Revert "Revert "CHROMIUM: bluetooth: reset advertising intervals""

This reverts commit f6794e6d752ddd9c183ecd7a3b3f4ef960fe7c99.

BUG=chromium:704196
TEST=Deploy v5.44 BlueZ system daemon with v4.9 BlueZ kernel on Nyan_Big and
perform automated tests (suite:bluetooth) and manual tests against mouses,
keyboards and headphones.

Change-Id: I63f79f7d7927faf34bfd7231488c2813f10011e2
Signed-off-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/480214
Tested-by: Shyh-In Hwang <josephsih@chromium.org>
Reviewed-by: Shyh-In Hwang <josephsih@chromium.org>

net/bluetooth/mgmt.c

@@ -4361,6 +4361,8 @@ static int set_advertising_intervals(struct sock *sk, struct hci_dev *hdev,
 {
 	struct mgmt_cp_set_advertising_intervals *cp = data;
 	int err;
+	/* If both min_interval and max_interval are 0, use default values. */
+	bool use_default = cp->min_interval == 0 && cp->max_interval == 0;
 
 	BT_DBG("%s", hdev->name);
 
@@ -4371,19 +4373,25 @@ static int set_advertising_intervals(struct sock *sk, struct hci_dev *hdev,
 				       MGMT_STATUS_REJECTED);
 
 	/* Check the validity of the intervals. */
-	if (cp->min_interval < HCI_VALID_LE_ADV_MIN_INTERVAL ||
-	    cp->max_interval > HCI_VALID_LE_ADV_MAX_INTERVAL ||
-	    cp->min_interval > cp->max_interval) {
+	if (!use_default && (cp->min_interval < HCI_VALID_LE_ADV_MIN_INTERVAL ||
+			     cp->max_interval > HCI_VALID_LE_ADV_MAX_INTERVAL ||
+			     cp->min_interval > cp->max_interval)) {
 		return mgmt_cmd_status(sk, hdev->id,
 				       MGMT_OP_SET_ADVERTISING_INTERVALS,
 				       MGMT_STATUS_INVALID_PARAMS);
 	}
 
 	hci_dev_lock(hdev);
 
-	hci_dev_set_flag(hdev, HCI_ADVERTISING_INTERVALS);
-	hdev->le_adv_min_interval = cp->min_interval;
-	hdev->le_adv_max_interval = cp->max_interval;
+	if (use_default) {
+		hci_dev_clear_flag(hdev, HCI_ADVERTISING_INTERVALS);
+		hdev->le_adv_min_interval = HCI_DEFAULT_LE_ADV_MIN_INTERVAL;
+		hdev->le_adv_max_interval = HCI_DEFAULT_LE_ADV_MAX_INTERVAL;
+	} else {
+		hci_dev_set_flag(hdev, HCI_ADVERTISING_INTERVALS);
+		hdev->le_adv_min_interval = cp->min_interval;
+		hdev->le_adv_max_interval = cp->max_interval;
+	}
 
 	/* Re-enable advertising only when it is already on. */
 	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {