[PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Jaikumar Ganesh]

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>
---
 include/net/bluetooth/bluetooth.h |    8 ++++++++
 include/net/bluetooth/hci_core.h  |    2 +-
 include/net/bluetooth/l2cap.h     |    1 +
 net/bluetooth/hci_conn.c          |    9 ++++++---
 net/bluetooth/hci_core.c          |    4 ++--
 net/bluetooth/l2cap_core.c        |    5 +++++
 net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
 7 files changed, 59 insertions(+), 6 deletions(-)

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 4375043..af930a3 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -69,6 +69,13 @@ struct bt_security {
 #define BT_FLUSHABLE_OFF	0
 #define BT_FLUSHABLE_ON		1
 
+#define BT_POWER	9
+struct bt_power {
+	__u8 force_active;
+};
+#define BT_POWER_FORCE_ACTIVE_OFF 0
+#define BT_POWER_FORCE_ACTIVE_ON  1
+
 #define BT_INFO(fmt, arg...) printk(KERN_INFO "Bluetooth: " fmt "\n" , ## arg)
 #define BT_ERR(fmt, arg...)  printk(KERN_ERR "%s: " fmt "\n" , __func__ , ## arg)
 #define BT_DBG(fmt, arg...)  pr_debug("%s: " fmt "\n" , __func__ , ## arg)
@@ -150,6 +157,7 @@ struct bt_skb_cb {
 	__u8 retries;
 	__u8 sar;
 	unsigned short channel;
+	__u8 force_active;
 };
 #define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))
 
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6c994c0..0747841 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -427,7 +427,7 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
 int hci_conn_change_link_key(struct hci_conn *conn);
 int hci_conn_switch_role(struct hci_conn *conn, __u8 role);
 
-void hci_conn_enter_active_mode(struct hci_conn *conn);
+void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active);
 void hci_conn_enter_sniff_mode(struct hci_conn *conn);
 
 void hci_conn_hold_device(struct hci_conn *conn);
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index d09c9b1..942970d 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -302,6 +302,7 @@ struct l2cap_chan {
 	__u8		role_switch;
 	__u8		force_reliable;
 	__u8		flushable;
+	__u8		force_active;
 
 	__u8		ident;
 
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 3163330..5195715 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -497,7 +497,7 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8
 	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 */
@@ -676,7 +676,7 @@ int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
 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;
 
@@ -685,7 +685,10 @@ void hci_conn_enter_active_mode(struct hci_conn *conn)
 	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 b6bda3f..be68e7d 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1893,7 +1893,7 @@ static inline void hci_sched_acl(struct hci_dev *hdev)
 		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;
@@ -2032,7 +2032,7 @@ static inline void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 	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 7c0e571..2a80a91 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -408,6 +408,8 @@ void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *d
 	else
 		flags = ACL_START;
 
+	bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
+
 	hci_send_acl(conn->hcon, skb, flags);
 }
 
@@ -461,6 +463,8 @@ static inline void l2cap_send_sframe(struct l2cap_chan *chan, u16 control)
 	else
 		flags = ACL_START;
 
+	bt_cb(skb)->force_active = chan->force_active;
+
 	hci_send_acl(chan->conn->hcon, skb, flags);
 }
 
@@ -1089,6 +1093,7 @@ void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
 	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 c98360d..9f99e1d 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -436,6 +436,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
 	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);
@@ -484,6 +485,21 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
 
 		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;
@@ -584,6 +600,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
 	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;
 
@@ -660,6 +677,23 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
 		chan->flushable = opt;
 		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 = 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;
@@ -975,6 +1009,7 @@ void l2cap_sock_init(struct sock *sk, struct sock *parent)
 		chan->role_switch = pchan->role_switch;
 		chan->force_reliable = pchan->force_reliable;
 		chan->flushable = pchan->flushable;
+		chan->force_active = pchan->force_active;
 	} else {
 		chan->imtu = L2CAP_DEFAULT_MTU;
 		chan->omtu = 0;
@@ -991,6 +1026,7 @@ void l2cap_sock_init(struct sock *sk, struct sock *parent)
 		chan->role_switch = 0;
 		chan->force_reliable = 0;
 		chan->flushable = BT_FLUSHABLE_OFF;
+		chan->force_active = BT_POWER_FORCE_ACTIVE_ON;
 	}
 
 	/* Default config options */
-- 
1.7.3.1

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Ville Tervo]

Hi Jaikumar,

On Mon, May 23, 2011 at 06:06:04PM -0700, ext Jaikumar Ganesh wrote:
> 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.
> 

I would prefer keeping old way the default way. Otherwise you need to update
all socket users in user space. Other that that this looks good to me.

