rocket.c

来自「linux 内核源代码」· C语言 代码 · 共 2,326 行 · 第 1/5 页

			break;
		}
		if (!(info->flags & ROCKET_CLOSING) && (do_clocal || (sGetChanStatusLo(&info->channel) & CD_ACT)))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
#ifdef ROCKET_DEBUG_OPEN
		printk(KERN_INFO "block_til_ready blocking: ttyR%d, count = %d, flags=0x%0x\n",
		     info->line, info->count, info->flags);
#endif
		schedule();	/*  Don't hold spinlock here, will hang PC */
	}
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&info->open_wait, &wait);

	spin_lock_irqsave(&info->slock, flags);

	if (extra_count)
		info->count++;
	info->blocked_open--;

	spin_unlock_irqrestore(&info->slock, flags);

#ifdef ROCKET_DEBUG_OPEN
	printk(KERN_INFO "block_til_ready after blocking: ttyR%d, count = %d\n",
	       info->line, info->count);
#endif
	if (retval)
		return retval;
	info->flags |= ROCKET_NORMAL_ACTIVE;
	return 0;
}

/*
 *  Exception handler that opens a serial port.  Creates xmit_buf storage, fills in 
 *  port's r_port struct.  Initializes the port hardware.  
 */
static int rp_open(struct tty_struct *tty, struct file *filp)
{
	struct r_port *info;
	int line = 0, retval;
	CHANNEL_t *cp;
	unsigned long page;

	line = TTY_GET_LINE(tty);
	if ((line < 0) || (line >= MAX_RP_PORTS) || ((info = rp_table[line]) == NULL))
		return -ENXIO;

	page = __get_free_page(GFP_KERNEL);
	if (!page)
		return -ENOMEM;

	if (info->flags & ROCKET_CLOSING) {
		retval = wait_for_completion_interruptible(&info->close_wait);
		free_page(page);
		if (retval)
			return retval;
		return ((info->flags & ROCKET_HUP_NOTIFY) ? -EAGAIN : -ERESTARTSYS);
	}

	/*
	 * We must not sleep from here until the port is marked fully in use.
	 */
	if (info->xmit_buf)
		free_page(page);
	else
		info->xmit_buf = (unsigned char *) page;

	tty->driver_data = info;
	info->tty = tty;

	if (info->count++ == 0) {
		atomic_inc(&rp_num_ports_open);

#ifdef ROCKET_DEBUG_OPEN
		printk(KERN_INFO "rocket mod++ = %d...", atomic_read(&rp_num_ports_open));
#endif
	}
#ifdef ROCKET_DEBUG_OPEN
	printk(KERN_INFO "rp_open ttyR%d, count=%d\n", info->line, info->count);
#endif

	/*
	 * Info->count is now 1; so it's safe to sleep now.
	 */
	if ((info->flags & ROCKET_INITIALIZED) == 0) {
		cp = &info->channel;
		sSetRxTrigger(cp, TRIG_1);
		if (sGetChanStatus(cp) & CD_ACT)
			info->cd_status = 1;
		else
			info->cd_status = 0;
		sDisRxStatusMode(cp);
		sFlushRxFIFO(cp);
		sFlushTxFIFO(cp);

		sEnInterrupts(cp, (TXINT_EN | MCINT_EN | RXINT_EN | SRCINT_EN | CHANINT_EN));
		sSetRxTrigger(cp, TRIG_1);

		sGetChanStatus(cp);
		sDisRxStatusMode(cp);
		sClrTxXOFF(cp);

		sDisCTSFlowCtl(cp);
		sDisTxSoftFlowCtl(cp);

		sEnRxFIFO(cp);
		sEnTransmit(cp);

		info->flags |= ROCKET_INITIALIZED;

