sdla_x25.c

linux-2.6.15.6

/*****************************************************************************
* sdla_x25.c	WANPIPE(tm) Multiprotocol WAN Link Driver.  X.25 module.
*
* Author:	Nenad Corbic	<[e-mail]>
*
* Copyright:	(c) 1995-2001 Sangoma Technologies Inc.
*
*		This program is free software; you can redistribute it and/or
*		modify it under the terms of the GNU General Public License
*		as published by the Free Software Foundation; either version
*		2 of the License, or (at your option) any later version.
* ============================================================================
* Apr 03, 2001  Nenad Corbic	 o Fixed the rx_skb=NULL bug in x25 in rx_intr().
* Dec 26, 2000  Nenad Corbic	 o Added a new polling routine, that uses
*                                  a kernel timer (more efficient).
* Dec 25, 2000  Nenad Corbic	 o Updated for 2.4.X kernel
* Jul 26, 2000  Nenad Corbic	 o Increased the local packet buffering
* 				   for API to 4096+header_size. 
* Jul 17, 2000  Nenad Corbic	 o Fixed the x25 startup bug. Enable 
* 				   communications only after all interfaces
* 				   come up.  HIGH SVC/PVC is used to calculate
* 				   the number of channels.
*                                  Enable protocol only after all interfaces
*                                  are enabled.
* Jul 10, 2000	Nenad Corbic	 o Fixed the M_BIT bug. 
* Apr 25, 2000  Nenad Corbic	 o Pass Modem messages to the API.
*                                  Disable idle timeout in X25 API.
* Apr 14, 2000  Nenad Corbic	 o Fixed: Large LCN number support.
*                                  Maximum LCN number is 4095.
*                                  Maximum number of X25 channels is 255.
* Apr 06, 2000  Nenad Corbic	 o Added SMP Support.
* Mar 29, 2000  Nenad Corbic	 o Added support for S514 PCI Card
* Mar 23, 2000  Nenad Corbic	 o Improved task queue, BH handling.
* Mar 14, 2000  Nenad Corbic  	 o Updated Protocol Violation handling
*                                  routines.  Bug Fix.
* Mar 10, 2000  Nenad Corbic	 o Bug Fix: corrupted mbox recovery.
* Mar 09, 2000  Nenad Corbic     o Fixed the auto HDLC bug.
* Mar 08, 2000	Nenad Corbic     o Fixed LAPB HDLC startup problems.
*                                  Application must bring the link up 
*                                  before tx/rx, and bring the 
*                                  link down on close().
* Mar 06, 2000	Nenad Corbic	 o Added an option for logging call setup 
*                                  information. 
* Feb 29, 2000  Nenad Corbic 	 o Added support for LAPB HDLC API
* Feb 25, 2000  Nenad Corbic     o Fixed the modem failure handling.
*                                  No Modem OOB message will be passed 
*                                  to the user.
* Feb 21, 2000  Nenad Corbic 	 o Added Xpipemon Debug Support
* Dec 30, 1999 	Nenad Corbic	 o Socket based X25API 
* Sep 17, 1998	Jaspreet Singh	 o Updates for 2.2.X  kernel
* Mar 15, 1998	Alan Cox	 o 2.1.x porting
* Dec 19, 1997	Jaspreet Singh	 o Added multi-channel IPX support
* Nov 27, 1997	Jaspreet Singh	 o Added protection against enabling of irqs
*				   when they are disabled.
* Nov 17, 1997  Farhan Thawar    o Added IPX support
*				 o Changed if_send() to now buffer packets when
*				   the board is busy
*				 o Removed queueing of packets via the polling
*				   routing
*				 o Changed if_send() critical flags to properly
*				   handle race conditions
* Nov 06, 1997  Farhan Thawar    o Added support for SVC timeouts
*				 o Changed PVC encapsulation to ETH_P_IP
* Jul 21, 1997  Jaspreet Singh	 o Fixed freeing up of buffers using kfree()
*				   when packets are received.
* Mar 11, 1997  Farhan Thawar   Version 3.1.1
*                                o added support for V35
*                                o changed if_send() to return 0 if
*                                  wandev.critical() is true
*                                o free socket buffer in if_send() if
*                                  returning 0
*                                o added support for single '@' address to
*                                  accept all incoming calls
*                                o fixed bug in set_chan_state() to disconnect
* Jan 15, 1997	Gene Kozin	Version 3.1.0
*				 o implemented exec() entry point
* Jan 07, 1997	Gene Kozin	Initial version.
*****************************************************************************/

