net/caif/cfctrl.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright (C) ST-Ericsson AB 2010
  * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
  * License terms: GNU General Public License (GPL) version 2
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__

 #include <linux/stddef.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
 #include <linux/pkt_sched.h>
 #include <net/caif/caif_layer.h>
 #include <net/caif/cfpkt.h>
 #include <net/caif/cfctrl.h>

 #define container_obj(layr) container_of(layr, struct cfctrl, serv.layer)
 #define UTILITY_NAME_LENGTH 16
 #define CFPKT_CTRL_PKT_LEN 20

 #ifdef CAIF_NO_LOOP
 static int handle_loop(struct cfctrl *ctrl,
 			      int cmd, struct cfpkt *pkt){
 	return -1;
 }
 #else
 static int handle_loop(struct cfctrl *ctrl,
 		int cmd, struct cfpkt *pkt);
 #endif
 static int cfctrl_recv(struct cflayer *layr, struct cfpkt *pkt);
 static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
 			   int phyid);


 struct cflayer *cfctrl_create(void)
 {
 	struct dev_info dev_info;
 	struct cfctrl *this =
 		kzalloc(sizeof(struct cfctrl), GFP_ATOMIC);
 	if (!this)
 		return NULL;
 	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
 	memset(&dev_info, 0, sizeof(dev_info));
 	dev_info.id = 0xff;
 	cfsrvl_init(&this->serv, 0, &dev_info, false);
 	atomic_set(&this->req_seq_no, 1);
 	atomic_set(&this->rsp_seq_no, 1);
 	this->serv.layer.receive = cfctrl_recv;
 	sprintf(this->serv.layer.name, "ctrl");
 	this->serv.layer.ctrlcmd = cfctrl_ctrlcmd;
 #ifndef CAIF_NO_LOOP
 	spin_lock_init(&this->loop_linkid_lock);
 	this->loop_linkid = 1;
 #endif
 	spin_lock_init(&this->info_list_lock);
 	INIT_LIST_HEAD(&this->list);
 	return &this->serv.layer;
 }

 void cfctrl_remove(struct cflayer *layer)
 {
 	struct cfctrl_request_info *p, *tmp;
 	struct cfctrl *ctrl = container_obj(layer);

 	spin_lock_bh(&ctrl->info_list_lock);
 	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
 		list_del(&p->list);
 		kfree(p);
 	}
 	spin_unlock_bh(&ctrl->info_list_lock);
 	kfree(layer);
 }

 static bool param_eq(const struct cfctrl_link_param *p1,
 			const struct cfctrl_link_param *p2)
 {
 	bool eq =
 	    p1->linktype == p2->linktype &&
 	    p1->priority == p2->priority &&
 	    p1->phyid == p2->phyid &&
 	    p1->endpoint == p2->endpoint && p1->chtype == p2->chtype;

 	if (!eq)
 		return false;

 	switch (p1->linktype) {
 	case CFCTRL_SRV_VEI:
 		return true;
 	case CFCTRL_SRV_DATAGRAM:
 		return p1->u.datagram.connid == p2->u.datagram.connid;
 	case CFCTRL_SRV_RFM:
 		return
 		    p1->u.rfm.connid == p2->u.rfm.connid &&
 		    strcmp(p1->u.rfm.volume, p2->u.rfm.volume) == 0;
 	case CFCTRL_SRV_UTIL:
 		return
 		    p1->u.utility.fifosize_kb == p2->u.utility.fifosize_kb
 		    && p1->u.utility.fifosize_bufs ==
 		    p2->u.utility.fifosize_bufs
 		    && strcmp(p1->u.utility.name, p2->u.utility.name) == 0
 		    && p1->u.utility.paramlen == p2->u.utility.paramlen
 		    && memcmp(p1->u.utility.params, p2->u.utility.params,
 			      p1->u.utility.paramlen) == 0;

 	case CFCTRL_SRV_VIDEO:
 		return p1->u.video.connid == p2->u.video.connid;
 	case CFCTRL_SRV_DBG:
 		return true;
 	case CFCTRL_SRV_DECM:
 		return false;
 	default:
 		return false;
 	}
 	return false;
 }

 static bool cfctrl_req_eq(const struct cfctrl_request_info *r1,
 			  const struct cfctrl_request_info *r2)
 {
 	if (r1->cmd != r2->cmd)
 		return false;
 	if (r1->cmd == CFCTRL_CMD_LINK_SETUP)
 		return param_eq(&r1->param, &r2->param);
 	else
 		return r1->channel_id == r2->channel_id;
 }

 /* Insert request at the end */
 static void cfctrl_insert_req(struct cfctrl *ctrl,
 			      struct cfctrl_request_info *req)
 {
 	spin_lock_bh(&ctrl->info_list_lock);
 	atomic_inc(&ctrl->req_seq_no);
 	req->sequence_no = atomic_read(&ctrl->req_seq_no);
 	list_add_tail(&req->list, &ctrl->list);
 	spin_unlock_bh(&ctrl->info_list_lock);
 }

 /* Compare and remove request */
 static struct cfctrl_request_info *cfctrl_remove_req(struct cfctrl *ctrl,
 						struct cfctrl_request_info *req)
 {
 	struct cfctrl_request_info *p, *tmp, *first;

 	first = list_first_entry(&ctrl->list, struct cfctrl_request_info, list);

