sunsab.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,166 行 · 第 1/2 页

	spin_unlock_irqrestore(&up->port.lock, flags);

	return 0;
}

/* port->lock is not held.  */
static void sunsab_shutdown(struct uart_port *port)
{
	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
	unsigned long flags;
	unsigned char tmp;

	spin_lock_irqsave(&up->port.lock, flags);

	/* Disable Interrupts */
	up->interrupt_mask0 = 0xff;
	writeb(up->interrupt_mask0, &up->regs->w.imr0);
	up->interrupt_mask1 = 0xff;
	writeb(up->interrupt_mask1, &up->regs->w.imr1);

	/* Disable break condition */
	tmp = readb(&up->regs->rw.dafo);
	tmp &= ~SAB82532_DAFO_XBRK;
	writeb(tmp, &up->regs->rw.dafo);

	/* Disable Receiver */	
	tmp = readb(&up->regs->rw.mode);
	tmp &= ~SAB82532_MODE_RAC;
	writeb(tmp, &up->regs->rw.mode);

	/*
	 * XXX FIXME
	 *
	 * If the chip is powered down here the system hangs/crashes during
	 * reboot or shutdown.  This needs to be investigated further,
	 * similar behaviour occurs in 2.4 when the driver is configured
	 * as a module only.  One hint may be that data is sometimes
	 * transmitted at 9600 baud during shutdown (regardless of the
	 * speed the chip was configured for when the port was open).
	 */
#if 0
	/* Power Down */	
	tmp = readb(&up->regs->rw.ccr0);
	tmp &= ~SAB82532_CCR0_PU;
	writeb(tmp, &up->regs->rw.ccr0);
#endif

	spin_unlock_irqrestore(&up->port.lock, flags);
}

/*
 * This is used to figure out the divisor speeds.
 *
 * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
 *
 * with               0 <= N < 64 and 0 <= M < 16
 */

static void calc_ebrg(int baud, int *n_ret, int *m_ret)
{
	int	n, m;

	if (baud == 0) {
		*n_ret = 0;
		*m_ret = 0;
		return;
	}
     
	/*
	 * We scale numbers by 10 so that we get better accuracy
	 * without having to use floating point.  Here we increment m
	 * until n is within the valid range.
	 */
	n = (SAB_BASE_BAUD * 10) / baud;
	m = 0;
	while (n >= 640) {
		n = n / 2;
		m++;
	}
	n = (n+5) / 10;
	/*
	 * We try very hard to avoid speeds with M == 0 since they may
	 * not work correctly for XTAL frequences above 10 MHz.
	 */
	if ((m == 0) && ((n & 1) == 0)) {
		n = n / 2;
		m++;
	}
	*n_ret = n - 1;
	*m_ret = m;
}

/* Internal routine, port->lock is held and local interrupts are disabled.  */
static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
				  unsigned int iflag, int baud)
{
	unsigned int ebrg;
	unsigned char dafo;
	int bits, n, m;

	/* Byte size and parity */
	switch (cflag & CSIZE) {
	      case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
	      case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
	      case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
	      case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
	      /* Never happens, but GCC is too dumb to figure it out */
	      default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
	}

	if (cflag & CSTOPB) {
		dafo |= SAB82532_DAFO_STOP;
		bits++;
	}

	if (cflag & PARENB) {
		dafo |= SAB82532_DAFO_PARE;
		bits++;
	}

	if (cflag & PARODD) {
		dafo |= SAB82532_DAFO_PAR_ODD;
	} else {
		dafo |= SAB82532_DAFO_PAR_EVEN;
	}

	calc_ebrg(baud, &n, &m);

	ebrg = n | (m << 6);

	up->tec_timeout = (10 * 1000000) / baud;
	up->cec_timeout = up->tec_timeout >> 2;