/*======================================================
 * 	Includes 
 *=====================================================*/

#include <linux/module.h>
#include <linux/kernel.h>	/* printk(), and other useful stuff */
#include <linux/stddef.h>	/* offsetof(), etc. */
#include <linux/errno.h>	/* return codes */
#include <linux/string.h>	/* inline memset(), etc. */
#include <linux/ctype.h>
#include <linux/slab.h>	/* kmalloc(), kfree() */
#include <linux/wanrouter.h>	/* WAN router definitions */
#include <linux/wanpipe.h>	/* WANPIPE common user API definitions */
#include <linux/workqueue.h>
#include <linux/jiffies.h>	/* time_after() macro */
#include <asm/byteorder.h>	/* htons(), etc. */
#include <asm/atomic.h>
#include <linux/delay.h>	/* Experimental delay */

#include <asm/uaccess.h>

#include <linux/if.h>
#include <linux/if_arp.h>
#include <linux/sdla_x25.h>	/* X.25 firmware API definitions */
#include <linux/if_wanpipe_common.h>
#include <linux/if_wanpipe.h>


/*======================================================
 * 	Defines & Macros 
 *=====================================================*/


#define	CMD_OK		0		/* normal firmware return code */
#define	CMD_TIMEOUT	0xFF		/* firmware command timed out */
#define	MAX_CMD_RETRY	10		/* max number of firmware retries */

#define	X25_CHAN_MTU	4096		/* unfragmented logical channel MTU */
#define	X25_HRDHDR_SZ	7		/* max encapsulation header size */
#define	X25_CONCT_TMOUT	(90*HZ)		/* link connection timeout */
#define	X25_RECON_TMOUT	(10*HZ)		/* link connection timeout */
#define	CONNECT_TIMEOUT	(90*HZ)		/* link connection timeout */
#define	HOLD_DOWN_TIME	(30*HZ)		/* link hold down time */
#define MAX_BH_BUFF	10
#define M_BIT		0x01	

//#define PRINT_DEBUG 1
#ifdef PRINT_DEBUG
#define DBG_PRINTK(format, a...) printk(format, ## a)
#else
#define DBG_PRINTK(format, a...)
#endif  

#define TMR_INT_ENABLED_POLL_ACTIVE      0x01
#define TMR_INT_ENABLED_POLL_CONNECT_ON  0x02
#define TMR_INT_ENABLED_POLL_CONNECT_OFF 0x04
#define TMR_INT_ENABLED_POLL_DISCONNECT  0x08
#define TMR_INT_ENABLED_CMD_EXEC	 0x10
#define TMR_INT_ENABLED_UPDATE		 0x20
#define TMR_INT_ENABLED_UDP_PKT		 0x40

#define MAX_X25_ADDR_SIZE	16
#define MAX_X25_DATA_SIZE 	129
#define MAX_X25_FACL_SIZE	110

#define TRY_CMD_AGAIN	2
#define DELAY_RESULT    1
#define RETURN_RESULT   0

#define DCD(x) (x & 0x03 ? "HIGH" : "LOW")
#define CTS(x) (x & 0x05 ? "HIGH" : "LOW")


/* Driver will not write log messages about 
 * modem status if defined.*/
#define MODEM_NOT_LOG 1

/*==================================================== 
 * 	For IPXWAN 
 *===================================================*/

