/*
     Copyright (c) 2010,2011 Code Aurora Forum.  All rights reserved.
     Copyright (c) 2011,2012 Intel Corp.
  
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License version 2 and
     only version 2 as published by the Free Software Foundation.
  
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
  */
  
  #include <net/bluetooth/bluetooth.h>
  #include <net/bluetooth/hci_core.h>
  #include <net/bluetooth/l2cap.h>

  #include "a2mp.h"

  #include "amp.h"

  /* Global AMP Manager list */
  LIST_HEAD(amp_mgr_list);
  DEFINE_MUTEX(amp_mgr_list_lock);

  /* A2MP build & send command helper functions */
  static struct a2mp_cmd *__a2mp_build(u8 code, u8 ident, u16 len, void *data)
  {
  	struct a2mp_cmd *cmd;
  	int plen;
  
  	plen = sizeof(*cmd) + len;
  	cmd = kzalloc(plen, GFP_KERNEL);
  	if (!cmd)
  		return NULL;
  
  	cmd->code = code;
  	cmd->ident = ident;
  	cmd->len = cpu_to_le16(len);
  
  	memcpy(cmd->data, data, len);
  
  	return cmd;
  }

  void a2mp_send(struct amp_mgr *mgr, u8 code, u8 ident, u16 len, void *data)

  {
  	struct l2cap_chan *chan = mgr->a2mp_chan;
  	struct a2mp_cmd *cmd;
  	u16 total_len = len + sizeof(*cmd);
  	struct kvec iv;
  	struct msghdr msg;
  
  	cmd = __a2mp_build(code, ident, len, data);
  	if (!cmd)
  		return;
  
  	iv.iov_base = cmd;
  	iv.iov_len = total_len;
  
  	memset(&msg, 0, sizeof(msg));
  
  	msg.msg_iov = (struct iovec *) &iv;
  	msg.msg_iovlen = 1;

  	l2cap_chan_send(chan, &msg, total_len);

  
  	kfree(cmd);
  }

  u8 __next_ident(struct amp_mgr *mgr)

  {
  	if (++mgr->ident == 0)
  		mgr->ident = 1;
  
  	return mgr->ident;
  }

  /* hci_dev_list shall be locked */

  static void __a2mp_add_cl(struct amp_mgr *mgr, struct a2mp_cl *cl)

  {

  	struct hci_dev *hdev;

  	int i = 1;

  	cl[0].id = AMP_ID_BREDR;
  	cl[0].type = AMP_TYPE_BREDR;
  	cl[0].status = AMP_STATUS_BLUETOOTH_ONLY;

  
  	list_for_each_entry(hdev, &hci_dev_list, list) {

  		if (hdev->dev_type == HCI_AMP) {
  			cl[i].id = hdev->id;
  			cl[i].type = hdev->amp_type;

  			if (test_bit(HCI_UP, &hdev->flags))
  				cl[i].status = hdev->amp_status;
  			else
  				cl[i].status = AMP_STATUS_POWERED_DOWN;

  			i++;
  		}

  	}
  }

  /* Processing A2MP messages */
  static int a2mp_command_rej(struct amp_mgr *mgr, struct sk_buff *skb,
  			    struct a2mp_cmd *hdr)
  {
  	struct a2mp_cmd_rej *rej = (void *) skb->data;
  
  	if (le16_to_cpu(hdr->len) < sizeof(*rej))
  		return -EINVAL;
  
  	BT_DBG("ident %d reason %d", hdr->ident, le16_to_cpu(rej->reason));
  
  	skb_pull(skb, sizeof(*rej));
  
  	return 0;
  }

  static int a2mp_discover_req(struct amp_mgr *mgr, struct sk_buff *skb,
  			     struct a2mp_cmd *hdr)
  {
  	struct a2mp_discov_req *req = (void *) skb->data;
  	u16 len = le16_to_cpu(hdr->len);
  	struct a2mp_discov_rsp *rsp;
  	u16 ext_feat;
  	u8 num_ctrl;

  	struct hci_dev *hdev;

  
  	if (len < sizeof(*req))
  		return -EINVAL;
  
  	skb_pull(skb, sizeof(*req));
  
  	ext_feat = le16_to_cpu(req->ext_feat);
  
  	BT_DBG("mtu %d efm 0x%4.4x", le16_to_cpu(req->mtu), ext_feat);
  