 	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
 		if (cfctrl_req_eq(req, p)) {
 			if (p != first)
 				pr_warn("Requests are not received in order\n");

 			atomic_set(&ctrl->rsp_seq_no,
 					 p->sequence_no);
 			list_del(&p->list);
 			goto out;
 		}
 	}
 	p = NULL;
 out:
 	return p;
 }

 struct cfctrl_rsp *cfctrl_get_respfuncs(struct cflayer *layer)
 {
 	struct cfctrl *this = container_obj(layer);
 	return &this->res;
 }

 static void init_info(struct caif_payload_info *info, struct cfctrl *cfctrl)
 {
 	info->hdr_len = 0;
 	info->channel_id = cfctrl->serv.layer.id;
 	info->dev_info = &cfctrl->serv.dev_info;
 }

 void cfctrl_enum_req(struct cflayer *layer, u8 physlinkid)
 {
 	struct cfctrl *cfctrl = container_obj(layer);
 	struct cfpkt *pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
 	struct cflayer *dn = cfctrl->serv.layer.dn;
 	if (!pkt)
 		return;
 	if (!dn) {
 		pr_debug("not able to send enum request\n");
 		return;
 	}
 	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
 	init_info(cfpkt_info(pkt), cfctrl);
 	cfpkt_info(pkt)->dev_info->id = physlinkid;
 	cfctrl->serv.dev_info.id = physlinkid;
 	cfpkt_addbdy(pkt, CFCTRL_CMD_ENUM);
 	cfpkt_addbdy(pkt, physlinkid);
 	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
 	dn->transmit(dn, pkt);
 }

 int cfctrl_linkup_request(struct cflayer *layer,
 			   struct cfctrl_link_param *param,
 			   struct cflayer *user_layer)
 {
 	struct cfctrl *cfctrl = container_obj(layer);
 	u32 tmp32;
 	u16 tmp16;
 	u8 tmp8;
 	struct cfctrl_request_info *req;
 	int ret;
 	char utility_name[16];
 	struct cfpkt *pkt;
 	struct cflayer *dn = cfctrl->serv.layer.dn;

 	if (!dn) {
 		pr_debug("not able to send linkup request\n");
 		return -ENODEV;
 	}

 	if (cfctrl_cancel_req(layer, user_layer) > 0) {
 		/* Slight Paranoia, check if already connecting */
 		pr_err("Duplicate connect request for same client\n");
 		WARN_ON(1);
 		return -EALREADY;
 	}

 	pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
 	if (!pkt)
 		return -ENOMEM;
 	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_SETUP);
 	cfpkt_addbdy(pkt, (param->chtype << 4) | param->linktype);
 	cfpkt_addbdy(pkt, (param->priority << 3) | param->phyid);
 	cfpkt_addbdy(pkt, param->endpoint & 0x03);

 	switch (param->linktype) {
 	case CFCTRL_SRV_VEI:
 		break;
 	case CFCTRL_SRV_VIDEO:
 		cfpkt_addbdy(pkt, (u8) param->u.video.connid);
 		break;
 	case CFCTRL_SRV_DBG:
 		break;
 	case CFCTRL_SRV_DATAGRAM:
 		tmp32 = cpu_to_le32(param->u.datagram.connid);
 		cfpkt_add_body(pkt, &tmp32, 4);
 		break;
 	case CFCTRL_SRV_RFM:
 		/* Construct a frame, convert DatagramConnectionID to network
 		 * format long and copy it out...
 		 */
 		tmp32 = cpu_to_le32(param->u.rfm.connid);
 		cfpkt_add_body(pkt, &tmp32, 4);
 		/* Add volume name, including zero termination... */
 		cfpkt_add_body(pkt, param->u.rfm.volume,
 			       strlen(param->u.rfm.volume) + 1);
 		break;
 	case CFCTRL_SRV_UTIL:
 		tmp16 = cpu_to_le16(param->u.utility.fifosize_kb);
 		cfpkt_add_body(pkt, &tmp16, 2);
 		tmp16 = cpu_to_le16(param->u.utility.fifosize_bufs);
 		cfpkt_add_body(pkt, &tmp16, 2);
 		memset(utility_name, 0, sizeof(utility_name));
 		strncpy(utility_name, param->u.utility.name,
 			UTILITY_NAME_LENGTH - 1);
 		cfpkt_add_body(pkt, utility_name, UTILITY_NAME_LENGTH);
 		tmp8 = param->u.utility.paramlen;
 		cfpkt_add_body(pkt, &tmp8, 1);
 		cfpkt_add_body(pkt, param->u.utility.params,
 			       param->u.utility.paramlen);
 		break;
 	default:
 		pr_warn("Request setup of bad link type = %d\n",
 			param->linktype);
 		return -EINVAL;
 	}
 	req = kzalloc(sizeof(*req), GFP_KERNEL);
 	if (!req)
 		return -ENOMEM;
 	req->client_layer = user_layer;
 	req->cmd = CFCTRL_CMD_LINK_SETUP;
 	req->param = *param;
 	cfctrl_insert_req(cfctrl, req);
 	init_info(cfpkt_info(pkt), cfctrl);
 	/*
 	 * NOTE:Always send linkup and linkdown request on the same
 	 *	device as the payload. Otherwise old queued up payload
 	 *	might arrive with the newly allocated channel ID.
 	 */
 	cfpkt_info(pkt)->dev_info->id = param->phyid;
 	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
 	ret =
 	    dn->transmit(dn, pkt);
 	if (ret < 0) {
 		int count;

 		count = cfctrl_cancel_req(&cfctrl->serv.layer,
 						user_layer);
 		if (count != 1)
 			pr_err("Could not remove request (%d)", count);
 			return -ENODEV;
 	}
 	return 0;
 }

 int cfctrl_linkdown_req(struct cflayer *layer, u8 channelid,
 				struct cflayer *client)
 {
 	int ret;
 	struct cfctrl *cfctrl = container_obj(layer);
 	struct cfpkt *pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
 	struct cflayer *dn = cfctrl->serv.layer.dn;

 	if (!pkt)
 		return -ENOMEM;

 	if (!dn) {
 		pr_debug("not able to send link-down request\n");
 		return -ENODEV;
 	}

