/* r3964 linediscipline for linux
   *
   * -----------------------------------------------------------
   * Copyright by
   * Philips Automation Projects
   * Kassel (Germany)

   * -----------------------------------------------------------
   * This software may be used and distributed according to the terms of
   * the GNU General Public License, incorporated herein by reference.
   *
   * Author:
   * L. Haag
   *
   * $Log: r3964.h,v $

   * Revision 1.4  2005/12/21 19:54:24  Kurt Huwig <kurt huwig de>
   * Fixed HZ usage on 2.6 kernels
   * Removed unnecessary include
   *

   * Revision 1.3  2001/03/18 13:02:24  dwmw2
   * Fix timer usage, use spinlocks properly.
   *
   * Revision 1.2  2001/03/18 12:53:15  dwmw2
   * Merge changes in 2.4.2
   *
   * Revision 1.1.1.1  1998/10/13 16:43:14  dwmw2
   * This'll screw the version control
   *
   * Revision 1.6  1998/09/30 00:40:38  dwmw2
   * Updated to use kernel's N_R3964 if available
   *
   * Revision 1.4  1998/04/02 20:29:44  lhaag
   * select, blocking, ...
   *
   * Revision 1.3  1998/02/12 18:58:43  root
   * fixed some memory leaks
   * calculation of checksum characters
   *
   * Revision 1.2  1998/02/07 13:03:17  root
   * ioctl read_telegram
   *
   * Revision 1.1  1998/02/06 19:19:43  root
   * Initial revision
   *
   *
   */

  #ifndef __LINUX_N_R3964_H__
  #define __LINUX_N_R3964_H__

  
  #include <linux/param.h>

  #include <uapi/linux/n_r3964.h>

  /*
   * Common ascii handshake characters:
   */
  
  #define STX 0x02
  #define ETX 0x03
  #define DLE 0x10
  #define NAK 0x15
  
  /*

   * Timeouts (from milliseconds to jiffies)

   */

  #define R3964_TO_QVZ ((550)*HZ/1000)
  #define R3964_TO_ZVZ ((220)*HZ/1000)
  #define R3964_TO_NO_BUF ((400)*HZ/1000)
  #define R3964_NO_TX_ROOM ((100)*HZ/1000)
  #define R3964_TO_RX_PANIC ((4000)*HZ/1000)

  #define R3964_MAX_RETRIES 5

  
  enum { R3964_IDLE, 
  	   R3964_TX_REQUEST, R3964_TRANSMITTING, 
  	   R3964_WAIT_ZVZ_BEFORE_TX_RETRY, R3964_WAIT_FOR_TX_ACK,
  	   R3964_WAIT_FOR_RX_BUF,
  	   R3964_RECEIVING, R3964_WAIT_FOR_BCC, R3964_WAIT_FOR_RX_REPEAT
  	   };
  
  /*
   * All open file-handles are 'clients' and are stored in a linked list:
   */
  
  struct r3964_message;
  
  struct r3964_client_info {
  	spinlock_t     lock;

  	struct pid    *pid;

  	unsigned int   sig_flags;
  
  	struct r3964_client_info *next;
  
  	struct r3964_message *first_msg;
  	struct r3964_message *last_msg;
  	struct r3964_block_header *next_block_to_read;
  	int            msg_count;
  };

  
  struct r3964_block_header;
  
  /* internal version of client_message: */
  struct r3964_message {
  	  int     msg_id;
  	  int     arg;
  	  int     error_code;
  	  struct r3964_block_header *block;
  	  struct r3964_message *next;
  };
  
  /*
   * Header of received block in rx_buf/tx_buf:
   */
  
  struct r3964_block_header 
  {
  	unsigned int length;             /* length in chars without header */
  	unsigned char *data;             /* usually data is located 
                                          immediately behind this struct */
  	unsigned int locks;              /* only used in rx_buffer */
  	  
      struct r3964_block_header *next;
  	struct r3964_client_info *owner;  /* =NULL in rx_buffer */
  };
  
  /*
   * If rx_buf hasn't enough space to store R3964_MTU chars,
   * we will reject all incoming STX-requests by sending NAK.
   */
  
  #define RX_BUF_SIZE    4000
  #define TX_BUF_SIZE    4000
  #define R3964_MAX_BLOCKS_IN_RX_QUEUE 100
  
  #define R3964_PARITY 0x0001
  #define R3964_FRAME  0x0002
  #define R3964_OVERRUN 0x0004
  #define R3964_UNKNOWN 0x0008
  #define R3964_BREAK   0x0010
  #define R3964_CHECKSUM 0x0020
  #define R3964_ERROR  0x003f
  #define R3964_BCC   0x4000
  #define R3964_DEBUG 0x8000
  
  
  struct r3964_info {
  	spinlock_t     lock;
  	struct tty_struct *tty;
  	unsigned char priority;
  	unsigned char *rx_buf;            /* ring buffer */
  	unsigned char *tx_buf;

  	struct r3964_block_header *rx_first;
  	struct r3964_block_header *rx_last;
  	struct r3964_block_header *tx_first;
  	struct r3964_block_header *tx_last;
  	unsigned int tx_position;
          unsigned int rx_position;
  	unsigned char last_rx;
  	unsigned char bcc;
          unsigned int  blocks_in_rx_queue;

  
  	struct mutex read_lock;		/* serialize r3964_read */

  	struct r3964_client_info *firstClient;
  	unsigned int state;
  	unsigned int flags;
  
  	struct timer_list tmr;
  	int nRetry;
  };

  #endif