patch-2.3.16 linux/drivers/char/n_r3964.c
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- Lines: 1490
- Date:
Mon Aug 30 18:05:19 1999
- Orig file:
v2.3.15/linux/drivers/char/n_r3964.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.3.15/linux/drivers/char/n_r3964.c linux/drivers/char/n_r3964.c
@@ -0,0 +1,1489 @@
+/* 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 Public License, incorporated herein by reference.
+ *
+ * Author:
+ * L. Haag
+ *
+ * $Log: r3964.c,v $
+ * 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
+ *
+ *
+ */
+#define R3964_VERSION "1.7"
+
+#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/malloc.h>
+#include <linux/tty.h>
+#include <linux/errno.h>
+#include <linux/sched.h> /* to get the struct task_struct */
+#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 successfull 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...) /**/
+#endif
+
+#ifdef DEBUG_PROTO_S
+#define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args);
+#else
+#define TRACE_PS(fmt, arg...) /**/
+#endif
+
+#ifdef DEBUG_PROTO_E
+#define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args);
+#else
+#define TRACE_PE(fmt, arg...) /**/
+#endif
+
+#ifdef DEBUG_LDISC
+#define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args);
+#else
+#define TRACE_L(fmt, arg...) /**/
+#endif
+
+#ifdef DEBUG_QUEUE
+#define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args);
+#else
+#define TRACE_Q(fmt, arg...) /**/
+#endif
+
+void cleanup_module(void);
+
+static void on_timer_1(void*);
+static void on_timer_2(void*);
+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(struct r3964_info *pInfo);
+static int enable_signals(struct r3964_info *pInfo, pid_t pid, int arg);
+static int read_telegram(struct r3964_info *pInfo, pid_t pid, unsigned char *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 int r3964_read(struct tty_struct *tty, struct file *file,
+ unsigned char *buf, unsigned int nr);
+static int r3964_write(struct tty_struct * tty, struct file * file,
+ const unsigned char * buf, unsigned int 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 termios * 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 int r3964_receive_room(struct tty_struct *tty);
+
+static struct tty_ldisc tty_ldisc_N_R3964 = {
+ TTY_LDISC_MAGIC, /* magic */
+ "R3964", /* name */
+ 0, /* num */
+ 0, /* flags */
+ r3964_open, /* open */
+ r3964_close, /* close */
+ 0, /* flush_buffer */
+ 0, /* chars_in_buffer */
+ r3964_read, /* read */
+ r3964_write, /* write */
+ r3964_ioctl, /* ioctl */
+ r3964_set_termios, /* set_termios */
+ r3964_poll, /* poll */
+ r3964_receive_buf, /* receive_buf */
+ r3964_receive_room, /* receive_room */
+ 0 /* write_wakeup */
+};
+
+
+
+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
+ *************************************************************/
+
+#ifdef MODULE
+
+#define r3964_init init_module
+
+void cleanup_module(void)
+{
+ int status;
+
+ TRACE_M ("cleanup_module()");
+
+ status=tty_register_ldisc(N_R3964, NULL);
+
+ if(status!=0)
+ {
+ printk(KERN_ERR "r3964: error unregistering linediscipline: %d\n", status);
+ }
+ else
+ {
+ TRACE_L("linediscipline successfully unregistered");
+ }
+
+}
+
+
+#endif /* MODULE */
+
+__initfunc(static int r3964_init(void))
+{
+ int status;
+
+ printk ("r3964: Philips r3964 Driver V%s\n", R3964_VERSION);
+
+ /*
+ * 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=%x", (int)tty_ldisc_N_R3964.open);
+ TRACE_L("tty_ldisc_N_R3964 = %x", (int)&tty_ldisc_N_R3964);
+ }
+ else
+ {
+ printk (KERN_ERR "r3964: error registering line discipline: %d\n", status);
+ }
+ return status;
+}
+
+#ifndef MODULE
+__initcall (r3964_init);
+#endif
+
+/*************************************************************
+ * Protocol implementation routines
+ *************************************************************/
+
+static void on_timer_1(void *arg)
+{
+ struct r3964_info *pInfo = (struct r3964_info *)arg;
+
+ if(pInfo->count_down)
+ {
+ if(!--pInfo->count_down)
+ {
+ on_timeout(pInfo);
+ }
+ }
+ queue_task(&pInfo->bh_2, &tq_timer);
+}
+
+static void on_timer_2(void *arg)
+{
+ struct r3964_info *pInfo = (struct r3964_info *)arg;
+
+ if(pInfo->count_down)
+ {
+ if(!--pInfo->count_down)
+ {
+ on_timeout(pInfo);
+ }
+ }
+ queue_task(&pInfo->bh_1, &tq_timer);
+}
+
+static void add_tx_queue(struct r3964_info *pInfo, struct r3964_block_header *pHeader)
+{
+ unsigned long flags;
+
+ save_flags(flags);
+ cli();
+
+ 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;
+ }
+
+ restore_flags(flags);
+
+ TRACE_Q("add_tx_queue %x, length %d, tx_first = %x",
+ (int)pHeader, pHeader->length, (int)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: %x, length %d - ",
+ (int)pHeader, (int)pHeader->length );
+ for(pDump=pHeader;pDump;pDump=pDump->next)
+ printk("%x ", (int)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);
+ }
+
+ save_flags(flags);
+ cli();
+
+ pInfo->tx_first = pHeader->next;
+ if(pInfo->tx_first==NULL)
+ {
+ pInfo->tx_last = NULL;
+ }
+
+ restore_flags(flags);
+
+ kfree(pHeader);
+ TRACE_M("remove_from_tx_queue - kfree %x",(int)pHeader);
+
+ TRACE_Q("remove_from_tx_queue: tx_first = %x, tx_last = %x",
+ (int)pInfo->tx_first, (int)pInfo->tx_last );
+}
+
+static void add_rx_queue(struct r3964_info *pInfo, struct r3964_block_header *pHeader)
+{
+ unsigned long flags;
+
+ save_flags(flags);
+ cli();
+
+ 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++;
+
+ restore_flags(flags);
+
+ TRACE_Q("add_rx_queue: %x, length = %d, rx_first = %x, count = %d",
+ (int)pHeader, pHeader->length,
+ (int)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 = %x, rx_last = %x, count = %d",
+ (int)pInfo->rx_first, (int)pInfo->rx_last, pInfo->blocks_in_rx_queue );
+ TRACE_Q("remove_from_rx_queue: %x, length %d",
+ (int)pHeader, (int)pHeader->length );
+
+ save_flags(flags);
+ cli();
+
+ 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;
+ }
+ }
+ }
+
+ restore_flags(flags);
+
+ kfree(pHeader);
+ TRACE_M("remove_from_rx_queue - kfree %x",(int)pHeader);
+
+ TRACE_Q("remove_from_rx_queue: rx_first = %x, rx_last = %x, count = %d",
+ (int)pInfo->rx_first, (int)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;
+
+ if(tty==NULL)
+ return;
+
+ if(tty->driver.put_char)
+ {
+ tty->driver.put_char(tty, ch);
+ }
+ pInfo->bcc ^= ch;
+}
+
+static void flush(struct r3964_info *pInfo)
+{
+ struct tty_struct *tty = pInfo->tty;
+
+ if(tty==NULL)
+ return;
+
+ if(tty->driver.flush_chars)
+ {
+ tty->driver.flush_chars(tty);
+ }
+}
+
+static void trigger_transmit(struct r3964_info *pInfo)
+{
+ unsigned long flags;
+
+
+ save_flags(flags);
+ cli();
+
+ if((pInfo->state == R3964_IDLE) && (pInfo->tx_first!=NULL))
+ {
+ pInfo->state = R3964_TX_REQUEST;
+ pInfo->count_down = R3964_TO_QVZ;
+ pInfo->nRetry=0;
+ pInfo->flags &= ~R3964_ERROR;
+
+ restore_flags(flags);
+
+ TRACE_PS("trigger_transmit - sent STX");
+
+ put_char(pInfo, STX);
+ flush(pInfo);
+
+ pInfo->bcc = 0;
+ }
+ else
+ {
+ restore_flags(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->count_down = R3964_TO_QVZ;
+ pInfo->nRetry++;
+ }
+ 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;
+ }
+
+ if(tty->driver.write_room)
+ room=tty->driver.write_room(tty);
+
+ TRACE_PS("transmit_block %x, room %d, length %d",
+ (int)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;