 	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_DESTROY);
 	cfpkt_addbdy(pkt, channelid);
 	init_info(cfpkt_info(pkt), cfctrl);
 	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
 	ret =
 	    dn->transmit(dn, pkt);
 #ifndef CAIF_NO_LOOP
 	cfctrl->loop_linkused[channelid] = 0;
 #endif
 	return ret;
 }

 int cfctrl_cancel_req(struct cflayer *layr, struct cflayer *adap_layer)
 {
 	struct cfctrl_request_info *p, *tmp;
 	struct cfctrl *ctrl = container_obj(layr);
 	int found = 0;
 	spin_lock_bh(&ctrl->info_list_lock);

 	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
 		if (p->client_layer == adap_layer) {
 			list_del(&p->list);
 			kfree(p);
 			found++;
 		}
 	}

 	spin_unlock_bh(&ctrl->info_list_lock);
 	return found;
 }

 static int cfctrl_recv(struct cflayer *layer, struct cfpkt *pkt)
 {
 	u8 cmdrsp;
 	u8 cmd;
 	int ret = -1;
 	u16 tmp16;
 	u8 len;
 	u8 param[255];
 	u8 linkid;
 	struct cfctrl *cfctrl = container_obj(layer);
 	struct cfctrl_request_info rsp, *req;


 	cfpkt_extr_head(pkt, &cmdrsp, 1);
 	cmd = cmdrsp & CFCTRL_CMD_MASK;
 	if (cmd != CFCTRL_CMD_LINK_ERR
 	    && CFCTRL_RSP_BIT != (CFCTRL_RSP_BIT & cmdrsp)
 		&& CFCTRL_ERR_BIT != (CFCTRL_ERR_BIT & cmdrsp)) {
 		if (handle_loop(cfctrl, cmd, pkt) != 0)
 			cmdrsp |= CFCTRL_ERR_BIT;
 	}

 	switch (cmd) {
 	case CFCTRL_CMD_LINK_SETUP:
 		{
 			enum cfctrl_srv serv;
 			enum cfctrl_srv servtype;
 			u8 endpoint;
 			u8 physlinkid;
 			u8 prio;
 			u8 tmp;
 			u32 tmp32;
 			u8 *cp;
 			int i;
 			struct cfctrl_link_param linkparam;
 			memset(&linkparam, 0, sizeof(linkparam));

 			cfpkt_extr_head(pkt, &tmp, 1);

 			serv = tmp & CFCTRL_SRV_MASK;
 			linkparam.linktype = serv;

 			servtype = tmp >> 4;
 			linkparam.chtype = servtype;

 			cfpkt_extr_head(pkt, &tmp, 1);
 			physlinkid = tmp & 0x07;
 			prio = tmp >> 3;

 			linkparam.priority = prio;
 			linkparam.phyid = physlinkid;
 			cfpkt_extr_head(pkt, &endpoint, 1);
 			linkparam.endpoint = endpoint & 0x03;

 			switch (serv) {
 			case CFCTRL_SRV_VEI:
 			case CFCTRL_SRV_DBG:
 				if (CFCTRL_ERR_BIT & cmdrsp)
 					break;
 				/* Link ID */
 				cfpkt_extr_head(pkt, &linkid, 1);
 				break;
 			case CFCTRL_SRV_VIDEO:
 				cfpkt_extr_head(pkt, &tmp, 1);
 				linkparam.u.video.connid = tmp;
 				if (CFCTRL_ERR_BIT & cmdrsp)
 					break;
 				/* Link ID */
 				cfpkt_extr_head(pkt, &linkid, 1);
 				break;

 			case CFCTRL_SRV_DATAGRAM:
 				cfpkt_extr_head(pkt, &tmp32, 4);
 				linkparam.u.datagram.connid =
 				    le32_to_cpu(tmp32);
 				if (CFCTRL_ERR_BIT & cmdrsp)
 					break;
 				/* Link ID */
 				cfpkt_extr_head(pkt, &linkid, 1);
 				break;
 			case CFCTRL_SRV_RFM:
 				/* Construct a frame, convert
 				 * DatagramConnectionID
 				 * to network format long and copy it out...
 				 */
 				cfpkt_extr_head(pkt, &tmp32, 4);
 				linkparam.u.rfm.connid =
 				  le32_to_cpu(tmp32);
 				cp = (u8 *) linkparam.u.rfm.volume;
 				for (cfpkt_extr_head(pkt, &tmp, 1);
 				     cfpkt_more(pkt) && tmp != '\0';
 				     cfpkt_extr_head(pkt, &tmp, 1))
 					*cp++ = tmp;
 				*cp = '\0';

 				if (CFCTRL_ERR_BIT & cmdrsp)
 					break;
 				/* Link ID */
 				cfpkt_extr_head(pkt, &linkid, 1);