	/* CTS flow control flags */
	/* We encode read_status_mask and ignore_status_mask like so:
	 *
	 * ---------------------
	 * | ... | ISR1 | ISR0 |
	 * ---------------------
	 *  ..    15   8 7    0
	 */

	up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
				     SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
				     SAB82532_ISR0_CDSC);
	up->port.read_status_mask |= (SAB82532_ISR1_CSC |
				      SAB82532_ISR1_ALLS |
				      SAB82532_ISR1_XPR) << 8;
	if (iflag & INPCK)
		up->port.read_status_mask |= (SAB82532_ISR0_PERR |
					      SAB82532_ISR0_FERR);
	if (iflag & (BRKINT | PARMRK))
		up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);

	/*
	 * Characteres to ignore
	 */
	up->port.ignore_status_mask = 0;
	if (iflag & IGNPAR)
		up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
						SAB82532_ISR0_FERR);
	if (iflag & IGNBRK) {
		up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
		/*
		 * If we're ignoring parity and break indicators,
		 * ignore overruns too (for real raw support).
		 */
		if (iflag & IGNPAR)
			up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
	}

	/*
	 * ignore all characters if CREAD is not set
	 */
	if ((cflag & CREAD) == 0)
		up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
						SAB82532_ISR0_TCD);

	/* Now bang the new settings into the chip.  */
	sunsab_cec_wait(up);
	sunsab_tec_wait(up);
	writeb(dafo, &up->regs->w.dafo);
	writeb(ebrg & 0xff, &up->regs->w.bgr);
	writeb((readb(&up->regs->rw.ccr2) & ~0xc0) | ((ebrg >> 2) & 0xc0),
	       &up->regs->rw.ccr2);

	writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_RAC, &up->regs->rw.mode);

}

/* port->lock is not held.  */
static void sunsab_set_termios(struct uart_port *port, struct termios *termios,
			       struct termios *old)
{
	struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
	unsigned long flags;
	int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);

	spin_lock_irqsave(&up->port.lock, flags);
	sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud);
	spin_unlock_irqrestore(&up->port.lock, flags);
}

static const char *sunsab_type(struct uart_port *port)
{
	struct uart_sunsab_port *up = (void *)port;
	static char buf[36];
	
	sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
	return buf;
}

static void sunsab_release_port(struct uart_port *port)
{
}

static int sunsab_request_port(struct uart_port *port)
{
	return 0;
}

static void sunsab_config_port(struct uart_port *port, int flags)
{
}

static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
{
	return -EINVAL;
}

static struct uart_ops sunsab_pops = {
	.tx_empty	= sunsab_tx_empty,
	.set_mctrl	= sunsab_set_mctrl,
	.get_mctrl	= sunsab_get_mctrl,
	.stop_tx	= sunsab_stop_tx,
	.start_tx	= sunsab_start_tx,
	.send_xchar	= sunsab_send_xchar,
	.stop_rx	= sunsab_stop_rx,
	.enable_ms	= sunsab_enable_ms,
	.break_ctl	= sunsab_break_ctl,
	.startup	= sunsab_startup,
	.shutdown	= sunsab_shutdown,
	.set_termios	= sunsab_set_termios,
	.type		= sunsab_type,
	.release_port	= sunsab_release_port,
	.request_port	= sunsab_request_port,
	.config_port	= sunsab_config_port,
	.verify_port	= sunsab_verify_port,
};

static struct uart_driver sunsab_reg = {
	.owner			= THIS_MODULE,
	.driver_name		= "serial",
	.devfs_name		= "tts/",
	.dev_name		= "ttyS",
	.major			= TTY_MAJOR,
};

static struct uart_sunsab_port *sunsab_ports;
static int num_channels;

#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE

static __inline__ void sunsab_console_putchar(struct uart_sunsab_port *up, char c)
{
	unsigned long flags;

	spin_lock_irqsave(&up->port.lock, flags);

	sunsab_tec_wait(up);
	writeb(c, &up->regs->w.tic);

	spin_unlock_irqrestore(&up->port.lock, flags);
}

static void sunsab_console_write(struct console *con, const char *s, unsigned n)
{
	struct uart_sunsab_port *up = &sunsab_ports[con->index];
	int i;

	for (i = 0; i < n; i++) {
		if (*s == '\n')
			sunsab_console_putchar(up, '\r');
		sunsab_console_putchar(up, *s++);
	}
	sunsab_tec_wait(up);
}

static int sunsab_console_setup(struct console *con, char *options)
{
	struct uart_sunsab_port *up = &sunsab_ports[con->index];
	unsigned long flags;
	int baud;

	printk("Console: ttyS%d (SAB82532)\n",
	       (sunsab_reg.minor - 64) + con->index);

	sunserial_console_termios(con);

