[deliverable/linux.git] / arch / ia64 / hp / sim / simserial.c

/*
 * Simulated Serial Driver (fake serial)
 *
 * This driver is mostly used for bringup purposes and will go away.
 * It has a strong dependency on the system console. All outputs
 * are rerouted to the same facility as the one used by printk which, in our
 * case means sys_sim.c console (goes via the simulator).
 *
 * Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co
 *	Stephane Eranian <eranian@hpl.hp.com>
 *	David Mosberger-Tang <davidm@hpl.hp.com>
 */

#include <linux/init.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/capability.h>
#include <linux/circ_buf.h>
#include <linux/console.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/serial.h>
#include <linux/sysrq.h>
#include <linux/uaccess.h>

#include <asm/hpsim.h>

#include "hpsim_ssc.h"

#undef SIMSERIAL_DEBUG	/* define this to get some debug information */

#define KEYBOARD_INTR	3	/* must match with simulator! */

#define NR_PORTS	1	/* only one port for now */

struct serial_state {
	struct tty_port port;
	struct circ_buf xmit;
	int irq;
	int x_char;
};

static struct serial_state rs_table[NR_PORTS];

struct tty_driver *hp_simserial_driver;

static struct console *console;

static void receive_chars(struct tty_struct *tty)
{
	unsigned char ch;
	static unsigned char seen_esc = 0;

	while ( (ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR)) ) {
		if (ch == 27 && seen_esc == 0) {
			seen_esc = 1;
			continue;
		} else if (seen_esc == 1 && ch == 'O') {
			seen_esc = 2;
			continue;
		} else if (seen_esc == 2) {
			if (ch == 'P') /* F1 */
				show_state();
#ifdef CONFIG_MAGIC_SYSRQ
			if (ch == 'S') { /* F4 */
				do {
					ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR);
				} while (!ch);
				handle_sysrq(ch);
			}
#endif
			seen_esc = 0;
			continue;
		}
		seen_esc = 0;

		if (tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0)
			break;
	}
	tty_flip_buffer_push(tty);
}

/*
 * This is the serial driver's interrupt routine for a single port
 */
static irqreturn_t rs_interrupt_single(int irq, void *dev_id)
{
	struct serial_state *info = dev_id;
	struct tty_struct *tty = tty_port_tty_get(&info->port);

	if (!tty) {
		printk(KERN_INFO "%s: tty=0 problem\n", __func__);
		return IRQ_NONE;
	}
	/*
	 * pretty simple in our case, because we only get interrupts
	 * on inbound traffic
	 */
	receive_chars(tty);
	tty_kref_put(tty);
	return IRQ_HANDLED;
}

/*
 * -------------------------------------------------------------------
 * Here ends the serial interrupt routines.
 * -------------------------------------------------------------------
 */

static int rs_put_char(struct tty_struct *tty, unsigned char ch)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (!info->xmit.buf)
		return 0;

	local_irq_save(flags);
	if (CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) == 0) {
		local_irq_restore(flags);
		return 0;
	}
	info->xmit.buf[info->xmit.head] = ch;
	info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
	local_irq_restore(flags);
	return 1;
}

static void transmit_chars(struct tty_struct *tty, struct serial_state *info,
		int *intr_done)
{
	int count;
	unsigned long flags;

	local_irq_save(flags);

	if (info->x_char) {
		char c = info->x_char;

		console->write(console, &c, 1);

		info->x_char = 0;

		goto out;
	}

	if (info->xmit.head == info->xmit.tail || tty->stopped ||
			tty->hw_stopped) {
#ifdef SIMSERIAL_DEBUG
		printk("transmit_chars: head=%d, tail=%d, stopped=%d\n",
		       info->xmit.head, info->xmit.tail, tty->stopped);
#endif
		goto out;
	}
	/*
	 * We removed the loop and try to do it in to chunks. We need
	 * 2 operations maximum because it's a ring buffer.
	 *
	 * First from current to tail if possible.
	 * Then from the beginning of the buffer until necessary
	 */

	count = min(CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE),
		    SERIAL_XMIT_SIZE - info->xmit.tail);
	console->write(console, info->xmit.buf+info->xmit.tail, count);

	info->xmit.tail = (info->xmit.tail+count) & (SERIAL_XMIT_SIZE-1);

