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		c9f19e96a2
		
	
	
	
	
		
			
			disc_data and driver_data are void * Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			1263 lines
		
	
	
		
			31 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1263 lines
		
	
	
		
			31 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* r3964 linediscipline for linux
 | |
|  *
 | |
|  * -----------------------------------------------------------
 | |
|  * Copyright by 
 | |
|  * Philips Automation Projects
 | |
|  * Kassel (Germany)
 | |
|  * http://www.pap-philips.de
 | |
|  * -----------------------------------------------------------
 | |
|  * 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: n_r3964.c,v $
 | |
|  * Revision 1.10  2001/03/18 13:02:24  dwmw2
 | |
|  * Fix timer usage, use spinlocks properly.
 | |
|  *
 | |
|  * Revision 1.9  2001/03/18 12:52:14  dwmw2
 | |
|  * Merge changes in 2.4.2
 | |
|  *
 | |
|  * Revision 1.8  2000/03/23 14:14:54  dwmw2
 | |
|  * Fix race in sleeping in r3964_read()
 | |
|  *
 | |
|  * Revision 1.7  1999/28/08 11:41:50  dwmw2
 | |
|  * Port to 2.3 kernel
 | |
|  *
 | |
|  * Revision 1.6  1998/09/30 00:40:40  dwmw2
 | |
|  * Fixed compilation on 2.0.x kernels
 | |
|  * Updated to newly registered tty-ldisc number 9
 | |
|  *
 | |
|  * Revision 1.5  1998/09/04 21:57:36  dwmw2
 | |
|  * Signal handling bug fixes, port to 2.1.x.
 | |
|  *
 | |
|  * Revision 1.4  1998/04/02 20:26:59  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 13:03:34  root
 | |
|  * ioctl read_telegram
 | |
|  *
 | |
|  * Revision 1.1  1998/02/06 19:21:03  root
 | |
|  * Initial revision
 | |
|  *
 | |
|  *
 | |
|  */
 | |
| 
 | |
| #include <linux/module.h>
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/sched.h>
 | |
| #include <linux/types.h>
 | |
| #include <linux/fcntl.h>
 | |
| #include <linux/interrupt.h>
 | |
| #include <linux/ptrace.h>
 | |
| #include <linux/ioport.h>
 | |
| #include <linux/in.h>
 | |
| #include <linux/slab.h>
 | |
| #include <linux/tty.h>
 | |
| #include <linux/errno.h>
 | |
| #include <linux/string.h>	/* used in new tty drivers */
 | |
| #include <linux/signal.h>	/* used in new tty drivers */
 | |
| #include <linux/ioctl.h>
 | |
| #include <linux/n_r3964.h>
 | |
| #include <linux/poll.h>
 | |
| #include <linux/init.h>
 | |
| #include <asm/uaccess.h>
 | |
| 
 | |
| /*#define DEBUG_QUEUE*/
 | |
| 
 | |
| /* Log successful handshake and protocol operations  */
 | |
| /*#define DEBUG_PROTO_S*/
 | |
| 
 | |
| /* Log handshake and protocol errors: */
 | |
| /*#define DEBUG_PROTO_E*/
 | |
| 
 | |
| /* Log Linediscipline operations (open, close, read, write...): */
 | |
| /*#define DEBUG_LDISC*/
 | |
| 
 | |
| /* Log module and memory operations (init, cleanup; kmalloc, kfree): */
 | |
| /*#define DEBUG_MODUL*/
 | |
| 
 | |
| /* Macro helpers for debug output: */
 | |
| #define TRACE(format, args...) printk("r3964: " format "\n" , ## args)
 | |
| 
 | |
| #ifdef DEBUG_MODUL
 | |
| #define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args)
 | |
| #else
 | |
| #define TRACE_M(fmt, arg...) do {} while (0)
 | |
| #endif
 | |
| #ifdef DEBUG_PROTO_S
 | |
| #define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args)
 | |
| #else
 | |
| #define TRACE_PS(fmt, arg...) do {} while (0)
 | |
| #endif
 | |
| #ifdef DEBUG_PROTO_E
 | |
| #define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args)
 | |
| #else
 | |
| #define TRACE_PE(fmt, arg...) do {} while (0)
 | |
| #endif
 | |
| #ifdef DEBUG_LDISC
 | |
| #define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args)
 | |
| #else
 | |
| #define TRACE_L(fmt, arg...) do {} while (0)
 | |
| #endif
 | |
| #ifdef DEBUG_QUEUE
 | |
| #define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args)
 | |
| #else
 | |
| #define TRACE_Q(fmt, arg...) do {} while (0)
 | |
| #endif
 | |
| static void add_tx_queue(struct r3964_info *, struct r3964_block_header *);
 | |
| static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code);
 | |
| static void put_char(struct r3964_info *pInfo, unsigned char ch);
 | |
| static void trigger_transmit(struct r3964_info *pInfo);
 | |
| static void retry_transmit(struct r3964_info *pInfo);
 | |
| static void transmit_block(struct r3964_info *pInfo);
 | |
| static void receive_char(struct r3964_info *pInfo, const unsigned char c);
 | |
| static void receive_error(struct r3964_info *pInfo, const char flag);
 | |
| static void on_timeout(unsigned long priv);
 | |
| static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg);
 | |
| static int read_telegram(struct r3964_info *pInfo, struct pid *pid,
 | |
| 		unsigned char __user * buf);
 | |
| static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg,
 | |
| 		int error_code, struct r3964_block_header *pBlock);
 | |
| static struct r3964_message *remove_msg(struct r3964_info *pInfo,
 | |
| 		struct r3964_client_info *pClient);
 | |
| static void remove_client_block(struct r3964_info *pInfo,
 | |
| 		struct r3964_client_info *pClient);
 | |
| 
 | |
| static int r3964_open(struct tty_struct *tty);
 | |
| static void r3964_close(struct tty_struct *tty);
 | |