  	/* check that packet is not broken for now */
  	while (ext_feat & A2MP_FEAT_EXT) {
  		if (len < sizeof(ext_feat))
  			return -EINVAL;
  
  		ext_feat = get_unaligned_le16(skb->data);
  		BT_DBG("efm 0x%4.4x", ext_feat);
  		len -= sizeof(ext_feat);
  		skb_pull(skb, sizeof(ext_feat));
  	}
  
  	read_lock(&hci_dev_list_lock);

  	/* at minimum the BR/EDR needs to be listed */
  	num_ctrl = 1;
  
  	list_for_each_entry(hdev, &hci_dev_list, list) {
  		if (hdev->dev_type == HCI_AMP)
  			num_ctrl++;
  	}

  	len = num_ctrl * sizeof(struct a2mp_cl) + sizeof(*rsp);
  	rsp = kmalloc(len, GFP_ATOMIC);
  	if (!rsp) {
  		read_unlock(&hci_dev_list_lock);
  		return -ENOMEM;
  	}

  	rsp->mtu = cpu_to_le16(L2CAP_A2MP_DEFAULT_MTU);

  	rsp->ext_feat = 0;

  	__a2mp_add_cl(mgr, rsp->cl);

  
  	read_unlock(&hci_dev_list_lock);
  
  	a2mp_send(mgr, A2MP_DISCOVER_RSP, hdr->ident, len, rsp);
  
  	kfree(rsp);
  	return 0;
  }

  static int a2mp_discover_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
  			     struct a2mp_cmd *hdr)
  {
  	struct a2mp_discov_rsp *rsp = (void *) skb->data;
  	u16 len = le16_to_cpu(hdr->len);
  	struct a2mp_cl *cl;
  	u16 ext_feat;

  	bool found = false;

  
  	if (len < sizeof(*rsp))
  		return -EINVAL;
  
  	len -= sizeof(*rsp);
  	skb_pull(skb, sizeof(*rsp));
  
  	ext_feat = le16_to_cpu(rsp->ext_feat);
  
  	BT_DBG("mtu %d efm 0x%4.4x", le16_to_cpu(rsp->mtu), ext_feat);
  
  	/* check that packet is not broken for now */
  	while (ext_feat & A2MP_FEAT_EXT) {
  		if (len < sizeof(ext_feat))
  			return -EINVAL;
  
  		ext_feat = get_unaligned_le16(skb->data);
  		BT_DBG("efm 0x%4.4x", ext_feat);
  		len -= sizeof(ext_feat);
  		skb_pull(skb, sizeof(ext_feat));
  	}
  
  	cl = (void *) skb->data;
  	while (len >= sizeof(*cl)) {
  		BT_DBG("Remote AMP id %d type %d status %d", cl->id, cl->type,
  		       cl->status);

  		if (cl->id != AMP_ID_BREDR && cl->type != AMP_TYPE_BREDR) {

  			struct a2mp_info_req req;

  			found = true;

  			req.id = cl->id;
  			a2mp_send(mgr, A2MP_GETINFO_REQ, __next_ident(mgr),
  				  sizeof(req), &req);
  		}
  
  		len -= sizeof(*cl);
  		cl = (void *) skb_pull(skb, sizeof(*cl));
  	}

  	/* Fall back to L2CAP init sequence */
  	if (!found) {
  		struct l2cap_conn *conn = mgr->l2cap_conn;
  		struct l2cap_chan *chan;
  
  		mutex_lock(&conn->chan_lock);
  
  		list_for_each_entry(chan, &conn->chan_l, list) {
  
  			BT_DBG("chan %p state %s", chan,
  			       state_to_string(chan->state));

  			if (chan->scid == L2CAP_CID_A2MP)

  				continue;
  
  			l2cap_chan_lock(chan);
  
  			if (chan->state == BT_CONNECT)
  				l2cap_send_conn_req(chan);
  
  			l2cap_chan_unlock(chan);
  		}
  
  		mutex_unlock(&conn->chan_lock);
  	}

  	return 0;
  }

  static int a2mp_change_notify(struct amp_mgr *mgr, struct sk_buff *skb,
  			      struct a2mp_cmd *hdr)
  {
  	struct a2mp_cl *cl = (void *) skb->data;
  
  	while (skb->len >= sizeof(*cl)) {
  		BT_DBG("Controller id %d type %d status %d", cl->id, cl->type,
  		       cl->status);
  		cl = (struct a2mp_cl *) skb_pull(skb, sizeof(*cl));
  	}
  
