riscom8.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,842 行 · 第 1/3 页

				rc_check_modem(bp);
			else
				printk(KERN_WARNING "rc%d: Bad modem ack "
						    "0x%02x.\n",
				       board_No(bp), ack);
		
		} 

		rc_out(bp, CD180_EOIR, 0);   /* Mark end of interrupt */
		rc_out(bp, RC_CTOUT, 0);     /* Clear timeout flag    */
	}
	return IRQ_RETVAL(handled);
}

/*
 *  Routines for open & close processing.
 */

/* Called with disabled interrupts */
static inline int rc_setup_board(struct riscom_board * bp)
{
	int error;

	if (bp->flags & RC_BOARD_ACTIVE) 
		return 0;
	
	error = request_irq(bp->irq, rc_interrupt, SA_INTERRUPT,
			    "RISCom/8", NULL);
	if (error) 
		return error;
	
	rc_out(bp, RC_CTOUT, 0);       		/* Just in case         */
	bp->DTR = ~0;
	rc_out(bp, RC_DTR, bp->DTR);	        /* Drop DTR on all ports */
	
	IRQ_to_board[bp->irq] = bp;
	bp->flags |= RC_BOARD_ACTIVE;
	
	return 0;
}

/* Called with disabled interrupts */
static inline void rc_shutdown_board(struct riscom_board *bp)
{
	if (!(bp->flags & RC_BOARD_ACTIVE))
		return;
	
	bp->flags &= ~RC_BOARD_ACTIVE;
	
	free_irq(bp->irq, NULL);
	IRQ_to_board[bp->irq] = NULL;
	
	bp->DTR = ~0;
	rc_out(bp, RC_DTR, bp->DTR);	       /* Drop DTR on all ports */
	
}

/*
 * Setting up port characteristics. 
 * Must be called with disabled interrupts
 */
static void rc_change_speed(struct riscom_board *bp, struct riscom_port *port)
{
	struct tty_struct *tty;
	unsigned long baud;
	long tmp;
	unsigned char cor1 = 0, cor3 = 0;
	unsigned char mcor1 = 0, mcor2 = 0;
	
	if (!(tty = port->tty) || !tty->termios)
		return;

	port->IER  = 0;
	port->COR2 = 0;
	port->MSVR = MSVR_RTS;
	
	baud = C_BAUD(tty);
	
	if (baud & CBAUDEX) {
		baud &= ~CBAUDEX;
		if (baud < 1 || baud > 2) 
			port->tty->termios->c_cflag &= ~CBAUDEX;
		else
			baud += 15;
	}
	if (baud == 15)  {
		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
			baud ++;
		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
			baud += 2;
	}
	
	/* Select port on the board */
	rc_out(bp, CD180_CAR, port_No(port));
	
	if (!baud_table[baud])  {
		/* Drop DTR & exit */
		bp->DTR |= (1u << port_No(port));
		rc_out(bp, RC_DTR, bp->DTR);
		return;
	} else  {
		/* Set DTR on */
		bp->DTR &= ~(1u << port_No(port));
		rc_out(bp, RC_DTR, bp->DTR);
	}
	
	/*
	 * Now we must calculate some speed depended things 
	 */
	
	/* Set baud rate for port */
	tmp = (((RC_OSCFREQ + baud_table[baud]/2) / baud_table[baud] +
		CD180_TPC/2) / CD180_TPC);

	rc_out(bp, CD180_RBPRH, (tmp >> 8) & 0xff); 
	rc_out(bp, CD180_TBPRH, (tmp >> 8) & 0xff); 
	rc_out(bp, CD180_RBPRL, tmp & 0xff); 
	rc_out(bp, CD180_TBPRL, tmp & 0xff);
	
	baud = (baud_table[baud] + 5) / 10;   /* Estimated CPS */
	
	/* Two timer ticks seems enough to wakeup something like SLIP driver */
	tmp = ((baud + HZ/2) / HZ) * 2 - CD180_NFIFO;		
	port->wakeup_chars = (tmp < 0) ? 0 : ((tmp >= SERIAL_XMIT_SIZE) ?
					      SERIAL_XMIT_SIZE - 1 : tmp);
	
