_ENABLE, sizeof(cp), &cp); + + err = hci_req_run(&req, le_scan_restart_work_complete); + if (err) + BT_ERR("Restart LE scan request failed: err %d", err); +} + /* Copy the Identity Address of the controller. * * If the controller has a public BD_ADDR, then by default use that one. @@ -2974,6 +3047,7 @@ struct hci_dev *hci_alloc_dev(void) INIT_DELAYED_WORK(&hdev->power_off, hci_power_off); INIT_DELAYED_WORK(&hdev->discov_off, hci_discov_off); INIT_DELAYED_WORK(&hdev->le_scan_disable, le_scan_disable_work); + INIT_DELAYED_WORK(&hdev->le_scan_restart, le_scan_restart_work); skb_queue_head_init(&hdev->rx_q); skb_queue_head_init(&hdev->cmd_q); diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index ba3b4a58..8c2520a 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -3896,6 +3896,9 @@ static void start_discovery_complete(struct hci_dev *hdev, u8 status, hci_discovery_set_state(hdev, DISCOVERY_FINDING); + /* If the scan involves LE scan, pick proper timeout to schedule + * hdev->le_scan_disable that will stop it. + */ switch (hdev->discovery.type) { case DISCOV_TYPE_LE: timeout = msecs_to_jiffies(DISCOV_LE_TIMEOUT); @@ -3912,9 +3915,23 @@ static void start_discovery_complete(struct hci_dev *hdev, u8 status, break; } - if (timeout) + if (timeout) { + /* When service discovery is used and the controller has + * a strict duplicate filter, it is important to remember + * the start and duration of the scan. This is required + * for restarting scanning during the discovery phase. + */ + if (test_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, + &hdev->quirks) && + (hdev->discovery.uuid_count > 0 || + hdev->discovery.rssi != HCI_RSSI_INVALID)) { + hdev->discovery.scan_start = jiffies; + hdev->discovery.scan_duration = timeout; + } + queue_delayed_work(hdev->workqueue, &hdev->le_scan_disable, timeout); + } unlock: hci_dev_unlock(hdev); -- 2.7.4