riscom8.c

powerpc内核mpc8241linux系统下char驱动程序

		port->IER &= ~IER_TXRDY;
		rc_out(bp, CD180_IER, port->IER);
		return;
	}
	
	if (port->break_length)  {
		if (port->break_length > 0)  {
			if (port->COR2 & COR2_ETC)  {
				rc_out(bp, CD180_TDR, CD180_C_ESC);
				rc_out(bp, CD180_TDR, CD180_C_SBRK);
				port->COR2 &= ~COR2_ETC;
			}
			count = MIN(port->break_length, 0xff);
			rc_out(bp, CD180_TDR, CD180_C_ESC);
			rc_out(bp, CD180_TDR, CD180_C_DELAY);
			rc_out(bp, CD180_TDR, count);
			if (!(port->break_length -= count))
				port->break_length--;
		} else  {
			rc_out(bp, CD180_TDR, CD180_C_ESC);
			rc_out(bp, CD180_TDR, CD180_C_EBRK);
			rc_out(bp, CD180_COR2, port->COR2);
			rc_wait_CCR(bp);
			rc_out(bp, CD180_CCR, CCR_CORCHG2);
			port->break_length = 0;
		}
		return;
	}
	
	count = CD180_NFIFO;
	do {
		rc_out(bp, CD180_TDR, port->xmit_buf[port->xmit_tail++]);
		port->xmit_tail = port->xmit_tail & (SERIAL_XMIT_SIZE-1);
		if (--port->xmit_cnt <= 0)
			break;
	} while (--count > 0);
	
	if (port->xmit_cnt <= 0)  {
		rc_out(bp, CD180_CAR, port_No(port));
		port->IER &= ~IER_TXRDY;
		rc_out(bp, CD180_IER, port->IER);
	}
	if (port->xmit_cnt <= port->wakeup_chars)
		rc_mark_event(port, RS_EVENT_WRITE_WAKEUP);
}

extern inline void rc_check_modem(struct riscom_board const * bp)
{
	struct riscom_port *port;
	struct tty_struct *tty;
	unsigned char mcr;
	
	if (!(port = rc_get_port(bp, "Modem")))
		return;
	
	tty = port->tty;
	
	mcr = rc_in(bp, CD180_MCR);
	if (mcr & MCR_CDCHG)  {
		if (rc_in(bp, CD180_MSVR) & MSVR_CD) 
			wake_up_interruptible(&port->open_wait);
		else if (!((port->flags & ASYNC_CALLOUT_ACTIVE) &&
			   (port->flags & ASYNC_CALLOUT_NOHUP)))
			queue_task(&port->tqueue_hangup,  &tq_scheduler);      
	}
	
#ifdef RISCOM_BRAIN_DAMAGED_CTS
	if (mcr & MCR_CTSCHG)  {
		if (rc_in(bp, CD180_MSVR) & MSVR_CTS)  {
			tty->hw_stopped = 0;
			port->IER |= IER_TXRDY;
			if (port->xmit_cnt <= port->wakeup_chars)
				rc_mark_event(port, RS_EVENT_WRITE_WAKEUP);
		} else  {
			tty->hw_stopped = 1;
			port->IER &= ~IER_TXRDY;
		}
		rc_out(bp, CD180_IER, port->IER);
	}
	if (mcr & MCR_DSRCHG)  {
		if (rc_in(bp, CD180_MSVR) & MSVR_DSR)  {
			tty->hw_stopped = 0;
			port->IER |= IER_TXRDY;
			if (port->xmit_cnt <= port->wakeup_chars)
				rc_mark_event(port, RS_EVENT_WRITE_WAKEUP);
		} else  {
			tty->hw_stopped = 1;
			port->IER &= ~IER_TXRDY;
		}
		rc_out(bp, CD180_IER, port->IER);
	}
#endif /* RISCOM_BRAIN_DAMAGED_CTS */
	
	/* Clear change bits */
	rc_out(bp, CD180_MCR, 0);
}

/* The main interrupt processing routine */
static void rc_interrupt(int irq, void * dev_id, struct pt_regs * regs)
{
	unsigned char status;
	unsigned char ack;
	struct riscom_board *bp;
	unsigned long loop = 0;
	
	bp = IRQ_to_board[irq];
	
	if (!bp || !(bp->flags & RC_BOARD_ACTIVE))  {
		return;
	}
	
	while ((++loop < 16) && ((status = ~(rc_in(bp, RC_BSR))) &
				 (RC_BSR_TOUT | RC_BSR_TINT |
				  RC_BSR_MINT | RC_BSR_RINT))) {
	
		if (status & RC_BSR_TOUT) 
			printk("rc%d: Got timeout. Hardware error ?\n", board_No(bp));
		
		else if (status & RC_BSR_RINT) {
			ack = rc_in(bp, RC_ACK_RINT);
		
			if (ack == (RC_ID | GIVR_IT_RCV))
				rc_receive(bp);
			else if (ack == (RC_ID | GIVR_IT_REXC))
				rc_receive_exc(bp);
			else
				printk("rc%d: Bad receive ack 0x%02x.\n",
				       board_No(bp), ack);
		
		} else if (status & RC_BSR_TINT) {
			ack = rc_in(bp, RC_ACK_TINT);
		
			if (ack == (RC_ID | GIVR_IT_TX))
				rc_transmit(bp);
			else
				printk("rc%d: Bad transmit ack 0x%02x.\n",
				       board_No(bp), ack);
		
		} else /* if (status & RC_BSR_MINT) */ {
			ack = rc_in(bp, RC_ACK_MINT);
		
			if (ack == (RC_ID | GIVR_IT_MODEM)) 
				rc_check_modem(bp);
			else
				printk("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    */
	}
}

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

/* Called with disabled interrupts */
extern 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;
	
	MOD_INC_USE_COUNT;
	return 0;
}

/* Called with disabled interrupts */
extern 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 */
	
	MOD_DEC_USE_COUNT;
}

/*
 * 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_free_page() */
		unsigned long tmp;
		
		if (!(tmp = get_free_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("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("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("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)
{
	struct wait_queue wait = { current, NULL };
	struct riscom_board *bp = port_Board(port);
	int    retval;
	int    do_clocal = 0;
	int    CD;