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 <jpawlowski@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Jakub Pawlowski 2015-02-01 23:07:54 -08:00 committed by Marcel Holtmann
parent 3251ca334b
commit 2d28cfe7aa
3 changed files with 97 additions and 1 deletions

View File

@ -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);

View File

@ -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);

View File

@ -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);