 				break;
 			case CFCTRL_SRV_UTIL:
 				/* Construct a frame, convert
 				 * DatagramConnectionID
 				 * to network format long and copy it out...
 				 */
 				/* Fifosize KB */
 				cfpkt_extr_head(pkt, &tmp16, 2);
 				linkparam.u.utility.fifosize_kb =
 				    le16_to_cpu(tmp16);
 				/* Fifosize bufs */
 				cfpkt_extr_head(pkt, &tmp16, 2);
 				linkparam.u.utility.fifosize_bufs =
 				    le16_to_cpu(tmp16);
 				/* name */
 				cp = (u8 *) linkparam.u.utility.name;
 				caif_assert(sizeof(linkparam.u.utility.name)
 					     >= UTILITY_NAME_LENGTH);
 				for (i = 0;
 				     i < UTILITY_NAME_LENGTH
 				     && cfpkt_more(pkt); i++) {
 					cfpkt_extr_head(pkt, &tmp, 1);
 					*cp++ = tmp;
 				}
 				/* Length */
 				cfpkt_extr_head(pkt, &len, 1);
 				linkparam.u.utility.paramlen = len;
 				/* Param Data */
 				cp = linkparam.u.utility.params;
 				while (cfpkt_more(pkt) && len--) {
 					cfpkt_extr_head(pkt, &tmp, 1);
 					*cp++ = tmp;
 				}
 				if (CFCTRL_ERR_BIT & cmdrsp)
 					break;
 				/* Link ID */
 				cfpkt_extr_head(pkt, &linkid, 1);
 				/* Length */
 				cfpkt_extr_head(pkt, &len, 1);
 				/* Param Data */
 				cfpkt_extr_head(pkt, &param, len);
 				break;
 			default:
 				pr_warn("Request setup, invalid type (%d)\n",
 					serv);
 				goto error;
 			}

 			rsp.cmd = cmd;
 			rsp.param = linkparam;
 			spin_lock_bh(&cfctrl->info_list_lock);
 			req = cfctrl_remove_req(cfctrl, &rsp);

 			if (CFCTRL_ERR_BIT == (CFCTRL_ERR_BIT & cmdrsp) ||
 				cfpkt_erroneous(pkt)) {
 				pr_err("Invalid O/E bit or parse error "
 						"on CAIF control channel\n");
 				cfctrl->res.reject_rsp(cfctrl->serv.layer.up,
 						       0,
 						       req ? req->client_layer
 						       : NULL);
 			} else {
 				cfctrl->res.linksetup_rsp(cfctrl->serv.
 							  layer.up, linkid,
 							  serv, physlinkid,
 							  req ? req->
 							  client_layer : NULL);
 			}

 			if (req != NULL)
 				kfree(req);

 			spin_unlock_bh(&cfctrl->info_list_lock);
 		}
 		break;
 	case CFCTRL_CMD_LINK_DESTROY:
 		cfpkt_extr_head(pkt, &linkid, 1);
 		cfctrl->res.linkdestroy_rsp(cfctrl->serv.layer.up, linkid);
 		break;
 	case CFCTRL_CMD_LINK_ERR:
 		pr_err("Frame Error Indication received\n");
 		cfctrl->res.linkerror_ind();
 		break;
 	case CFCTRL_CMD_ENUM:
 		cfctrl->res.enum_rsp();
 		break;
 	case CFCTRL_CMD_SLEEP:
 		cfctrl->res.sleep_rsp();
 		break;
 	case CFCTRL_CMD_WAKE:
 		cfctrl->res.wake_rsp();
 		break;
 	case CFCTRL_CMD_LINK_RECONF:
 		cfctrl->res.restart_rsp();
 		break;
 	case CFCTRL_CMD_RADIO_SET:
 		cfctrl->res.radioset_rsp();
 		break;
 	default:
 		pr_err("Unrecognized Control Frame\n");
 		goto error;
 		break;
 	}
 	ret = 0;
 error:
 	cfpkt_destroy(pkt);
 	return ret;
 }

 static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
 			int phyid)
 {
 	struct cfctrl *this = container_obj(layr);
 	switch (ctrl) {
 	case _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND:
 	case CAIF_CTRLCMD_FLOW_OFF_IND:
 		spin_lock_bh(&this->info_list_lock);
 		if (!list_empty(&this->list))
 			pr_debug("Received flow off in control layer\n");
 		spin_unlock_bh(&this->info_list_lock);
 		break;
 	case _CAIF_CTRLCMD_PHYIF_DOWN_IND: {
 		struct cfctrl_request_info *p, *tmp;

 		/* Find all connect request and report failure */
 		spin_lock_bh(&this->info_list_lock);
 		list_for_each_entry_safe(p, tmp, &this->list, list) {
 			if (p->param.phyid == phyid) {
 				list_del(&p->list);
 				p->client_layer->ctrlcmd(p->client_layer,
 						CAIF_CTRLCMD_INIT_FAIL_RSP,
 						phyid);
 				kfree(p);
 			}
 		}
 		spin_unlock_bh(&this->info_list_lock);
 		break;
 	}
 	default:
 		break;
 	}
 }

 #ifndef CAIF_NO_LOOP
 static int handle_loop(struct cfctrl *ctrl, int cmd, struct cfpkt *pkt)
 {
 	static int last_linkid;
 	static int dec;
 	u8 linkid, linktype, tmp;
 	switch (cmd) {
 	case CFCTRL_CMD_LINK_SETUP:
 		spin_lock_bh(&ctrl->loop_linkid_lock);
 		if (!dec) {
 			for (linkid = last_linkid + 1; linkid < 254; linkid++)
 				if (!ctrl->loop_linkused[linkid])
 					goto found;
 		}
 		dec = 1;
 		for (linkid = last_linkid - 1; linkid > 1; linkid--)
 			if (!ctrl->loop_linkused[linkid])
 				goto found;
 		spin_unlock_bh(&ctrl->loop_linkid_lock);
 		return -1;
 found:
 		if (linkid < 10)
 			dec = 0;

 		if (!ctrl->loop_linkused[linkid])
 			ctrl->loop_linkused[linkid] = 1;

 		last_linkid = linkid;

 		cfpkt_add_trail(pkt, &linkid, 1);
 		spin_unlock_bh(&ctrl->loop_linkid_lock);
 		cfpkt_peek_head(pkt, &linktype, 1);
 		if (linktype ==  CFCTRL_SRV_UTIL) {
 			tmp = 0x01;
 			cfpkt_add_trail(pkt, &tmp, 1);
 			cfpkt_add_trail(pkt, &tmp, 1);
 		}
 		break;

 	case CFCTRL_CMD_LINK_DESTROY:
 		spin_lock_bh(&ctrl->loop_linkid_lock);
 		cfpkt_peek_head(pkt, &linkid, 1);
 		ctrl->loop_linkused[linkid] = 0;
 		spin_unlock_bh(&ctrl->loop_linkid_lock);
 		break;
 	default:
 		break;
 	}
 	return 0;
 }
 #endif
	/*
	* Copyright (C) ST-Ericsson AB 2010
	* Author: Sjur Brendeland/sjur.brandeland@stericsson.com
	* License terms: GNU General Public License (GPL) version 2
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__

