sx.c

linux 内核源代码

	int retval, line;
	unsigned long flags;

	func_enter();

	if (!sx_initialized) {
		return -EIO;
	}

	line = tty->index;
	sx_dprintk(SX_DEBUG_OPEN, "%d: opening line %d. tty=%p ctty=%p, "
			"np=%d)\n", task_pid_nr(current), line, tty,
			current->signal->tty, sx_nports);

	if ((line < 0) || (line >= SX_NPORTS) || (line >= sx_nports))
		return -ENODEV;

	port = &sx_ports[line];
	port->c_dcd = 0; /* Make sure that the first interrupt doesn't detect a
			    1 -> 0 transition. */

	sx_dprintk(SX_DEBUG_OPEN, "port = %p c_dcd = %d\n", port, port->c_dcd);

	spin_lock_irqsave(&port->gs.driver_lock, flags);

	tty->driver_data = port;
	port->gs.tty = tty;
	port->gs.count++;
	spin_unlock_irqrestore(&port->gs.driver_lock, flags);

	sx_dprintk(SX_DEBUG_OPEN, "starting port\n");

	/*
	 * Start up serial port
	 */
	retval = gs_init_port(&port->gs);
	sx_dprintk(SX_DEBUG_OPEN, "done gs_init\n");
	if (retval) {
		port->gs.count--;
		return retval;
	}

	port->gs.flags |= GS_ACTIVE;
	if (port->gs.count <= 1)
		sx_setsignals(port, 1, 1);

#if 0
	if (sx_debug & SX_DEBUG_OPEN)
		my_hd(port, sizeof(*port));
#else
	if (sx_debug & SX_DEBUG_OPEN)
		my_hd_io(port->board->base + port->ch_base, sizeof(*port));
#endif

	if (port->gs.count <= 1) {
		if (sx_send_command(port, HS_LOPEN, -1, HS_IDLE_OPEN) != 1) {
			printk(KERN_ERR "sx: Card didn't respond to LOPEN "
					"command.\n");
			spin_lock_irqsave(&port->gs.driver_lock, flags);
			port->gs.count--;
			spin_unlock_irqrestore(&port->gs.driver_lock, flags);
			return -EIO;
		}
	}

	retval = gs_block_til_ready(port, filp);
	sx_dprintk(SX_DEBUG_OPEN, "Block til ready returned %d. Count=%d\n",
			retval, port->gs.count);

	if (retval) {
/*
 * Don't lower gs.count here because sx_close() will be called later
 */

		return retval;
	}
	/* tty->low_latency = 1; */

	port->c_dcd = sx_get_CD(port);
	sx_dprintk(SX_DEBUG_OPEN, "at open: cd=%d\n", port->c_dcd);

	func_exit();
	return 0;

}

static void sx_close(void *ptr)
{
	struct sx_port *port = ptr;
	/* Give the port 5 seconds to close down. */
	int to = 5 * HZ;

	func_enter();

	sx_setsignals(port, 0, 0);
	sx_reconfigure_port(port);
	sx_send_command(port, HS_CLOSE, 0, 0);

	while (to-- && (sx_read_channel_byte(port, hi_hstat) != HS_IDLE_CLOSED))
		if (msleep_interruptible(10))
			break;
	if (sx_read_channel_byte(port, hi_hstat) != HS_IDLE_CLOSED) {
		if (sx_send_command(port, HS_FORCE_CLOSED, -1, HS_IDLE_CLOSED)
				!= 1) {
			printk(KERN_ERR "sx: sent the force_close command, but "
					"card didn't react\n");
		} else
			sx_dprintk(SX_DEBUG_CLOSE, "sent the force_close "
					"command.\n");
	}

	sx_dprintk(SX_DEBUG_CLOSE, "waited %d jiffies for close. count=%d\n",
			5 * HZ - to - 1, port->gs.count);