	/*
	 * We have more at the beginning of the buffer
	 */
	count = CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
	if (count) {
		console->write(console, info->xmit.buf, count);
		info->xmit.tail += count;
	}
out:
	local_irq_restore(flags);
}

static void rs_flush_chars(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	if (info->xmit.head == info->xmit.tail || tty->stopped ||
			tty->hw_stopped || !info->xmit.buf)
		return;

	transmit_chars(tty, info, NULL);
}

static int rs_write(struct tty_struct * tty,
		    const unsigned char *buf, int count)
{
	struct serial_state *info = tty->driver_data;
	int	c, ret = 0;
	unsigned long flags;

	if (!info->xmit.buf)
		return 0;

	local_irq_save(flags);
	while (1) {
		c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
		if (count < c)
			c = count;
		if (c <= 0) {
			break;
		}
		memcpy(info->xmit.buf + info->xmit.head, buf, c);
		info->xmit.head = ((info->xmit.head + c) &
				   (SERIAL_XMIT_SIZE-1));
		buf += c;
		count -= c;
		ret += c;
	}
	local_irq_restore(flags);
	/*
	 * Hey, we transmit directly from here in our case
	 */
	if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) &&
			!tty->stopped && !tty->hw_stopped)
		transmit_chars(tty, info, NULL);

	return ret;
}

static int rs_write_room(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}

static int rs_chars_in_buffer(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}

static void rs_flush_buffer(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	local_irq_save(flags);
	info->xmit.head = info->xmit.tail = 0;
	local_irq_restore(flags);

	tty_wakeup(tty);
}

/*
 * This function is used to send a high-priority XON/XOFF character to
 * the device
 */
static void rs_send_xchar(struct tty_struct *tty, char ch)
{
	struct serial_state *info = tty->driver_data;

	info->x_char = ch;
	if (ch) {
		/*
		 * I guess we could call console->write() directly but
		 * let's do that for now.
		 */
		transmit_chars(tty, info, NULL);
	}
}

/*
 * ------------------------------------------------------------
 * rs_throttle()
 *
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static void rs_throttle(struct tty_struct * tty)
{
	if (I_IXOFF(tty))
		rs_send_xchar(tty, STOP_CHAR(tty));

	printk(KERN_INFO "simrs_throttle called\n");
}

static void rs_unthrottle(struct tty_struct * tty)
{
	struct serial_state *info = tty->driver_data;

	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			rs_send_xchar(tty, START_CHAR(tty));
	}
	printk(KERN_INFO "simrs_unthrottle called\n");
}

static int rs_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
{
	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
	    (cmd != TIOCMIWAIT)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
		    return -EIO;
	}

	switch (cmd) {
	case TIOCGSERIAL:
	case TIOCSSERIAL:
	case TIOCSERGSTRUCT:
	case TIOCMIWAIT:
		return 0;
	case TIOCSERCONFIG:
	case TIOCSERGETLSR: /* Get line status register */
		return -EINVAL;
	case TIOCSERGWILD:
	case TIOCSERSWILD:
		/* "setserial -W" is called in Debian boot */
		printk (KERN_INFO "TIOCSER?WILD ioctl obsolete, ignored.\n");
		return 0;
	}
	return -ENOIOCTLCMD;
}

