Bluetooth: Add BT_POWER L2CAP socket option.
Add BT_POWER socket option used to control the power
characteristics of the underlying ACL link. When the remote end
has put the link in sniff mode and the host stack wants to send
data we need need to explicitly exit sniff mode to work well with
certain devices (For example, A2DP on Plantronics Voyager 855).
However, this causes problems with HID devices.
Hence, moving into active mode when sending data, irrespective
of who set the sniff mode has been made as a socket option. By
default, we will move into active mode. HID devices can set the
L2CAP socket option to prevent this from happening.
Currently, this has been implemented for L2CAP sockets. This has been
tested with incoming and outgoing L2CAP sockets for HID and A2DP.
Based on discussions on linux-bluetooth and patches submitted by
Andrei Emeltchenko.
Signed-off-by: Jaikumar Ganesh <jaikumar@google.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index ce67d0f..0408a93 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -507,7 +507,7 @@
if (acl->state == BT_CONNECTED &&
(sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
acl->power_save = 1;
- hci_conn_enter_active_mode(acl);
+ hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->pend)) {
/* defer SCO setup until mode change completed */
@@ -688,7 +688,7 @@
EXPORT_SYMBOL(hci_conn_switch_role);
/* Enter active mode */
-void hci_conn_enter_active_mode(struct hci_conn *conn)
+void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
{
struct hci_dev *hdev = conn->hdev;
@@ -697,7 +697,10 @@
if (test_bit(HCI_RAW, &hdev->flags))
return;
- if (conn->mode != HCI_CM_SNIFF || !conn->power_save)
+ if (conn->mode != HCI_CM_SNIFF)
+ goto timer;
+
+ if (!conn->power_save && !force_active)
goto timer;
if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->pend)) {
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index ff6b784..e14e8a1 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1969,7 +1969,7 @@
while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
BT_DBG("skb %p len %d", skb, skb->len);
- hci_conn_enter_active_mode(conn);
+ hci_conn_enter_active_mode(conn, bt_cb(skb)->force_active);
hci_send_frame(skb);
hdev->acl_last_tx = jiffies;
@@ -2108,7 +2108,7 @@
if (conn) {
register struct hci_proto *hp;
- hci_conn_enter_active_mode(conn);
+ hci_conn_enter_active_mode(conn, bt_cb(skb)->force_active);
/* Send to upper protocol */
hp = hci_proto[HCI_PROTO_L2CAP];
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index bb6be63..6908a83 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -537,6 +537,8 @@
else
flags = ACL_START;
+ bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
+
hci_send_acl(conn->hcon, skb, flags);
}
@@ -590,6 +592,8 @@
else
flags = ACL_START;
+ bt_cb(skb)->force_active = chan->force_active;
+
hci_send_acl(chan->conn->hcon, skb, flags);
}
@@ -1215,6 +1219,7 @@
else
flags = ACL_START;
+ bt_cb(skb)->force_active = chan->force_active;
hci_send_acl(hcon, skb, flags);
}
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index b79fb75..bec3e04 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -390,6 +390,7 @@
struct sock *sk = sock->sk;
struct l2cap_chan *chan = l2cap_pi(sk)->chan;
struct bt_security sec;
+ struct bt_power pwr;
int len, err = 0;
BT_DBG("sk %p", sk);
@@ -438,6 +439,21 @@
break;
+ case BT_POWER:
+ if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
+ && sk->sk_type != SOCK_RAW) {
+ err = -EINVAL;
+ break;
+ }
+
+ pwr.force_active = chan->force_active;
+
+ len = min_t(unsigned int, len, sizeof(pwr));
+ if (copy_to_user(optval, (char *) &pwr, len))
+ err = -EFAULT;
+
+ break;
+
default:
err = -ENOPROTOOPT;
break;
@@ -538,6 +554,7 @@
struct sock *sk = sock->sk;
struct l2cap_chan *chan = l2cap_pi(sk)->chan;
struct bt_security sec;
+ struct bt_power pwr;
int len, err = 0;
u32 opt;
@@ -614,6 +631,23 @@
chan->flushable = opt;
break;
+ case BT_POWER:
+ if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
+ chan->chan_type != L2CAP_CHAN_RAW) {
+ err = -EINVAL;
+ break;
+ }
+
+ pwr.force_active = BT_POWER_FORCE_ACTIVE_ON;
+
+ len = min_t(unsigned int, sizeof(pwr), optlen);
+ if (copy_from_user((char *) &pwr, optval, len)) {
+ err = -EFAULT;
+ break;
+ }
+ chan->force_active = pwr.force_active;
+ break;
+
default:
err = -ENOPROTOOPT;
break;
@@ -771,6 +805,7 @@
chan->role_switch = pchan->role_switch;
chan->force_reliable = pchan->force_reliable;
chan->flushable = pchan->flushable;
+ chan->force_active = pchan->force_active;
} else {
switch (sk->sk_type) {
@@ -801,6 +836,7 @@
chan->role_switch = 0;
chan->force_reliable = 0;
chan->flushable = BT_FLUSHABLE_OFF;
+ chan->force_active = BT_POWER_FORCE_ACTIVE_ON;
}
/* Default config options */