	if (port->gs.count) {
		sx_dprintk(SX_DEBUG_CLOSE, "WARNING port count:%d\n",
				port->gs.count);
		/*printk("%s SETTING port count to zero: %p count: %d\n",
				__FUNCTION__, port, port->gs.count);
		port->gs.count = 0;*/
	}

	func_exit();
}

/* This is relatively thorough. But then again it is only 20 lines. */
#define MARCHUP		for (i = min; i < max; i++)
#define MARCHDOWN	for (i = max - 1; i >= min; i--)
#define W0		write_sx_byte(board, i, 0x55)
#define W1		write_sx_byte(board, i, 0xaa)
#define R0		if (read_sx_byte(board, i) != 0x55) return 1
#define R1		if (read_sx_byte(board, i) != 0xaa) return 1

/* This memtest takes a human-noticable time. You normally only do it
   once a boot, so I guess that it is worth it. */
static int do_memtest(struct sx_board *board, int min, int max)
{
	int i;

	/* This is a marchb. Theoretically, marchb catches much more than
	   simpler tests. In practise, the longer test just catches more
	   intermittent errors. -- REW
	   (For the theory behind memory testing see: 
	   Testing Semiconductor Memories by A.J. van de Goor.) */
	MARCHUP {
		W0;
	}
	MARCHUP {
		R0;
		W1;
		R1;
		W0;
		R0;
		W1;
	}
	MARCHUP {
		R1;
		W0;
		W1;
	}
	MARCHDOWN {
		R1;
		W0;
		W1;
		W0;
	}
	MARCHDOWN {
		R0;
		W1;
		W0;
	}

	return 0;
}

#undef MARCHUP
#undef MARCHDOWN
#undef W0
#undef W1
#undef R0
#undef R1

#define MARCHUP		for (i = min; i < max; i += 2)
#define MARCHDOWN	for (i = max - 1; i >= min; i -= 2)
#define W0		write_sx_word(board, i, 0x55aa)
#define W1		write_sx_word(board, i, 0xaa55)
#define R0		if (read_sx_word(board, i) != 0x55aa) return 1
#define R1		if (read_sx_word(board, i) != 0xaa55) return 1

#if 0
/* This memtest takes a human-noticable time. You normally only do it
   once a boot, so I guess that it is worth it. */
static int do_memtest_w(struct sx_board *board, int min, int max)
{
	int i;

	MARCHUP {
		W0;
	}
	MARCHUP {
		R0;
		W1;
		R1;
		W0;
		R0;
		W1;
	}
	MARCHUP {
		R1;
		W0;
		W1;
	}
	MARCHDOWN {
		R1;
		W0;
		W1;
		W0;
	}
	MARCHDOWN {
		R0;
		W1;
		W0;
	}

	return 0;
}
#endif

static int sx_fw_ioctl(struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	int rc = 0;
	int __user *descr = (int __user *)arg;
	int i;
	static struct sx_board *board = NULL;
	int nbytes, offset;
	unsigned long data;
	char *tmp;

	func_enter();

#if 0
	/* Removed superuser check: Sysops can use the permissions on the device
	   file to restrict access. Recommendation: Root only. (root.root 600) */
	if (!capable(CAP_SYS_ADMIN)) {
		return -EPERM;
	}
#endif

	sx_dprintk(SX_DEBUG_FIRMWARE, "IOCTL %x: %lx\n", cmd, arg);

	if (!board)
		board = &boards[0];
	if (board->flags & SX_BOARD_PRESENT) {
		sx_dprintk(SX_DEBUG_FIRMWARE, "Board present! (%x)\n",
				board->flags);
	} else {
		sx_dprintk(SX_DEBUG_FIRMWARE, "Board not present! (%x) all:",
				board->flags);
		for (i = 0; i < SX_NBOARDS; i++)
			sx_dprintk(SX_DEBUG_FIRMWARE, "<%x> ", boards[i].flags);
		sx_dprintk(SX_DEBUG_FIRMWARE, "\n");
		return -EIO;
	}