  	/* TODO send A2MP_CHANGE_RSP */
  
  	return 0;
  }

  static int a2mp_getinfo_req(struct amp_mgr *mgr, struct sk_buff *skb,
  			    struct a2mp_cmd *hdr)
  {
  	struct a2mp_info_req *req  = (void *) skb->data;

  	struct hci_dev *hdev;
  
  	if (le16_to_cpu(hdr->len) < sizeof(*req))
  		return -EINVAL;
  
  	BT_DBG("id %d", req->id);

  	hdev = hci_dev_get(req->id);

  	if (!hdev || hdev->dev_type != HCI_AMP) {

  		struct a2mp_info_rsp rsp;
  
  		rsp.id = req->id;
  		rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
  
  		a2mp_send(mgr, A2MP_GETINFO_RSP, hdr->ident, sizeof(rsp),
  			  &rsp);

  		goto done;

  	}

  	set_bit(READ_LOC_AMP_INFO, &mgr->state);

  	hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_INFO, 0, NULL);
  
  done:
  	if (hdev)
  		hci_dev_put(hdev);

  
  	skb_pull(skb, sizeof(*req));
  	return 0;
  }

  static int a2mp_getinfo_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
  			    struct a2mp_cmd *hdr)
  {
  	struct a2mp_info_rsp *rsp = (struct a2mp_info_rsp *) skb->data;
  	struct a2mp_amp_assoc_req req;
  	struct amp_ctrl *ctrl;
  
  	if (le16_to_cpu(hdr->len) < sizeof(*rsp))
  		return -EINVAL;
  
  	BT_DBG("id %d status 0x%2.2x", rsp->id, rsp->status);
  
  	if (rsp->status)
  		return -EINVAL;

  	ctrl = amp_ctrl_add(mgr, rsp->id);

  	if (!ctrl)
  		return -ENOMEM;

  	req.id = rsp->id;
  	a2mp_send(mgr, A2MP_GETAMPASSOC_REQ, __next_ident(mgr), sizeof(req),
  		  &req);
  
  	skb_pull(skb, sizeof(*rsp));
  	return 0;
  }

  static int a2mp_getampassoc_req(struct amp_mgr *mgr, struct sk_buff *skb,
  				struct a2mp_cmd *hdr)
  {
  	struct a2mp_amp_assoc_req *req = (void *) skb->data;
  	struct hci_dev *hdev;

  	struct amp_mgr *tmp;

  
  	if (le16_to_cpu(hdr->len) < sizeof(*req))
  		return -EINVAL;
  
  	BT_DBG("id %d", req->id);

  	/* Make sure that other request is not processed */
  	tmp = amp_mgr_lookup_by_state(READ_LOC_AMP_ASSOC);

  	hdev = hci_dev_get(req->id);

  	if (!hdev || hdev->amp_type == AMP_TYPE_BREDR || tmp) {

  		struct a2mp_amp_assoc_rsp rsp;
  		rsp.id = req->id;

  
  		if (tmp) {
  			rsp.status = A2MP_STATUS_COLLISION_OCCURED;
  			amp_mgr_put(tmp);
  		} else {
  			rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
  		}

  
  		a2mp_send(mgr, A2MP_GETAMPASSOC_RSP, hdr->ident, sizeof(rsp),
  			  &rsp);

  
  		goto done;

  	}

  	amp_read_loc_assoc(hdev, mgr);

  done:

  	if (hdev)
  		hci_dev_put(hdev);
  
  	skb_pull(skb, sizeof(*req));
  	return 0;
  }

  static int a2mp_getampassoc_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
  				struct a2mp_cmd *hdr)
  {
  	struct a2mp_amp_assoc_rsp *rsp = (void *) skb->data;
  	u16 len = le16_to_cpu(hdr->len);
  	struct hci_dev *hdev;
  	struct amp_ctrl *ctrl;
  	struct hci_conn *hcon;

  	size_t assoc_len;

  
  	if (len < sizeof(*rsp))
  		return -EINVAL;

  	assoc_len = len - sizeof(*rsp);
  