#define CVHexToAscii(b) (((unsigned char)(b) > (unsigned char)9) ? ((unsigned char)'A' + ((unsigned char)(b) - (unsigned char)10)) : ((unsigned char)'0' + (unsigned char)(b)))


/*====================================================
 *           MEMORY DEBUGGING FUNCTION
 *====================================================

#define KMEM_SAFETYZONE 8

static void * dbg_kmalloc(unsigned int size, int prio, int line) {
	int i = 0;
	void * v = kmalloc(size+sizeof(unsigned int)+2*KMEM_SAFETYZONE*8,prio);
	char * c1 = v;	
	c1 += sizeof(unsigned int);
	*((unsigned int *)v) = size;

	for (i = 0; i < KMEM_SAFETYZONE; i++) {
		c1[0] = 'D'; c1[1] = 'E'; c1[2] = 'A'; c1[3] = 'D';
		c1[4] = 'B'; c1[5] = 'E'; c1[6] = 'E'; c1[7] = 'F';
		c1 += 8;
	}
	c1 += size;
	for (i = 0; i < KMEM_SAFETYZONE; i++) {
		c1[0] = 'M'; c1[1] = 'U'; c1[2] = 'N'; c1[3] = 'G';
		c1[4] = 'W'; c1[5] = 'A'; c1[6] = 'L'; c1[7] = 'L';
		c1 += 8;
	}
	v = ((char *)v) + sizeof(unsigned int) + KMEM_SAFETYZONE*8;
	printk(KERN_INFO "line %d  kmalloc(%d,%d) = %p\n",line,size,prio,v);
	return v;
}
static void dbg_kfree(void * v, int line) {
	unsigned int * sp = (unsigned int *)(((char *)v) - (sizeof(unsigned int) + KMEM_SAFETYZONE*8));
	unsigned int size = *sp;
	char * c1 = ((char *)v) - KMEM_SAFETYZONE*8;
	int i = 0;
	for (i = 0; i < KMEM_SAFETYZONE; i++) {
		if (   c1[0] != 'D' || c1[1] != 'E' || c1[2] != 'A' || c1[3] != 'D'
		    || c1[4] != 'B' || c1[5] != 'E' || c1[6] != 'E' || c1[7] != 'F') {
			printk(KERN_INFO "kmalloced block at %p has been corrupted (underrun)!\n",v);
			printk(KERN_INFO " %4x: %2x %2x %2x %2x %2x %2x %2x %2x\n", i*8,
			                c1[0],c1[1],c1[2],c1[3],c1[4],c1[5],c1[6],c1[7] );
		}
		c1 += 8;
	}
	c1 += size;
	for (i = 0; i < KMEM_SAFETYZONE; i++) {
		if (   c1[0] != 'M' || c1[1] != 'U' || c1[2] != 'N' || c1[3] != 'G'
		    || c1[4] != 'W' || c1[5] != 'A' || c1[6] != 'L' || c1[7] != 'L'
		   ) {
			printk(KERN_INFO "kmalloced block at %p has been corrupted (overrun):\n",v);
			printk(KERN_INFO " %4x: %2x %2x %2x %2x %2x %2x %2x %2x\n", i*8,
			                c1[0],c1[1],c1[2],c1[3],c1[4],c1[5],c1[6],c1[7] );
		}
		c1 += 8;
	}
	printk(KERN_INFO "line %d  kfree(%p)\n",line,v);
	v = ((char *)v) - (sizeof(unsigned int) + KMEM_SAFETYZONE*8);
	kfree(v);
}

#define kmalloc(x,y) dbg_kmalloc(x,y,__LINE__)
#define kfree(x) dbg_kfree(x,__LINE__)

==============================================================*/



/*===============================================
 * 	Data Structures 
 *===============================================*/