	/* Receiver timeout will be transmission time for 1.5 chars */
	tmp = (RISCOM_TPS + RISCOM_TPS/2 + baud/2) / baud;
	tmp = (tmp > 0xff) ? 0xff : tmp;
	rc_out(bp, CD180_RTPR, tmp);
	
	switch (C_CSIZE(tty))  {
	 case CS5:
		cor1 |= COR1_5BITS;
		break;
	 case CS6:
		cor1 |= COR1_6BITS;
		break;
	 case CS7:
		cor1 |= COR1_7BITS;
		break;
	 case CS8:
		cor1 |= COR1_8BITS;
		break;
	}
	
	if (C_CSTOPB(tty)) 
		cor1 |= COR1_2SB;
	
	cor1 |= COR1_IGNORE;
	if (C_PARENB(tty))  {
		cor1 |= COR1_NORMPAR;
		if (C_PARODD(tty)) 
			cor1 |= COR1_ODDP;
		if (I_INPCK(tty)) 
			cor1 &= ~COR1_IGNORE;
	}
	/* Set marking of some errors */
	port->mark_mask = RCSR_OE | RCSR_TOUT;
	if (I_INPCK(tty)) 
		port->mark_mask |= RCSR_FE | RCSR_PE;
	if (I_BRKINT(tty) || I_PARMRK(tty)) 
		port->mark_mask |= RCSR_BREAK;
	if (I_IGNPAR(tty)) 
		port->mark_mask &= ~(RCSR_FE | RCSR_PE);
	if (I_IGNBRK(tty))  {
		port->mark_mask &= ~RCSR_BREAK;
		if (I_IGNPAR(tty)) 
			/* Real raw mode. Ignore all */
			port->mark_mask &= ~RCSR_OE;
	}
	/* Enable Hardware Flow Control */
	if (C_CRTSCTS(tty))  {
#ifdef RISCOM_BRAIN_DAMAGED_CTS
		port->IER |= IER_DSR | IER_CTS;
		mcor1 |= MCOR1_DSRZD | MCOR1_CTSZD;
		mcor2 |= MCOR2_DSROD | MCOR2_CTSOD;
		tty->hw_stopped = !(rc_in(bp, CD180_MSVR) & (MSVR_CTS|MSVR_DSR));
#else
		port->COR2 |= COR2_CTSAE;
#endif
	}
	/* Enable Software Flow Control. FIXME: I'm not sure about this */
	/* Some people reported that it works, but I still doubt */
	if (I_IXON(tty))  {
		port->COR2 |= COR2_TXIBE;
		cor3 |= (COR3_FCT | COR3_SCDE);
		if (I_IXANY(tty))
			port->COR2 |= COR2_IXM;
		rc_out(bp, CD180_SCHR1, START_CHAR(tty));
		rc_out(bp, CD180_SCHR2, STOP_CHAR(tty));
		rc_out(bp, CD180_SCHR3, START_CHAR(tty));
		rc_out(bp, CD180_SCHR4, STOP_CHAR(tty));
	}
	if (!C_CLOCAL(tty))  {
		/* Enable CD check */
		port->IER |= IER_CD;
		mcor1 |= MCOR1_CDZD;
		mcor2 |= MCOR2_CDOD;
	}
	
	if (C_CREAD(tty)) 
		/* Enable receiver */
		port->IER |= IER_RXD;
	