		/*
		 * Set up the tty->alt_speed kludge
		 */
		if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_HI)
			info->tty->alt_speed = 57600;
		if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_VHI)
			info->tty->alt_speed = 115200;
		if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_SHI)
			info->tty->alt_speed = 230400;
		if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_WARP)
			info->tty->alt_speed = 460800;

		configure_r_port(info, NULL);
		if (tty->termios->c_cflag & CBAUD) {
			sSetDTR(cp);
			sSetRTS(cp);
		}
	}
	/*  Starts (or resets) the maint polling loop */
	mod_timer(&rocket_timer, jiffies + POLL_PERIOD);

	retval = block_til_ready(tty, filp, info);
	if (retval) {
#ifdef ROCKET_DEBUG_OPEN
		printk(KERN_INFO "rp_open returning after block_til_ready with %d\n", retval);
#endif
		return retval;
	}
	return 0;
}

/*
 *  Exception handler that closes a serial port. info->count is considered critical. 
 */
static void rp_close(struct tty_struct *tty, struct file *filp)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	unsigned long flags;
	int timeout;
	CHANNEL_t *cp;
	
	if (rocket_paranoia_check(info, "rp_close"))
		return;

#ifdef ROCKET_DEBUG_OPEN
	printk(KERN_INFO "rp_close ttyR%d, count = %d\n", info->line, info->count);
#endif

	if (tty_hung_up_p(filp))
		return;
	spin_lock_irqsave(&info->slock, flags);

	if ((tty->count == 1) && (info->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  Info->count should always
		 * be one in these conditions.  If it's greater than
		 * one, we've got real problems, since it means the
		 * serial port won't be shutdown.
		 */
		printk(KERN_INFO "rp_close: bad serial port count; tty->count is 1, "
		       "info->count is %d\n", info->count);
		info->count = 1;
	}
	if (--info->count < 0) {
		printk(KERN_INFO "rp_close: bad serial port count for ttyR%d: %d\n",
		       info->line, info->count);
		info->count = 0;
	}
	if (info->count) {
		spin_unlock_irqrestore(&info->slock, flags);
		return;
	}
	info->flags |= ROCKET_CLOSING;
	spin_unlock_irqrestore(&info->slock, flags);

	cp = &info->channel;

	/*
	 * Notify the line discpline to only process XON/XOFF characters
	 */
	tty->closing = 1;

	/*
	 * If transmission was throttled by the application request,
	 * just flush the xmit buffer.
	 */
	if (tty->flow_stopped)
		rp_flush_buffer(tty);

	/*
	 * Wait for the transmit buffer to clear
	 */
	if (info->closing_wait != ROCKET_CLOSING_WAIT_NONE)
		tty_wait_until_sent(tty, info->closing_wait);
	/*
	 * Before we drop DTR, make sure the UART transmitter
	 * has completely drained; this is especially
	 * important if there is a transmit FIFO!
	 */
	timeout = (sGetTxCnt(cp) + 1) * HZ / info->cps;
	if (timeout == 0)
		timeout = 1;
	rp_wait_until_sent(tty, timeout);
	clear_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);

	sDisTransmit(cp);
	sDisInterrupts(cp, (TXINT_EN | MCINT_EN | RXINT_EN | SRCINT_EN | CHANINT_EN));
	sDisCTSFlowCtl(cp);
	sDisTxSoftFlowCtl(cp);
	sClrTxXOFF(cp);
	sFlushRxFIFO(cp);
	sFlushTxFIFO(cp);
	sClrRTS(cp);
	if (C_HUPCL(tty))
		sClrDTR(cp);

	if (TTY_DRIVER_FLUSH_BUFFER_EXISTS(tty))
		TTY_DRIVER_FLUSH_BUFFER(tty);
		
	tty_ldisc_flush(tty);

	clear_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);

	if (info->blocked_open) {
		if (info->close_delay) {
			msleep_interruptible(jiffies_to_msecs(info->close_delay));
		}
		wake_up_interruptible(&info->open_wait);
	} else {
		if (info->xmit_buf) {
			free_page((unsigned long) info->xmit_buf);
			info->xmit_buf = NULL;
		}
	}
	info->flags &= ~(ROCKET_INITIALIZED | ROCKET_CLOSING | ROCKET_NORMAL_ACTIVE);
	tty->closing = 0;
	complete_all(&info->close_wait);
	atomic_dec(&rp_num_ports_open);