-- 
Ville

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Luiz Augusto von Dentz]

Hi Jaikumar,

On Tue, May 24, 2011 at 11:37 AM, Ville Tervo <ville.tervo@nokia.com> wrote:
> Hi Jaikumar,
>
> On Mon, May 23, 2011 at 06:06:04PM -0700, ext Jaikumar Ganesh wrote:
>> 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.
>>
>
> I would prefer keeping old way the default way. Otherwise you need to update
> all socket users in user space. Other that that this looks good to me.

What is wrong that we need such control to be done in userspace?


-- 
Luiz Augusto von Dentz
Computer Engineer

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Jaikumar Ganesh]

Hi Luiz, Ville:

On Tue, May 24, 2011 at 9:20 AM, Luiz Augusto von Dentz
<luiz.dentz@gmail.com> wrote:
>
> Hi Jaikumar,
>
> On Tue, May 24, 2011 at 11:37 AM, Ville Tervo <ville.tervo@nokia.com> wrote:
> > Hi Jaikumar,
> >
> > On Mon, May 23, 2011 at 06:06:04PM -0700, ext Jaikumar Ganesh wrote:
> >> 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.
> >>
> >
> > I would prefer keeping old way the default way. Otherwise you need to update
> > all socket users in user space. Other that that this looks good to me.
>
> What is wrong that we need such control to be done in userspace?

I don't think my emails reached the list so sending it again.

Ville:
    Its the other way round. With this approach and the default value,
only the HID
userspace socket needs to be modified - nothing else.

Luiz:
    The HID devices can send data even when in sniff mode and hence we
need to change the userspace
L2CAP socket option. While sending data without exiting sniff mode for
A2DP for example, causes problems
as explained in the commit message.


>
>
> --
> Luiz Augusto von Dentz
> Computer Engineer

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Luiz Augusto von Dentz]

Hi Jaikumar,

On Tue, May 24, 2011 at 7:44 PM, Jaikumar Ganesh <jaikumar@google.com> wrote:
> Hi Luiz, Ville:
>
> On Tue, May 24, 2011 at 9:20 AM, Luiz Augusto von Dentz
> <luiz.dentz@gmail.com> wrote:
>>
>> Hi Jaikumar,
>>
>> On Tue, May 24, 2011 at 11:37 AM, Ville Tervo <ville.tervo@nokia.com> wrote:
>> > Hi Jaikumar,
>> >
>> > On Mon, May 23, 2011 at 06:06:04PM -0700, ext Jaikumar Ganesh wrote:
>> >> 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.
>> >>
>> >
>> > I would prefer keeping old way the default way. Otherwise you need to update
>> > all socket users in user space. Other that that this looks good to me.
>>
>> What is wrong that we need such control to be done in userspace?
>
> I don't think my emails reached the list so sending it again.
>
> Ville:
>    Its the other way round. With this approach and the default value,
> only the HID
> userspace socket needs to be modified - nothing else.
>
> Luiz:
>    The HID devices can send data even when in sniff mode and hence we
> need to change the userspace
> L2CAP socket option. While sending data without exiting sniff mode for
> A2DP for example, causes problems
> as explained in the commit message.

Now I get it, we should definitely fix it for a2dp/hfp, but still
introducing new socket options it is a quite dangerous game, I wonder
how much power do we really save in case of HID and at what cost since
it probably add latency to input devices while on sniff mode.