  	BT_DBG("id %d status 0x%2.2x assoc len %zu", rsp->id, rsp->status,
  	       assoc_len);

  
  	if (rsp->status)
  		return -EINVAL;
  
  	/* Save remote ASSOC data */
  	ctrl = amp_ctrl_lookup(mgr, rsp->id);
  	if (ctrl) {

  		u8 *assoc;

  		assoc = kmemdup(rsp->amp_assoc, assoc_len, GFP_KERNEL);

  		if (!assoc) {
  			amp_ctrl_put(ctrl);
  			return -ENOMEM;
  		}

  		ctrl->assoc = assoc;
  		ctrl->assoc_len = assoc_len;
  		ctrl->assoc_rem_len = assoc_len;
  		ctrl->assoc_len_so_far = 0;
  
  		amp_ctrl_put(ctrl);
  	}
  
  	/* Create Phys Link */
  	hdev = hci_dev_get(rsp->id);
  	if (!hdev)
  		return -EINVAL;

  	hcon = phylink_add(hdev, mgr, rsp->id, true);

  	if (!hcon)
  		goto done;
  
  	BT_DBG("Created hcon %p: loc:%d -> rem:%d", hcon, hdev->id, rsp->id);

  	mgr->bredr_chan->remote_amp_id = rsp->id;

  	amp_create_phylink(hdev, mgr, hcon);

  done:
  	hci_dev_put(hdev);
  	skb_pull(skb, len);
  	return 0;
  }

  static int a2mp_createphyslink_req(struct amp_mgr *mgr, struct sk_buff *skb,
  				   struct a2mp_cmd *hdr)
  {
  	struct a2mp_physlink_req *req = (void *) skb->data;
  
  	struct a2mp_physlink_rsp rsp;
  	struct hci_dev *hdev;

  	struct hci_conn *hcon;

  	struct amp_ctrl *ctrl;

  
  	if (le16_to_cpu(hdr->len) < sizeof(*req))
  		return -EINVAL;
  
  	BT_DBG("local_id %d, remote_id %d", req->local_id, req->remote_id);
  
  	rsp.local_id = req->remote_id;
  	rsp.remote_id = req->local_id;
  
  	hdev = hci_dev_get(req->remote_id);

  	if (!hdev || hdev->amp_type == AMP_TYPE_BREDR) {

  		rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
  		goto send_rsp;
  	}

  	ctrl = amp_ctrl_lookup(mgr, rsp.remote_id);
  	if (!ctrl) {

  		ctrl = amp_ctrl_add(mgr, rsp.remote_id);

  		if (ctrl) {
  			amp_ctrl_get(ctrl);
  		} else {
  			rsp.status = A2MP_STATUS_UNABLE_START_LINK_CREATION;
  			goto send_rsp;
  		}
  	}
  
  	if (ctrl) {

  		size_t assoc_len = le16_to_cpu(hdr->len) - sizeof(*req);
  		u8 *assoc;

  		assoc = kmemdup(req->amp_assoc, assoc_len, GFP_KERNEL);

  		if (!assoc) {
  			amp_ctrl_put(ctrl);
  			return -ENOMEM;
  		}

  		ctrl->assoc = assoc;
  		ctrl->assoc_len = assoc_len;
  		ctrl->assoc_rem_len = assoc_len;
  		ctrl->assoc_len_so_far = 0;
  
  		amp_ctrl_put(ctrl);
  	}

  	hcon = phylink_add(hdev, mgr, req->local_id, false);

  	if (hcon) {

  		amp_accept_phylink(hdev, mgr, hcon);

  		rsp.status = A2MP_STATUS_SUCCESS;
  	} else {
  		rsp.status = A2MP_STATUS_UNABLE_START_LINK_CREATION;
  	}

  
  send_rsp:
  	if (hdev)
  		hci_dev_put(hdev);

  	/* Reply error now and success after HCI Write Remote AMP Assoc
  	   command complete with success status
  	 */
  	if (rsp.status != A2MP_STATUS_SUCCESS) {
  		a2mp_send(mgr, A2MP_CREATEPHYSLINK_RSP, hdr->ident,
  			  sizeof(rsp), &rsp);
  	} else {

  		set_bit(WRITE_REMOTE_AMP_ASSOC, &mgr->state);

  		mgr->ident = hdr->ident;
  	}

  
  	skb_pull(skb, le16_to_cpu(hdr->len));
  	return 0;
  }

  static int a2mp_discphyslink_req(struct amp_mgr *mgr, struct sk_buff *skb,
  				 struct a2mp_cmd *hdr)
  {
  	struct a2mp_physlink_req *req = (void *) skb->data;
  	struct a2mp_physlink_rsp rsp;
  	struct hci_dev *hdev;

  	struct hci_conn *hcon;

  
  	if (le16_to_cpu(hdr->len) < sizeof(*req))
  		return -EINVAL;
  