	#include <linux/stddef.h>
	#include <linux/spinlock.h>
	#include <linux/slab.h>
	#include <linux/pkt_sched.h>
	#include <net/caif/caif_layer.h>
	#include <net/caif/cfpkt.h>
	#include <net/caif/cfctrl.h>

	#define container_obj(layr) container_of(layr, struct cfctrl, serv.layer)
	#define UTILITY_NAME_LENGTH 16
	#define CFPKT_CTRL_PKT_LEN 20

	#ifdef CAIF_NO_LOOP
	static int handle_loop(struct cfctrl *ctrl,
	int cmd, struct cfpkt *pkt){
	return -1;
	}
	#else
	static int handle_loop(struct cfctrl *ctrl,
	int cmd, struct cfpkt *pkt);
	#endif
	static int cfctrl_recv(struct cflayer layr, struct cfpkt pkt);
	static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
	int phyid);


	struct cflayer *cfctrl_create(void)
	{
	struct dev_info dev_info;
	struct cfctrl *this =
	kzalloc(sizeof(struct cfctrl), GFP_ATOMIC);
	if (!this)
	return NULL;
	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
	memset(&dev_info, 0, sizeof(dev_info));
	dev_info.id = 0xff;
	cfsrvl_init(&this->serv, 0, &dev_info, false);
	atomic_set(&this->req_seq_no, 1);
	atomic_set(&this->rsp_seq_no, 1);
	this->serv.layer.receive = cfctrl_recv;
	sprintf(this->serv.layer.name, "ctrl");
	this->serv.layer.ctrlcmd = cfctrl_ctrlcmd;
	#ifndef CAIF_NO_LOOP
	spin_lock_init(&this->loop_linkid_lock);
	this->loop_linkid = 1;
	#endif
	spin_lock_init(&this->info_list_lock);
	INIT_LIST_HEAD(&this->list);
	return &this->serv.layer;
	}

	void cfctrl_remove(struct cflayer *layer)
	{
	struct cfctrl_request_info p, tmp;
	struct cfctrl *ctrl = container_obj(layer);

	spin_lock_bh(&ctrl->info_list_lock);
	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
	list_del(&p->list);
	kfree(p);
	}
	spin_unlock_bh(&ctrl->info_list_lock);
	kfree(layer);
	}

	static bool param_eq(const struct cfctrl_link_param *p1,
	const struct cfctrl_link_param *p2)
	{
	bool eq =
	p1->linktype == p2->linktype &&
	p1->priority == p2->priority &&
	p1->phyid == p2->phyid &&
	p1->endpoint == p2->endpoint && p1->chtype == p2->chtype;

	if (!eq)
	return false;

	switch (p1->linktype) {
	case CFCTRL_SRV_VEI:
	return true;
	case CFCTRL_SRV_DATAGRAM:
	return p1->u.datagram.connid == p2->u.datagram.connid;
	case CFCTRL_SRV_RFM:
	return
	p1->u.rfm.connid == p2->u.rfm.connid &&
	strcmp(p1->u.rfm.volume, p2->u.rfm.volume) == 0;
	case CFCTRL_SRV_UTIL:
	return
	p1->u.utility.fifosize_kb == p2->u.utility.fifosize_kb
	&& p1->u.utility.fifosize_bufs ==
	p2->u.utility.fifosize_bufs
	&& strcmp(p1->u.utility.name, p2->u.utility.name) == 0
	&& p1->u.utility.paramlen == p2->u.utility.paramlen
	&& memcmp(p1->u.utility.params, p2->u.utility.params,
	p1->u.utility.paramlen) == 0;

	case CFCTRL_SRV_VIDEO:
	return p1->u.video.connid == p2->u.video.connid;
	case CFCTRL_SRV_DBG:
	return true;
	case CFCTRL_SRV_DECM:
	return false;
	default:
	return false;
	}
	return false;
	}

	static bool cfctrl_req_eq(const struct cfctrl_request_info *r1,
	const struct cfctrl_request_info *r2)
	{
	if (r1->cmd != r2->cmd)
	return false;
	if (r1->cmd == CFCTRL_CMD_LINK_SETUP)
	return param_eq(&r1->param, &r2->param);
	else
	return r1->channel_id == r2->channel_id;
	}

	/* Insert request at the end */
	static void cfctrl_insert_req(struct cfctrl *ctrl,
	struct cfctrl_request_info *req)
	{
	spin_lock_bh(&ctrl->info_list_lock);
	atomic_inc(&ctrl->req_seq_no);
	req->sequence_no = atomic_read(&ctrl->req_seq_no);
	list_add_tail(&req->list, &ctrl->list);
	spin_unlock_bh(&ctrl->info_list_lock);
	}

	/* Compare and remove request */
	static struct cfctrl_request_info cfctrl_remove_req(struct cfctrl ctrl,
	struct cfctrl_request_info *req)
	{
	struct cfctrl_request_info p, tmp, *first;

	first = list_first_entry(&ctrl->list, struct cfctrl_request_info, list);

