ser_a2232.c

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	status->Command = a2232_cmd | A2232CMD_Open |  A2232CMD_Enable;
	status->SoftFlow = softflow;
	status->OutDisable = 0;
	status->Setup = -1;

	local_irq_restore(flags);
	return 0;
}

static int  a2232_chars_in_buffer(void *ptr)
{
	struct a2232_port *port;
	volatile struct a2232status *status; 
	unsigned char ret; /* we need modulo-256 arithmetics */
	port = ptr;
	status = a2232stat(port->which_a2232, port->which_port_on_a2232);
#if A2232_IOBUFLEN != 256
#error "Re-Implement a2232_chars_in_buffer()!"
#endif
	ret = (status->OutHead - status->OutTail);
	return ret;
}

static void a2232_close(void *ptr)
{
	a2232_disable_tx_interrupts(ptr);
	a2232_disable_rx_interrupts(ptr);
	/* see the comment in a2232_shutdown_port above. */
}

static void a2232_hungup(void *ptr)
{
	a2232_close(ptr);
}
/*** END   OF REAL_DRIVER FUNCTIONS ***/

/*** BEGIN  FUNCTIONS EXPECTED BY TTY DRIVER STRUCTS ***/
static int a2232_ioctl(	struct tty_struct *tty, struct file *file,
			unsigned int cmd, unsigned long arg)
{
	return -ENOIOCTLCMD;
}

static void a2232_throttle(struct tty_struct *tty)
{
/* Throttle: System cannot take another chars: Drop RTS or
             send the STOP char or whatever.
   The A2232 firmware does RTS/CTS anyway, and XON/XOFF
   if switched on. So the only thing we can do at this
   layer here is not taking any characters out of the
   A2232 buffer any more. */
	struct a2232_port *port = (struct a2232_port *) tty->driver_data;
	port->throttle_input = -1;
}

static void a2232_unthrottle(struct tty_struct *tty)
{
/* Unthrottle: dual to "throttle()" above. */
	struct a2232_port *port = (struct a2232_port *) tty->driver_data;
	port->throttle_input = 0;
}

static int  a2232_open(struct tty_struct * tty, struct file * filp)
{
/* More or less stolen from other drivers. */
	int line;
	int retval;
	struct a2232_port *port;

	line = tty->index;
	port = &a2232_ports[line];
	
	tty->driver_data = port;
	port->gs.tty = tty;
	port->gs.count++;
	retval = gs_init_port(&port->gs);
	if (retval) {
		port->gs.count--;
		return retval;
	}
	port->gs.flags |= GS_ACTIVE;
	retval = gs_block_til_ready(port, filp);

	if (retval) {
		port->gs.count--;
		return retval;
	}

	a2232_enable_rx_interrupts(port);
	
	return 0;
}
/*** END OF FUNCTIONS EXPECTED BY TTY DRIVER STRUCTS ***/

static irqreturn_t a2232_vbl_inter(int irq, void *data)
{
#if A2232_IOBUFLEN != 256
#error "Re-Implement a2232_vbl_inter()!"
#endif

struct a2232_port *port;
volatile struct a2232memory *mem;
volatile struct a2232status *status;
unsigned char newhead;
unsigned char bufpos; /* Must be unsigned char. We need the modulo-256 arithmetics */
unsigned char ncd, ocd, ccd; /* names consistent with the NetBSD driver */
volatile u_char *ibuf, *cbuf, *obuf;
int ch, err, n, p;
	for (n = 0; n < nr_a2232; n++){		/* for every completely initialized A2232 board */
		mem = a2232mem(n);
		for (p = 0; p < NUMLINES; p++){	/* for every port on this board */
			err = 0;
			port = &a2232_ports[n*NUMLINES+p];
			if ( port->gs.flags & GS_ACTIVE ){ /* if the port is used */

				status = a2232stat(n,p);

				if (!port->disable_rx && !port->throttle_input){ /* If input is not disabled */
					newhead = status->InHead;               /* 65EC02 write pointer */
					bufpos = status->InTail;

					/* check for input for this port */
					if (newhead != bufpos) {
						/* buffer for input chars/events */
						ibuf = mem->InBuf[p];
 
						/* data types of bytes in ibuf */
						cbuf = mem->InCtl[p];
 
						/* do for all chars */
						while (bufpos != newhead) {
							/* which type of input data? */
							switch (cbuf[bufpos]) {
								/* switch on input event (CD, BREAK, etc.) */
							case A2232INCTL_EVENT:
								switch (ibuf[bufpos++]) {
								case A2232EVENT_Break:
									/* TODO: Handle BREAK signal */
									break;
									/*	A2232EVENT_CarrierOn and A2232EVENT_CarrierOff are
										handled in a separate queue and should not occur here. */
								case A2232EVENT_Sync:
									printk("A2232: 65EC02 software sent SYNC event, don't know what to do. Ignoring.");
									break;
								default:
									printk("A2232: 65EC02 software broken, unknown event type %d occurred.\n",ibuf[bufpos-1]);
								} /* event type switch */
								break;
 							case A2232INCTL_CHAR:
								/* Receive incoming char */
								a2232_receive_char(port, ibuf[bufpos], err);
								bufpos++;
								break;
 							default:
								printk("A2232: 65EC02 software broken, unknown data type %d occurred.\n",cbuf[bufpos]);
								bufpos++;
							} /* switch on input data type */
						} /* while there's something in the buffer */

						status->InTail = bufpos;            /* tell 65EC02 what we've read */
						
					} /* if there was something in the buffer */                          
				} /* If input is not disabled */