#ifdef ROCKET_DEBUG_OPEN
	printk(KERN_INFO "rocket mod-- = %d...", atomic_read(&rp_num_ports_open));
	printk(KERN_INFO "rp_close ttyR%d complete shutdown\n", info->line);
#endif

}

static void rp_set_termios(struct tty_struct *tty,
			   struct ktermios *old_termios)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;
	unsigned cflag;

	if (rocket_paranoia_check(info, "rp_set_termios"))
		return;

	cflag = tty->termios->c_cflag;

	if (cflag == old_termios->c_cflag)
		return;

	/*
	 * This driver doesn't support CS5 or CS6
	 */
	if (((cflag & CSIZE) == CS5) || ((cflag & CSIZE) == CS6))
		tty->termios->c_cflag =
		    ((cflag & ~CSIZE) | (old_termios->c_cflag & CSIZE));

	configure_r_port(info, old_termios);

	cp = &info->channel;

	/* Handle transition to B0 status */
	if ((old_termios->c_cflag & CBAUD) && !(tty->termios->c_cflag & CBAUD)) {
		sClrDTR(cp);
		sClrRTS(cp);
	}

	/* Handle transition away from B0 status */
	if (!(old_termios->c_cflag & CBAUD) && (tty->termios->c_cflag & CBAUD)) {
		if (!tty->hw_stopped || !(tty->termios->c_cflag & CRTSCTS))
			sSetRTS(cp);
		sSetDTR(cp);
	}

	if ((old_termios->c_cflag & CRTSCTS) && !(tty->termios->c_cflag & CRTSCTS)) {
		tty->hw_stopped = 0;
		rp_start(tty);
	}
}

static void rp_break(struct tty_struct *tty, int break_state)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	unsigned long flags;

	if (rocket_paranoia_check(info, "rp_break"))
		return;

	spin_lock_irqsave(&info->slock, flags);
	if (break_state == -1)
		sSendBreak(&info->channel);
	else
		sClrBreak(&info->channel);
	spin_unlock_irqrestore(&info->slock, flags);
}

/*
 * sGetChanRI used to be a macro in rocket_int.h. When the functionality for
 * the UPCI boards was added, it was decided to make this a function because
 * the macro was getting too complicated. All cases except the first one
 * (UPCIRingInd) are taken directly from the original macro.
 */
static int sGetChanRI(CHANNEL_T * ChP)
{
	CONTROLLER_t *CtlP = ChP->CtlP;
	int ChanNum = ChP->ChanNum;
	int RingInd = 0;

	if (CtlP->UPCIRingInd)
		RingInd = !(sInB(CtlP->UPCIRingInd) & sBitMapSetTbl[ChanNum]);
	else if (CtlP->AltChanRingIndicator)
		RingInd = sInB((ByteIO_t) (ChP->ChanStat + 8)) & DSR_ACT;
	else if (CtlP->boardType == ROCKET_TYPE_PC104)
		RingInd = !(sInB(CtlP->AiopIO[3]) & sBitMapSetTbl[ChanNum]);

	return RingInd;
}

/********************************************************************************************/
/*  Here are the routines used by rp_ioctl.  These are all called from exception handlers.  */

/*
 *  Returns the state of the serial modem control lines.  These next 2 functions 
 *  are the way kernel versions > 2.5 handle modem control lines rather than IOCTLs.
 */
static int rp_tiocmget(struct tty_struct *tty, struct file *file)
{
	struct r_port *info = (struct r_port *)tty->driver_data;
	unsigned int control, result, ChanStatus;