	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
	if (cfctrl_req_eq(req, p)) {
	if (p != first)
	pr_warn("Requests are not received in order\n");

	atomic_set(&ctrl->rsp_seq_no,
	p->sequence_no);
	list_del(&p->list);
	goto out;
	}
	}
	p = NULL;
	out:
	return p;
	}

	struct cfctrl_rsp cfctrl_get_respfuncs(struct cflayer layer)
	{
	struct cfctrl *this = container_obj(layer);
	return &this->res;
	}

	static void init_info(struct caif_payload_info info, struct cfctrl cfctrl)
	{
	info->hdr_len = 0;
	info->channel_id = cfctrl->serv.layer.id;
	info->dev_info = &cfctrl->serv.dev_info;
	}

	void cfctrl_enum_req(struct cflayer *layer, u8 physlinkid)
	{
	struct cfctrl *cfctrl = container_obj(layer);
	struct cfpkt *pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
	struct cflayer *dn = cfctrl->serv.layer.dn;
	if (!pkt)
	return;
	if (!dn) {
	pr_debug("not able to send enum request\n");
	return;
	}
	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
	init_info(cfpkt_info(pkt), cfctrl);
	cfpkt_info(pkt)->dev_info->id = physlinkid;
	cfctrl->serv.dev_info.id = physlinkid;
	cfpkt_addbdy(pkt, CFCTRL_CMD_ENUM);
	cfpkt_addbdy(pkt, physlinkid);
	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
	dn->transmit(dn, pkt);
	}

	int cfctrl_linkup_request(struct cflayer *layer,
	struct cfctrl_link_param *param,
	struct cflayer *user_layer)
	{
	struct cfctrl *cfctrl = container_obj(layer);
	u32 tmp32;
	u16 tmp16;
	u8 tmp8;
	struct cfctrl_request_info *req;
	int ret;
	char utility_name[16];
	struct cfpkt *pkt;
	struct cflayer *dn = cfctrl->serv.layer.dn;

	if (!dn) {
	pr_debug("not able to send linkup request\n");
	return -ENODEV;
	}

	if (cfctrl_cancel_req(layer, user_layer) > 0) {
	/* Slight Paranoia, check if already connecting */
	pr_err("Duplicate connect request for same client\n");
	WARN_ON(1);
	return -EALREADY;
	}

	pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
	if (!pkt)
	return -ENOMEM;
	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_SETUP);
	cfpkt_addbdy(pkt, (param->chtype << 4) \| param->linktype);
	cfpkt_addbdy(pkt, (param->priority << 3) \| param->phyid);
	cfpkt_addbdy(pkt, param->endpoint & 0x03);

	switch (param->linktype) {
	case CFCTRL_SRV_VEI:
	break;
	case CFCTRL_SRV_VIDEO:
	cfpkt_addbdy(pkt, (u8) param->u.video.connid);
	break;
	case CFCTRL_SRV_DBG:
	break;
	case CFCTRL_SRV_DATAGRAM:
	tmp32 = cpu_to_le32(param->u.datagram.connid);
	cfpkt_add_body(pkt, &tmp32, 4);
	break;
	case CFCTRL_SRV_RFM:
	/* Construct a frame, convert DatagramConnectionID to network
	* format long and copy it out...
	*/
	tmp32 = cpu_to_le32(param->u.rfm.connid);
	cfpkt_add_body(pkt, &tmp32, 4);
	/* Add volume name, including zero termination... */
	cfpkt_add_body(pkt, param->u.rfm.volume,
	strlen(param->u.rfm.volume) + 1);
	break;
	case CFCTRL_SRV_UTIL:
	tmp16 = cpu_to_le16(param->u.utility.fifosize_kb);
	cfpkt_add_body(pkt, &tmp16, 2);
	tmp16 = cpu_to_le16(param->u.utility.fifosize_bufs);
	cfpkt_add_body(pkt, &tmp16, 2);
	memset(utility_name, 0, sizeof(utility_name));
	strncpy(utility_name, param->u.utility.name,
	UTILITY_NAME_LENGTH - 1);
	cfpkt_add_body(pkt, utility_name, UTILITY_NAME_LENGTH);
	tmp8 = param->u.utility.paramlen;
	cfpkt_add_body(pkt, &tmp8, 1);
	cfpkt_add_body(pkt, param->u.utility.params,
	param->u.utility.paramlen);
	break;
	default:
	pr_warn("Request setup of bad link type = %d\n",
	param->linktype);
	return -EINVAL;
	}
	req = kzalloc(sizeof(*req), GFP_KERNEL);
	if (!req)
	return -ENOMEM;
	req->client_layer = user_layer;
	req->cmd = CFCTRL_CMD_LINK_SETUP;
	req->param = *param;
	cfctrl_insert_req(cfctrl, req);
	init_info(cfpkt_info(pkt), cfctrl);
	/*
	* NOTE:Always send linkup and linkdown request on the same
	* device as the payload. Otherwise old queued up payload
	* might arrive with the newly allocated channel ID.
	*/
	cfpkt_info(pkt)->dev_info->id = param->phyid;
	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
	ret =
	dn->transmit(dn, pkt);
	if (ret < 0) {
	int count;

	count = cfctrl_cancel_req(&cfctrl->serv.layer,
	user_layer);
	if (count != 1)
	pr_err("Could not remove request (%d)", count);
	return -ENODEV;
	}
	return 0;
	}

	int cfctrl_linkdown_req(struct cflayer *layer, u8 channelid,
	struct cflayer *client)
	{
	int ret;
	struct cfctrl *cfctrl = container_obj(layer);
	struct cfpkt *pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
	struct cflayer *dn = cfctrl->serv.layer.dn;

	if (!pkt)
	return -ENOMEM;

	if (!dn) {
	pr_debug("not able to send link-down request\n");
	return -ENODEV;
	}