#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))

static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
{
	/* Handle turning off CRTSCTS */
	if ((old_termios->c_cflag & CRTSCTS) &&
	    !(tty->termios.c_cflag & CRTSCTS)) {
		tty->hw_stopped = 0;
	}
}
/*
 * This routine will shutdown a serial port; interrupts are disabled, and
 * DTR is dropped if the hangup on close termio flag is on.
 */
static void shutdown(struct tty_port *port)
{
	struct serial_state *info = container_of(port, struct serial_state,
			port);
	unsigned long flags;

	local_irq_save(flags);
	if (info->irq)
		free_irq(info->irq, info);

	if (info->xmit.buf) {
		free_page((unsigned long) info->xmit.buf);
		info->xmit.buf = NULL;
	}
	local_irq_restore(flags);
}

static void rs_close(struct tty_struct *tty, struct file * filp)
{
	struct serial_state *info = tty->driver_data;

	tty_port_close(&info->port, tty, filp);
}

static void rs_hangup(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	rs_flush_buffer(tty);
	tty_port_hangup(&info->port);
}

static int activate(struct tty_port *port, struct tty_struct *tty)
{
	struct serial_state *state = container_of(port, struct serial_state,
			port);
	unsigned long flags, page;
	int retval = 0;

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

	local_irq_save(flags);

	if (state->xmit.buf)
		free_page(page);
	else
		state->xmit.buf = (unsigned char *) page;

	if (state->irq) {
		retval = request_irq(state->irq, rs_interrupt_single, 0,
				"simserial", state);
		if (retval)
			goto errout;
	}

	state->xmit.head = state->xmit.tail = 0;

	/*
	 * Set up the tty->alt_speed kludge
	 */
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
		tty->alt_speed = 57600;
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
		tty->alt_speed = 115200;
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
		tty->alt_speed = 230400;
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
		tty->alt_speed = 460800;

errout:
	local_irq_restore(flags);
	return retval;
}


/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int rs_open(struct tty_struct *tty, struct file * filp)
{
	struct serial_state *info = rs_table + tty->index;
	struct tty_port *port = &info->port;

	tty->driver_data = info;
	tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

	/*
	 * figure out which console to use (should be one already)
	 */
	console = console_drivers;
	while (console) {
		if ((console->flags & CON_ENABLED) && console->write) break;
		console = console->next;
	}

	return tty_port_open(port, tty, filp);
}

/*
 * /proc fs routines....
 */

static int rs_proc_show(struct seq_file *m, void *v)
{
	int i;

	seq_printf(m, "simserinfo:1.0\n");
	for (i = 0; i < NR_PORTS; i++)
		seq_printf(m, "%d: uart:16550 port:3F8 irq:%d\n",
		       i, rs_table[i].irq);
	return 0;
}

static int rs_proc_open(struct inode *inode, struct file *file)
{
	return single_open(file, rs_proc_show, NULL);
}

static const struct file_operations rs_proc_fops = {
	.owner		= THIS_MODULE,
	.open		= rs_proc_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct tty_operations hp_ops = {
	.open = rs_open,
	.close = rs_close,
	.write = rs_write,
	.put_char = rs_put_char,
	.flush_chars = rs_flush_chars,
	.write_room = rs_write_room,
	.chars_in_buffer = rs_chars_in_buffer,
	.flush_buffer = rs_flush_buffer,
	.ioctl = rs_ioctl,
	.throttle = rs_throttle,
	.unthrottle = rs_unthrottle,
	.send_xchar = rs_send_xchar,
	.set_termios = rs_set_termios,
	.hangup = rs_hangup,
	.proc_fops = &rs_proc_fops,
};

static const struct tty_port_operations hp_port_ops = {
	.activate = activate,
	.shutdown = shutdown,
};

static int __init simrs_init(void)
{
	struct serial_state *state;
	int retval;

	if (!ia64_platform_is("hpsim"))
		return -ENODEV;

	hp_simserial_driver = alloc_tty_driver(NR_PORTS);
	if (!hp_simserial_driver)
		return -ENOMEM;

	printk(KERN_INFO "SimSerial driver with no serial options enabled\n");

	/* Initialize the tty_driver structure */

	hp_simserial_driver->driver_name = "simserial";
	hp_simserial_driver->name = "ttyS";
	hp_simserial_driver->major = TTY_MAJOR;
	hp_simserial_driver->minor_start = 64;
	hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
	hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
	hp_simserial_driver->init_termios = tty_std_termios;
	hp_simserial_driver->init_termios.c_cflag =
		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
	tty_set_operations(hp_simserial_driver, &hp_ops);

	state = rs_table;
	tty_port_init(&state->port);
	state->port.ops = &hp_port_ops;
	state->port.close_delay = 0; /* XXX really 0? */

	retval = hpsim_get_irq(KEYBOARD_INTR);
	if (retval < 0) {
		printk(KERN_ERR "%s: out of interrupt vectors!\n",
				__func__);
		goto err_free_tty;
	}

	state->irq = retval;