  	BT_DBG("local_id %d remote_id %d", req->local_id, req->remote_id);
  
  	rsp.local_id = req->remote_id;
  	rsp.remote_id = req->local_id;
  	rsp.status = A2MP_STATUS_SUCCESS;

  	hdev = hci_dev_get(req->remote_id);

  	if (!hdev) {
  		rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
  		goto send_rsp;
  	}

  	hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
  				       &mgr->l2cap_conn->hcon->dst);

  	if (!hcon) {
  		BT_ERR("No phys link exist");
  		rsp.status = A2MP_STATUS_NO_PHYSICAL_LINK_EXISTS;
  		goto clean;
  	}

  	/* TODO Disconnect Phys Link here */

  clean:

  	hci_dev_put(hdev);
  
  send_rsp:
  	a2mp_send(mgr, A2MP_DISCONNPHYSLINK_RSP, hdr->ident, sizeof(rsp), &rsp);
  
  	skb_pull(skb, sizeof(*req));
  	return 0;
  }

  static inline int a2mp_cmd_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
  			       struct a2mp_cmd *hdr)
  {

  	BT_DBG("ident %d code 0x%2.2x", hdr->ident, hdr->code);

  
  	skb_pull(skb, le16_to_cpu(hdr->len));
  	return 0;
  }

  /* Handle A2MP signalling */
  static int a2mp_chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
  {

  	struct a2mp_cmd *hdr;

  	struct amp_mgr *mgr = chan->data;
  	int err = 0;
  
  	amp_mgr_get(mgr);
  
  	while (skb->len >= sizeof(*hdr)) {

  		u16 len;
  
  		hdr = (void *) skb->data;
  		len = le16_to_cpu(hdr->len);

  		BT_DBG("code 0x%2.2x id %d len %u", hdr->code, hdr->ident, len);

  
  		skb_pull(skb, sizeof(*hdr));
  
  		if (len > skb->len || !hdr->ident) {
  			err = -EINVAL;
  			break;
  		}
  
  		mgr->ident = hdr->ident;
  
  		switch (hdr->code) {
  		case A2MP_COMMAND_REJ:

  			a2mp_command_rej(mgr, skb, hdr);
  			break;

  		case A2MP_DISCOVER_REQ:

  			err = a2mp_discover_req(mgr, skb, hdr);
  			break;

  		case A2MP_CHANGE_NOTIFY:

  			err = a2mp_change_notify(mgr, skb, hdr);
  			break;

  		case A2MP_GETINFO_REQ:

  			err = a2mp_getinfo_req(mgr, skb, hdr);
  			break;

  		case A2MP_GETAMPASSOC_REQ:

  			err = a2mp_getampassoc_req(mgr, skb, hdr);
  			break;

  		case A2MP_CREATEPHYSLINK_REQ:

  			err = a2mp_createphyslink_req(mgr, skb, hdr);
  			break;

  		case A2MP_DISCONNPHYSLINK_REQ:

  			err = a2mp_discphyslink_req(mgr, skb, hdr);
  			break;

  		case A2MP_DISCOVER_RSP:

  			err = a2mp_discover_rsp(mgr, skb, hdr);
  			break;

  		case A2MP_GETINFO_RSP:

  			err = a2mp_getinfo_rsp(mgr, skb, hdr);
  			break;

  		case A2MP_GETAMPASSOC_RSP:

  			err = a2mp_getampassoc_rsp(mgr, skb, hdr);
  			break;
  
  		case A2MP_CHANGE_RSP:

  		case A2MP_CREATEPHYSLINK_RSP:
  		case A2MP_DISCONNPHYSLINK_RSP:

  			err = a2mp_cmd_rsp(mgr, skb, hdr);
  			break;

  		default:
  			BT_ERR("Unknown A2MP sig cmd 0x%2.2x", hdr->code);
  			err = -EINVAL;
  			break;
  		}
  	}
  
  	if (err) {
  		struct a2mp_cmd_rej rej;

  		rej.reason = cpu_to_le16(0);

  		hdr = (void *) skb->data;