-- 
Luiz Augusto von Dentz
Computer Engineer

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Jaikumar Ganesh]

Luiz:

On Tue, May 24, 2011 at 11:24 AM, Luiz Augusto von Dentz
<luiz.dentz@gmail.com> wrote:
> Hi Jaikumar,
>
> On Tue, May 24, 2011 at 7:44 PM, Jaikumar Ganesh <jaikumar@google.com> wrote:
>> Hi Luiz, Ville:
>>
>> On Tue, May 24, 2011 at 9:20 AM, Luiz Augusto von Dentz
>> <luiz.dentz@gmail.com> wrote:
>>>
>>> Hi Jaikumar,
>>>
>>> On Tue, May 24, 2011 at 11:37 AM, Ville Tervo <ville.tervo@nokia.com> wrote:
>>> > Hi Jaikumar,
>>> >
>>> > On Mon, May 23, 2011 at 06:06:04PM -0700, ext Jaikumar Ganesh wrote:
>>> >> 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.
>>> >>
>>> >
>>> > I would prefer keeping old way the default way. Otherwise you need to update
>>> > all socket users in user space. Other that that this looks good to me.
>>>
>>> What is wrong that we need such control to be done in userspace?
>>
>> I don't think my emails reached the list so sending it again.
>>
>> Ville:
>>    Its the other way round. With this approach and the default value,
>> only the HID
>> userspace socket needs to be modified - nothing else.
>>
>> Luiz:
>>    The HID devices can send data even when in sniff mode and hence we
>> need to change the userspace
>> L2CAP socket option. While sending data without exiting sniff mode for
>> A2DP for example, causes problems
>> as explained in the commit message.
>
> Now I get it, we should definitely fix it for a2dp/hfp, but still
> introducing new socket options it is a quite dangerous game, I wonder
> how much power do we really save in case of HID and at what cost since
> it probably add latency to input devices while on sniff mode.

This has been discussed many times on this list and some patches posted before.
But they added socket options to the old style sockets. We need a
socket option for this case. I dug up this old discussion:
http://search.gmane.org/?query=What+is+the+motivation+for+conn-%3Epower_save&group=gmane.linux.bluez.kernel
>
> --
> Luiz Augusto von Dentz
> Computer Engineer
>

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Gustavo F. Padovan]

Hi Jaikumar,

* Jaikumar Ganesh <jaikumar@google.com> [2011-05-23 18:06:04 -0700]:

> 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>
> ---
>  include/net/bluetooth/bluetooth.h |    8 ++++++++
>  include/net/bluetooth/hci_core.h  |    2 +-
>  include/net/bluetooth/l2cap.h     |    1 +
>  net/bluetooth/hci_conn.c          |    9 ++++++---
>  net/bluetooth/hci_core.c          |    4 ++--
>  net/bluetooth/l2cap_core.c        |    5 +++++
>  net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
>  7 files changed, 59 insertions(+), 6 deletions(-)
> 
> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> index 4375043..af930a3 100644
> --- a/include/net/bluetooth/bluetooth.h
> +++ b/include/net/bluetooth/bluetooth.h
> @@ -69,6 +69,13 @@ struct bt_security {
>  #define BT_FLUSHABLE_OFF	0
>  #define BT_FLUSHABLE_ON		1
>  
> +#define BT_POWER	9
> +struct bt_power {
> +	__u8 force_active;
> +};
> +#define BT_POWER_FORCE_ACTIVE_OFF 0
> +#define BT_POWER_FORCE_ACTIVE_ON  1
> +
>  #define BT_INFO(fmt, arg...) printk(KERN_INFO "Bluetooth: " fmt "\n" , ## arg)
>  #define BT_ERR(fmt, arg...)  printk(KERN_ERR "%s: " fmt "\n" , __func__ , ## arg)
>  #define BT_DBG(fmt, arg...)  pr_debug("%s: " fmt "\n" , __func__ , ## arg)
> @@ -150,6 +157,7 @@ struct bt_skb_cb {
>  	__u8 retries;
>  	__u8 sar;
>  	unsigned short channel;
> +	__u8 force_active;
>  };
>  #define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))
>  
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 6c994c0..0747841 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -427,7 +427,7 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
>  int hci_conn_change_link_key(struct hci_conn *conn);
>  int hci_conn_switch_role(struct hci_conn *conn, __u8 role);
>  
> -void hci_conn_enter_active_mode(struct hci_conn *conn);
> +void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active);
>  void hci_conn_enter_sniff_mode(struct hci_conn *conn);
>  
>  void hci_conn_hold_device(struct hci_conn *conn);
> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> index d09c9b1..942970d 100644
> --- a/include/net/bluetooth/l2cap.h
> +++ b/include/net/bluetooth/l2cap.h
> @@ -302,6 +302,7 @@ struct l2cap_chan {
>  	__u8		role_switch;
>  	__u8		force_reliable;
>  	__u8		flushable;
> +	__u8		force_active;
>  
>  	__u8		ident;
>  
> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
> index 3163330..5195715 100644
> --- a/net/bluetooth/hci_conn.c
> +++ b/net/bluetooth/hci_conn.c
> @@ -497,7 +497,7 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8
>  	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 */
> @@ -676,7 +676,7 @@ int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
>  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;
>  
> @@ -685,7 +685,10 @@ void hci_conn_enter_active_mode(struct hci_conn *conn)
>  	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 b6bda3f..be68e7d 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -1893,7 +1893,7 @@ static inline void hci_sched_acl(struct hci_dev *hdev)
>  		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;
> @@ -2032,7 +2032,7 @@ static inline void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
>  	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 7c0e571..2a80a91 100644
> --- a/net/bluetooth/l2cap_core.c
> +++ b/net/bluetooth/l2cap_core.c
> @@ -408,6 +408,8 @@ void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *d
>  	else
>  		flags = ACL_START;
>  
> +	bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
> +
>  	hci_send_acl(conn->hcon, skb, flags);
>  }
>  
> @@ -461,6 +463,8 @@ static inline void l2cap_send_sframe(struct l2cap_chan *chan, u16 control)
>  	else
>  		flags = ACL_START;
>  
> +	bt_cb(skb)->force_active = chan->force_active;
> +
>  	hci_send_acl(chan->conn->hcon, skb, flags);
>  }
>  
> @@ -1089,6 +1093,7 @@ void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
>  	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 c98360d..9f99e1d 100644
> --- a/net/bluetooth/l2cap_sock.c
> +++ b/net/bluetooth/l2cap_sock.c
> @@ -436,6 +436,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
>  	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);
> @@ -484,6 +485,21 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
>  
>  		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;
> @@ -584,6 +600,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
>  	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;
>  
> @@ -660,6 +677,23 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
>  		chan->flushable = opt;
>  		break;
>  
> +	case BT_POWER:
> +		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
> +				&& sk->sk_type != SOCK_RAW) {
> +			err = -EINVAL;

This need to be rebased against bluetooth-next. Not sure, but this seems to be
the only place of conflict.

-- 
Gustavo F. Padovan
http://profusion.mobi

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Jaikumar Ganesh]

[-- Attachment #1: Type: text/plain, Size: 9720 bytes --]