	switch (cmd) {
	case SXIO_SET_BOARD:
		sx_dprintk(SX_DEBUG_FIRMWARE, "set board to %ld\n", arg);
		if (arg >= SX_NBOARDS)
			return -EIO;
		sx_dprintk(SX_DEBUG_FIRMWARE, "not out of range\n");
		if (!(boards[arg].flags & SX_BOARD_PRESENT))
			return -EIO;
		sx_dprintk(SX_DEBUG_FIRMWARE, ".. and present!\n");
		board = &boards[arg];
		break;
	case SXIO_GET_TYPE:
		rc = -ENOENT;	/* If we manage to miss one, return error. */
		if (IS_SX_BOARD(board))
			rc = SX_TYPE_SX;
		if (IS_CF_BOARD(board))
			rc = SX_TYPE_CF;
		if (IS_SI_BOARD(board))
			rc = SX_TYPE_SI;
		if (IS_SI1_BOARD(board))
			rc = SX_TYPE_SI;
		if (IS_EISA_BOARD(board))
			rc = SX_TYPE_SI;
		sx_dprintk(SX_DEBUG_FIRMWARE, "returning type= %d\n", rc);
		break;
	case SXIO_DO_RAMTEST:
		if (sx_initialized)	/* Already initialized: better not ramtest the board.  */
			return -EPERM;
		if (IS_SX_BOARD(board)) {
			rc = do_memtest(board, 0, 0x7000);
			if (!rc)
				rc = do_memtest(board, 0, 0x7000);
			/*if (!rc) rc = do_memtest_w (board, 0, 0x7000); */
		} else {
			rc = do_memtest(board, 0, 0x7ff8);
			/* if (!rc) rc = do_memtest_w (board, 0, 0x7ff8); */
		}
		sx_dprintk(SX_DEBUG_FIRMWARE, "returning memtest result= %d\n",
			   rc);
		break;
	case SXIO_DOWNLOAD:
		if (sx_initialized)	/* Already initialized */
			return -EEXIST;
		if (!sx_reset(board))
			return -EIO;
		sx_dprintk(SX_DEBUG_INIT, "reset the board...\n");

		tmp = kmalloc(SX_CHUNK_SIZE, GFP_USER);
		if (!tmp)
			return -ENOMEM;
		get_user(nbytes, descr++);
		get_user(offset, descr++);
		get_user(data, descr++);
		while (nbytes && data) {
			for (i = 0; i < nbytes; i += SX_CHUNK_SIZE) {
				if (copy_from_user(tmp, (char __user *)data + i,
						(i + SX_CHUNK_SIZE > nbytes) ?
						nbytes - i : SX_CHUNK_SIZE)) {
					kfree(tmp);
					return -EFAULT;
				}
				memcpy_toio(board->base2 + offset + i, tmp,
						(i + SX_CHUNK_SIZE > nbytes) ?
						nbytes - i : SX_CHUNK_SIZE);
			}

			get_user(nbytes, descr++);
			get_user(offset, descr++);
			get_user(data, descr++);
		}
		kfree(tmp);
		sx_nports += sx_init_board(board);
		rc = sx_nports;
		break;
	case SXIO_INIT:
		if (sx_initialized)	/* Already initialized */
			return -EEXIST;
		/* This is not allowed until all boards are initialized... */
		for (i = 0; i < SX_NBOARDS; i++) {
			if ((boards[i].flags & SX_BOARD_PRESENT) &&
				!(boards[i].flags & SX_BOARD_INITIALIZED))
				return -EIO;
		}
		for (i = 0; i < SX_NBOARDS; i++)
			if (!(boards[i].flags & SX_BOARD_PRESENT))
				break;