  
  		BT_DBG("Send A2MP Rej: cmd 0x%2.2x err %d", hdr->code, err);
  
  		a2mp_send(mgr, A2MP_COMMAND_REJ, hdr->ident, sizeof(rej),
  			  &rej);
  	}
  
  	/* Always free skb and return success error code to prevent
  	   from sending L2CAP Disconnect over A2MP channel */
  	kfree_skb(skb);
  
  	amp_mgr_put(mgr);
  
  	return 0;
  }

  static void a2mp_chan_close_cb(struct l2cap_chan *chan)
  {

  	l2cap_chan_put(chan);

  }

  static void a2mp_chan_state_change_cb(struct l2cap_chan *chan, int state,
  				      int err)

  {
  	struct amp_mgr *mgr = chan->data;
  
  	if (!mgr)
  		return;
  
  	BT_DBG("chan %p state %s", chan, state_to_string(state));
  
  	chan->state = state;
  
  	switch (state) {
  	case BT_CLOSED:
  		if (mgr)
  			amp_mgr_put(mgr);
  		break;
  	}
  }
  
  static struct sk_buff *a2mp_chan_alloc_skb_cb(struct l2cap_chan *chan,

  					      unsigned long hdr_len,

  					      unsigned long len, int nb)
  {

  	struct sk_buff *skb;

  	skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);

  	if (!skb)
  		return ERR_PTR(-ENOMEM);
  
  	return skb;

  }

  static const struct l2cap_ops a2mp_chan_ops = {

  	.name = "L2CAP A2MP channel",

  	.recv = a2mp_chan_recv_cb,

  	.close = a2mp_chan_close_cb,
  	.state_change = a2mp_chan_state_change_cb,
  	.alloc_skb = a2mp_chan_alloc_skb_cb,
  
  	/* Not implemented for A2MP */

  	.new_connection = l2cap_chan_no_new_connection,
  	.teardown = l2cap_chan_no_teardown,
  	.ready = l2cap_chan_no_ready,

  	.defer = l2cap_chan_no_defer,

  	.resume = l2cap_chan_no_resume,

  	.set_shutdown = l2cap_chan_no_set_shutdown,

  	.get_sndtimeo = l2cap_chan_no_get_sndtimeo,

  	.memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec,

  };

  static struct l2cap_chan *a2mp_chan_open(struct l2cap_conn *conn, bool locked)

  {
  	struct l2cap_chan *chan;
  	int err;
  
  	chan = l2cap_chan_create();
  	if (!chan)
  		return NULL;
  
  	BT_DBG("chan %p", chan);

  	chan->chan_type = L2CAP_CHAN_FIXED;
  	chan->scid = L2CAP_CID_A2MP;
  	chan->dcid = L2CAP_CID_A2MP;
  	chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
  	chan->imtu = L2CAP_A2MP_DEFAULT_MTU;

  	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
  
  	chan->ops = &a2mp_chan_ops;
  
  	l2cap_chan_set_defaults(chan);
  	chan->remote_max_tx = chan->max_tx;
  	chan->remote_tx_win = chan->tx_win;
  
  	chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
  	chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
  
  	skb_queue_head_init(&chan->tx_q);
  
  	chan->mode = L2CAP_MODE_ERTM;
  
  	err = l2cap_ertm_init(chan);
  	if (err < 0) {
  		l2cap_chan_del(chan, 0);
  		return NULL;
  	}
  
  	chan->conf_state = 0;

  	if (locked)
  		__l2cap_chan_add(conn, chan);
  	else
  		l2cap_chan_add(conn, chan);

  
  	chan->remote_mps = chan->omtu;
  	chan->mps = chan->omtu;
  
  	chan->state = BT_CONNECTED;
  
  	return chan;
  }

  
  /* AMP Manager functions */

  struct amp_mgr *amp_mgr_get(struct amp_mgr *mgr)

  {

  	BT_DBG("mgr %p orig refcnt %d", mgr, atomic_read(&mgr->kref.refcount));

  
  	kref_get(&mgr->kref);

  
  	return mgr;