	ChanStatus = sGetChanStatusLo(&info->channel);
	control = info->channel.TxControl[3];
	result = ((control & SET_RTS) ? TIOCM_RTS : 0) | 
		((control & SET_DTR) ?  TIOCM_DTR : 0) |
		((ChanStatus & CD_ACT) ? TIOCM_CAR : 0) |
		(sGetChanRI(&info->channel) ? TIOCM_RNG : 0) |
		((ChanStatus & DSR_ACT) ? TIOCM_DSR : 0) |
		((ChanStatus & CTS_ACT) ? TIOCM_CTS : 0);

	return result;
}

/* 
 *  Sets the modem control lines
 */
static int rp_tiocmset(struct tty_struct *tty, struct file *file,
		    unsigned int set, unsigned int clear)
{
	struct r_port *info = (struct r_port *)tty->driver_data;

	if (set & TIOCM_RTS)
		info->channel.TxControl[3] |= SET_RTS;
	if (set & TIOCM_DTR)
		info->channel.TxControl[3] |= SET_DTR;
	if (clear & TIOCM_RTS)
		info->channel.TxControl[3] &= ~SET_RTS;
	if (clear & TIOCM_DTR)
		info->channel.TxControl[3] &= ~SET_DTR;

	sOutDW(info->channel.IndexAddr, *(DWord_t *) & (info->channel.TxControl[0]));
	return 0;
}

static int get_config(struct r_port *info, struct rocket_config __user *retinfo)
{
	struct rocket_config tmp;

	if (!retinfo)
		return -EFAULT;
	memset(&tmp, 0, sizeof (tmp));
	tmp.line = info->line;
	tmp.flags = info->flags;
	tmp.close_delay = info->close_delay;
	tmp.closing_wait = info->closing_wait;
	tmp.port = rcktpt_io_addr[(info->line >> 5) & 3];

	if (copy_to_user(retinfo, &tmp, sizeof (*retinfo)))
		return -EFAULT;
	return 0;
}

static int set_config(struct r_port *info, struct rocket_config __user *new_info)
{
	struct rocket_config new_serial;

	if (copy_from_user(&new_serial, new_info, sizeof (new_serial)))
		return -EFAULT;

	if (!capable(CAP_SYS_ADMIN))
	{
		if ((new_serial.flags & ~ROCKET_USR_MASK) != (info->flags & ~ROCKET_USR_MASK))
			return -EPERM;
		info->flags = ((info->flags & ~ROCKET_USR_MASK) | (new_serial.flags & ROCKET_USR_MASK));
		configure_r_port(info, NULL);
		return 0;
	}

	info->flags = ((info->flags & ~ROCKET_FLAGS) | (new_serial.flags & ROCKET_FLAGS));
	info->close_delay = new_serial.close_delay;
	info->closing_wait = new_serial.closing_wait;

	if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_HI)
		info->tty->alt_speed = 57600;
	if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_VHI)
		info->tty->alt_speed = 115200;
	if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_SHI)
		info->tty->alt_speed = 230400;
	if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_WARP)
		info->tty->alt_speed = 460800;

	configure_r_port(info, NULL);
	return 0;
}

/*
 *  This function fills in a rocket_ports struct with information
 *  about what boards/ports are in the system.  This info is passed
 *  to user space.  See setrocket.c where the info is used to create
 *  the /dev/ttyRx ports.
 */
static int get_ports(struct r_port *info, struct rocket_ports __user *retports)
{
	struct rocket_ports tmp;
	int board;

	if (!retports)
		return -EFAULT;
	memset(&tmp, 0, sizeof (tmp));
	tmp.tty_major = rocket_driver->major;

	for (board = 0; board < 4; board++) {
		tmp.rocketModel[board].model = rocketModel[board].model;
		strcpy(tmp.rocketModel[board].modelString, rocketModel[board].modelString);
		tmp.rocketModel[board].numPorts = rocketModel[board].numPorts;
		tmp.rocketModel[board].loadrm2 = rocketModel[board].loadrm2;
		tmp.rocketModel[board].startingPortNumber = rocketModel[board].startingPortNumber;
	}
	if (copy_to_user(retports, &tmp, sizeof (*retports)))
		return -EFAULT;
	return 0;
}