| static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 | |
| 		unsigned char __user * buf, size_t nr);
 | |
| static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
 | |
| 		const unsigned char *buf, size_t nr);
 | |
| static int r3964_ioctl(struct tty_struct *tty, struct file *file,
 | |
| 		unsigned int cmd, unsigned long arg);
 | |
| static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old);
 | |
| static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
 | |
| 		struct poll_table_struct *wait);
 | |
| static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
 | |
| 		char *fp, int count);
 | |
| 
 | |
| static struct tty_ldisc_ops tty_ldisc_N_R3964 = {
 | |
| 	.owner = THIS_MODULE,
 | |
| 	.magic = TTY_LDISC_MAGIC,
 | |
| 	.name = "R3964",
 | |
| 	.open = r3964_open,
 | |
| 	.close = r3964_close,
 | |
| 	.read = r3964_read,
 | |
| 	.write = r3964_write,
 | |
| 	.ioctl = r3964_ioctl,
 | |
| 	.set_termios = r3964_set_termios,
 | |
| 	.poll = r3964_poll,
 | |
| 	.receive_buf = r3964_receive_buf,
 | |
| };
 | |
| 
 | |
| static void dump_block(const unsigned char *block, unsigned int length)
 | |
| {
 | |
| 	unsigned int i, j;
 | |
| 	char linebuf[16 * 3 + 1];
 | |
| 
 | |
| 	for (i = 0; i < length; i += 16) {
 | |
| 		for (j = 0; (j < 16) && (j + i < length); j++) {
 | |
| 			sprintf(linebuf + 3 * j, "%02x ", block[i + j]);
 | |
| 		}
 | |
| 		linebuf[3 * j] = '\0';
 | |
| 		TRACE_PS("%s", linebuf);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| /*************************************************************
 | |
|  * Driver initialisation
 | |
|  *************************************************************/
 | |
| 
 | |
| /*************************************************************
 | |
|  * Module support routines
 | |
|  *************************************************************/
 | |
| 
 | |
| static void __exit r3964_exit(void)
 | |
| {
 | |
| 	int status;
 | |
| 
 | |
| 	TRACE_M("cleanup_module()");
 | |
| 
 | |
| 	status = tty_unregister_ldisc(N_R3964);
 | |
| 
 | |
| 	if (status != 0) {
 | |
| 		printk(KERN_ERR "r3964: error unregistering linediscipline: "
 | |
| 				"%d\n", status);
 | |
| 	} else {
 | |
| 		TRACE_L("linediscipline successfully unregistered");
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static int __init r3964_init(void)
 | |
| {
 | |
| 	int status;
 | |
| 
 | |
| 	printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n");
 | |
| 
 | |
| 	/*
 | |
| 	 * Register the tty line discipline
 | |
| 	 */
 | |
| 
 | |
| 	status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964);
 | |
| 	if (status == 0) {
 | |
| 		TRACE_L("line discipline %d registered", N_R3964);
 | |
| 		TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags,
 | |
| 			tty_ldisc_N_R3964.num);
 | |
| 		TRACE_L("open=%p", tty_ldisc_N_R3964.open);
 | |
| 		TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964);
 | |
| 	} else {
 | |
| 		printk(KERN_ERR "r3964: error registering line discipline: "
 | |
| 				"%d\n", status);
 | |
| 	}
 | |
| 	return status;
 | |
| }
 | |
| 
 | |
| module_init(r3964_init);
 | |
| module_exit(r3964_exit);
 | |
| 
 | |
| /*************************************************************
 | |
|  * Protocol implementation routines
 | |
|  *************************************************************/
 | |
| 
 | |
| static void add_tx_queue(struct r3964_info *pInfo,
 | |
| 			 struct r3964_block_header *pHeader)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 
 | |
| 	pHeader->next = NULL;
 | |
| 
 | |
| 	if (pInfo->tx_last == NULL) {
 | |
| 		pInfo->tx_first = pInfo->tx_last = pHeader;
 | |
| 	} else {
 | |
| 		pInfo->tx_last->next = pHeader;
 | |
| 		pInfo->tx_last = pHeader;
 | |
| 	}
 | |
| 
 | |
| 	spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 
 | |
| 	TRACE_Q("add_tx_queue %p, length %d, tx_first = %p",
 | |
| 		pHeader, pHeader->length, pInfo->tx_first);
 | |
| }
 | |
| 
 | |
| static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code)
 | |
| {
 | |
| 	struct r3964_block_header *pHeader;
 | |
| 	unsigned long flags;
 | |
| #ifdef DEBUG_QUEUE
 | |
| 	struct r3964_block_header *pDump;
 | |
| #endif
 | |
| 
 | |
| 	pHeader = pInfo->tx_first;
 | |
| 
 | |
| 	if (pHeader == NULL)
 | |
| 		return;
 | |
| 
 | |
| #ifdef DEBUG_QUEUE
 | |
| 	printk("r3964: remove_from_tx_queue: %p, length %u - ",
 | |
| 		pHeader, pHeader->length);
 | |
| 	for (pDump = pHeader; pDump; pDump = pDump->next)
 | |
| 		printk("%p ", pDump);
 | |
| 	printk("\n");
 | |
| #endif
 | |
| 
 | |
| 	if (pHeader->owner) {
 | |
| 		if (error_code) {
 | |
| 			add_msg(pHeader->owner, R3964_MSG_ACK, 0,
 | |
| 				error_code, NULL);
 | |
| 		} else {
 | |
| 			add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length,
 | |
| 				error_code, NULL);
 | |
| 		}
 | |
| 		wake_up_interruptible(&pInfo->read_wait);
 | |
| 	}
 | |
| 
 | |
| 	spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 
 | |
| 	pInfo->tx_first = pHeader->next;
 | |
| 	if (pInfo->tx_first == NULL) {
 | |
| 		pInfo->tx_last = NULL;
 | |
| 	}
 | |
| 
 | |
| 	spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 
 | |
| 	kfree(pHeader);
 | |
