2011-06-15 21:12:20

by Anderson Briglia

[permalink] [raw]
Subject: [RFC 1/2] Bluetooth: Implement Read RSSI command

From: Anderson Briglia <[email protected]>

This patch implements helper functions to make Read RSSI command
interceptable by Management Interface. It adds a new wrapper in HCI
layer and add a hook to call mgmt_read_rssi_complete when MGMT Interface
has been loaded.

Read RSSI command is defined on Part E, section 7.5.4 of Bluetooth 4.0
Spec.

Signed-off-by: Anderson Briglia <[email protected]>
---
include/net/bluetooth/hci.h | 10 ++++
include/net/bluetooth/hci_core.h | 2 +
include/net/bluetooth/mgmt.h | 10 ++++
net/bluetooth/hci_event.c | 24 +++++++++
net/bluetooth/mgmt.c | 99 ++++++++++++++++++++++++++++++++++++++
5 files changed, 145 insertions(+), 0 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 0f04c42..ba6a4f8 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -545,6 +545,16 @@ struct hci_cp_set_event_flt {
__u8 condition[0];
} __packed;

+#define HCI_OP_READ_RSSI 0x1405
+struct hci_cp_read_rssi {
+ __le16 handle;
+} __packed;
+struct hci_rp_read_rssi {
+ __u8 status;
+ __le16 handle;
+ __s8 rssi;
+} __packed;
+
/* Filter types */
#define HCI_FLT_CLEAR_ALL 0x00
#define HCI_FLT_INQ_RESULT 0x01
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 5a7aa74..18e13f5 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -840,6 +840,8 @@ int mgmt_auth_failed(u16 index, bdaddr_t *bdaddr, u8 status);
int mgmt_set_local_name_complete(u16 index, u8 *name, u8 status);
int mgmt_read_local_oob_data_reply_complete(u16 index, u8 *hash, u8 *randomizer,
u8 status);
+int mgmt_read_rssi_complete(u16 index, bdaddr_t *bdaddr, s8 rssi, u8 status);
+int mgmt_read_rssi_failed(u16 index);
int mgmt_device_found(u16 index, bdaddr_t *bdaddr, u8 *dev_class, s8 rssi,
u8 *eir, u8 eir_len);
int mgmt_remote_name(u16 index, bdaddr_t *bdaddr, u8 *name);
diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 9663f5d..d71f648 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -201,6 +201,16 @@ struct mgmt_cp_remove_remote_oob_data {

#define MGMT_OP_STOP_DISCOVERY 0x001C

+#define MGMT_OP_READ_RSSI 0x001D
+struct mgmt_cp_read_rssi {
+ bdaddr_t bdaddr;
+} __packed;
+struct mgmt_rp_read_rssi {
+ __u8 status;
+ bdaddr_t bdaddr;
+ __s8 rssi;
+} __packed;
+
#define MGMT_EV_CMD_COMPLETE 0x0001
struct mgmt_ev_cmd_complete {
__le16 opcode;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index a4cd22b..02a32e9 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -900,6 +900,26 @@ static void hci_cc_le_ltk_neg_reply(struct hci_dev *hdev, struct sk_buff *skb)
hci_req_complete(hdev, HCI_OP_LE_LTK_NEG_REPLY, rp->status);
}

+static void hci_cc_read_rssi(struct hci_dev *hdev, struct sk_buff *skb)
+{
+ struct hci_rp_read_rssi *rp = (void *) skb->data;
+ struct hci_conn *conn;
+
+ BT_DBG("%s status 0x%x", hdev->name, rp->status);
+
+ if (!test_bit(HCI_MGMT, &hdev->flags))
+ return;
+
+ conn = hci_conn_hash_lookup_handle(hdev, __le16_to_cpu(rp->handle));
+ if (!conn) {
+ mgmt_read_rssi_failed(hdev->id);
+ return;
+ }
+
+ mgmt_read_rssi_complete(hdev->id, &conn->dst, rp->rssi,
+ rp->status);
+}
+
static inline void hci_cs_inquiry(struct hci_dev *hdev, __u8 status)
{
BT_DBG("%s status 0x%x", hdev->name, status);
@@ -1905,6 +1925,10 @@ static inline void hci_cmd_complete_evt(struct hci_dev *hdev, struct sk_buff *sk
hci_cc_le_ltk_neg_reply(hdev, skb);
break;