+ pInfo->count_down = 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->count_down = R3964_TO_RX_PANIC;
+ pInfo->nRetry++;
+ }
+ 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);
+ pInfo->count_down=0;
+ 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 %x",(int)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 illegal char");
+
+ pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY;
+ pInfo->count_down = 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;
+ pInfo->count_down = 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;
+ pInfo->count_down = 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;
+ pInfo->count_down = R3964_TO_ZVZ;
+ }
+ else
+ {
+ on_receive_block(pInfo);
+ }
+ }
+ else
+ {
+ pInfo->last_rx = c;
+char_to_buf:
+ pInfo->rx_buf[pInfo->rx_position++] = c;
+ pInfo->count_down = 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(struct r3964_info *pInfo)
+{
+ 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, pid_t 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, pid_t 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);
+ *ppClient = pClient->next;
+ while(pClient->msg_count)
+ {
+ pMsg=remove_msg(pInfo, pClient);
+ if(pMsg)
+ {
+ kfree(pMsg);
+ TRACE_M("enable_signals - msg kfree %x",(int)pMsg);
+ }
+ }
+ kfree(pClient);
+ TRACE_M("enable_signals - kfree %x",(int)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 %x",(int)pClient);
+ if(pClient==NULL)
+ return -ENOMEM;
+
+ TRACE_PS("add client %d to client list", pid);
+ pClient->sig_flags=arg;
+ pClient->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, pid_t pid, unsigned char *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:
+
+ save_flags(flags);
+ cli();
+
+ pMsg = kmalloc(sizeof(struct r3964_message), GFP_KERNEL);
+ TRACE_M("add_msg - kmalloc %x",(int)pMsg);
+ if(pMsg==NULL)
+ return;
+
+ 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++;
+ }
+ restore_flags(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_proc(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)
+ {
+ save_flags(flags);
+ cli();
+
+ 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;
+ }
+ restore_flags(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", 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;
+
+ MOD_INC_USE_COUNT;
+
+ TRACE_L("open");
+ TRACE_L("tty=%x, PID=%d, disc_data=%x",
+ (int)tty, current->pid, (int)tty->disc_data);
+
+ pInfo=kmalloc(sizeof(struct r3964_info), GFP_KERNEL);
+ TRACE_M("r3964_open - info kmalloc %x",(int)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 %x",(int)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 %x",(int)pInfo);
+ return -ENOMEM;
+ }
+
+ pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL);
+ TRACE_M("r3964_open - tx_buf kmalloc %x",(int)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 %x",(int)pInfo->rx_buf);
+ kfree(pInfo);
+ TRACE_M("r3964_open - info kfree %x",(int)pInfo);
+ return -ENOMEM;
+ }
+
+ 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->count_down = 0;
+ pInfo->nRetry = 0;
+
+ tty->disc_data = pInfo;
+
+ /*
+ * Add 'on_timer' to timer task queue
+ * (will be called from timer bh)
+ */
+ pInfo->bh_1.next = NULL;
+ pInfo->bh_1.sync = 0;
+ pInfo->bh_1.routine = &on_timer_1;
+ pInfo->bh_1.data = pInfo;
+
+ pInfo->bh_2.next = NULL;
+ pInfo->bh_2.sync = 0;
+ pInfo->bh_2.routine = &on_timer_2;
+ pInfo->bh_2.data = pInfo;
+
+ queue_task(&pInfo->bh_1, &tq_timer);
+
+ return 0;
+}
+
+static void r3964_close(struct tty_struct *tty)
+{
+ struct tq_struct *tq, *prev;
+ struct r3964_info *pInfo=(struct r3964_info*)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.