| 	TRACE_M("remove_from_tx_queue - kfree %p", pHeader);
 | |
| 
 | |
| 	TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p",
 | |
| 		pInfo->tx_first, pInfo->tx_last);
 | |
| }
 | |
| 
 | |
| static void add_rx_queue(struct r3964_info *pInfo,
 | |
| 			 struct r3964_block_header *pHeader)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 
 | |
| 	pHeader->next = NULL;
 | |
| 
 | |
| 	if (pInfo->rx_last == NULL) {
 | |
| 		pInfo->rx_first = pInfo->rx_last = pHeader;
 | |
| 	} else {
 | |
| 		pInfo->rx_last->next = pHeader;
 | |
| 		pInfo->rx_last = pHeader;
 | |
| 	}
 | |
| 	pInfo->blocks_in_rx_queue++;
 | |
| 
 | |
| 	spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 
 | |
| 	TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d",
 | |
| 		pHeader, pHeader->length,
 | |
| 		pInfo->rx_first, pInfo->blocks_in_rx_queue);
 | |
| }
 | |
| 
 | |
| static void remove_from_rx_queue(struct r3964_info *pInfo,
 | |
| 				 struct r3964_block_header *pHeader)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 	struct r3964_block_header *pFind;
 | |
| 
 | |
| 	if (pHeader == NULL)
 | |
| 		return;
 | |
| 
 | |
| 	TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d",
 | |
| 		pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue);
 | |
| 	TRACE_Q("remove_from_rx_queue: %p, length %u",
 | |
| 		pHeader, pHeader->length);
 | |
| 
 | |
| 	spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 
 | |
| 	if (pInfo->rx_first == pHeader) {
 | |
| 		/* Remove the first block in the linked list: */
 | |
| 		pInfo->rx_first = pHeader->next;
 | |
| 
 | |
| 		if (pInfo->rx_first == NULL) {
 | |
| 			pInfo->rx_last = NULL;
 | |
| 		}
 | |
| 		pInfo->blocks_in_rx_queue--;
 | |
| 	} else {
 | |
| 		/* Find block to remove: */
 | |
| 		for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) {
 | |
| 			if (pFind->next == pHeader) {
 | |
| 				/* Got it. */
 | |
| 				pFind->next = pHeader->next;
 | |
| 				pInfo->blocks_in_rx_queue--;
 | |
| 				if (pFind->next == NULL) {
 | |
| 					/* Oh, removed the last one! */
 | |
| 					pInfo->rx_last = pFind;
 | |
| 				}
 | |
| 				break;
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 
 | |
| 	kfree(pHeader);
 | |
| 	TRACE_M("remove_from_rx_queue - kfree %p", pHeader);
 | |
| 
 | |
| 	TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d",
 | |
| 		pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue);
 | |
| }
 | |
| 
 | |
| static void put_char(struct r3964_info *pInfo, unsigned char ch)
 | |
| {
 | |
| 	struct tty_struct *tty = pInfo->tty;
 | |
| 	/* FIXME: put_char should not be called from an IRQ */
 | |
| 	tty_put_char(tty, ch);
 | |
| 	pInfo->bcc ^= ch;
 | |
| }
 | |
| 
 | |
| static void flush(struct r3964_info *pInfo)
 | |
| {
 | |
| 	struct tty_struct *tty = pInfo->tty;
 | |
| 
 | |
| 	if (tty == NULL || tty->ops->flush_chars == NULL)
 | |
| 		return;
 | |
| 	tty->ops->flush_chars(tty);
 | |
| }
 | |
| 
 | |
| static void trigger_transmit(struct r3964_info *pInfo)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 
 | |
| 	if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) {
 | |
| 		pInfo->state = R3964_TX_REQUEST;
 | |
| 		pInfo->nRetry = 0;
 | |
| 		pInfo->flags &= ~R3964_ERROR;
 | |
| 		mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ);
 | |
| 
 | |
| 		spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 
 | |
| 		TRACE_PS("trigger_transmit - sent STX");
 | |
| 
 | |
| 		put_char(pInfo, STX);
 | |
| 		flush(pInfo);
 | |
| 
 | |
| 		pInfo->bcc = 0;
 | |
| 	} else {
 | |
| 		spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void retry_transmit(struct r3964_info *pInfo)
 | |
| {
 | |
| 	if (pInfo->nRetry < R3964_MAX_RETRIES) {
 | |
| 		TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry);
 | |
| 		pInfo->bcc = 0;
 | |
| 		put_char(pInfo, STX);
 | |
| 		flush(pInfo);
 | |
| 		pInfo->state = R3964_TX_REQUEST;
 | |
| 		pInfo->nRetry++;
 | |
| 		mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ);
 | |
| 	} else {
 | |
| 		TRACE_PE("transmission failed after %d retries",
 | |
| 			 R3964_MAX_RETRIES);
 | |
| 
 | |
| 		remove_from_tx_queue(pInfo, R3964_TX_FAIL);
 | |
| 
 | |
| 		put_char(pInfo, NAK);
 | |
| 		flush(pInfo);
 | |
| 		pInfo->state = R3964_IDLE;
 | |
| 
 | |
| 		trigger_transmit(pInfo);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void transmit_block(struct r3964_info *pInfo)
 | |
| {
 | |
| 	struct tty_struct *tty = pInfo->tty;
 | |
| 	struct r3964_block_header *pBlock = pInfo->tx_first;
 | |
| 	int room = 0;
 | |
| 
 | |
| 	if (tty == NULL || pBlock == NULL) {
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	room = tty_write_room(tty);
 | |
| 
 | |
| 	TRACE_PS("transmit_block %p, room %d, length %d",
 | |
| 		 pBlock, room, pBlock->length);
 | |
| 
 | |
| 	while (pInfo->tx_position < pBlock->length) {
 | |
| 		if (room < 2)
 | |
| 			break;
 | |
| 
 | |
| 		if (pBlock->data[pInfo->tx_position] == DLE) {
 | |
| 			/* send additional DLE char: */
 | |
| 			put_char(pInfo, DLE);
 | |
| 		}
 | |
| 		put_char(pInfo, pBlock->data[pInfo->tx_position++]);
 | |
| 
 | |
| 		room--;
 | |
| 	}
 | |
| 
 | |
| 	if ((pInfo->tx_position == pBlock->length) && (room >= 3)) {