+ case HCI_OP_READ_RSSI:
+ hci_cc_read_rssi(hdev, skb);
+ break;
+
default:
BT_DBG("%s opcode 0x%x", hdev->name, opcode);
break;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index cbc922a..ab37958 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -1637,6 +1637,102 @@ static int remove_remote_oob_data(struct sock *sk, u16 index,
return err;
}

+static int read_rssi(struct sock *sk, u16 index, unsigned char *data, u16 len)
+{
+ struct hci_dev *hdev;
+ struct mgmt_cp_read_rssi *cp = (void *) data;
+ struct hci_cp_read_rssi rs;
+ struct hci_conn *conn;
+ struct pending_cmd *cmd;
+ int err;
+
+ BT_DBG("hci%u", index);
+
+ if (len != sizeof(*cp))
+ return cmd_status(sk, index, MGMT_OP_READ_RSSI, EINVAL);
+
+ hdev = hci_dev_get(index);
+ if (!hdev)
+ return cmd_status(sk, index, MGMT_OP_READ_RSSI, ENODEV);
+
+ hci_dev_lock(hdev);
+
+ if (!test_bit(HCI_UP, &hdev->flags)) {
+ err = cmd_status(sk, index, MGMT_OP_READ_RSSI, ENETDOWN);
+ goto unlock;
+ }
+
+ if (mgmt_pending_find(MGMT_OP_READ_RSSI, index)) {
+ err = cmd_status(sk, index, MGMT_OP_READ_RSSI, EBUSY);
+ goto unlock;
+ }
+
+ cmd = mgmt_pending_add(sk, MGMT_OP_READ_RSSI, index, NULL, 0);
+ if (!cmd) {
+ err = -ENOMEM;
+ goto unlock;
+ }
+
+ conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &cp->bdaddr);
+ if (!conn)
+ conn = hci_conn_hash_lookup_ba(hdev, LE_LINK, &cp->bdaddr);
+
+ if (!conn) {
+ err = cmd_status(sk, index, MGMT_OP_READ_RSSI, ENOTCONN);
+ goto unlock;
+ }
+
+ put_unaligned_le16(conn->handle, &rs.handle);
+
+ err = hci_send_cmd(hdev, HCI_OP_READ_RSSI, sizeof(rs), &rs);
+ if (err < 0)
+ mgmt_pending_remove(cmd);
+
+unlock:
+ hci_dev_unlock(hdev);
+ hci_dev_put(hdev);
+
+ return err;
+}
+
+int mgmt_read_rssi_failed(u16 index)
+{
+ struct pending_cmd *cmd;
+ int err = 0;
+
+ cmd = mgmt_pending_find(MGMT_OP_READ_RSSI, index);
+ if (!cmd)
+ return -ENOENT;
+
+ err = cmd_status(cmd->sk, index, MGMT_OP_READ_RSSI, EIO);
+
+ mgmt_pending_remove(cmd);
+
+ return err;
+}
+
+int mgmt_read_rssi_complete(u16 index, bdaddr_t *bdaddr, s8 rssi, u8 status)
+{
+ struct pending_cmd *cmd;
+ struct mgmt_rp_read_rssi rp;
+ int err;
+
+ cmd = mgmt_pending_find(MGMT_OP_READ_RSSI, index);
+ if (!cmd)
+ return -ENOENT;
+
+ bacpy(&rp.bdaddr, bdaddr);
+ rp.status = status;
+ rp.rssi = rssi;
+
+ err = cmd_complete(cmd->sk, index, MGMT_OP_READ_RSSI, &rp,
+ sizeof(rp));
+
+ mgmt_pending_remove(cmd);
+
+ return err;
+}
+
static int start_inquiry(struct hci_dev *hdev, __u8 inq_length)
{
u8 lap[3] = { 0x33, 0x8b, 0x9e };
@@ -1944,6 +2040,9 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
case MGMT_OP_STOP_DISCOVERY:
err = stop_discovery(sk, index);
break;
+ case MGMT_OP_READ_RSSI:
+ err = read_rssi(sk, index, buf + sizeof(*hdr), len);
+ break;
default:
BT_DBG("Unknown op %u", opcode);
err = cmd_status(sk, index, opcode, 0x01);
--
1.7.4.1