epca.c

来自「linux 内核源代码」· C语言 代码 · 共 2,328 行 · 第 1/5 页

			/* Set baud rate, char size, stop bits, parity */
			fepcmd(ch, SETCTRLFLAGS, (unsigned) cflag, 0, 0, 0);
		}
		/*
		 * If the user has not forced CLOCAL and if the device is not a
		 * CALLOUT device (Which is always CLOCAL) we set flags such
		 * that the driver will wait on carrier detect.
		 */
		if (ts->c_cflag & CLOCAL)
			ch->asyncflags &= ~ASYNC_CHECK_CD;
		else
			ch->asyncflags |= ASYNC_CHECK_CD;
		mval = ch->m_dtr | ch->m_rts;
	} /* End CBAUD not detected */
	iflag = termios2digi_i(ch, ts->c_iflag);
	/* Check input mode flags */
	if (iflag != ch->fepiflag)  {
		ch->fepiflag = iflag;
		/*
		 * Command sets channels iflag structure on the board. Such
		 * things as input soft flow control, handling of parity
		 * errors, and break handling are all set here.
		 */
		/* break handling, parity handling, input stripping, flow control chars */
		fepcmd(ch, SETIFLAGS, (unsigned int) ch->fepiflag, 0, 0, 0);
	}
	/*
	 * Set the board mint value for this channel. This will cause hardware
	 * events to be generated each time the DCD signal (Described in mint)
	 * changes.
	 */
	writeb(ch->dcd, &bc->mint);
	if ((ts->c_cflag & CLOCAL) || (ch->digiext.digi_flags & DIGI_FORCEDCD))
		if (ch->digiext.digi_flags & DIGI_FORCEDCD)
			writeb(0, &bc->mint);
	ch->imodem = readb(&bc->mstat);
	hflow = termios2digi_h(ch, ts->c_cflag);
	if (hflow != ch->hflow)  {
		ch->hflow = hflow;
		/*
		 * Hard flow control has been selected but the board is not
		 * using it. Activate hard flow control now.
		 */
		fepcmd(ch, SETHFLOW, hflow, 0xff, 0, 1);
	}
	mval ^= ch->modemfake & (mval ^ ch->modem);

	if (ch->omodem ^ mval)  {
		ch->omodem = mval;
		/*
		 * The below command sets the DTR and RTS mstat structure. If
		 * hard flow control is NOT active these changes will drive the
		 * output of the actual DTR and RTS lines. If hard flow control
		 * is active, the changes will be saved in the mstat structure
		 * and only asserted when hard flow control is turned off.
		 */

		/* First reset DTR & RTS; then set them */
		fepcmd(ch, SETMODEM, 0, ((ch->m_dtr)|(ch->m_rts)), 0, 1);
		fepcmd(ch, SETMODEM, mval, 0, 0, 1);
	}
	if (ch->startc != ch->fepstartc || ch->stopc != ch->fepstopc)  {
		ch->fepstartc = ch->startc;
		ch->fepstopc = ch->stopc;
		/*
		 * The XON / XOFF characters have changed; propagate these
		 * changes to the card.
		 */
		fepcmd(ch, SONOFFC, ch->fepstartc, ch->fepstopc, 0, 1);
	}
	if (ch->startca != ch->fepstartca || ch->stopca != ch->fepstopca)  {
		ch->fepstartca = ch->startca;
		ch->fepstopca = ch->stopca;
		/*
		 * Similar to the above, this time the auxilarly XON / XOFF
		 * characters have changed; propagate these changes to the card.
		 */
		fepcmd(ch, SAUXONOFFC, ch->fepstartca, ch->fepstopca, 0, 1);
	}
}

/* Caller holds lock */
static void receive_data(struct channel *ch)
{
	unchar *rptr;
	struct ktermios *ts = NULL;
	struct tty_struct *tty;
	struct board_chan __iomem *bc;
	int dataToRead, wrapgap, bytesAvailable;
	unsigned int tail, head;
	unsigned int wrapmask;