  }
  
  static void amp_mgr_destroy(struct kref *kref)
  {
  	struct amp_mgr *mgr = container_of(kref, struct amp_mgr, kref);
  
  	BT_DBG("mgr %p", mgr);

  	mutex_lock(&amp_mgr_list_lock);
  	list_del(&mgr->list);
  	mutex_unlock(&amp_mgr_list_lock);

  	amp_ctrl_list_flush(mgr);

  	kfree(mgr);
  }
  
  int amp_mgr_put(struct amp_mgr *mgr)
  {

  	BT_DBG("mgr %p orig refcnt %d", mgr, atomic_read(&mgr->kref.refcount));

  
  	return kref_put(&mgr->kref, &amp_mgr_destroy);
  }

  static struct amp_mgr *amp_mgr_create(struct l2cap_conn *conn, bool locked)

  {
  	struct amp_mgr *mgr;
  	struct l2cap_chan *chan;
  
  	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
  	if (!mgr)
  		return NULL;
  
  	BT_DBG("conn %p mgr %p", conn, mgr);
  
  	mgr->l2cap_conn = conn;

  	chan = a2mp_chan_open(conn, locked);

  	if (!chan) {
  		kfree(mgr);
  		return NULL;
  	}
  
  	mgr->a2mp_chan = chan;
  	chan->data = mgr;
  
  	conn->hcon->amp_mgr = mgr;
  
  	kref_init(&mgr->kref);

  	/* Remote AMP ctrl list initialization */
  	INIT_LIST_HEAD(&mgr->amp_ctrls);
  	mutex_init(&mgr->amp_ctrls_lock);

  	mutex_lock(&amp_mgr_list_lock);
  	list_add(&mgr->list, &amp_mgr_list);
  	mutex_unlock(&amp_mgr_list_lock);

  	return mgr;
  }

  
  struct l2cap_chan *a2mp_channel_create(struct l2cap_conn *conn,
  				       struct sk_buff *skb)
  {
  	struct amp_mgr *mgr;

  	if (conn->hcon->type != ACL_LINK)
  		return NULL;

  	mgr = amp_mgr_create(conn, false);

  	if (!mgr) {
  		BT_ERR("Could not create AMP manager");
  		return NULL;
  	}
  
  	BT_DBG("mgr: %p chan %p", mgr, mgr->a2mp_chan);
  
  	return mgr->a2mp_chan;
  }

  
  struct amp_mgr *amp_mgr_lookup_by_state(u8 state)
  {
  	struct amp_mgr *mgr;
  
  	mutex_lock(&amp_mgr_list_lock);
  	list_for_each_entry(mgr, &amp_mgr_list, list) {

  		if (test_and_clear_bit(state, &mgr->state)) {

  			amp_mgr_get(mgr);
  			mutex_unlock(&amp_mgr_list_lock);
  			return mgr;
  		}
  	}
  	mutex_unlock(&amp_mgr_list_lock);
  
  	return NULL;
  }

  
  void a2mp_send_getinfo_rsp(struct hci_dev *hdev)
  {
  	struct amp_mgr *mgr;
  	struct a2mp_info_rsp rsp;
  
  	mgr = amp_mgr_lookup_by_state(READ_LOC_AMP_INFO);
  	if (!mgr)
  		return;
  
  	BT_DBG("%s mgr %p", hdev->name, mgr);
  
  	rsp.id = hdev->id;
  	rsp.status = A2MP_STATUS_INVALID_CTRL_ID;

  	if (hdev->amp_type != AMP_TYPE_BREDR) {

  		rsp.status = 0;
  		rsp.total_bw = cpu_to_le32(hdev->amp_total_bw);
  		rsp.max_bw = cpu_to_le32(hdev->amp_max_bw);
  		rsp.min_latency = cpu_to_le32(hdev->amp_min_latency);
  		rsp.pal_cap = cpu_to_le16(hdev->amp_pal_cap);
  		rsp.assoc_size = cpu_to_le16(hdev->amp_assoc_size);
  	}
  
  	a2mp_send(mgr, A2MP_GETINFO_RSP, mgr->ident, sizeof(rsp), &rsp);
  	amp_mgr_put(mgr);
  }

  
  void a2mp_send_getampassoc_rsp(struct hci_dev *hdev, u8 status)
  {
  	struct amp_mgr *mgr;
  	struct amp_assoc *loc_assoc = &hdev->loc_assoc;
  	struct a2mp_amp_assoc_rsp *rsp;
  	size_t len;
  
  	mgr = amp_mgr_lookup_by_state(READ_LOC_AMP_ASSOC);
  	if (!mgr)
  		return;
  