 | |
| 		put_char(pInfo, DLE);
 | |
| 		put_char(pInfo, ETX);
 | |
| 		if (pInfo->flags & R3964_BCC) {
 | |
| 			put_char(pInfo, pInfo->bcc);
 | |
| 		}
 | |
| 		pInfo->state = R3964_WAIT_FOR_TX_ACK;
 | |
| 		mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ);
 | |
| 	}
 | |
| 	flush(pInfo);
 | |
| }
 | |
| 
 | |
| static void on_receive_block(struct r3964_info *pInfo)
 | |
| {
 | |
| 	unsigned int length;
 | |
| 	struct r3964_client_info *pClient;
 | |
| 	struct r3964_block_header *pBlock;
 | |
| 
 | |
| 	length = pInfo->rx_position;
 | |
| 
 | |
| 	/* compare byte checksum characters: */
 | |
| 	if (pInfo->flags & R3964_BCC) {
 | |
| 		if (pInfo->bcc != pInfo->last_rx) {
 | |
| 			TRACE_PE("checksum error - got %x but expected %x",
 | |
| 				 pInfo->last_rx, pInfo->bcc);
 | |
| 			pInfo->flags |= R3964_CHECKSUM;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	/* check for errors (parity, overrun,...): */
 | |
| 	if (pInfo->flags & R3964_ERROR) {
 | |
| 		TRACE_PE("on_receive_block - transmission failed error %x",
 | |
| 			 pInfo->flags & R3964_ERROR);
 | |
| 
 | |
| 		put_char(pInfo, NAK);
 | |
| 		flush(pInfo);
 | |
| 		if (pInfo->nRetry < R3964_MAX_RETRIES) {
 | |
| 			pInfo->state = R3964_WAIT_FOR_RX_REPEAT;
 | |
| 			pInfo->nRetry++;
 | |
| 			mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC);
 | |
| 		} else {
 | |
| 			TRACE_PE("on_receive_block - failed after max retries");
 | |
| 			pInfo->state = R3964_IDLE;
 | |
| 		}
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	/* received block; submit DLE: */
 | |
| 	put_char(pInfo, DLE);
 | |
| 	flush(pInfo);
 | |
| 	del_timer_sync(&pInfo->tmr);
 | |
| 	TRACE_PS(" rx success: got %d chars", length);
 | |
| 
 | |
| 	/* prepare struct r3964_block_header: */
 | |
| 	pBlock = kmalloc(length + sizeof(struct r3964_block_header),
 | |
| 			GFP_KERNEL);
 | |
| 	TRACE_M("on_receive_block - kmalloc %p", pBlock);
 | |
| 
 | |
| 	if (pBlock == NULL)
 | |
| 		return;
 | |
| 
 | |
| 	pBlock->length = length;
 | |
| 	pBlock->data = ((unsigned char *)pBlock) +
 | |
| 			sizeof(struct r3964_block_header);
 | |
| 	pBlock->locks = 0;
 | |
| 	pBlock->next = NULL;
 | |
| 	pBlock->owner = NULL;
 | |
| 
 | |
| 	memcpy(pBlock->data, pInfo->rx_buf, length);
 | |
| 
 | |
| 	/* queue block into rx_queue: */
 | |
| 	add_rx_queue(pInfo, pBlock);
 | |
| 
 | |
| 	/* notify attached client processes: */
 | |
| 	for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) {
 | |
| 		if (pClient->sig_flags & R3964_SIG_DATA) {
 | |
| 			add_msg(pClient, R3964_MSG_DATA, length, R3964_OK,
 | |
| 				pBlock);
 | |
| 		}
 | |
| 	}
 | |
| 	wake_up_interruptible(&pInfo->read_wait);
 | |
| 
 | |
| 	pInfo->state = R3964_IDLE;
 | |
| 
 | |
| 	trigger_transmit(pInfo);
 | |
| }
 | |
| 
 | |
| static void receive_char(struct r3964_info *pInfo, const unsigned char c)
 | |
| {
 | |
| 	switch (pInfo->state) {
 | |
| 	case R3964_TX_REQUEST:
 | |
| 		if (c == DLE) {
 | |
| 			TRACE_PS("TX_REQUEST - got DLE");
 | |
| 
 | |
| 			pInfo->state = R3964_TRANSMITTING;
 | |
| 			pInfo->tx_position = 0;
 | |
| 
 | |
| 			transmit_block(pInfo);
 | |
| 		} else if (c == STX) {
 | |
| 			if (pInfo->nRetry == 0) {
 | |
| 				TRACE_PE("TX_REQUEST - init conflict");
 | |
| 				if (pInfo->priority == R3964_SLAVE) {
 | |
| 					goto start_receiving;
 | |
| 				}
 | |
| 			} else {
 | |
| 				TRACE_PE("TX_REQUEST - secondary init "
 | |
| 					"conflict!? Switching to SLAVE mode "
 | |
| 					"for next rx.");
 | |
| 				goto start_receiving;
 | |
| 			}
 | |
| 		} else {
 | |
| 			TRACE_PE("TX_REQUEST - char != DLE: %x", c);
 | |
| 			retry_transmit(pInfo);
 | |
| 		}
 | |
| 		break;
 | |
| 	case R3964_TRANSMITTING:
 | |
| 		if (c == NAK) {
 | |
| 			TRACE_PE("TRANSMITTING - got NAK");
 | |
| 			retry_transmit(pInfo);
 | |
| 		} else {
 | |
| 			TRACE_PE("TRANSMITTING - got invalid char");
 | |
| 
 | |
| 			pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY;
 | |
| 			mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ);
 | |
| 		}
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_TX_ACK:
 | |
| 		if (c == DLE) {
 | |
| 			TRACE_PS("WAIT_FOR_TX_ACK - got DLE");
 | |
| 			remove_from_tx_queue(pInfo, R3964_OK);
 | |
| 
 | |
| 			pInfo->state = R3964_IDLE;
 | |
| 			trigger_transmit(pInfo);
 | |
| 		} else {
 | |
| 			retry_transmit(pInfo);
 | |
| 		}
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_RX_REPEAT:
 | |
| 		/* FALLTROUGH */
 | |
| 	case R3964_IDLE:
 | |
| 		if (c == STX) {
 | |
| 			/* Prevent rx_queue from overflow: */
 | |
| 			if (pInfo->blocks_in_rx_queue >=
 | |
| 			    R3964_MAX_BLOCKS_IN_RX_QUEUE) {
 | |
| 				TRACE_PE("IDLE - got STX but no space in "
 | |
| 						"rx_queue!");
 | |
| 				pInfo->state = R3964_WAIT_FOR_RX_BUF;
 | |
| 				mod_timer(&pInfo->tmr,
 | |
| 					  jiffies + R3964_TO_NO_BUF);
 | |
| 				break;
 | |
| 			}
 | |
| start_receiving:
 | |
| 			/* Ok, start receiving: */
 | |
| 			TRACE_PS("IDLE - got STX");
 | |
| 			pInfo->rx_position = 0;
 | |
| 			pInfo->last_rx = 0;
 | |
| 			pInfo->flags &= ~R3964_ERROR;
 | |
| 			pInfo->state = R3964_RECEIVING;
 | |
| 			mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ);