	/* Firmware console speed is limited to 150-->38400 baud so
	 * this hackish cflag thing is OK.
	 */
	switch (con->cflag & CBAUD) {
	case B150: baud = 150; break;
	case B300: baud = 300; break;
	case B600: baud = 600; break;
	case B1200: baud = 1200; break;
	case B2400: baud = 2400; break;
	case B4800: baud = 4800; break;
	default: case B9600: baud = 9600; break;
	case B19200: baud = 19200; break;
	case B38400: baud = 38400; break;
	};

	/*
	 * Temporary fix.
	 */
	spin_lock_init(&up->port.lock);

	/*
	 * Initialize the hardware
	 */
	sunsab_startup(&up->port);

	spin_lock_irqsave(&up->port.lock, flags);

	/*
	 * Finally, enable interrupts
	 */
	up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
				SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
	writeb(up->interrupt_mask0, &up->regs->w.imr0);
	up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
				SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
				SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
				SAB82532_IMR1_XPR;
	writeb(up->interrupt_mask1, &up->regs->w.imr1);

	sunsab_convert_to_sab(up, con->cflag, 0, baud);
	sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);

	spin_unlock_irqrestore(&up->port.lock, flags);
	
	return 0;
}

static struct console sunsab_console = {
	.name	=	"ttyS",
	.write	=	sunsab_console_write,
	.device	=	uart_console_device,
	.setup	=	sunsab_console_setup,
	.flags	=	CON_PRINTBUFFER,
	.index	=	-1,
	.data	=	&sunsab_reg,
};
#define SUNSAB_CONSOLE	(&sunsab_console)

static void __init sunsab_console_init(void)
{
	int i;

	if (con_is_present())
		return;

	for (i = 0; i < num_channels; i++) {
		int this_minor = sunsab_reg.minor + i;

		if ((this_minor - 64) == (serial_console - 1))
			break;
	}
	if (i == num_channels)
		return;

	sunsab_console.index = i;
	register_console(&sunsab_console);
}
#else
#define SUNSAB_CONSOLE		(NULL)
#define sunsab_console_init()	do { } while (0)
#endif

static void __init for_each_sab_edev(void (*callback)(struct linux_ebus_device *, void *), void *arg)
{
	struct linux_ebus *ebus;
	struct linux_ebus_device *edev = NULL;

	for_each_ebus(ebus) {
		for_each_ebusdev(edev, ebus) {
			if (!strcmp(edev->prom_name, "se")) {
				callback(edev, arg);
				continue;
			} else if (!strcmp(edev->prom_name, "serial")) {
				char compat[32];
				int clen;

				/* On RIO this can be an SE, check it.  We could
				 * just check ebus->is_rio, but this is more portable.
				 */
				clen = prom_getproperty(edev->prom_node, "compatible",
							compat, sizeof(compat));
				if (clen > 0) {
					if (strncmp(compat, "sab82532", 8) == 0) {
						callback(edev, arg);
						continue;
					}
				}
			}
		}
	}
}

static void __init sab_count_callback(struct linux_ebus_device *edev, void *arg)
{
	int *count_p = arg;

	(*count_p)++;
}

static void __init sab_attach_callback(struct linux_ebus_device *edev, void *arg)
{
	int *instance_p = arg;
	struct uart_sunsab_port *up;
	unsigned long regs, offset;
	int i;