	/* Set input FIFO size (1-8 bytes) */
	cor3 |= RISCOM_RXFIFO; 
	/* Setting up CD180 channel registers */
	rc_out(bp, CD180_COR1, cor1);
	rc_out(bp, CD180_COR2, port->COR2);
	rc_out(bp, CD180_COR3, cor3);
	/* Make CD180 know about registers change */
	rc_wait_CCR(bp);
	rc_out(bp, CD180_CCR, CCR_CORCHG1 | CCR_CORCHG2 | CCR_CORCHG3);
	/* Setting up modem option registers */
	rc_out(bp, CD180_MCOR1, mcor1);
	rc_out(bp, CD180_MCOR2, mcor2);
	/* Enable CD180 transmitter & receiver */
	rc_wait_CCR(bp);
	rc_out(bp, CD180_CCR, CCR_TXEN | CCR_RXEN);
	/* Enable interrupts */
	rc_out(bp, CD180_IER, port->IER);
	/* And finally set RTS on */
	rc_out(bp, CD180_MSVR, port->MSVR);
}

/* Must be called with interrupts enabled */
static int rc_setup_port(struct riscom_board *bp, struct riscom_port *port)
{
	unsigned long flags;
	
	if (port->flags & ASYNC_INITIALIZED)
		return 0;
	
	if (!port->xmit_buf) {
		/* We may sleep in get_zeroed_page() */
		unsigned long tmp;
		
		if (!(tmp = get_zeroed_page(GFP_KERNEL)))
			return -ENOMEM;
		    
		if (port->xmit_buf) {
			free_page(tmp);
			return -ERESTARTSYS;
		}
		port->xmit_buf = (unsigned char *) tmp;
	}
		
	save_flags(flags); cli();
		
	if (port->tty) 
		clear_bit(TTY_IO_ERROR, &port->tty->flags);
		
	if (port->count == 1) 
		bp->count++;
		
	port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
	rc_change_speed(bp, port);
	port->flags |= ASYNC_INITIALIZED;
		
	restore_flags(flags);
	return 0;
}

/* Must be called with interrupts disabled */
static void rc_shutdown_port(struct riscom_board *bp, struct riscom_port *port)
{
	struct tty_struct *tty;
	
	if (!(port->flags & ASYNC_INITIALIZED)) 
		return;
	
#ifdef RC_REPORT_OVERRUN
	printk(KERN_INFO "rc%d: port %d: Total %ld overruns were detected.\n",
	       board_No(bp), port_No(port), port->overrun);
#endif	
#ifdef RC_REPORT_FIFO
	{
		int i;
		
		printk(KERN_INFO "rc%d: port %d: FIFO hits [ ",
		       board_No(bp), port_No(port));
		for (i = 0; i < 10; i++)  {
			printk("%ld ", port->hits[i]);
		}
		printk("].\n");
	}
#endif	
	if (port->xmit_buf)  {
		free_page((unsigned long) port->xmit_buf);
		port->xmit_buf = NULL;
	}

	if (!(tty = port->tty) || C_HUPCL(tty))  {
		/* Drop DTR */
		bp->DTR |= (1u << port_No(port));
		rc_out(bp, RC_DTR, bp->DTR);
	}
	
        /* Select port */
	rc_out(bp, CD180_CAR, port_No(port));
	/* Reset port */
	rc_wait_CCR(bp);
	rc_out(bp, CD180_CCR, CCR_SOFTRESET);
	/* Disable all interrupts from this port */
	port->IER = 0;
	rc_out(bp, CD180_IER, port->IER);
	
	if (tty)  
		set_bit(TTY_IO_ERROR, &tty->flags);
	port->flags &= ~ASYNC_INITIALIZED;
	
	if (--bp->count < 0)  {
		printk(KERN_INFO "rc%d: rc_shutdown_port: "
				 "bad board count: %d\n",
		       board_No(bp), bp->count);
		bp->count = 0;
	}
	
	/*
	 * If this is the last opened port on the board
	 * shutdown whole board
	 */
	if (!bp->count) 
		rc_shutdown_board(bp);
}