/*========================================================
 * Name: 	x25_channel
 *
 * Purpose:	To hold private informaton for each  
 *              logical channel.
 *		
 * Rationale:  	Per-channel debugging is possible if each 
 *              channel has its own private area.
 *	
 * Assumptions:
 *
 * Description:	This is an extention of the struct net_device
 *              we create for each network interface to keep 
 *              the rest of X.25 channel-specific data. 
 *
 * Construct:	Typedef
 */
typedef struct x25_channel
{
	wanpipe_common_t common;	/* common area for x25api and socket */
	char name[WAN_IFNAME_SZ+1];	/* interface name, ASCIIZ */
	char addr[WAN_ADDRESS_SZ+1];	/* media address, ASCIIZ */
	unsigned tx_pkt_size;
	unsigned short protocol;	/* ethertype, 0 - multiplexed */
	char drop_sequence;		/* mark sequence for dropping */
	unsigned long state_tick;	/* time of the last state change */
	unsigned idle_timeout;		/* sec, before disconnecting */
	unsigned long i_timeout_sofar;  /* # of sec's we've been idle */
	unsigned hold_timeout;		/* sec, before re-connecting */
	unsigned long tick_counter;	/* counter for transmit time out */
	char devtint;			/* Weather we should dev_tint() */
	struct sk_buff* rx_skb;		/* receive socket buffer */
	struct sk_buff* tx_skb;		/* transmit socket buffer */

	bh_data_t *bh_head;	  	  /* Circular buffer for x25api_bh */
	unsigned long  tq_working;
	volatile int  bh_write;
	volatile int  bh_read;
	atomic_t  bh_buff_used;

	sdla_t* card;			/* -> owner */
	struct net_device *dev;		/* -> bound devce */

	int ch_idx;
	unsigned char enable_IPX;
	unsigned long network_number;
	struct net_device_stats ifstats;	/* interface statistics */
	unsigned short transmit_length;
	unsigned short tx_offset;
	char transmit_buffer[X25_CHAN_MTU+sizeof(x25api_hdr_t)];

	if_send_stat_t   if_send_stat;
        rx_intr_stat_t   rx_intr_stat;
        pipe_mgmt_stat_t pipe_mgmt_stat;    

	unsigned long router_start_time; /* Router start time in seconds */
	unsigned long router_up_time;
	
} x25_channel_t;

/* FIXME Take this out */

#ifdef NEX_OLD_CALL_INFO
typedef struct x25_call_info
{
	char dest[17];			PACKED;/* ASCIIZ destination address */
	char src[17];			PACKED;/* ASCIIZ source address */
	char nuser;			PACKED;/* number of user data bytes */
	unsigned char user[127];	PACKED;/* user data */
	char nfacil;			PACKED;/* number of facilities */
	struct
	{
		unsigned char code;     PACKED;
		unsigned char parm;     PACKED;
	} facil[64];			        /* facilities */
} x25_call_info_t;
#else
typedef struct x25_call_info
{
	char dest[MAX_X25_ADDR_SIZE]		PACKED;/* ASCIIZ destination address */
	char src[MAX_X25_ADDR_SIZE]		PACKED;/* ASCIIZ source address */
	unsigned char nuser			PACKED;
	unsigned char user[MAX_X25_DATA_SIZE]	PACKED;/* user data */
	unsigned char nfacil			PACKED;
	unsigned char facil[MAX_X25_FACL_SIZE]	PACKED;
	unsigned short lcn             		PACKED;
} x25_call_info_t;
#endif


  
/*===============================================
 *	Private Function Prototypes
 *==============================================*/


/*================================================= 
 * WAN link driver entry points. These are 
 * called by the WAN router module.
 */
static int update(struct wan_device* wandev);
static int new_if(struct wan_device* wandev, struct net_device* dev,
		  wanif_conf_t* conf);
static int del_if(struct wan_device* wandev, struct net_device* dev);
static void disable_comm (sdla_t* card);
static void disable_comm_shutdown(sdla_t *card);



/*================================================= 
 *	WANPIPE-specific entry points 
 */
static int wpx_exec (struct sdla* card, void* u_cmd, void* u_data);
static void x25api_bh(struct net_device *dev);
static int x25api_bh_cleanup(struct net_device *dev);
static int bh_enqueue(struct net_device *dev, struct sk_buff *skb);