 | |
| 			pInfo->nRetry = 0;
 | |
| 			put_char(pInfo, DLE);
 | |
| 			flush(pInfo);
 | |
| 			pInfo->bcc = 0;
 | |
| 		}
 | |
| 		break;
 | |
| 	case R3964_RECEIVING:
 | |
| 		if (pInfo->rx_position < RX_BUF_SIZE) {
 | |
| 			pInfo->bcc ^= c;
 | |
| 
 | |
| 			if (c == DLE) {
 | |
| 				if (pInfo->last_rx == DLE) {
 | |
| 					pInfo->last_rx = 0;
 | |
| 					goto char_to_buf;
 | |
| 				}
 | |
| 				pInfo->last_rx = DLE;
 | |
| 				break;
 | |
| 			} else if ((c == ETX) && (pInfo->last_rx == DLE)) {
 | |
| 				if (pInfo->flags & R3964_BCC) {
 | |
| 					pInfo->state = R3964_WAIT_FOR_BCC;
 | |
| 					mod_timer(&pInfo->tmr,
 | |
| 						  jiffies + R3964_TO_ZVZ);
 | |
| 				} else {
 | |
| 					on_receive_block(pInfo);
 | |
| 				}
 | |
| 			} else {
 | |
| 				pInfo->last_rx = c;
 | |
| char_to_buf:
 | |
| 				pInfo->rx_buf[pInfo->rx_position++] = c;
 | |
| 				mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ);
 | |
| 			}
 | |
| 		}
 | |
| 		/* else: overflow-msg? BUF_SIZE>MTU; should not happen? */
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_BCC:
 | |
| 		pInfo->last_rx = c;
 | |
| 		on_receive_block(pInfo);
 | |
| 		break;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void receive_error(struct r3964_info *pInfo, const char flag)
 | |
| {
 | |
| 	switch (flag) {
 | |
| 	case TTY_NORMAL:
 | |
| 		break;
 | |
| 	case TTY_BREAK:
 | |
| 		TRACE_PE("received break");
 | |
| 		pInfo->flags |= R3964_BREAK;
 | |
| 		break;
 | |
| 	case TTY_PARITY:
 | |
| 		TRACE_PE("parity error");
 | |
| 		pInfo->flags |= R3964_PARITY;
 | |
| 		break;
 | |
| 	case TTY_FRAME:
 | |
| 		TRACE_PE("frame error");
 | |
| 		pInfo->flags |= R3964_FRAME;
 | |
| 		break;
 | |
| 	case TTY_OVERRUN:
 | |
| 		TRACE_PE("frame overrun");
 | |
| 		pInfo->flags |= R3964_OVERRUN;
 | |
| 		break;
 | |
| 	default:
 | |
| 		TRACE_PE("receive_error - unknown flag %d", flag);
 | |
| 		pInfo->flags |= R3964_UNKNOWN;
 | |
| 		break;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void on_timeout(unsigned long priv)
 | |
| {
 | |
| 	struct r3964_info *pInfo = (void *)priv;
 | |
| 
 | |
| 	switch (pInfo->state) {
 | |
| 	case R3964_TX_REQUEST:
 | |
| 		TRACE_PE("TX_REQUEST - timeout");
 | |
| 		retry_transmit(pInfo);
 | |
| 		break;
 | |
| 	case R3964_WAIT_ZVZ_BEFORE_TX_RETRY:
 | |
| 		put_char(pInfo, NAK);
 | |
| 		flush(pInfo);
 | |
| 		retry_transmit(pInfo);
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_TX_ACK:
 | |
| 		TRACE_PE("WAIT_FOR_TX_ACK - timeout");
 | |
| 		retry_transmit(pInfo);
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_RX_BUF:
 | |
| 		TRACE_PE("WAIT_FOR_RX_BUF - timeout");
 | |
| 		put_char(pInfo, NAK);
 | |
| 		flush(pInfo);
 | |
| 		pInfo->state = R3964_IDLE;
 | |
| 		break;
 | |
| 	case R3964_RECEIVING:
 | |
| 		TRACE_PE("RECEIVING - timeout after %d chars",
 | |
| 			 pInfo->rx_position);
 | |
| 		put_char(pInfo, NAK);
 | |
| 		flush(pInfo);
 | |
| 		pInfo->state = R3964_IDLE;
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_RX_REPEAT:
 | |
| 		TRACE_PE("WAIT_FOR_RX_REPEAT - timeout");
 | |
| 		pInfo->state = R3964_IDLE;
 | |
| 		break;
 | |
| 	case R3964_WAIT_FOR_BCC:
 | |
| 		TRACE_PE("WAIT_FOR_BCC - timeout");
 | |
| 		put_char(pInfo, NAK);
 | |
| 		flush(pInfo);
 | |
| 		pInfo->state = R3964_IDLE;
 | |
| 		break;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static struct r3964_client_info *findClient(struct r3964_info *pInfo,
 | |
| 		struct pid *pid)
 | |
| {
 | |
| 	struct r3964_client_info *pClient;
 | |
| 
 | |
| 	for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) {
 | |
| 		if (pClient->pid == pid) {
 | |
| 			return pClient;
 | |
| 		}
 | |
| 	}
 | |
| 	return NULL;
 | |
| }
 | |
| 
 | |
| static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg)
 | |
| {
 | |
| 	struct r3964_client_info *pClient;
 | |
| 	struct r3964_client_info **ppClient;
 | |
| 	struct r3964_message *pMsg;
 | |
| 
 | |
| 	if ((arg & R3964_SIG_ALL) == 0) {
 | |
| 		/* Remove client from client list */
 | |
| 		for (ppClient = &pInfo->firstClient; *ppClient;
 | |
| 		     ppClient = &(*ppClient)->next) {
 | |
| 			pClient = *ppClient;
 | |
| 
 | |
| 			if (pClient->pid == pid) {
 | |
| 				TRACE_PS("removing client %d from client list",
 | |
| 					 pid_nr(pid));
 | |
| 				*ppClient = pClient->next;
 | |
| 				while (pClient->msg_count) {
 | |
| 					pMsg = remove_msg(pInfo, pClient);
 | |
| 					if (pMsg) {
 | |
| 						kfree(pMsg);
 | |
| 						TRACE_M("enable_signals - msg "
 | |
| 							"kfree %p", pMsg);
 | |
| 					}
 | |
| 				}
 | |
| 				put_pid(pClient->pid);
 | |
| 				kfree(pClient);
 | |
| 				TRACE_M("enable_signals - kfree %p", pClient);
 | |
| 				return 0;
 | |
| 			}
 | |
| 		}
 | |
| 		return -EINVAL;
 | |
| 	} else {
 | |
| 		pClient = findClient(pInfo, pid);
 | |
| 		if (pClient) {
 | |
| 			/* update signal options */
 | |
| 			pClient->sig_flags = arg;
 | |
| 		} else {
 | |
| 			/* add client to client list */
 | |
| 			pClient = kmalloc(sizeof(struct r3964_client_info),
 | |
| 					GFP_KERNEL);
 | |
| 			TRACE_M("enable_signals - kmalloc %p", pClient);
 | |
| 			if (pClient == NULL)
 | |