Gustavo,

On Mon, May 30, 2011 at 3:11 PM, Gustavo F. Padovan
<padovan@profusion.mobi> wrote:
> Hi Jaikumar,
>
> * Jaikumar Ganesh <jaikumar@google.com> [2011-05-23 18:06:04 -0700]:
>
>> 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>
>> ---
>>  include/net/bluetooth/bluetooth.h |    8 ++++++++
>>  include/net/bluetooth/hci_core.h  |    2 +-
>>  include/net/bluetooth/l2cap.h     |    1 +
>>  net/bluetooth/hci_conn.c          |    9 ++++++---
>>  net/bluetooth/hci_core.c          |    4 ++--
>>  net/bluetooth/l2cap_core.c        |    5 +++++
>>  net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
>>  7 files changed, 59 insertions(+), 6 deletions(-)
>>
>> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
>> index 4375043..af930a3 100644
>> --- a/include/net/bluetooth/bluetooth.h
>> +++ b/include/net/bluetooth/bluetooth.h
>> @@ -69,6 +69,13 @@ struct bt_security {
>>  #define BT_FLUSHABLE_OFF     0
>>  #define BT_FLUSHABLE_ON              1
>>
>> +#define BT_POWER     9
>> +struct bt_power {
>> +     __u8 force_active;
>> +};
>> +#define BT_POWER_FORCE_ACTIVE_OFF 0
>> +#define BT_POWER_FORCE_ACTIVE_ON  1
>> +
>>  #define BT_INFO(fmt, arg...) printk(KERN_INFO "Bluetooth: " fmt "\n" , ## arg)
>>  #define BT_ERR(fmt, arg...)  printk(KERN_ERR "%s: " fmt "\n" , __func__ , ## arg)
>>  #define BT_DBG(fmt, arg...)  pr_debug("%s: " fmt "\n" , __func__ , ## arg)
>> @@ -150,6 +157,7 @@ struct bt_skb_cb {
>>       __u8 retries;
>>       __u8 sar;
>>       unsigned short channel;
>> +     __u8 force_active;
>>  };
>>  #define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))
>>
>> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
>> index 6c994c0..0747841 100644
>> --- a/include/net/bluetooth/hci_core.h
>> +++ b/include/net/bluetooth/hci_core.h
>> @@ -427,7 +427,7 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
>>  int hci_conn_change_link_key(struct hci_conn *conn);
>>  int hci_conn_switch_role(struct hci_conn *conn, __u8 role);
>>
>> -void hci_conn_enter_active_mode(struct hci_conn *conn);
>> +void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active);
>>  void hci_conn_enter_sniff_mode(struct hci_conn *conn);
>>
>>  void hci_conn_hold_device(struct hci_conn *conn);
>> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
>> index d09c9b1..942970d 100644
>> --- a/include/net/bluetooth/l2cap.h
>> +++ b/include/net/bluetooth/l2cap.h
>> @@ -302,6 +302,7 @@ struct l2cap_chan {
>>       __u8            role_switch;
>>       __u8            force_reliable;
>>       __u8            flushable;
>> +     __u8            force_active;
>>
>>       __u8            ident;
>>
>> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
>> index 3163330..5195715 100644
>> --- a/net/bluetooth/hci_conn.c
>> +++ b/net/bluetooth/hci_conn.c
>> @@ -497,7 +497,7 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8
>>       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 */
>> @@ -676,7 +676,7 @@ int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
>>  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;
>>
>> @@ -685,7 +685,10 @@ void hci_conn_enter_active_mode(struct hci_conn *conn)
>>       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 b6bda3f..be68e7d 100644
>> --- a/net/bluetooth/hci_core.c
>> +++ b/net/bluetooth/hci_core.c
>> @@ -1893,7 +1893,7 @@ static inline void hci_sched_acl(struct hci_dev *hdev)
>>               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;
>> @@ -2032,7 +2032,7 @@ static inline void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
>>       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 7c0e571..2a80a91 100644
>> --- a/net/bluetooth/l2cap_core.c
>> +++ b/net/bluetooth/l2cap_core.c
>> @@ -408,6 +408,8 @@ void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *d
>>       else
>>               flags = ACL_START;
>>
>> +     bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
>> +
>>       hci_send_acl(conn->hcon, skb, flags);
>>  }
>>
>> @@ -461,6 +463,8 @@ static inline void l2cap_send_sframe(struct l2cap_chan *chan, u16 control)
>>       else
>>               flags = ACL_START;
>>
>> +     bt_cb(skb)->force_active = chan->force_active;
>> +
>>       hci_send_acl(chan->conn->hcon, skb, flags);
>>  }
>>
>> @@ -1089,6 +1093,7 @@ void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
>>       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 c98360d..9f99e1d 100644
>> --- a/net/bluetooth/l2cap_sock.c
>> +++ b/net/bluetooth/l2cap_sock.c
>> @@ -436,6 +436,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
>>       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);
>> @@ -484,6 +485,21 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
>>
>>               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;
>> @@ -584,6 +600,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
>>       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;
>>
>> @@ -660,6 +677,23 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
>>               chan->flushable = opt;
>>               break;
>>
>> +     case BT_POWER:
>> +             if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
>> +                             && sk->sk_type != SOCK_RAW) {
>> +                     err = -EINVAL;
>
> This need to be rebased against bluetooth-next. Not sure, but this seems to be
> the only place of conflict.

Rebased patch attached.