	/* the port is imaginary */
	printk(KERN_INFO "ttyS0 at 0x03f8 (irq = %d) is a 16550\n", state->irq);

	tty_port_link_device(&state->port, hp_simserial_driver, 0);
	retval = tty_register_driver(hp_simserial_driver);
	if (retval) {
		printk(KERN_ERR "Couldn't register simserial driver\n");
		goto err_free_tty;
	}

	return 0;
err_free_tty:
	put_tty_driver(hp_simserial_driver);
	tty_port_destroy(&state->port);
	return retval;
}

#ifndef MODULE
__initcall(simrs_init);
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Simulated Serial Driver (fake serial)
	3	*
	4	* This driver is mostly used for bringup purposes and will go away.
	5	* It has a strong dependency on the system console. All outputs
	6	* are rerouted to the same facility as the one used by printk which, in our
adb636fe	7	* case means sys_sim.c console (goes via the simulator).
1da177e4 LT	8	*
	9	* Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co
	10	* Stephane Eranian <eranian@hpl.hp.com>
	11	* David Mosberger-Tang <davidm@hpl.hp.com>
1da177e4 LT	12	*/
1da177e4 LT	13
1da177e4 LT	14	#include <linux/init.h>
	15	#include <linux/errno.h>
	16	#include <linux/sched.h>
	17	#include <linux/tty.h>
	18	#include <linux/tty_flip.h>
	19	#include <linux/major.h>
	20	#include <linux/fcntl.h>
	21	#include <linux/mm.h>
bf54215e	22	#include <linux/seq_file.h>
1da177e4	23	#include <linux/slab.h>
a9415644	24	#include <linux/capability.h>
3c4782dc	25	#include <linux/circ_buf.h>
1da177e4	26	#include <linux/console.h>
8b916330	27	#include <linux/irq.h>
1da177e4 LT	28	#include <linux/module.h>
1da177e4 LT	29	#include <linux/serial.h>
819c67e6	30	#include <linux/sysrq.h>
8b916330	31	#include <linux/uaccess.h>
1da177e4	32
035cfe5a	33	#include <asm/hpsim.h>
1da177e4	34
035cfe5a JS	35	#include "hpsim_ssc.h"
035cfe5a JS	36
1da177e4 LT	37	#undef SIMSERIAL_DEBUG /* define this to get some debug information */
	38
	39	#define KEYBOARD_INTR 3 /* must match with simulator! */
	40
	41	#define NR_PORTS 1 /* only one port for now */
1da177e4	42
3c4782dc	43	struct serial_state {
7f32f8dd	44	struct tty_port port;
3c4782dc JS	45	struct circ_buf xmit;
	46	int irq;
	47	int x_char;
	48	};
	49
fd2d7a6e	50	static struct serial_state rs_table[NR_PORTS];
1da177e4 LT	51
	52	struct tty_driver *hp_simserial_driver;
	53
1da177e4 LT	54	static struct console *console;
1da177e4 LT	55
2fcd5caf	56	static void receive_chars(struct tty_struct *tty)
1da177e4 LT	57	{
	58	unsigned char ch;
	59	static unsigned char seen_esc = 0;
	60
	61	while ( (ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR)) ) {
f66279cd	62	if (ch == 27 && seen_esc == 0) {
1da177e4 LT	63	seen_esc = 1;
1da177e4 LT	64	continue;
f66279cd JS	65	} else if (seen_esc == 1 && ch == 'O') {
	66	seen_esc = 2;
	67	continue;
	68	} else if (seen_esc == 2) {
	69	if (ch == 'P') /* F1 */
	70	show_state();
819c67e6	71	#ifdef CONFIG_MAGIC_SYSRQ
f66279cd JS	72	if (ch == 'S') { /* F4 */
	73	do {
	74	ch = ia64_ssc(0, 0, 0, 0, SSC_GETCHAR);
	75	} while (!ch);
	76	handle_sysrq(ch);
1da177e4	77	}
f66279cd JS	78	#endif
	79	seen_esc = 0;
	80	continue;
1da177e4 LT	81	}
1da177e4 LT	82	seen_esc = 0;
1da177e4	83