| 				return -ENOMEM;
 | |
| 
 | |
| 			TRACE_PS("add client %d to client list", pid_nr(pid));
 | |
| 			spin_lock_init(&pClient->lock);
 | |
| 			pClient->sig_flags = arg;
 | |
| 			pClient->pid = get_pid(pid);
 | |
| 			pClient->next = pInfo->firstClient;
 | |
| 			pClient->first_msg = NULL;
 | |
| 			pClient->last_msg = NULL;
 | |
| 			pClient->next_block_to_read = NULL;
 | |
| 			pClient->msg_count = 0;
 | |
| 			pInfo->firstClient = pClient;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int read_telegram(struct r3964_info *pInfo, struct pid *pid,
 | |
| 			 unsigned char __user * buf)
 | |
| {
 | |
| 	struct r3964_client_info *pClient;
 | |
| 	struct r3964_block_header *block;
 | |
| 
 | |
| 	if (!buf) {
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	pClient = findClient(pInfo, pid);
 | |
| 	if (pClient == NULL) {
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	block = pClient->next_block_to_read;
 | |
| 	if (!block) {
 | |
| 		return 0;
 | |
| 	} else {
 | |
| 		if (copy_to_user(buf, block->data, block->length))
 | |
| 			return -EFAULT;
 | |
| 
 | |
| 		remove_client_block(pInfo, pClient);
 | |
| 		return block->length;
 | |
| 	}
 | |
| 
 | |
| 	return -EINVAL;
 | |
| }
 | |
| 
 | |
| static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg,
 | |
| 		int error_code, struct r3964_block_header *pBlock)
 | |
| {
 | |
| 	struct r3964_message *pMsg;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) {
 | |
| queue_the_message:
 | |
| 
 | |
| 		pMsg = kmalloc(sizeof(struct r3964_message),
 | |
| 				error_code ? GFP_ATOMIC : GFP_KERNEL);
 | |
| 		TRACE_M("add_msg - kmalloc %p", pMsg);
 | |
| 		if (pMsg == NULL) {
 | |
| 			return;
 | |
| 		}
 | |
| 
 | |
| 		spin_lock_irqsave(&pClient->lock, flags);
 | |
| 
 | |
| 		pMsg->msg_id = msg_id;
 | |
| 		pMsg->arg = arg;
 | |
| 		pMsg->error_code = error_code;
 | |
| 		pMsg->block = pBlock;
 | |
| 		pMsg->next = NULL;
 | |
| 
 | |
| 		if (pClient->last_msg == NULL) {
 | |
| 			pClient->first_msg = pClient->last_msg = pMsg;
 | |
| 		} else {
 | |
| 			pClient->last_msg->next = pMsg;
 | |
| 			pClient->last_msg = pMsg;
 | |
| 		}
 | |
| 
 | |
| 		pClient->msg_count++;
 | |
| 
 | |
| 		if (pBlock != NULL) {
 | |
| 			pBlock->locks++;
 | |
| 		}
 | |
| 		spin_unlock_irqrestore(&pClient->lock, flags);
 | |
| 	} else {
 | |
| 		if ((pClient->last_msg->msg_id == R3964_MSG_ACK)
 | |
| 		    && (pClient->last_msg->error_code == R3964_OVERFLOW)) {
 | |
| 			pClient->last_msg->arg++;
 | |
| 			TRACE_PE("add_msg - inc prev OVERFLOW-msg");
 | |
| 		} else {
 | |
| 			msg_id = R3964_MSG_ACK;
 | |
| 			arg = 0;
 | |
| 			error_code = R3964_OVERFLOW;
 | |
| 			pBlock = NULL;
 | |
| 			TRACE_PE("add_msg - queue OVERFLOW-msg");
 | |
| 			goto queue_the_message;
 | |
| 		}
 | |
| 	}
 | |
| 	/* Send SIGIO signal to client process: */
 | |
| 	if (pClient->sig_flags & R3964_USE_SIGIO) {
 | |
| 		kill_pid(pClient->pid, SIGIO, 1);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static struct r3964_message *remove_msg(struct r3964_info *pInfo,
 | |
| 					struct r3964_client_info *pClient)
 | |
| {
 | |
| 	struct r3964_message *pMsg = NULL;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	if (pClient->first_msg) {
 | |
| 		spin_lock_irqsave(&pClient->lock, flags);
 | |
| 
 | |
| 		pMsg = pClient->first_msg;
 | |
| 		pClient->first_msg = pMsg->next;
 | |
| 		if (pClient->first_msg == NULL) {
 | |
| 			pClient->last_msg = NULL;
 | |
| 		}
 | |
| 
 | |
| 		pClient->msg_count--;
 | |
| 		if (pMsg->block) {
 | |
| 			remove_client_block(pInfo, pClient);
 | |
| 			pClient->next_block_to_read = pMsg->block;
 | |
| 		}
 | |
| 		spin_unlock_irqrestore(&pClient->lock, flags);
 | |
| 	}
 | |
| 	return pMsg;
 | |
| }
 | |
| 
 | |
| static void remove_client_block(struct r3964_info *pInfo,
 | |
| 				struct r3964_client_info *pClient)
 | |
| {
 | |
| 	struct r3964_block_header *block;
 | |
| 
 | |
| 	TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid));
 | |
| 
 | |
| 	block = pClient->next_block_to_read;
 | |
| 	if (block) {
 | |
| 		block->locks--;
 | |
| 		if (block->locks == 0) {
 | |
| 			remove_from_rx_queue(pInfo, block);
 | |
| 		}
 | |
| 	}
 | |
| 	pClient->next_block_to_read = NULL;
 | |
| }
 | |
| 
 | |
| /*************************************************************
 | |
|  * Line discipline routines
 | |
|  *************************************************************/
 | |
| 
 | |
| static int r3964_open(struct tty_struct *tty)
 | |
| {
 | |
| 	struct r3964_info *pInfo;
 | |
| 
 | |
| 	TRACE_L("open");
 | |
| 	TRACE_L("tty=%p, PID=%d, disc_data=%p",
 | |
| 		tty, current->pid, tty->disc_data);
 | |
| 
 | |
| 	pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL);
 | |
| 	TRACE_M("r3964_open - info kmalloc %p", pInfo);
 | |
| 
 | |
| 	if (!pInfo) {
 | |
| 		printk(KERN_ERR "r3964: failed to alloc info structure\n");
 | |
| 		return -ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL);
 | |
| 	TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf);
 | |
| 
 | |
| 	if (!pInfo->rx_buf) {
 | |
| 		printk(KERN_ERR "r3964: failed to alloc receive buffer\n");
 | |
| 		kfree(pInfo);
 | |
