/*
   * Copyright (C) ST-Ericsson AB 2010

   * Author:	Sjur Brendeland

   * License terms: GNU General Public License (GPL) version 2
   */

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

  #include <linux/stddef.h>
  #include <linux/slab.h>
  #include <net/caif/caif_layer.h>
  #include <net/caif/cfsrvl.h>
  #include <net/caif/cfpkt.h>
  
  #define VEI_PAYLOAD  0x00
  #define VEI_CMD_BIT  0x80
  #define VEI_FLOW_OFF 0x81
  #define VEI_FLOW_ON  0x80
  #define VEI_SET_PIN  0x82

  #define container_obj(layr) container_of(layr, struct cfsrvl, layer)
  
  static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt);
  static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt);
  
  struct cflayer *cfvei_create(u8 channel_id, struct dev_info *dev_info)
  {

  	struct cfsrvl *vei = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
  	if (!vei)

  		return NULL;

  	caif_assert(offsetof(struct cfsrvl, layer) == 0);

  	cfsrvl_init(vei, channel_id, dev_info, true);

  	vei->layer.receive = cfvei_receive;
  	vei->layer.transmit = cfvei_transmit;
  	snprintf(vei->layer.name, CAIF_LAYER_NAME_SZ - 1, "vei%d", channel_id);
  	return &vei->layer;
  }
  
  static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt)
  {
  	u8 cmd;
  	int ret;
  	caif_assert(layr->up != NULL);
  	caif_assert(layr->receive != NULL);
  	caif_assert(layr->ctrlcmd != NULL);
  
  
  	if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {

  		pr_err("Packet is erroneous!
  ");

  		cfpkt_destroy(pkt);
  		return -EPROTO;
  	}
  	switch (cmd) {
  	case VEI_PAYLOAD:
  		ret = layr->up->receive(layr->up, pkt);
  		return ret;
  	case VEI_FLOW_OFF:
  		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
  		cfpkt_destroy(pkt);
  		return 0;
  	case VEI_FLOW_ON:
  		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
  		cfpkt_destroy(pkt);
  		return 0;
  	case VEI_SET_PIN:	/* SET RS232 PIN */
  		cfpkt_destroy(pkt);
  		return 0;
  	default:		/* SET RS232 PIN */

  		pr_warn("Unknown VEI control packet %d (0x%x)!
  ", cmd, cmd);

  		cfpkt_destroy(pkt);
  		return -EPROTO;
  	}
  }
  
  static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt)
  {
  	u8 tmp = 0;
  	struct caif_payload_info *info;
  	int ret;
  	struct cfsrvl *service = container_obj(layr);
  	if (!cfsrvl_ready(service, &ret))

  		goto err;

  	caif_assert(layr->dn != NULL);
  	caif_assert(layr->dn->transmit != NULL);

  
  	if (cfpkt_add_head(pkt, &tmp, 1) < 0) {

  		pr_err("Packet is erroneous!
  ");

  		ret = -EPROTO;
  		goto err;

  	}
  
  	/* Add info-> for MUX-layer to route the packet out. */
  	info = cfpkt_info(pkt);
  	info->channel_id = service->layer.id;
  	info->hdr_len = 1;
  	info->dev_info = &service->dev_info;

  	return layr->dn->transmit(layr->dn, pkt);

  err:
  	cfpkt_destroy(pkt);
  	return ret;

  }