/*=================================================  
 * 	Network device interface 
 */
static int if_init(struct net_device* dev);
static int if_open(struct net_device* dev);
static int if_close(struct net_device* dev);
static int if_header(struct sk_buff* skb, struct net_device* dev,
	unsigned short type, void* daddr, void* saddr, unsigned len);
static int if_rebuild_hdr (struct sk_buff* skb);
static int if_send(struct sk_buff* skb, struct net_device* dev);
static struct net_device_stats *if_stats(struct net_device* dev);

static void if_tx_timeout(struct net_device *dev);

/*=================================================  
 * 	Interrupt handlers 
 */
static void wpx_isr	(sdla_t *);
static void rx_intr	(sdla_t *);
static void tx_intr	(sdla_t *);
static void status_intr	(sdla_t *);
static void event_intr	(sdla_t *);
static void spur_intr	(sdla_t *);
static void timer_intr  (sdla_t *);

static int tx_intr_send(sdla_t *card, struct net_device *dev);
static struct net_device *move_dev_to_next(sdla_t *card,
					   struct net_device *dev);

/*=================================================  
 *	Background polling routines 
 */
static void wpx_poll (sdla_t* card);
static void poll_disconnected (sdla_t* card);
static void poll_connecting (sdla_t* card);
static void poll_active (sdla_t* card);
static void trigger_x25_poll(sdla_t *card);
static void x25_timer_routine(unsigned long data);



/*=================================================  
 *	X.25 firmware interface functions 
 */
static int x25_get_version (sdla_t* card, char* str);
static int x25_configure (sdla_t* card, TX25Config* conf);
static int hdlc_configure (sdla_t* card, TX25Config* conf);
static int set_hdlc_level (sdla_t* card);
static int x25_get_err_stats (sdla_t* card);
static int x25_get_stats (sdla_t* card);
static int x25_set_intr_mode (sdla_t* card, int mode);
static int x25_close_hdlc (sdla_t* card);
static int x25_open_hdlc (sdla_t* card);
static int x25_setup_hdlc (sdla_t* card);
static int x25_set_dtr (sdla_t* card, int dtr);
static int x25_get_chan_conf (sdla_t* card, x25_channel_t* chan);
static int x25_place_call (sdla_t* card, x25_channel_t* chan);
static int x25_accept_call (sdla_t* card, int lcn, int qdm);
static int x25_clear_call (sdla_t* card, int lcn, int cause, int diagn);
static int x25_send (sdla_t* card, int lcn, int qdm, int len, void* buf);
static int x25_fetch_events (sdla_t* card);
static int x25_error (sdla_t* card, int err, int cmd, int lcn);

/*=================================================  
 *	X.25 asynchronous event handlers 
 */
static int incoming_call (sdla_t* card, int cmd, int lcn, TX25Mbox* mb);
static int call_accepted (sdla_t* card, int cmd, int lcn, TX25Mbox* mb);
static int call_cleared (sdla_t* card, int cmd, int lcn, TX25Mbox* mb);
static int timeout_event (sdla_t* card, int cmd, int lcn, TX25Mbox* mb);
static int restart_event (sdla_t* card, int cmd, int lcn, TX25Mbox* mb);


/*=================================================  
 *	Miscellaneous functions 
 */
static int connect (sdla_t* card);
static int disconnect (sdla_t* card);
static struct net_device* get_dev_by_lcn(struct wan_device* wandev,
					 unsigned lcn);
static int chan_connect(struct net_device* dev);
static int chan_disc(struct net_device* dev);
static void set_chan_state(struct net_device* dev, int state);
static int chan_send(struct net_device *dev, void* buff, unsigned data_len,
		     unsigned char tx_intr);
static unsigned char bps_to_speed_code (unsigned long bps);
static unsigned int dec_to_uint (unsigned char* str, int len);