Thanks

>
> --
> Gustavo F. Padovan
> http://profusion.mobi
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

[-- Attachment #2: 0001-Bluetooth-Add-BT_POWER-L2CAP-socket-option.patch --]
[-- Type: text/x-patch, Size: 8589 bytes --]

From 74e9a75ef48b633aa82e28ec775bb04b630d51ac Mon Sep 17 00:00:00 2001
From: Jaikumar Ganesh <jaikumar@google.com>
Date: Mon, 23 May 2011 18:06:04 -0700
Subject: [PATCH] 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>
---
 include/net/bluetooth/bluetooth.h |    8 ++++++++
 include/net/bluetooth/hci_core.h  |    2 +-
 include/net/bluetooth/l2cap.h     |    1 +
 net/bluetooth/hci_conn.c          |    9 ++++++---
 net/bluetooth/hci_core.c          |    4 ++--
 net/bluetooth/l2cap_core.c        |    5 +++++
 net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
 7 files changed, 59 insertions(+), 6 deletions(-)

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 4375043..af930a3 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -69,6 +69,13 @@ struct bt_security {
 #define BT_FLUSHABLE_OFF	0
 #define BT_FLUSHABLE_ON		1
 
+#define BT_POWER	9
+struct bt_power {
+	__u8 force_active;
+};
+#define BT_POWER_FORCE_ACTIVE_OFF 0
+#define BT_POWER_FORCE_ACTIVE_ON  1
+
 #define BT_INFO(fmt, arg...) printk(KERN_INFO "Bluetooth: " fmt "\n" , ## arg)
 #define BT_ERR(fmt, arg...)  printk(KERN_ERR "%s: " fmt "\n" , __func__ , ## arg)
 #define BT_DBG(fmt, arg...)  pr_debug("%s: " fmt "\n" , __func__ , ## arg)
@@ -150,6 +157,7 @@ struct bt_skb_cb {
 	__u8 retries;
 	__u8 sar;
 	unsigned short channel;
+	__u8 force_active;
 };
 #define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))
 
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index af4b0ed..96afa4d 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -436,7 +436,7 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
 int hci_conn_change_link_key(struct hci_conn *conn);
 int hci_conn_switch_role(struct hci_conn *conn, __u8 role);
 
-void hci_conn_enter_active_mode(struct hci_conn *conn);
+void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active);
 void hci_conn_enter_sniff_mode(struct hci_conn *conn);
 
 void hci_conn_hold_device(struct hci_conn *conn);
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index a2dcbff..0529d27 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -303,6 +303,7 @@ struct l2cap_chan {
 	__u8		role_switch;
 	__u8		force_reliable;
 	__u8		flushable;
+	__u8		force_active;
 
 	__u8		ident;
 
diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 3163330..5195715 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -497,7 +497,7 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8
 	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 */
@@ -676,7 +676,7 @@ int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
 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;
 
@@ -685,7 +685,10 @@ void hci_conn_enter_active_mode(struct hci_conn *conn)
 	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 @@ static inline void hci_sched_acl(struct hci_dev *hdev)
 		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 @@ static inline void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 	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 e730bb4..f458fc1 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -537,6 +537,8 @@ static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
 	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 @@ static inline void l2cap_send_sframe(struct l2cap_chan *chan, u16 control)
 	else
 		flags = ACL_START;
 
+	bt_cb(skb)->force_active = chan->force_active;
+
 	hci_send_acl(chan->conn->hcon, skb, flags);
 }
 
@@ -1215,6 +1219,7 @@ void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
 	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 13d1076..671f1c4 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -391,6 +391,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
 	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);
@@ -439,6 +440,21 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
 
 		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;
@@ -539,6 +555,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
 	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;
 
@@ -615,6 +632,23 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
 		chan->flushable = opt;
 		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 = 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;
@@ -772,6 +806,7 @@ void l2cap_sock_init(struct sock *sk, struct sock *parent)
 		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) {
@@ -802,6 +837,7 @@ void l2cap_sock_init(struct sock *sk, struct sock *parent)
 		chan->role_switch = 0;
 		chan->force_reliable = 0;
 		chan->flushable = BT_FLUSHABLE_OFF;
+		chan->force_active = BT_POWER_FORCE_ACTIVE_ON;
 	}
 