	/*
	 * This routine is called by doint when a receive data event has taken
	 * place.
	 */
	globalwinon(ch);
	if (ch->statusflags & RXSTOPPED)
		return;
	tty = ch->tty;
	if (tty)
		ts = tty->termios;
	bc = ch->brdchan;
	BUG_ON(!bc);
	wrapmask = ch->rxbufsize - 1;

	/*
	 * Get the head and tail pointers to the receiver queue. Wrap the head
	 * pointer if it has reached the end of the buffer.
	 */
	head = readw(&bc->rin);
	head &= wrapmask;
	tail = readw(&bc->rout) & wrapmask;

	bytesAvailable = (head - tail) & wrapmask;
	if (bytesAvailable == 0)
		return;

	/* If CREAD bit is off or device not open, set TX tail to head */
	if (!tty || !ts || !(ts->c_cflag & CREAD))  {
		writew(head, &bc->rout);
		return;
	}

	if (tty_buffer_request_room(tty, bytesAvailable + 1) == 0)
		return;

	if (readb(&bc->orun)) {
		writeb(0, &bc->orun);
		printk(KERN_WARNING "epca; overrun! DigiBoard device %s\n",tty->name);
		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
	}
	rxwinon(ch);
	while (bytesAvailable > 0)  { /* Begin while there is data on the card */
		wrapgap = (head >= tail) ? head - tail : ch->rxbufsize - tail;
		/*
		 * Even if head has wrapped around only report the amount of
		 * data to be equal to the size - tail. Remember memcpy can't
		 * automaticly wrap around the receive buffer.
		 */
		dataToRead = (wrapgap < bytesAvailable) ? wrapgap : bytesAvailable;
		/* Make sure we don't overflow the buffer */
		dataToRead = tty_prepare_flip_string(tty, &rptr, dataToRead);
		if (dataToRead == 0)
			break;
		/*
		 * Move data read from our card into the line disciplines
		 * buffer for translation if necessary.
		 */
		memcpy_fromio(rptr, ch->rxptr + tail, dataToRead);
		tail = (tail + dataToRead) & wrapmask;
		bytesAvailable -= dataToRead;
	} /* End while there is data on the card */
	globalwinon(ch);
	writew(tail, &bc->rout);
	/* Must be called with global data */
	tty_schedule_flip(ch->tty);
}

static int info_ioctl(struct tty_struct *tty, struct file *file,
		    unsigned int cmd, unsigned long arg)
{
	switch (cmd) {
	case DIGI_GETINFO:
		{
			struct digi_info di;
			int brd;

			if (get_user(brd, (unsigned int __user *)arg))
				return -EFAULT;
			if (brd < 0 || brd >= num_cards || num_cards == 0)
				return -ENODEV;

			memset(&di, 0, sizeof(di));

			di.board = brd;
			di.status = boards[brd].status;
			di.type = boards[brd].type ;
			di.numports = boards[brd].numports ;
			/* Legacy fixups - just move along nothing to see */
			di.port = (unsigned char *)boards[brd].port ;
			di.membase = (unsigned char *)boards[brd].membase ;

			if (copy_to_user((void __user *)arg, &di, sizeof(di)))
				return -EFAULT;
			break;

		}

	case DIGI_POLLER:
		{
			int brd = arg & 0xff000000 >> 16;
			unsigned char state = arg & 0xff;

			if (brd < 0 || brd >= num_cards) {
				printk(KERN_ERR "epca: DIGI POLLER : brd not valid!\n");
				return -ENODEV;
			}
			digi_poller_inhibited = state;
			break;
		}

	case DIGI_INIT:
		{
			/*
			 * This call is made by the apps to complete the
			 * initilization of the board(s). This routine is
			 * responsible for setting the card to its initial
			 * state and setting the drivers control fields to the
			 * sutianle settings for the card in question.
			 */
			int crd;
			for (crd = 0; crd < num_cards; crd++)
				post_fep_init(crd);
			break;
		}
	default:
		return -ENOTTY;
	}
	return 0;
}

static int pc_tiocmget(struct tty_struct *tty, struct file *file)
{
	struct channel *ch = (struct channel *) tty->driver_data;
	struct board_chan __iomem *bc;
	unsigned int mstat, mflag = 0;
	unsigned long flags;