+ */
+ save_flags(flags);
+ cli();
+
+ for (tq=tq_timer, prev=0; tq; prev=tq, tq=tq->next) {
+ if ((tq == &pInfo->bh_1) || (tq==&pInfo->bh_2)) {
+ if (prev)
+ prev->next = tq->next;
+ else
+ tq_timer = tq->next;
+ break;
+ }
+ }
+ restore_flags(flags);
+
+ /* 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 %x",(int)pMsg);
+ }
+ }
+ kfree(pClient);
+ TRACE_M("r3964_close - client kfree %x",(int)pClient);
+ pClient=pNext;
+ }
+ /* Remove jobs from tx_queue: */
+ save_flags(flags);
+ cli();
+ pHeader=pInfo->tx_first;
+ pInfo->tx_first=pInfo->tx_last=NULL;
+ restore_flags(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 %x",(int)pInfo->rx_buf);
+ kfree(pInfo->tx_buf);
+ TRACE_M("r3964_close - tx_buf kfree %x",(int)pInfo->tx_buf);
+ kfree(pInfo);
+ TRACE_M("r3964_close - info kfree %x",(int)pInfo);
+
+ MOD_DEC_USE_COUNT;
+}
+
+static int r3964_read(struct tty_struct *tty, struct file *file,
+ unsigned char *buf, unsigned int nr)
+{
+ struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data;
+ struct r3964_client_info *pClient;
+ struct r3964_message *pMsg;
+ struct r3964_client_message theMsg;
+ DECLARE_WAITQUEUE (wait, current);
+
+ int pid = current->pid;
+ int count;
+
+ TRACE_L("read()");
+
+ pClient=findClient(pInfo, pid);
+ if(pClient)
+ {
+ pMsg = remove_msg(pInfo, pClient);
+ if(pMsg==NULL)
+ {
+ /* no messages available. */
+ if (file->f_flags & O_NONBLOCK)
+ {
+ return -EAGAIN;
+ }
+ /* block until there is a message: */
+ add_wait_queue(&pInfo->read_wait, &wait);
+repeat:
+ pMsg = remove_msg(pInfo, pClient);
+ current->state = TASK_INTERRUPTIBLE;
+ if (!pMsg && !signal_pending(current))
+ {
+ schedule();
+ goto repeat;
+ }
+ current->state = TASK_RUNNING;
+ remove_wait_queue(&pInfo->read_wait, &wait);
+ }
+
+ /* If we still haven't got a message, we must have been signalled */
+
+ if (!pMsg) 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 %x",(int)pMsg);
+
+ if (copy_to_user(buf,&theMsg, count))
+ return -EFAULT;
+
+ TRACE_PS("read - return %d", count);
+ return count;
+ }
+ return -EPERM;
+}
+
+static int r3964_write(struct tty_struct * tty, struct file * file,
+ const unsigned char *data, unsigned int count)
+{
+ struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data;
+ struct r3964_block_header *pHeader;
+ struct r3964_client_info *pClient;
+ unsigned char *new_data;
+ int status;
+ int pid;
+
+ TRACE_L("write request, %d characters", count);
+/*
+ * Verify the pointers
+ */
+
+ if(!pInfo)
+ return -EIO;
+
+ status = verify_area (VERIFY_READ, data, count);
+ if (status != 0)
+ {
+ return status;
+ }
+
+/*
+ * 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 fetch it from the user space.
+ */
+ new_data = kmalloc (count+sizeof(struct r3964_block_header), GFP_KERNEL);
+ TRACE_M("r3964_write - kmalloc %x",(int)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;
+
+ pid=current->pid;
+
+ pClient=findClient(pInfo, pid);
+ if(pClient)
+ {
+ pHeader->owner = pClient;
+ }
+
+ copy_from_user (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);
+
+ return 0;
+}
+
+static int r3964_ioctl(struct tty_struct * tty, struct file * file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data;
+ if(pInfo==NULL)
+ return -EINVAL;
+ switch(cmd)
+ {
+ case R3964_ENABLE_SIGNALS:
+ return enable_signals(pInfo, current->pid, 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, current->pid, (unsigned char *)arg);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static void r3964_set_termios(struct tty_struct *tty, struct termios * old)
+{
+ TRACE_L("set_termios");
+}
+
+static unsigned int r3964_poll(struct tty_struct * tty, struct file * file,
+ struct poll_table_struct *wait)
+{
+ struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data;
+ int pid=current->pid;
+ struct r3964_client_info *pClient;
+ struct r3964_message *pMsg=NULL;
+ unsigned int flags;
+ int result = POLLOUT;
+
+ TRACE_L("POLL");
+
+ pClient=findClient(pInfo,pid);
+ if(pClient)
+ {
+ poll_wait(file, &pInfo->read_wait, wait);
+ save_flags(flags);
+ cli();
+ pMsg=pClient->first_msg;
+ restore_flags(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=(struct r3964_info*)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);
+ }
+
+ }
+}
+
+static int r3964_receive_room(struct tty_struct *tty)
+{
+ TRACE_L("receive_room");
+ return -1;
+}
+
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)