				/* Now check if there's something to output */
				obuf = mem->OutBuf[p];
				bufpos = status->OutHead;
				while ( (port->gs.xmit_cnt > 0)		&&
					(!port->gs.tty->stopped)	&&
					(!port->gs.tty->hw_stopped) ){	/* While there are chars to transmit */
					if (((bufpos+1) & A2232_IOBUFLENMASK) != status->OutTail) { /* If the A2232 buffer is not full */
						ch = port->gs.xmit_buf[port->gs.xmit_tail];					/* get the next char to transmit */
						port->gs.xmit_tail = (port->gs.xmit_tail+1) & (SERIAL_XMIT_SIZE-1); /* modulo-addition for the gs.xmit_buf ring-buffer */
						obuf[bufpos++] = ch;																/* put it into the A2232 buffer */
						port->gs.xmit_cnt--;
					}
					else{																									/* If A2232 the buffer is full */
						break;																							/* simply stop filling it. */
					}													
				}					
				status->OutHead = bufpos;
					
				/* WakeUp if output buffer runs low */
				if ((port->gs.xmit_cnt <= port->gs.wakeup_chars) && port->gs.tty) {
					tty_wakeup(port->gs.tty);
				}
			} // if the port is used
		} // for every port on the board
			
		/* Now check the CD message queue */
		newhead = mem->Common.CDHead;
		bufpos = mem->Common.CDTail;
		if (newhead != bufpos){				/* There are CD events in queue */
			ocd = mem->Common.CDStatus; 		/* get old status bits */
			while (newhead != bufpos){		/* read all events */
				ncd = mem->CDBuf[bufpos++]; 	/* get one event */
				ccd = ncd ^ ocd; 		/* mask of changed lines */
				ocd = ncd; 			/* save new status bits */
				for(p=0; p < NUMLINES; p++){	/* for all ports */
					if (ccd & 1){		/* this one changed */

						struct a2232_port *port = &a2232_ports[n*7+p];
						port->cd_status = !(ncd & 1); /* ncd&1 <=> CD is now off */

						if (!(port->gs.flags & ASYNC_CHECK_CD))
							;	/* Don't report DCD changes */
						else if (port->cd_status) { // if DCD on: DCD went UP!
							
							/* Are we blocking in open?*/
							wake_up_interruptible(&port->gs.open_wait);
						}
						else { // if DCD off: DCD went DOWN!
							if (port->gs.tty)
								tty_hangup (port->gs.tty);
						}
						
					} // if CD changed for this port
					ccd >>= 1;
					ncd >>= 1;									/* Shift bits for next line */
				} // for every port
			} // while CD events in queue
			mem->Common.CDStatus = ocd; /* save new status */
			mem->Common.CDTail = bufpos; /* remove events */
		} // if events in CD queue
		
	} // for every completely initialized A2232 board
	return IRQ_HANDLED;
}

static void a2232_init_portstructs(void)
{
	struct a2232_port *port;
	int i;

	for (i = 0; i < MAX_A2232_BOARDS*NUMLINES; i++) {
		port = a2232_ports + i;
		port->which_a2232 = i/NUMLINES;
		port->which_port_on_a2232 = i%NUMLINES;
		port->disable_rx = port->throttle_input = port->cd_status = 0;
		port->gs.magic = A2232_MAGIC;
		port->gs.close_delay = HZ/2;
		port->gs.closing_wait = 30 * HZ;
		port->gs.rd = &a2232_real_driver;
#ifdef NEW_WRITE_LOCKING
		init_MUTEX(&(port->gs.port_write_mutex));
#endif
		init_waitqueue_head(&port->gs.open_wait);
		init_waitqueue_head(&port->gs.close_wait);
	}
}

static const struct tty_operations a2232_ops = {
	.open = a2232_open,
	.close = gs_close,
	.write = gs_write,
	.put_char = gs_put_char,
	.flush_chars = gs_flush_chars,
	.write_room = gs_write_room,
	.chars_in_buffer = gs_chars_in_buffer,
	.flush_buffer = gs_flush_buffer,
	.ioctl = a2232_ioctl,
	.throttle = a2232_throttle,
	.unthrottle = a2232_unthrottle,
	.set_termios = gs_set_termios,
	.stop = gs_stop,
	.start = gs_start,
	.hangup = gs_hangup,
};

static int a2232_init_drivers(void)
{
	int error;