	if (ch)
		bc = ch->brdchan;
	else
		return -EINVAL;

	spin_lock_irqsave(&epca_lock, flags);
	globalwinon(ch);
	mstat = readb(&bc->mstat);
	memoff(ch);
	spin_unlock_irqrestore(&epca_lock, flags);

	if (mstat & ch->m_dtr)
		mflag |= TIOCM_DTR;
	if (mstat & ch->m_rts)
		mflag |= TIOCM_RTS;
	if (mstat & ch->m_cts)
		mflag |= TIOCM_CTS;
	if (mstat & ch->dsr)
		mflag |= TIOCM_DSR;
	if (mstat & ch->m_ri)
		mflag |= TIOCM_RI;
	if (mstat & ch->dcd)
		mflag |= TIOCM_CD;
	return mflag;
}

static int pc_tiocmset(struct tty_struct *tty, struct file *file,
		       unsigned int set, unsigned int clear)
{
	struct channel *ch = (struct channel *) tty->driver_data;
	unsigned long flags;

	if (!ch)
		return -EINVAL;

	spin_lock_irqsave(&epca_lock, flags);
	/*
	 * I think this modemfake stuff is broken. It doesn't correctly reflect
	 * the behaviour desired by the TIOCM* ioctls. Therefore this is
	 * probably broken.
	 */
	if (set & TIOCM_RTS) {
		ch->modemfake |= ch->m_rts;
		ch->modem |= ch->m_rts;
	}
	if (set & TIOCM_DTR) {
		ch->modemfake |= ch->m_dtr;
		ch->modem |= ch->m_dtr;
	}
	if (clear & TIOCM_RTS) {
		ch->modemfake |= ch->m_rts;
		ch->modem &= ~ch->m_rts;
	}
	if (clear & TIOCM_DTR) {
		ch->modemfake |= ch->m_dtr;
		ch->modem &= ~ch->m_dtr;
	}
	globalwinon(ch);
	/*
	 * The below routine generally sets up parity, baud, flow control
	 * issues, etc.... It effect both control flags and input flags.
	 */
	epcaparam(tty,ch);
	memoff(ch);
	spin_unlock_irqrestore(&epca_lock, flags);
	return 0;
}

static int pc_ioctl(struct tty_struct *tty, struct file * file,
		    unsigned int cmd, unsigned long arg)
{
	digiflow_t dflow;
	int retval;
	unsigned long flags;
	unsigned int mflag, mstat;
	unsigned char startc, stopc;
	struct board_chan __iomem *bc;
	struct channel *ch = (struct channel *) tty->driver_data;
	void __user *argp = (void __user *)arg;

	if (ch)
		bc = ch->brdchan;
	else
		return -EINVAL;

	/*
	 * For POSIX compliance we need to add more ioctls. See tty_ioctl.c in
	 * /usr/src/linux/drivers/char for a good example. In particular think
	 * about adding TCSETAF, TCSETAW, TCSETA, TCSETSF, TCSETSW, TCSETS.
	 */
	switch (cmd) {
	case TCSBRK:	/* SVID version: non-zero arg --> no break */
		retval = tty_check_change(tty);
		if (retval)
			return retval;
		/* Setup an event to indicate when the transmit buffer empties */
		spin_lock_irqsave(&epca_lock, flags);
		setup_empty_event(tty,ch);
		spin_unlock_irqrestore(&epca_lock, flags);
		tty_wait_until_sent(tty, 0);
		if (!arg)
			digi_send_break(ch, HZ / 4);    /* 1/4 second */
		return 0;
	case TCSBRKP:	/* support for POSIX tcsendbreak() */
		retval = tty_check_change(tty);
		if (retval)
			return retval;