	/* Note: ports are located in reverse order */
	regs = edev->resource[0].start;
	offset = sizeof(union sab82532_async_regs);
	for (i = 0; i < 2; i++) {
		up = &sunsab_ports[(*instance_p * 2) + 1 - i];

		memset(up, 0, sizeof(*up));
		up->regs = ioremap(regs + offset, sizeof(union sab82532_async_regs));
		up->port.irq = edev->irqs[0];
		up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
		up->port.mapbase = (unsigned long)up->regs;
		up->port.iotype = SERIAL_IO_MEM;

		writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);

		offset -= sizeof(union sab82532_async_regs);
	}
	
	(*instance_p)++;
}

static int __init probe_for_sabs(void)
{
	int this_sab = 0;

	/* Find device instances.  */
	for_each_sab_edev(&sab_count_callback, &this_sab);
	if (!this_sab)
		return -ENODEV;

	/* Allocate tables.  */
	sunsab_ports = kmalloc(sizeof(struct uart_sunsab_port) * this_sab * 2,
			       GFP_KERNEL);
	if (!sunsab_ports)
		return -ENOMEM;

	num_channels = this_sab * 2;

	this_sab = 0;
	for_each_sab_edev(&sab_attach_callback, &this_sab);
	return 0;
}

static void __init sunsab_init_hw(void)
{
	int i;

	for (i = 0; i < num_channels; i++) {
		struct uart_sunsab_port *up = &sunsab_ports[i];

		up->port.line = i;
		up->port.ops = &sunsab_pops;
		up->port.type = PORT_SUNSAB;
		up->port.uartclk = SAB_BASE_BAUD;

		up->type = readb(&up->regs->r.vstr) & 0x0f;
		writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
		writeb(0xff, &up->regs->w.pim);
		if (up->port.line == 0) {
			up->pvr_dsr_bit = (1 << 0);
			up->pvr_dtr_bit = (1 << 1);
		} else {
			up->pvr_dsr_bit = (1 << 3);
			up->pvr_dtr_bit = (1 << 2);
		}
		writeb((1 << 1) | (1 << 2) | (1 << 4), &up->regs->w.pvr);
		writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_FRTS,
		       &up->regs->rw.mode);
		writeb(readb(&up->regs->rw.mode) | SAB82532_MODE_RTS,
		       &up->regs->rw.mode);

		up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
		up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;

		if (!(up->port.line & 0x01)) {
			if (request_irq(up->port.irq, sunsab_interrupt,
			                SA_SHIRQ, "serial(sab82532)", up)) {
				printk("sunsab%d: can't get IRQ %x\n",
				       i, up->port.irq);
				continue;
			}
		}
	}
}

static int __init sunsab_init(void)
{
	int ret = probe_for_sabs();
	int i;

	if (ret < 0)
		return ret;

	sunsab_init_hw();

	sunsab_reg.minor = sunserial_current_minor;
	sunsab_reg.nr = num_channels;
	sunsab_reg.cons = SUNSAB_CONSOLE;

	ret = uart_register_driver(&sunsab_reg);
	if (ret < 0) {
		int i;

		for (i = 0; i < num_channels; i++) {
			struct uart_sunsab_port *up = &sunsab_ports[i];

			if (!(up->port.line & 0x01))
				free_irq(up->port.irq, up);
			iounmap(up->regs);
		}
		kfree(sunsab_ports);
		sunsab_ports = NULL;

		return ret;
	}

	sunserial_current_minor += num_channels;
	
	for (i = 0; i < num_channels; i++) {
		struct uart_sunsab_port *up = &sunsab_ports[i];

		uart_add_one_port(&sunsab_reg, &up->port);
	}

	sunsab_console_init();

	return 0;
}

static void __exit sunsab_exit(void)
{
	int i;

	for (i = 0; i < num_channels; i++) {
		struct uart_sunsab_port *up = &sunsab_ports[i];

		uart_remove_one_port(&sunsab_reg, &up->port);

		if (!(up->port.line & 0x01))
			free_irq(up->port.irq, up);
		iounmap(up->regs);
	}

	sunserial_current_minor -= num_channels;
	uart_unregister_driver(&sunsab_reg);

	kfree(sunsab_ports);
	sunsab_ports = NULL;
}

module_init(sunsab_init);
module_exit(sunsab_exit);

MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
MODULE_LICENSE("GPL");