 	/* Default config options */
-- 
1.7.3.1

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Gustavo F. Padovan]

* Jaikumar Ganesh <jaikumarg@gmail.com> [2011-05-31 18:53:51 -0700]:

> Gustavo,
> 
> On Mon, May 30, 2011 at 3:11 PM, Gustavo F. Padovan
> <padovan@profusion.mobi> wrote:
> > Hi Jaikumar,
> >
> > * Jaikumar Ganesh <jaikumar@google.com> [2011-05-23 18:06:04 -0700]:
> >
> >> 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>
> >> ---
> >>  include/net/bluetooth/bluetooth.h |    8 ++++++++
> >>  include/net/bluetooth/hci_core.h  |    2 +-
> >>  include/net/bluetooth/l2cap.h     |    1 +
> >>  net/bluetooth/hci_conn.c          |    9 ++++++---
> >>  net/bluetooth/hci_core.c          |    4 ++--
> >>  net/bluetooth/l2cap_core.c        |    5 +++++
> >>  net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
> >>  7 files changed, 59 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> >> index 4375043..af930a3 100644
> >> --- a/include/net/bluetooth/bluetooth.h
> >> +++ b/include/net/bluetooth/bluetooth.h
> >> @@ -69,6 +69,13 @@ struct bt_security {
> >>  #define BT_FLUSHABLE_OFF     0
> >>  #define BT_FLUSHABLE_ON              1
> >>
> >> +#define BT_POWER     9
> >> +struct bt_power {
> >> +     __u8 force_active;
> >> +};
> >> +#define BT_POWER_FORCE_ACTIVE_OFF 0
> >> +#define BT_POWER_FORCE_ACTIVE_ON  1
> >> +
> >>  #define BT_INFO(fmt, arg...) printk(KERN_INFO "Bluetooth: " fmt "\n" , ## arg)
> >>  #define BT_ERR(fmt, arg...)  printk(KERN_ERR "%s: " fmt "\n" , __func__ , ## arg)
> >>  #define BT_DBG(fmt, arg...)  pr_debug("%s: " fmt "\n" , __func__ , ## arg)
> >> @@ -150,6 +157,7 @@ struct bt_skb_cb {
> >>       __u8 retries;
> >>       __u8 sar;
> >>       unsigned short channel;
> >> +     __u8 force_active;
> >>  };
> >>  #define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))
> >>
> >> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> >> index 6c994c0..0747841 100644
> >> --- a/include/net/bluetooth/hci_core.h
> >> +++ b/include/net/bluetooth/hci_core.h
> >> @@ -427,7 +427,7 @@ int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
> >>  int hci_conn_change_link_key(struct hci_conn *conn);
> >>  int hci_conn_switch_role(struct hci_conn *conn, __u8 role);
> >>
> >> -void hci_conn_enter_active_mode(struct hci_conn *conn);
> >> +void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active);
> >>  void hci_conn_enter_sniff_mode(struct hci_conn *conn);
> >>
> >>  void hci_conn_hold_device(struct hci_conn *conn);
> >> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> >> index d09c9b1..942970d 100644
> >> --- a/include/net/bluetooth/l2cap.h
> >> +++ b/include/net/bluetooth/l2cap.h
> >> @@ -302,6 +302,7 @@ struct l2cap_chan {
> >>       __u8            role_switch;
> >>       __u8            force_reliable;
> >>       __u8            flushable;
> >> +     __u8            force_active;
> >>
> >>       __u8            ident;
> >>
> >> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
> >> index 3163330..5195715 100644
> >> --- a/net/bluetooth/hci_conn.c
> >> +++ b/net/bluetooth/hci_conn.c
> >> @@ -497,7 +497,7 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8
> >>       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 */
> >> @@ -676,7 +676,7 @@ int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
> >>  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;
> >>
> >> @@ -685,7 +685,10 @@ void hci_conn_enter_active_mode(struct hci_conn *conn)
> >>       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 b6bda3f..be68e7d 100644
> >> --- a/net/bluetooth/hci_core.c
> >> +++ b/net/bluetooth/hci_core.c
> >> @@ -1893,7 +1893,7 @@ static inline void hci_sched_acl(struct hci_dev *hdev)
> >>               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;
> >> @@ -2032,7 +2032,7 @@ static inline void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
> >>       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 7c0e571..2a80a91 100644
> >> --- a/net/bluetooth/l2cap_core.c
> >> +++ b/net/bluetooth/l2cap_core.c
> >> @@ -408,6 +408,8 @@ void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *d
> >>       else
> >>               flags = ACL_START;
> >>
> >> +     bt_cb(skb)->force_active = BT_POWER_FORCE_ACTIVE_ON;
> >> +
> >>       hci_send_acl(conn->hcon, skb, flags);
> >>  }
> >>
> >> @@ -461,6 +463,8 @@ static inline void l2cap_send_sframe(struct l2cap_chan *chan, u16 control)
> >>       else
> >>               flags = ACL_START;
> >>
> >> +     bt_cb(skb)->force_active = chan->force_active;
> >> +
> >>       hci_send_acl(chan->conn->hcon, skb, flags);
> >>  }
> >>
> >> @@ -1089,6 +1093,7 @@ void l2cap_do_send(struct l2cap_chan *chan, struct sk_buff *skb)
> >>       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 c98360d..9f99e1d 100644
> >> --- a/net/bluetooth/l2cap_sock.c
> >> +++ b/net/bluetooth/l2cap_sock.c
> >> @@ -436,6 +436,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
> >>       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);
> >> @@ -484,6 +485,21 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch
> >>
> >>               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;
> >> @@ -584,6 +600,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
> >>       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;
> >>
> >> @@ -660,6 +677,23 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch
> >>               chan->flushable = opt;
> >>               break;
> >>
> >> +     case BT_POWER:
> >> +             if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
> >> +                             && sk->sk_type != SOCK_RAW) {
> >> +                     err = -EINVAL;
> >
> > This need to be rebased against bluetooth-next. Not sure, but this seems to be
> > the only place of conflict.
> 
> Rebased patch attached.
> 
> Thanks
> 
> >
> > --
> > Gustavo F. Padovan
> > http://profusion.mobi
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> >