| 		TRACE_M("r3964_open - info kfree %p", pInfo);
 | |
| 		return -ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL);
 | |
| 	TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf);
 | |
| 
 | |
| 	if (!pInfo->tx_buf) {
 | |
| 		printk(KERN_ERR "r3964: failed to alloc transmit buffer\n");
 | |
| 		kfree(pInfo->rx_buf);
 | |
| 		TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf);
 | |
| 		kfree(pInfo);
 | |
| 		TRACE_M("r3964_open - info kfree %p", pInfo);
 | |
| 		return -ENOMEM;
 | |
| 	}
 | |
| 
 | |
| 	spin_lock_init(&pInfo->lock);
 | |
| 	pInfo->tty = tty;
 | |
| 	init_waitqueue_head(&pInfo->read_wait);
 | |
| 	pInfo->priority = R3964_MASTER;
 | |
| 	pInfo->rx_first = pInfo->rx_last = NULL;
 | |
| 	pInfo->tx_first = pInfo->tx_last = NULL;
 | |
| 	pInfo->rx_position = 0;
 | |
| 	pInfo->tx_position = 0;
 | |
| 	pInfo->last_rx = 0;
 | |
| 	pInfo->blocks_in_rx_queue = 0;
 | |
| 	pInfo->firstClient = NULL;
 | |
| 	pInfo->state = R3964_IDLE;
 | |
| 	pInfo->flags = R3964_DEBUG;
 | |
| 	pInfo->nRetry = 0;
 | |
| 
 | |
| 	tty->disc_data = pInfo;
 | |
| 	tty->receive_room = 65536;
 | |
| 
 | |
| 	setup_timer(&pInfo->tmr, on_timeout, (unsigned long)pInfo);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static void r3964_close(struct tty_struct *tty)
 | |
| {
 | |
| 	struct r3964_info *pInfo = tty->disc_data;
 | |
| 	struct r3964_client_info *pClient, *pNext;
 | |
| 	struct r3964_message *pMsg;
 | |
| 	struct r3964_block_header *pHeader, *pNextHeader;
 | |
| 	unsigned long flags;
 | |
| 
 | |
| 	TRACE_L("close");
 | |
| 
 | |
| 	/*
 | |
| 	 * Make sure that our task queue isn't activated.  If it
 | |
| 	 * is, take it out of the linked list.
 | |
| 	 */
 | |
| 	del_timer_sync(&pInfo->tmr);
 | |
| 
 | |
| 	/* Remove client-structs and message queues: */
 | |
| 	pClient = pInfo->firstClient;
 | |
| 	while (pClient) {
 | |
| 		pNext = pClient->next;
 | |
| 		while (pClient->msg_count) {
 | |
| 			pMsg = remove_msg(pInfo, pClient);
 | |
| 			if (pMsg) {
 | |
| 				kfree(pMsg);
 | |
| 				TRACE_M("r3964_close - msg kfree %p", pMsg);
 | |
| 			}
 | |
| 		}
 | |
| 		put_pid(pClient->pid);
 | |
| 		kfree(pClient);
 | |
| 		TRACE_M("r3964_close - client kfree %p", pClient);
 | |
| 		pClient = pNext;
 | |
| 	}
 | |
| 	/* Remove jobs from tx_queue: */
 | |
| 	spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 	pHeader = pInfo->tx_first;
 | |
| 	pInfo->tx_first = pInfo->tx_last = NULL;
 | |
| 	spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 
 | |
| 	while (pHeader) {
 | |
| 		pNextHeader = pHeader->next;
 | |
| 		kfree(pHeader);
 | |
| 		pHeader = pNextHeader;
 | |
| 	}
 | |
| 
 | |
| 	/* Free buffers: */
 | |
| 	wake_up_interruptible(&pInfo->read_wait);
 | |
| 	kfree(pInfo->rx_buf);
 | |
| 	TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf);
 | |
| 	kfree(pInfo->tx_buf);
 | |
| 	TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf);
 | |
| 	kfree(pInfo);
 | |
| 	TRACE_M("r3964_close - info kfree %p", pInfo);
 | |
| }
 | |
| 
 | |
| static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
 | |
| 			  unsigned char __user * buf, size_t nr)
 | |
| {
 | |
| 	struct r3964_info *pInfo = tty->disc_data;
 | |
| 	struct r3964_client_info *pClient;
 | |
| 	struct r3964_message *pMsg;
 | |
| 	struct r3964_client_message theMsg;
 | |
| 	int count;
 | |
| 
 | |
| 	TRACE_L("read()");
 | |
| 
 | |
| 	lock_kernel();
 | |
| 
 | |
| 	pClient = findClient(pInfo, task_pid(current));
 | |
| 	if (pClient) {
 | |
| 		pMsg = remove_msg(pInfo, pClient);
 | |
| 		if (pMsg == NULL) {
 | |
| 			/* no messages available. */
 | |
| 			if (file->f_flags & O_NONBLOCK) {
 | |
| 				unlock_kernel();
 | |
| 				return -EAGAIN;
 | |
| 			}
 | |
| 			/* block until there is a message: */
 | |
| 			wait_event_interruptible(pInfo->read_wait,
 | |
| 					(pMsg = remove_msg(pInfo, pClient)));
 | |
| 		}
 | |
| 
 | |
| 		/* If we still haven't got a message, we must have been signalled */
 | |
| 
 | |
| 		if (!pMsg) {
 | |
| 			unlock_kernel();
 | |
| 			return -EINTR;
 | |
| 		}
 | |
| 
 | |
| 		/* deliver msg to client process: */
 | |
| 		theMsg.msg_id = pMsg->msg_id;
 | |
| 		theMsg.arg = pMsg->arg;
 | |
| 		theMsg.error_code = pMsg->error_code;
 | |
| 		count = sizeof(struct r3964_client_message);
 | |
| 
 | |
| 		kfree(pMsg);
 | |
| 		TRACE_M("r3964_read - msg kfree %p", pMsg);
 | |
| 
 | |
| 		if (copy_to_user(buf, &theMsg, count)) {
 | |
| 			unlock_kernel();
 | |
| 			return -EFAULT;
 | |
| 		}
 | |
| 
 | |
| 		TRACE_PS("read - return %d", count);
 | |
| 		return count;
 | |
| 	}
 | |
| 	unlock_kernel();
 | |
| 	return -EPERM;
 | |
| }
 | |
| 
 | |
| static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
 | |
| 			   const unsigned char *data, size_t count)
 | |
| {
 | |
| 	struct r3964_info *pInfo = tty->disc_data;
 | |
| 	struct r3964_block_header *pHeader;
 | |
| 	struct r3964_client_info *pClient;
 | |
| 	unsigned char *new_data;
 | |
| 
 | |
| 	TRACE_L("write request, %d characters", count);
 | |
| /* 
 | |
|  * Verify the pointers 
 | |
|  */
 | |
| 
 | |
| 	if (!pInfo)
 | |
| 		return -EIO;
 | |
| 
 | |
| /*
 | |
|  * Ensure that the caller does not wish to send too much.