  	BT_DBG("%s mgr %p", hdev->name, mgr);
  
  	len = sizeof(struct a2mp_amp_assoc_rsp) + loc_assoc->len;
  	rsp = kzalloc(len, GFP_KERNEL);
  	if (!rsp) {
  		amp_mgr_put(mgr);
  		return;
  	}
  
  	rsp->id = hdev->id;
  
  	if (status) {
  		rsp->status = A2MP_STATUS_INVALID_CTRL_ID;
  	} else {
  		rsp->status = A2MP_STATUS_SUCCESS;
  		memcpy(rsp->amp_assoc, loc_assoc->data, loc_assoc->len);
  	}
  
  	a2mp_send(mgr, A2MP_GETAMPASSOC_RSP, mgr->ident, len, rsp);
  	amp_mgr_put(mgr);
  	kfree(rsp);
  }

  void a2mp_send_create_phy_link_req(struct hci_dev *hdev, u8 status)
  {
  	struct amp_mgr *mgr;
  	struct amp_assoc *loc_assoc = &hdev->loc_assoc;
  	struct a2mp_physlink_req *req;
  	struct l2cap_chan *bredr_chan;
  	size_t len;
  
  	mgr = amp_mgr_lookup_by_state(READ_LOC_AMP_ASSOC_FINAL);
  	if (!mgr)
  		return;
  
  	len = sizeof(*req) + loc_assoc->len;
  
  	BT_DBG("%s mgr %p assoc_len %zu", hdev->name, mgr, len);
  
  	req = kzalloc(len, GFP_KERNEL);
  	if (!req) {
  		amp_mgr_put(mgr);
  		return;
  	}
  
  	bredr_chan = mgr->bredr_chan;
  	if (!bredr_chan)
  		goto clean;
  
  	req->local_id = hdev->id;

  	req->remote_id = bredr_chan->remote_amp_id;

  	memcpy(req->amp_assoc, loc_assoc->data, loc_assoc->len);
  
  	a2mp_send(mgr, A2MP_CREATEPHYSLINK_REQ, __next_ident(mgr), len, req);
  
  clean:
  	amp_mgr_put(mgr);
  	kfree(req);
  }

  void a2mp_send_create_phy_link_rsp(struct hci_dev *hdev, u8 status)
  {
  	struct amp_mgr *mgr;
  	struct a2mp_physlink_rsp rsp;
  	struct hci_conn *hs_hcon;
  
  	mgr = amp_mgr_lookup_by_state(WRITE_REMOTE_AMP_ASSOC);
  	if (!mgr)
  		return;
  
  	hs_hcon = hci_conn_hash_lookup_state(hdev, AMP_LINK, BT_CONNECT);
  	if (!hs_hcon) {
  		rsp.status = A2MP_STATUS_UNABLE_START_LINK_CREATION;
  	} else {
  		rsp.remote_id = hs_hcon->remote_id;
  		rsp.status = A2MP_STATUS_SUCCESS;
  	}
  
  	BT_DBG("%s mgr %p hs_hcon %p status %u", hdev->name, mgr, hs_hcon,
  	       status);
  
  	rsp.local_id = hdev->id;
  	a2mp_send(mgr, A2MP_CREATEPHYSLINK_RSP, mgr->ident, sizeof(rsp), &rsp);
  	amp_mgr_put(mgr);
  }

  void a2mp_discover_amp(struct l2cap_chan *chan)
  {
  	struct l2cap_conn *conn = chan->conn;
  	struct amp_mgr *mgr = conn->hcon->amp_mgr;
  	struct a2mp_discov_req req;
  
  	BT_DBG("chan %p conn %p mgr %p", chan, conn, mgr);
  
  	if (!mgr) {
  		mgr = amp_mgr_create(conn, true);
  		if (!mgr)
  			return;
  	}
  
  	mgr->bredr_chan = chan;
  
  	req.mtu = cpu_to_le16(L2CAP_A2MP_DEFAULT_MTU);
  	req.ext_feat = 0;
  	a2mp_send(mgr, A2MP_DISCOVER_REQ, 1, sizeof(req), &req);
  }