	
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct riscom_port *port)
{
	DECLARE_WAITQUEUE(wait, current);
	struct riscom_board *bp = port_Board(port);
	int    retval;
	int    do_clocal = 0;
	int    CD;

	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&port->close_wait);
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	/*
	 * If non-blocking mode is set, or the port is not enabled,
	 * then make the check up front and then exit.
	 */
	if ((filp->f_flags & O_NONBLOCK) ||
	    (tty->flags & (1 << TTY_IO_ERROR))) {
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	if (C_CLOCAL(tty))  
		do_clocal = 1;

	/*
	 * Block waiting for the carrier detect and the line to become
	 * free (i.e., not in use by the callout).  While we are in
	 * this loop, info->count is dropped by one, so that
	 * rs_close() knows when to free things.  We restore it upon
	 * exit, either normal or abnormal.
	 */
	retval = 0;
	add_wait_queue(&port->open_wait, &wait);
	cli();
	if (!tty_hung_up_p(filp))
		port->count--;
	sti();
	port->blocked_open++;
	while (1) {
		cli();
		rc_out(bp, CD180_CAR, port_No(port));
		CD = rc_in(bp, CD180_MSVR) & MSVR_CD;
		rc_out(bp, CD180_MSVR, MSVR_RTS);
		bp->DTR &= ~(1u << port_No(port));
		rc_out(bp, RC_DTR, bp->DTR);
		sti();
		set_current_state(TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) ||
		    !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;	
			break;
		}
		if (!(port->flags & ASYNC_CLOSING) &&
		    (do_clocal || CD))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	current->state = TASK_RUNNING;
	remove_wait_queue(&port->open_wait, &wait);
	if (!tty_hung_up_p(filp))
		port->count++;
	port->blocked_open--;
	if (retval)
		return retval;
	
	port->flags |= ASYNC_NORMAL_ACTIVE;
	return 0;
}	

static int rc_open(struct tty_struct * tty, struct file * filp)
{
	int board;
	int error;
	struct riscom_port * port;
	struct riscom_board * bp;
	
	board = RC_BOARD(tty->index);
	if (board >= RC_NBOARD || !(rc_board[board].flags & RC_BOARD_PRESENT))
		return -ENODEV;
	
	bp = &rc_board[board];
	port = rc_port + board * RC_NPORT + RC_PORT(tty->index);
	if (rc_paranoia_check(port, tty->name, "rc_open"))
		return -ENODEV;
	
	if ((error = rc_setup_board(bp))) 
		return error;
		
	port->count++;
	tty->driver_data = port;
	port->tty = tty;
	
	if ((error = rc_setup_port(bp, port))) 
		return error;
	
	if ((error = block_til_ready(tty, filp, port)))
		return error;
	
	return 0;
}

static void rc_close(struct tty_struct * tty, struct file * filp)
{
	struct riscom_port *port = (struct riscom_port *) tty->driver_data;
	struct riscom_board *bp;
	unsigned long flags;
	unsigned long timeout;
	
	if (!port || rc_paranoia_check(port, tty->name, "close"))
		return;
	
	save_flags(flags); cli();
	if (tty_hung_up_p(filp))
		goto out;
	