		sx_dprintk(SX_DEBUG_FIRMWARE, "initing portstructs, %d boards, "
				"%d channels, first board: %d ports\n",
				i, sx_nports, boards[0].nports);
		rc = sx_init_portstructs(i, sx_nports);
		sx_init_drivers();
		if (rc >= 0)
			sx_initialized++;
		break;
	case SXIO_SETDEBUG:
		sx_debug = arg;
		break;
	case SXIO_GETDEBUG:
		rc = sx_debug;
		break;
	case SXIO_GETGSDEBUG:
	case SXIO_SETGSDEBUG:
		rc = -EINVAL;
		break;
	case SXIO_GETNPORTS:
		rc = sx_nports;
		break;
	default:
		printk(KERN_WARNING "Unknown ioctl on firmware device (%x).\n",
				cmd);
		break;
	}
	func_exit();
	return rc;
}

static void sx_break(struct tty_struct *tty, int flag)
{
	struct sx_port *port = tty->driver_data;
	int rv;

	func_enter();

	if (flag)
		rv = sx_send_command(port, HS_START, -1, HS_IDLE_BREAK);
	else
		rv = sx_send_command(port, HS_STOP, -1, HS_IDLE_OPEN);
	if (rv != 1)
		printk(KERN_ERR "sx: couldn't send break (%x).\n",
			read_sx_byte(port->board, CHAN_OFFSET(port, hi_hstat)));

	func_exit();
}

static int sx_tiocmget(struct tty_struct *tty, struct file *file)
{
	struct sx_port *port = tty->driver_data;
	return sx_getsignals(port);
}

static int sx_tiocmset(struct tty_struct *tty, struct file *file,
		unsigned int set, unsigned int clear)
{
	struct sx_port *port = tty->driver_data;
	int rts = -1, dtr = -1;

	if (set & TIOCM_RTS)
		rts = 1;
	if (set & TIOCM_DTR)
		dtr = 1;
	if (clear & TIOCM_RTS)
		rts = 0;
	if (clear & TIOCM_DTR)
		dtr = 0;

	sx_setsignals(port, dtr, rts);
	sx_reconfigure_port(port);
	return 0;
}

static int sx_ioctl(struct tty_struct *tty, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	int rc;
	struct sx_port *port = tty->driver_data;
	void __user *argp = (void __user *)arg;
	int ival;

	/* func_enter2(); */

	rc = 0;
	switch (cmd) {
	case TIOCGSOFTCAR:
		rc = put_user(((tty->termios->c_cflag & CLOCAL) ? 1 : 0),
				(unsigned __user *)argp);
		break;
	case TIOCSSOFTCAR:
		if ((rc = get_user(ival, (unsigned __user *)argp)) == 0) {
			tty->termios->c_cflag =
				(tty->termios->c_cflag & ~CLOCAL) |
				(ival ? CLOCAL : 0);
		}
		break;
	case TIOCGSERIAL:
		rc = gs_getserial(&port->gs, argp);
		break;
	case TIOCSSERIAL:
		rc = gs_setserial(&port->gs, argp);
		break;
	default:
		rc = -ENOIOCTLCMD;
		break;
	}

	/* func_exit(); */
	return rc;
}

/* The throttle/unthrottle scheme for the Specialix card is different
 * from other drivers and deserves some explanation. 
 * The Specialix hardware takes care of XON/XOFF
 * and CTS/RTS flow control itself.  This means that all we have to
 * do when signalled by the upper tty layer to throttle/unthrottle is
 * to make a note of it here.  When we come to read characters from the
 * rx buffers on the card (sx_receive_chars()) we look to see if the
 * upper layer can accept more (as noted here in sx_rx_throt[]). 
 * If it can't we simply don't remove chars from the cards buffer. 
 * When the tty layer can accept chars, we again note that here and when
 * sx_receive_chars() is called it will remove them from the cards buffer.
 * The card will notice that a ports buffer has drained below some low
 * water mark and will unflow control the line itself, using whatever
 * flow control scheme is in use for that port. -- Simon Allen
 */

static void sx_throttle(struct tty_struct *tty)
{
	struct sx_port *port = (struct sx_port *)tty->driver_data;

	func_enter2();
	/* If the port is using any type of input flow