/* 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;

wait_queue_head_t read_wait;
//struct wait_queue *read_wait;

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 r3964_client_info *firstClient;
unsigned int state;
unsigned int flags;

struct timer_list tmr;
int nRetry;
};

#endif