 | |
|  */
 | |
| 	if (count > R3964_MTU) {
 | |
| 		if (pInfo->flags & R3964_DEBUG) {
 | |
| 			TRACE_L(KERN_WARNING "r3964_write: truncating user "
 | |
| 				"packet from %u to mtu %d", count, R3964_MTU);
 | |
| 		}
 | |
| 		count = R3964_MTU;
 | |
| 	}
 | |
| /*
 | |
|  * Allocate a buffer for the data and copy it from the buffer with header prepended
 | |
|  */
 | |
| 	new_data = kmalloc(count + sizeof(struct r3964_block_header),
 | |
| 			GFP_KERNEL);
 | |
| 	TRACE_M("r3964_write - kmalloc %p", new_data);
 | |
| 	if (new_data == NULL) {
 | |
| 		if (pInfo->flags & R3964_DEBUG) {
 | |
| 			printk(KERN_ERR "r3964_write: no memory\n");
 | |
| 		}
 | |
| 		return -ENOSPC;
 | |
| 	}
 | |
| 
 | |
| 	pHeader = (struct r3964_block_header *)new_data;
 | |
| 	pHeader->data = new_data + sizeof(struct r3964_block_header);
 | |
| 	pHeader->length = count;
 | |
| 	pHeader->locks = 0;
 | |
| 	pHeader->owner = NULL;
 | |
| 
 | |
| 	lock_kernel();
 | |
| 
 | |
| 	pClient = findClient(pInfo, task_pid(current));
 | |
| 	if (pClient) {
 | |
| 		pHeader->owner = pClient;
 | |
| 	}
 | |
| 
 | |
| 	memcpy(pHeader->data, data, count);	/* We already verified this */
 | |
| 
 | |
| 	if (pInfo->flags & R3964_DEBUG) {
 | |
| 		dump_block(pHeader->data, count);
 | |
| 	}
 | |
| 
 | |
| /*
 | |
|  * Add buffer to transmit-queue:
 | |
|  */
 | |
| 	add_tx_queue(pInfo, pHeader);
 | |
| 	trigger_transmit(pInfo);
 | |
| 
 | |
| 	unlock_kernel();
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int r3964_ioctl(struct tty_struct *tty, struct file *file,
 | |
| 		unsigned int cmd, unsigned long arg)
 | |
| {
 | |
| 	struct r3964_info *pInfo = tty->disc_data;
 | |
| 	if (pInfo == NULL)
 | |
| 		return -EINVAL;
 | |
| 	switch (cmd) {
 | |
| 	case R3964_ENABLE_SIGNALS:
 | |
| 		return enable_signals(pInfo, task_pid(current), arg);
 | |
| 	case R3964_SETPRIORITY:
 | |
| 		if (arg < R3964_MASTER || arg > R3964_SLAVE)
 | |
| 			return -EINVAL;
 | |
| 		pInfo->priority = arg & 0xff;
 | |
| 		return 0;
 | |
| 	case R3964_USE_BCC:
 | |
| 		if (arg)
 | |
| 			pInfo->flags |= R3964_BCC;
 | |
| 		else
 | |
| 			pInfo->flags &= ~R3964_BCC;
 | |
| 		return 0;
 | |
| 	case R3964_READ_TELEGRAM:
 | |
| 		return read_telegram(pInfo, task_pid(current),
 | |
| 				(unsigned char __user *)arg);
 | |
| 	default:
 | |
| 		return -ENOIOCTLCMD;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old)
 | |
| {
 | |
| 	TRACE_L("set_termios");
 | |
| }
 | |
| 
 | |
| /* Called without the kernel lock held - fine */
 | |
| static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
 | |
| 			struct poll_table_struct *wait)
 | |
| {
 | |
| 	struct r3964_info *pInfo = tty->disc_data;
 | |
| 	struct r3964_client_info *pClient;
 | |
| 	struct r3964_message *pMsg = NULL;
 | |
| 	unsigned long flags;
 | |
| 	int result = POLLOUT;
 | |
| 
 | |
| 	TRACE_L("POLL");
 | |
| 
 | |
| 	pClient = findClient(pInfo, task_pid(current));
 | |
| 	if (pClient) {
 | |
| 		poll_wait(file, &pInfo->read_wait, wait);
 | |
| 		spin_lock_irqsave(&pInfo->lock, flags);
 | |
| 		pMsg = pClient->first_msg;
 | |
| 		spin_unlock_irqrestore(&pInfo->lock, flags);
 | |
| 		if (pMsg)
 | |
| 			result |= POLLIN | POLLRDNORM;
 | |
| 	} else {
 | |
| 		result = -EINVAL;
 | |
| 	}
 | |
| 	return result;
 | |
| }
 | |
| 
 | |
| static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
 | |
| 			char *fp, int count)
 | |
| {
 | |
| 	struct r3964_info *pInfo = tty->disc_data;
 | |
| 	const unsigned char *p;
 | |
| 	char *f, flags = 0;
 | |
| 	int i;
 | |
| 
 | |
| 	for (i = count, p = cp, f = fp; i; i--, p++) {
 | |
| 		if (f)
 | |
| 			flags = *f++;
 | |
| 		if (flags == TTY_NORMAL) {
 | |
| 			receive_char(pInfo, *p);
 | |
| 		} else {
 | |
| 			receive_error(pInfo, flags);
 | |
| 		}
 | |
| 
 | |
| 	}
 | |
| }
 | |
| 
 | |
| MODULE_LICENSE("GPL");
 | |
| MODULE_ALIAS_LDISC(N_R3964);
 |