d50f5c5c AS	84	if (tty_insert_flip_char(tty, ch, TTY_NORMAL) == 0)
d50f5c5c AS	85	break;
1da177e4 LT	86	}
	87	tty_flip_buffer_push(tty);
	88	}
	89
	90	/*
	91	* This is the serial driver's interrupt routine for a single port
	92	*/
5dcded1b	93	static irqreturn_t rs_interrupt_single(int irq, void *dev_id)
1da177e4	94	{
916b7656	95	struct serial_state *info = dev_id;
3a5c2423	96	struct tty_struct *tty = tty_port_tty_get(&info->port);
1da177e4	97
7f32f8dd	98	if (!tty) {
6e9ebcfa	99	printk(KERN_INFO "%s: tty=0 problem\n", __func__);
1da177e4 LT	100	return IRQ_NONE;
	101	}
	102	/*
	103	* pretty simple in our case, because we only get interrupts
	104	* on inbound traffic
	105	*/
7f32f8dd	106	receive_chars(tty);
3a5c2423	107	tty_kref_put(tty);
1da177e4 LT	108	return IRQ_HANDLED;
	109	}
	110
	111	/*
	112	* -------------------------------------------------------------------
	113	* Here ends the serial interrupt routines.
	114	* -------------------------------------------------------------------
	115	*/
	116
f34d7a5b	117	static int rs_put_char(struct tty_struct *tty, unsigned char ch)
1da177e4	118	{
916b7656	119	struct serial_state *info = tty->driver_data;
1da177e4 LT	120	unsigned long flags;
1da177e4 LT	121
6e9ebcfa	122	if (!info->xmit.buf)
f34d7a5b	123	return 0;
1da177e4 LT	124
	125	local_irq_save(flags);
	126	if (CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) == 0) {
	127	local_irq_restore(flags);
f34d7a5b	128	return 0;
1da177e4 LT	129	}
	130	info->xmit.buf[info->xmit.head] = ch;
	131	info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
	132	local_irq_restore(flags);
f34d7a5b	133	return 1;
1da177e4 LT	134	}
1da177e4 LT	135
5e99d545 JS	136	static void transmit_chars(struct tty_struct tty, struct serial_state info,
5e99d545 JS	137	int *intr_done)
1da177e4 LT	138	{
	139	int count;
	140	unsigned long flags;
	141
1da177e4 LT	142	local_irq_save(flags);
	143
	144	if (info->x_char) {
	145	char c = info->x_char;
	146
	147	console->write(console, &c, 1);
	148
1da177e4 LT	149	info->x_char = 0;
	150
	151	goto out;
	152	}
	153
5e99d545 JS	154	if (info->xmit.head == info->xmit.tail \|\| tty->stopped \|\|
5e99d545 JS	155	tty->hw_stopped) {
1da177e4 LT	156	#ifdef SIMSERIAL_DEBUG
1da177e4 LT	157	printk("transmit_chars: head=%d, tail=%d, stopped=%d\n",
5e99d545	158	info->xmit.head, info->xmit.tail, tty->stopped);
1da177e4 LT	159	#endif
	160	goto out;
	161	}
	162	/*
	163	* We removed the loop and try to do it in to chunks. We need
	164	* 2 operations maximum because it's a ring buffer.
	165	*
	166	* First from current to tail if possible.
	167	* Then from the beginning of the buffer until necessary
	168	*/
	169
	170	count = min(CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE),
	171	SERIAL_XMIT_SIZE - info->xmit.tail);
	172	console->write(console, info->xmit.buf+info->xmit.tail, count);
	173
	174	info->xmit.tail = (info->xmit.tail+count) & (SERIAL_XMIT_SIZE-1);
	175
	176	/*
	177	* We have more at the beginning of the buffer
	178	*/
	179	count = CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
	180	if (count) {
	181	console->write(console, info->xmit.buf, count);
	182	info->xmit.tail += count;
	183	}
	184	out:
	185	local_irq_restore(flags);
	186	}
	187
	188	static void rs_flush_chars(struct tty_struct *tty)
	189	{
916b7656	190	struct serial_state *info = tty->driver_data;
1da177e4	191
f66279cd JS	192	if (info->xmit.head == info->xmit.tail \|\| tty->stopped \|\|
f66279cd JS	193	tty->hw_stopped \|\| !info->xmit.buf)
1da177e4 LT	194	return;
1da177e4 LT	195
5e99d545	196	transmit_chars(tty, info, NULL);
1da177e4 LT	197	}
1da177e4 LT	198
1da177e4 LT	199	static int rs_write(struct tty_struct * tty,
	200	const unsigned char *buf, int count)
	201	{
916b7656	202	struct serial_state *info = tty->driver_data;
1da177e4	203	int c, ret = 0;
1da177e4 LT	204	unsigned long flags;
1da177e4 LT	205
6e9ebcfa	206	if (!info->xmit.buf)
d88405d4	207	return 0;
1da177e4 LT	208
	209	local_irq_save(flags);
	210	while (1) {
	211	c = CIRC_SPACE_TO_END(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
	212	if (count < c)
	213	c = count;
	214	if (c <= 0) {
	215	break;
	216	}
	217	memcpy(info->xmit.buf + info->xmit.head, buf, c);
	218	info->xmit.head = ((info->xmit.head + c) &
	219	(SERIAL_XMIT_SIZE-1));
	220	buf += c;
	221	count -= c;
	222	ret += c;
	223	}
	224	local_irq_restore(flags);
	225	/*
	226	* Hey, we transmit directly from here in our case
	227	*/
f66279cd JS	228	if (CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE) &&
f66279cd JS	229	!tty->stopped && !tty->hw_stopped)
5e99d545	230	transmit_chars(tty, info, NULL);
f66279cd	231
1da177e4 LT	232	return ret;
	233	}
	234
	235	static int rs_write_room(struct tty_struct *tty)
	236	{
916b7656	237	struct serial_state *info = tty->driver_data;
1da177e4 LT	238
	239	return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
	240	}
	241
	242	static int rs_chars_in_buffer(struct tty_struct *tty)
	243	{
916b7656	244	struct serial_state *info = tty->driver_data;
1da177e4 LT	245
	246	return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
	247	}
	248
	249	static void rs_flush_buffer(struct tty_struct *tty)
	250	{
916b7656	251	struct serial_state *info = tty->driver_data;
1da177e4 LT	252	unsigned long flags;
	253
	254	local_irq_save(flags);
	255	info->xmit.head = info->xmit.tail = 0;
	256	local_irq_restore(flags);
	257
15648f15	258	tty_wakeup(tty);
1da177e4 LT	259	}
	260
	261	/*
	262	* This function is used to send a high-priority XON/XOFF character to
	263	* the device
	264	*/
	265	static void rs_send_xchar(struct tty_struct *tty, char ch)
	266	{
916b7656	267	struct serial_state *info = tty->driver_data;
1da177e4 LT	268
	269	info->x_char = ch;
	270	if (ch) {
	271	/*
	272	* I guess we could call console->write() directly but
	273	* let's do that for now.
	274	*/
5e99d545	275	transmit_chars(tty, info, NULL);
1da177e4 LT	276	}
	277	}
	278
	279	/*
	280	* ------------------------------------------------------------
	281	* rs_throttle()
	282	*
	283	* This routine is called by the upper-layer tty layer to signal that
	284	* incoming characters should be throttled.
	285	* ------------------------------------------------------------
	286	*/
	287	static void rs_throttle(struct tty_struct * tty)
	288	{
f66279cd JS	289	if (I_IXOFF(tty))
f66279cd JS	290	rs_send_xchar(tty, STOP_CHAR(tty));