> From 74e9a75ef48b633aa82e28ec775bb04b630d51ac Mon Sep 17 00:00:00 2001
> From: Jaikumar Ganesh <jaikumar@google.com>
> Date: Mon, 23 May 2011 18:06:04 -0700
> Subject: [PATCH] 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>
> ---
>  include/net/bluetooth/bluetooth.h |    8 ++++++++
>  include/net/bluetooth/hci_core.h  |    2 +-
>  include/net/bluetooth/l2cap.h     |    1 +
>  net/bluetooth/hci_conn.c          |    9 ++++++---
>  net/bluetooth/hci_core.c          |    4 ++--
>  net/bluetooth/l2cap_core.c        |    5 +++++
>  net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
>  7 files changed, 59 insertions(+), 6 deletions(-)

I applied it, but please next time send a inline patch. Thanks.

-- 
Gustavo F. Padovan
http://profusion.mobi

Re: [PATCH] Bluetooth: Add BT_POWER L2CAP socket option.

[Marcel Holtmann]

Hi Gustavo,

> > Based on discussions on linux-bluetooth and patches submitted by
> > Andrei Emeltchenko.
> > 
> > Signed-off-by: Jaikumar Ganesh <jaikumar@google.com>
> > ---
> >  include/net/bluetooth/bluetooth.h |    8 ++++++++
> >  include/net/bluetooth/hci_core.h  |    2 +-
> >  include/net/bluetooth/l2cap.h     |    1 +
> >  net/bluetooth/hci_conn.c          |    9 ++++++---
> >  net/bluetooth/hci_core.c          |    4 ++--
> >  net/bluetooth/l2cap_core.c        |    5 +++++
> >  net/bluetooth/l2cap_sock.c        |   36 ++++++++++++++++++++++++++++++++++++
> >  7 files changed, 59 insertions(+), 6 deletions(-)
> 
> I applied it, but please next time send a inline patch. Thanks.

actually rather see us clean up all the variables with proper flags
first and then redo this patch cleanly.

Regards

Marcel