		/* Setup an event to indicate when the transmit buffer empties */
		spin_lock_irqsave(&epca_lock, flags);
		setup_empty_event(tty,ch);
		spin_unlock_irqrestore(&epca_lock, flags);
		tty_wait_until_sent(tty, 0);
		digi_send_break(ch, arg ? arg*(HZ/10) : HZ/4);
		return 0;
	case TIOCGSOFTCAR:
		if (put_user(C_CLOCAL(tty)?1:0, (unsigned long __user *)arg))
			return -EFAULT;
		return 0;
	case TIOCSSOFTCAR:
		{
			unsigned int value;

			if (get_user(value, (unsigned __user *)argp))
				return -EFAULT;
			tty->termios->c_cflag =
				((tty->termios->c_cflag & ~CLOCAL) |
				 (value ? CLOCAL : 0));
			return 0;
		}
	case TIOCMODG:
		mflag = pc_tiocmget(tty, file);
		if (put_user(mflag, (unsigned long __user *)argp))
			return -EFAULT;
		break;
	case TIOCMODS:
		if (get_user(mstat, (unsigned __user *)argp))
			return -EFAULT;
		return pc_tiocmset(tty, file, mstat, ~mstat);
	case TIOCSDTR:
		spin_lock_irqsave(&epca_lock, flags);
		ch->omodem |= ch->m_dtr;
		globalwinon(ch);
		fepcmd(ch, SETMODEM, ch->m_dtr, 0, 10, 1);
		memoff(ch);
		spin_unlock_irqrestore(&epca_lock, flags);
		break;

	case TIOCCDTR:
		spin_lock_irqsave(&epca_lock, flags);
		ch->omodem &= ~ch->m_dtr;
		globalwinon(ch);
		fepcmd(ch, SETMODEM, 0, ch->m_dtr, 10, 1);
		memoff(ch);
		spin_unlock_irqrestore(&epca_lock, flags);
		break;
	case DIGI_GETA:
		if (copy_to_user(argp, &ch->digiext, sizeof(digi_t)))
			return -EFAULT;
		break;
	case DIGI_SETAW:
	case DIGI_SETAF:
		if (cmd == DIGI_SETAW) {
			/* Setup an event to indicate when the transmit buffer empties */
			spin_lock_irqsave(&epca_lock, flags);
			setup_empty_event(tty,ch);
			spin_unlock_irqrestore(&epca_lock, flags);
			tty_wait_until_sent(tty, 0);
		} else {
			/* ldisc lock already held in ioctl */
			if (tty->ldisc.flush_buffer)
				tty->ldisc.flush_buffer(tty);
		}
		/* Fall Thru */
	case DIGI_SETA:
		if (copy_from_user(&ch->digiext, argp, sizeof(digi_t)))
			return -EFAULT;

		if (ch->digiext.digi_flags & DIGI_ALTPIN)  {
			ch->dcd = ch->m_dsr;
			ch->dsr = ch->m_dcd;
		} else {
			ch->dcd = ch->m_dcd;
			ch->dsr = ch->m_dsr;
			}

		spin_lock_irqsave(&epca_lock, flags);
		globalwinon(ch);

		/*
		 * The below routine generally sets up parity, baud, flow
		 * control issues, etc.... It effect both control flags and
		 * input flags.
		 */
		epcaparam(tty,ch);
		memoff(ch);
		spin_unlock_irqrestore(&epca_lock, flags);
		break;

	case DIGI_GETFLOW:
	case DIGI_GETAFLOW:
		spin_lock_irqsave(&epca_lock, flags);
		globalwinon(ch);
		if (cmd == DIGI_GETFLOW) {
			dflow.startc = readb(&bc->startc);
			dflow.stopc = readb(&bc->stopc);
		} else {
			dflow.startc = readb(&bc->startca);
			dflow.stopc = readb(&bc->stopca);
		}
		memoff(ch);
		spin_unlock_irqrestore(&epca_lock, flags);

		if (copy_to_user(argp, &dflow, sizeof(dflow)))
			return -EFAULT;
		break;

	case DIGI_SETAFLOW:
	case DIGI_SETFLOW:
		if (cmd == DIGI_SETFLOW) {
			startc = ch->startc;
			stopc = ch->stopc;
		} else {
			startc = ch->startca;
			stopc = ch->stopca;
		}

		if (copy_from_user(&dflow, argp, sizeof(dflow)))
			return -EFAULT;

		if (dflow.startc != startc || dflow.stopc != stopc) { /* Begin  if setflow toggled */
			spin_lock_irqsave(&epca_lock, flags);
			globalwinon(ch);

			if (cmd == DI