	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_DESTROY);
	cfpkt_addbdy(pkt, channelid);
	init_info(cfpkt_info(pkt), cfctrl);
	cfpkt_set_prio(pkt, TC_PRIO_CONTROL);
	ret =
	dn->transmit(dn, pkt);
	#ifndef CAIF_NO_LOOP
	cfctrl->loop_linkused[channelid] = 0;
	#endif
	return ret;
	}

	int cfctrl_cancel_req(struct cflayer layr, struct cflayer adap_layer)
	{
	struct cfctrl_request_info p, tmp;
	struct cfctrl *ctrl = container_obj(layr);
	int found = 0;
	spin_lock_bh(&ctrl->info_list_lock);

	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
	if (p->client_layer == adap_layer) {
	list_del(&p->list);
	kfree(p);
	found++;
	}
	}

	spin_unlock_bh(&ctrl->info_list_lock);
	return found;
	}

	static int cfctrl_recv(struct cflayer layer, struct cfpkt pkt)
	{
	u8 cmdrsp;
	u8 cmd;
	int ret = -1;
	u16 tmp16;
	u8 len;
	u8 param[255];
	u8 linkid;
	struct cfctrl *cfctrl = container_obj(layer);
	struct cfctrl_request_info rsp, *req;


	cfpkt_extr_head(pkt, &cmdrsp, 1);
	cmd = cmdrsp & CFCTRL_CMD_MASK;
	if (cmd != CFCTRL_CMD_LINK_ERR
	&& CFCTRL_RSP_BIT != (CFCTRL_RSP_BIT & cmdrsp)
	&& CFCTRL_ERR_BIT != (CFCTRL_ERR_BIT & cmdrsp)) {
	if (handle_loop(cfctrl, cmd, pkt) != 0)
	cmdrsp \|= CFCTRL_ERR_BIT;
	}

	switch (cmd) {
	case CFCTRL_CMD_LINK_SETUP:
	{
	enum cfctrl_srv serv;
	enum cfctrl_srv servtype;
	u8 endpoint;
	u8 physlinkid;
	u8 prio;
	u8 tmp;
	u32 tmp32;
	u8 *cp;
	int i;
	struct cfctrl_link_param linkparam;
	memset(&linkparam, 0, sizeof(linkparam));

	cfpkt_extr_head(pkt, &tmp, 1);

	serv = tmp & CFCTRL_SRV_MASK;
	linkparam.linktype = serv;

	servtype = tmp >> 4;
	linkparam.chtype = servtype;

	cfpkt_extr_head(pkt, &tmp, 1);
	physlinkid = tmp & 0x07;
	prio = tmp >> 3;

	linkparam.priority = prio;
	linkparam.phyid = physlinkid;
	cfpkt_extr_head(pkt, &endpoint, 1);
	linkparam.endpoint = endpoint & 0x03;

	switch (serv) {
	case CFCTRL_SRV_VEI:
	case CFCTRL_SRV_DBG:
	if (CFCTRL_ERR_BIT & cmdrsp)
	break;
	/* Link ID */
	cfpkt_extr_head(pkt, &linkid, 1);
	break;
	case CFCTRL_SRV_VIDEO:
	cfpkt_extr_head(pkt, &tmp, 1);
	linkparam.u.video.connid = tmp;
	if (CFCTRL_ERR_BIT & cmdrsp)
	break;
	/* Link ID */
	cfpkt_extr_head(pkt, &linkid, 1);
	break;

	case CFCTRL_SRV_DATAGRAM:
	cfpkt_extr_head(pkt, &tmp32, 4);
	linkparam.u.datagram.connid =
	le32_to_cpu(tmp32);
	if (CFCTRL_ERR_BIT & cmdrsp)
	break;
	/* Link ID */
	cfpkt_extr_head(pkt, &linkid, 1);
	break;
	case CFCTRL_SRV_RFM:
	/* Construct a frame, convert
	* DatagramConnectionID
	* to network format long and copy it out...
	*/
	cfpkt_extr_head(pkt, &tmp32, 4);
	linkparam.u.rfm.connid =
	le32_to_cpu(tmp32);
	cp = (u8 *) linkparam.u.rfm.volume;
	for (cfpkt_extr_head(pkt, &tmp, 1);
	cfpkt_more(pkt) && tmp != '\0';
	cfpkt_extr_head(pkt, &tmp, 1))
	*cp++ = tmp;
	*cp = '\0';

	if (CFCTRL_ERR_BIT & cmdrsp)
	break;
	/* Link ID */
	cfpkt_extr_head(pkt, &linkid, 1);

	break;
	case CFCTRL_SRV_UTIL:
	/* Construct a frame, convert
	* DatagramConnectionID
	* to network format long and copy it out...
	*/
	/* Fifosize KB */
	cfpkt_extr_head(pkt, &tmp16, 2);
	linkparam.u.utility.fifosize_kb =
	le16_to_cpu(tmp16);
	/* Fifosize bufs */
	cfpkt_extr_head(pkt, &tmp16, 2);
	linkparam.u.utility.fifosize_bufs =
	le16_to_cpu(tmp16);
	/* name */
	cp = (u8 *) linkparam.u.utility.name;
	caif_assert(sizeof(linkparam.u.utility.name)
	>= UTILITY_NAME_LENGTH);
	for (i = 0;
	i < UTILITY_NAME_LENGTH
	&& cfpkt_more(pkt); i++) {
	cfpkt_extr_head(pkt, &tmp, 1);
	*cp++ = tmp;
	}
	/* Length */
	cfpkt_extr_head(pkt, &len, 1);
	linkparam.u.utility.paramlen = len;
	/* Param Data */
	cp = linkparam.u.utility.params;
	while (cfpkt_more(pkt) && len--) {
	cfpkt_extr_head(pkt, &tmp, 1);
	*cp++ = tmp;
	}
	if (CFCTRL_ERR_BIT & cmdrsp)
	break;
	/* Link ID */
	cfpkt_extr_head(pkt, &linkid, 1);
	/* Length */
	cfpkt_extr_head(pkt, &len, 1);
	/* Param Data */
	cfpkt_extr_head(pkt, &param, len);
	break;
	default:
	pr_warn("Request setup, invalid type (%d)\n",
	serv);
	goto error;
	}