	bp = port_Board(port);
	if ((tty->count == 1) && (port->count != 1))  {
		printk(KERN_INFO "rc%d: rc_close: bad port count;"
		       " tty->count is 1, port count is %d\n",
		       board_No(bp), port->count);
		port->count = 1;
	}
	if (--port->count < 0)  {
		printk(KERN_INFO "rc%d: rc_close: bad port count "
				 "for tty%d: %d\n",
		       board_No(bp), port_No(port), port->count);
		port->count = 0;
	}
	if (port->count)
		goto out;
	port->flags |= ASYNC_CLOSING;
	/*
	 * Now we wait for the transmit buffer to clear; and we notify 
	 * the line discipline to only process XON/XOFF characters.
	 */
	tty->closing = 1;
	if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
		tty_wait_until_sent(tty, port->closing_wait);
	/*
	 * At this point we stop accepting input.  To do this, we
	 * disable the receive line status interrupts, and tell the
	 * interrupt driver to stop checking the data ready bit in the
	 * line status register.
	 */
	port->IER &= ~IER_RXD;
	if (port->flags & ASYNC_INITIALIZED) {
		port->IER &= ~IER_TXRDY;
		port->IER |= IER_TXEMPTY;
		rc_out(bp, CD180_CAR, port_No(port));
		rc_out(bp, CD180_IER, port->IER);
		/*
		 * Before we drop DTR, make sure the UART transmitter
		 * has completely drained; this is especially
		 * important if there is a transmit FIFO!
		 */
		timeout = jiffies+HZ;
		while(port->IER & IER_TXEMPTY)  {
			current->state = TASK_INTERRUPTIBLE;
 			schedule_timeout(port->timeout);
			if (time_after(jiffies, timeout))
				break;
		}
	}
	rc_shutdown_port(bp, port);
	if (tty->driver->flush_buffer)
		tty->driver->flush_buffer(tty);
	tty_ldisc_flush(tty);

	tty->closing = 0;
	port->event = 0;
	port->tty = NULL;
	if (port->blocked_open) {
		if (port->close_delay) {
			current->state = TASK_INTERRUPTIBLE;
			schedule_timeout(port->close_delay);
		}
		wake_up_interruptible(&port->open_wait);
	}
	port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&port->close_wait);
out:	restore_flags(flags);
}

static int rc_write(struct tty_struct * tty, int from_user, 
		    const unsigned char *buf, int count)
{
	struct riscom_port *port = (struct riscom_port *)tty->driver_data;
	struct riscom_board *bp;
	int c, total = 0;
	unsigned long flags;
				
	if (rc_paranoia_check(port, tty->name, "rc_write"))
		return 0;
	
	bp = port_Board(port);

	if (!tty || !port->xmit_buf || !tmp_buf)
		return 0;

	save_flags(flags);
	if (from_user) {
		down(&tmp_buf_sem);
		while (1) {
			cli();		
			c = min_t(int, count, min(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
						  SERIAL_XMIT_SIZE - port->xmit_head));
			if (c <= 0)
				break;

			c -= copy_from_user(tmp_buf, buf, c);
			if (!c) {
				if (!total)
					total = -EFAULT;
				break;
			}

			cli();
			c = min_t(int, c, min(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
					 SERIAL_XMIT_SIZE - port->xmit_head));
			memcpy(port->xmit_buf + port->xmit_head, tmp_buf, c);
			port->xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
			port->xmit_cnt += c;
			restore_flags(flags);

			buf += c;
			count -= c;
			total += c;
		}
		up(&tmp_buf_sem);
	} else {
		while (1) {
			cli();		
			c = min_t(int, count, min(SERIAL_XMIT_SIZE - port->xmit_cnt - 1,
						  SERIAL_XMIT_SIZE - port->xmit_head));
			if (c <= 0) {
				restore_flags(flags);
				break;
			}

			memcpy(port->xmit_buf + port->xmit_head, buf, c);
			port->xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
			port->xmit_cnt += c;
			restore_flags(flags);

			buf += c;
			count -= c;
			total += c;
		}
	}

	cli();
	if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
	    !(port->IER & IER_TXRDY)) {
		port->IER |= IER_TXRDY;
		rc_out(bp, CD180_CAR, port_No(port));
		rc_out(bp, CD180_IER, port->IER);
	}
	restore_flags(flags);

	return total;
}

static void rc_put_char(struct tty_struct * tty, unsigned char ch)
{
	struct riscom_port *port = (struct riscom_port *)tty->driver_data;
	unsigned long flags;

	if (rc_paranoia_check(port, tty->name, "rc_put_char"))
		return;