1da177e4 LT	291
	292	printk(KERN_INFO "simrs_throttle called\n");
	293	}
	294
	295	static void rs_unthrottle(struct tty_struct * tty)
	296	{
916b7656	297	struct serial_state *info = tty->driver_data;
1da177e4 LT	298
	299	if (I_IXOFF(tty)) {
	300	if (info->x_char)
	301	info->x_char = 0;
	302	else
	303	rs_send_xchar(tty, START_CHAR(tty));
	304	}
	305	printk(KERN_INFO "simrs_unthrottle called\n");
	306	}
	307
10e82f6c	308	static int rs_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg)
1da177e4 LT	309	{
	310	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	311	(cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
0587102c	312	(cmd != TIOCMIWAIT)) {
1da177e4 LT	313	if (tty->flags & (1 << TTY_IO_ERROR))
	314	return -EIO;
	315	}
	316
	317	switch (cmd) {
f66279cd JS	318	case TIOCGSERIAL:
	319	case TIOCSSERIAL:
	320	case TIOCSERGSTRUCT:
	321	case TIOCMIWAIT:
	322	return 0;
	323	case TIOCSERCONFIG:
	324	case TIOCSERGETLSR: /* Get line status register */
	325	return -EINVAL;
	326	case TIOCSERGWILD:
	327	case TIOCSERSWILD:
	328	/* "setserial -W" is called in Debian boot */
	329	printk (KERN_INFO "TIOCSER?WILD ioctl obsolete, ignored.\n");
	330	return 0;
	331	}
	332	return -ENOIOCTLCMD;
1da177e4 LT	333	}
	334
	335	#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK\|BRKINT\|IGNPAR\|PARMRK\|INPCK))
	336
f889a26a	337	static void rs_set_termios(struct tty_struct tty, struct ktermios old_termios)
1da177e4	338	{
1da177e4 LT	339	/* Handle turning off CRTSCTS */
1da177e4 LT	340	if ((old_termios->c_cflag & CRTSCTS) &&
adc8d746	341	!(tty->termios.c_cflag & CRTSCTS)) {
1da177e4	342	tty->hw_stopped = 0;
1da177e4 LT	343	}
	344	}
	345	/*
	346	* This routine will shutdown a serial port; interrupts are disabled, and
	347	* DTR is dropped if the hangup on close termio flag is on.
	348	*/
458cd31a	349	static void shutdown(struct tty_port *port)
1da177e4	350	{
458cd31a JS	351	struct serial_state *info = container_of(port, struct serial_state,
	352	port);
	353	unsigned long flags;
1da177e4 LT	354
1da177e4 LT	355	local_irq_save(flags);
f66279cd JS	356	if (info->irq)
f66279cd JS	357	free_irq(info->irq, info);
1da177e4	358
f66279cd JS	359	if (info->xmit.buf) {
	360	free_page((unsigned long) info->xmit.buf);
	361	info->xmit.buf = NULL;
1da177e4 LT	362	}
	363	local_irq_restore(flags);
	364	}
	365
1da177e4 LT	366	static void rs_close(struct tty_struct tty, struct file filp)
1da177e4 LT	367	{
916b7656	368	struct serial_state *info = tty->driver_data;
37343030	369
458cd31a	370	tty_port_close(&info->port, tty, filp);
1da177e4 LT	371	}
1da177e4 LT	372
1da177e4 LT	373	static void rs_hangup(struct tty_struct *tty)
1da177e4 LT	374	{
916b7656	375	struct serial_state *info = tty->driver_data;
1da177e4	376
1da177e4	377	rs_flush_buffer(tty);
458cd31a	378	tty_port_hangup(&info->port);
1da177e4 LT	379	}
1da177e4 LT	380
9aead90a	381	static int activate(struct tty_port port, struct tty_struct tty)
1da177e4	382	{
9aead90a JS	383	struct serial_state *state = container_of(port, struct serial_state,
9aead90a JS	384	port);
f66279cd JS	385	unsigned long flags, page;
f66279cd JS	386	int retval = 0;
1da177e4 LT	387