	rsp.cmd = cmd;
	rsp.param = linkparam;
	spin_lock_bh(&cfctrl->info_list_lock);
	req = cfctrl_remove_req(cfctrl, &rsp);

	if (CFCTRL_ERR_BIT == (CFCTRL_ERR_BIT & cmdrsp) \|\|
	cfpkt_erroneous(pkt)) {
	pr_err("Invalid O/E bit or parse error "
	"on CAIF control channel\n");
	cfctrl->res.reject_rsp(cfctrl->serv.layer.up,
	0,
	req ? req->client_layer
	: NULL);
	} else {
	cfctrl->res.linksetup_rsp(cfctrl->serv.
	layer.up, linkid,
	serv, physlinkid,
	req ? req->
	client_layer : NULL);
	}

	if (req != NULL)
	kfree(req);

	spin_unlock_bh(&cfctrl->info_list_lock);
	}
	break;
	case CFCTRL_CMD_LINK_DESTROY:
	cfpkt_extr_head(pkt, &linkid, 1);
	cfctrl->res.linkdestroy_rsp(cfctrl->serv.layer.up, linkid);
	break;
	case CFCTRL_CMD_LINK_ERR:
	pr_err("Frame Error Indication received\n");
	cfctrl->res.linkerror_ind();
	break;
	case CFCTRL_CMD_ENUM:
	cfctrl->res.enum_rsp();
	break;
	case CFCTRL_CMD_SLEEP:
	cfctrl->res.sleep_rsp();
	break;
	case CFCTRL_CMD_WAKE:
	cfctrl->res.wake_rsp();
	break;
	case CFCTRL_CMD_LINK_RECONF:
	cfctrl->res.restart_rsp();
	break;
	case CFCTRL_CMD_RADIO_SET:
	cfctrl->res.radioset_rsp();
	break;
	default:
	pr_err("Unrecognized Control Frame\n");
	goto error;
	break;
	}
	ret = 0;
	error:
	cfpkt_destroy(pkt);
	return ret;
	}

	static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
	int phyid)
	{
	struct cfctrl *this = container_obj(layr);
	switch (ctrl) {
	case _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND:
	case CAIF_CTRLCMD_FLOW_OFF_IND:
	spin_lock_bh(&this->info_list_lock);
	if (!list_empty(&this->list))
	pr_debug("Received flow off in control layer\n");
	spin_unlock_bh(&this->info_list_lock);
	break;
	case _CAIF_CTRLCMD_PHYIF_DOWN_IND: {
	struct cfctrl_request_info p, tmp;

	/* Find all connect request and report failure */
	spin_lock_bh(&this->info_list_lock);
	list_for_each_entry_safe(p, tmp, &this->list, list) {
	if (p->param.phyid == phyid) {
	list_del(&p->list);
	p->client_layer->ctrlcmd(p->client_layer,
	CAIF_CTRLCMD_INIT_FAIL_RSP,
	phyid);
	kfree(p);
	}
	}
	spin_unlock_bh(&this->info_list_lock);
	break;
	}
	default:
	break;
	}
	}

	#ifndef CAIF_NO_LOOP
	static int handle_loop(struct cfctrl ctrl, int cmd, struct cfpkt pkt)
	{
	static int last_linkid;
	static int dec;
	u8 linkid, linktype, tmp;
	switch (cmd) {
	case CFCTRL_CMD_LINK_SETUP:
	spin_lock_bh(&ctrl->loop_linkid_lock);
	if (!dec) {
	for (linkid = last_linkid + 1; linkid < 254; linkid++)
	if (!ctrl->loop_linkused[linkid])
	goto found;
	}
	dec = 1;
	for (linkid = last_linkid - 1; linkid > 1; linkid--)
	if (!ctrl->loop_linkused[linkid])
	goto found;
	spin_unlock_bh(&ctrl->loop_linkid_lock);
	return -1;
	found:
	if (linkid < 10)
	dec = 0;

	if (!ctrl->loop_linkused[linkid])
	ctrl->loop_linkused[linkid] = 1;

	last_linkid = linkid;

	cfpkt_add_trail(pkt, &linkid, 1);
	spin_unlock_bh(&ctrl->loop_linkid_lock);
	cfpkt_peek_head(pkt, &linktype, 1);
	if (linktype == CFCTRL_SRV_UTIL) {
	tmp = 0x01;
	cfpkt_add_trail(pkt, &tmp, 1);
	cfpkt_add_trail(pkt, &tmp, 1);
	}
	break;

	case CFCTRL_CMD_LINK_DESTROY:
	spin_lock_bh(&ctrl->loop_linkid_lock);
	cfpkt_peek_head(pkt, &linkid, 1);
	ctrl->loop_linkused[linkid] = 0;
	spin_unlock_bh(&ctrl->loop_linkid_lock);
	break;
	default:
	break;
	}
	return 0;
	}
	#endif