	a2232_driver = alloc_tty_driver(NUMLINES * nr_a2232);
	if (!a2232_driver)
		return -ENOMEM;
	a2232_driver->owner = THIS_MODULE;
	a2232_driver->driver_name = "commodore_a2232";
	a2232_driver->name = "ttyY";
	a2232_driver->major = A2232_NORMAL_MAJOR;
	a2232_driver->type = TTY_DRIVER_TYPE_SERIAL;
	a2232_driver->subtype = SERIAL_TYPE_NORMAL;
	a2232_driver->init_termios = tty_std_termios;
	a2232_driver->init_termios.c_cflag =
		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	a2232_driver->init_termios.c_ispeed = 9600;
	a2232_driver->init_termios.c_ospeed = 9600;
	a2232_driver->flags = TTY_DRIVER_REAL_RAW;
	tty_set_operations(a2232_driver, &a2232_ops);
	if ((error = tty_register_driver(a2232_driver))) {
		printk(KERN_ERR "A2232: Couldn't register A2232 driver, error = %d\n",
		       error);
		put_tty_driver(a2232_driver);
		return 1;
	}
	return 0;
}

static int __init a2232board_init(void)
{
	struct zorro_dev *z;

	unsigned int boardaddr;
	int bcount;
	short start;
	u_char *from;
	volatile u_char *to;
	volatile struct a2232memory *mem;

#ifdef CONFIG_SMP
	return -ENODEV;	/* This driver is not SMP aware. Is there an SMP ZorroII-bus-machine? */
#endif

	if (!MACH_IS_AMIGA){
		return -ENODEV;
	}

	printk("Commodore A2232 driver initializing.\n"); /* Say that we're alive. */

	z = NULL;
	nr_a2232 = 0;
	while ( (z = zorro_find_device(ZORRO_WILDCARD, z)) ){
		if (	(z->id != ZORRO_PROD_CBM_A2232_PROTOTYPE) && 
			(z->id != ZORRO_PROD_CBM_A2232)	){
			continue;	// The board found was no A2232
		}
		if (!zorro_request_device(z,"A2232 driver"))
			continue;

		printk("Commodore A2232 found (#%d).\n",nr_a2232);

		zd_a2232[nr_a2232] = z;

		boardaddr = ZTWO_VADDR( z->resource.start );
		printk("Board is located at address 0x%x, size is 0x%x.\n", boardaddr, (unsigned int) ((z->resource.end+1) - (z->resource.start)));

		mem = (volatile struct a2232memory *) boardaddr;

		(void) mem->Enable6502Reset;   /* copy the code across to the board */
		to = (u_char *)mem;  from = a2232_65EC02code; bcount = sizeof(a2232_65EC02code) - 2;
		start = *(short *)from;
		from += sizeof(start);
		to += start;
		while(bcount--) *to++ = *from++;
		printk("65EC02 software uploaded to the A2232 memory.\n");
  
		mem->Common.Crystal = A2232_UNKNOWN;  /* use automatic speed check */
  
		/* start 6502 running */
		(void) mem->ResetBoard;
		printk("A2232's 65EC02 CPU up and running.\n");
  
		/* wait until speed detector has finished */
		for (bcount = 0; bcount < 2000; bcount++) {
			udelay(1000);
			if (mem->Common.Crystal)
				break;
		}
		printk((mem->Common.Crystal?"A2232 oscillator crystal detected by 65EC02 software: ":"65EC02 software could not determine A2232 oscillator crystal: "));
		switch (mem->Common.Crystal){
		case A2232_UNKNOWN:
			printk("Unknown crystal.\n");
			break;
 		case A2232_NORMAL:
			printk ("Normal crystal.\n");
			break;
		case A2232_TURBO:
			printk ("Turbo crystal.\n");
			break;
		default:
			printk ("0x%x. Huh?\n",mem->Common.Crystal);
		}

		nr_a2232++;

	}	

	printk("Total: %d A2232 boards initialized.\n", nr_a2232); /* Some status report if no card was found */

	a2232_init_portstructs();

	/*
		a2232_init_drivers also registers the drivers. Must be here because all boards
		have to be detected first.
	*/
	if (a2232_init_drivers()) return -ENODEV; // maybe we should use a different -Exxx?

	request_irq(IRQ_AMIGA_VERTB, a2232_vbl_inter, 0, "A2232 serial VBL", a2232_driver_ID);
	return 0;
}

static void __exit a2232board_exit(void)
{
	int i;

	for (i = 0; i < nr_a2232; i++) {
		zorro_release_device(zd_a2232[i]);
	}

	tty_unregister_driver(a2232_driver);
	put_tty_driver(a2232_driver);
	free_irq(IRQ_AMIGA_VERTB, a2232_driver_ID);
}

module_init(a2232board_init);
module_exit(a2232board_exit);

MODULE_AUTHOR("Enver Haase");
MODULE_DESCRIPTION("Amiga A2232 multi-serial board driver");
MODULE_LICENSE("GPL");