Bluetooth: Add support for setting LE advertising data

This patch adds support for setting basing LE advertising data. The
three elements supported for now are the advertising flags, the TX power
and the friendly name.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

4 files changed, 123 insertions, 1 deletions

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 344fea0a7244..7306078e547c 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -338,6 +338,13 @@ enum {
 #define EIR_SSP_RAND_R          0x0F /* Simple Pairing Randomizer R */
 #define EIR_DEVICE_ID           0x10 /* device ID */
 
+/* Low Energy Advertising Flags */
+#define LE_AD_LIMITED           0x01 /* Limited Discoverable */
+#define LE_AD_GENERAL           0x02 /* General Discoverable */
+#define LE_AD_NO_BREDR          0x04 /* BR/EDR not supported */
+#define LE_AD_SIM_LE_BREDR_CTRL 0x08 /* Simultaneous LE & BR/EDR Controller */
+#define LE_AD_SIM_LE_BREDR_HOST 0x10 /* Simultaneous LE & BR/EDR Host */
+
 /* -----  HCI Commands ---- */
 #define HCI_OP_NOP                      0x0000
 
@@ -942,6 +949,14 @@ struct hci_rp_le_read_adv_tx_power {
         __s8    tx_power;
 } __packed;
 
+#define HCI_MAX_AD_LENGTH               31
+
+#define HCI_OP_LE_SET_ADV_DATA          0x2008
+struct hci_cp_le_set_adv_data {
+        __u8    length;
+        __u8    data[HCI_MAX_AD_LENGTH];
+} __packed;
+
 #define HCI_OP_LE_SET_SCAN_PARAM        0x200b
 struct hci_cp_le_set_scan_param {
         __u8    type;
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index ce6dbeb6dfb6..ef5b85dac3f7 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -279,6 +279,8 @@ struct hci_dev {
         struct le_scan_params   le_scan_params;
 
         __s8                    adv_tx_power;
+        __u8                    adv_data[HCI_MAX_AD_LENGTH];
+        __u8                    adv_data_len;
 
         int (*open)(struct hci_dev *hdev);
         int (*close)(struct hci_dev *hdev);
@@ -734,6 +736,8 @@ int hci_add_remote_oob_data(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 *hash,
                                                                 u8 *randomizer);
 int hci_remove_remote_oob_data(struct hci_dev *hdev, bdaddr_t *bdaddr);
 
+int hci_update_ad(struct hci_dev *hdev);
+
 void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb);
 
 int hci_recv_frame(struct sk_buff *skb);
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 9713a2917ddc..e3a49db9cfcb 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -594,6 +594,99 @@ done:
         return err;
 }
 
+static u8 create_ad(struct hci_dev *hdev, u8 *ptr)
+{
+        u8 ad_len = 0, flags = 0;
+        size_t name_len;
+
+        if (test_bit(HCI_LE_PERIPHERAL, &hdev->dev_flags))
+                flags |= LE_AD_GENERAL;
+
+        if (!lmp_bredr_capable(hdev))
+                flags |= LE_AD_NO_BREDR;
+
+        if (lmp_le_br_capable(hdev))
+                flags |= LE_AD_SIM_LE_BREDR_CTRL;
+
+        if (lmp_host_le_br_capable(hdev))
+                flags |= LE_AD_SIM_LE_BREDR_HOST;
+
+        if (flags) {
+                BT_DBG("adv flags 0x%02x", flags);
+
+                ptr[0] = 2;
+                ptr[1] = EIR_FLAGS;
+                ptr[2] = flags;
+
+                ad_len += 3;
+                ptr += 3;
+        }
+
+        if (hdev->adv_tx_power != HCI_TX_POWER_INVALID) {
+                ptr[0] = 2;
+                ptr[1] = EIR_TX_POWER;
+                ptr[2] = (u8) hdev->adv_tx_power;
+
+                ad_len += 3;
+                ptr += 3;
+        }
+
+        name_len = strlen(hdev->dev_name);
+        if (name_len > 0) {
+                size_t max_len = HCI_MAX_AD_LENGTH - ad_len - 2;
+
+                if (name_len > max_len) {
+                        name_len = max_len;
+                        ptr[1] = EIR_NAME_SHORT;
+                } else
+                        ptr[1] = EIR_NAME_COMPLETE;
+
+                ptr[0] = name_len + 1;
+
+                memcpy(ptr + 2, hdev->dev_name, name_len);
+
+                ad_len += (name_len + 2);
+                ptr += (name_len + 2);
+        }
+
+        return ad_len;
+}
+
+int hci_update_ad(struct hci_dev *hdev)
+{
+        struct hci_cp_le_set_adv_data cp;
+        u8 len;
+        int err;
+
+        hci_dev_lock(hdev);
+
+        if (!lmp_le_capable(hdev)) {
+                err = -EINVAL;
+                goto unlock;
+        }
+
+        memset(&cp, 0, sizeof(cp));
+
+        len = create_ad(hdev, cp.data);
+
+        if (hdev->adv_data_len == len &&
+            memcmp(cp.data, hdev->adv_data, len) == 0) {
+                err = 0;
+                goto unlock;
+        }
+
+        memcpy(hdev->adv_data, cp.data, sizeof(cp.data));
+        hdev->adv_data_len = len;
+
+        cp.length = len;
+        err = hci_send_cmd(hdev, HCI_OP_LE_SET_ADV_DATA, sizeof(cp), &cp);
+
+unlock:
+        hci_dev_unlock(hdev);
+
+        return err;
+}
+
 /* ---- HCI ioctl helpers ---- */
 
 int hci_dev_open(__u16 dev)
@@ -651,6 +744,7 @@ int hci_dev_open(__u16 dev)
                 hci_dev_hold(hdev);
                 set_bit(HCI_UP, &hdev->flags);
                 hci_notify(hdev, HCI_DEV_UP);
+                hci_update_ad(hdev);
                 if (!test_bit(HCI_SETUP, &hdev->dev_flags) &&
                     mgmt_valid_hdev(hdev)) {
                         hci_dev_lock(hdev);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 09c65712e8cc..7caea1af557b 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -204,6 +204,9 @@ static void hci_cc_reset(struct hci_dev *hdev, struct sk_buff *skb)
         hdev->discovery.state = DISCOVERY_STOPPED;
         hdev->inq_tx_power = HCI_TX_POWER_INVALID;
         hdev->adv_tx_power = HCI_TX_POWER_INVALID;
+
+        memset(hdev->adv_data, 0, sizeof(hdev->adv_data));
+        hdev->adv_data_len = 0;
 }
 
 static void hci_cc_write_local_name(struct hci_dev *hdev, struct sk_buff *skb)
@@ -226,6 +229,9 @@ static void hci_cc_write_local_name(struct hci_dev *hdev, struct sk_buff *skb)
 
         hci_dev_unlock(hdev);
 
+        if (!status && !test_bit(HCI_INIT, &hdev->flags))
+                hci_update_ad(hdev);
+
         hci_req_complete(hdev, HCI_OP_WRITE_LOCAL_NAME, status);
 }
 
@@ -1091,8 +1097,11 @@ static void hci_cc_le_read_adv_tx_power(struct hci_dev *hdev,
 
         BT_DBG("%s status 0x%2.2x", hdev->name, rp->status);
 
-        if (!rp->status)
+        if (!rp->status) {
                 hdev->adv_tx_power = rp->tx_power;
+                if (!test_bit(HCI_INIT, &hdev->flags))
+                        hci_update_ad(hdev);
+        }
 
         hci_req_complete(hdev, HCI_OP_LE_READ_ADV_TX_POWER, rp->status);
 }