	388	page = get_zeroed_page(GFP_KERNEL);
	389	if (!page)
	390	return -ENOMEM;
	391
	392	local_irq_save(flags);
	393
916b7656	394	if (state->xmit.buf)
1da177e4 LT	395	free_page(page);
1da177e4 LT	396	else
916b7656	397	state->xmit.buf = (unsigned char *) page;
1da177e4	398
964105b5	399	if (state->irq) {
2f8c521a	400	retval = request_irq(state->irq, rs_interrupt_single, 0,
916b7656	401	"simserial", state);
9e12dd5f	402	if (retval)
1da177e4	403	goto errout;
1da177e4 LT	404	}
1da177e4 LT	405
916b7656	406	state->xmit.head = state->xmit.tail = 0;
1da177e4	407
1da177e4 LT	408	/*
	409	* Set up the tty->alt_speed kludge
	410	*/
01bd730d	411	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
5e99d545	412	tty->alt_speed = 57600;
01bd730d	413	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
5e99d545	414	tty->alt_speed = 115200;
01bd730d	415	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
5e99d545	416	tty->alt_speed = 230400;
01bd730d	417	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
5e99d545	418	tty->alt_speed = 460800;
1da177e4	419
1da177e4 LT	420	errout:
	421	local_irq_restore(flags);
	422	return retval;
	423	}
	424
	425
	426	/*
	427	* This routine is called whenever a serial port is opened. It
	428	* enables interrupts for a serial port, linking in its async structure into
	429	* the IRQ chain. It also performs the serial-specific
	430	* initialization for the tty structure.
	431	*/
	432	static int rs_open(struct tty_struct tty, struct file filp)
	433	{
916b7656	434	struct serial_state *info = rs_table + tty->index;
7f32f8dd	435	struct tty_port *port = &info->port;
1da177e4	436
916b7656	437	tty->driver_data = info;
7f32f8dd	438	tty->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
1da177e4	439
1da177e4 LT	440	/*
	441	* figure out which console to use (should be one already)
	442	*/
	443	console = console_drivers;
	444	while (console) {
	445	if ((console->flags & CON_ENABLED) && console->write) break;
	446	console = console->next;
	447	}
	448
9aead90a	449	return tty_port_open(port, tty, filp);
1da177e4 LT	450	}
	451
	452	/*
	453	* /proc fs routines....
	454	*/
	455
bf54215e	456	static int rs_proc_show(struct seq_file m, void v)
1da177e4	457	{
bf54215e AD	458	int i;
bf54215e AD	459
6e9ebcfa	460	seq_printf(m, "simserinfo:1.0\n");
bf54215e	461	for (i = 0; i < NR_PORTS; i++)
98e3a9e6 JS	462	seq_printf(m, "%d: uart:16550 port:3F8 irq:%d\n",
98e3a9e6 JS	463	i, rs_table[i].irq);
bf54215e	464	return 0;
1da177e4 LT	465	}
1da177e4 LT	466
bf54215e AD	467	static int rs_proc_open(struct inode inode, struct file file)
	468	{
	469	return single_open(file, rs_proc_show, NULL);
	470	}
	471
	472	static const struct file_operations rs_proc_fops = {
	473	.owner = THIS_MODULE,
	474	.open = rs_proc_open,
	475	.read = seq_read,
	476	.llseek = seq_lseek,
	477	.release = single_release,
	478	};
	479
b68e31d0	480	static const struct tty_operations hp_ops = {
1da177e4 LT	481	.open = rs_open,
	482	.close = rs_close,
	483	.write = rs_write,
	484	.put_char = rs_put_char,
	485	.flush_chars = rs_flush_chars,
	486	.write_room = rs_write_room,
	487	.chars_in_buffer = rs_chars_in_buffer,
	488	.flush_buffer = rs_flush_buffer,
	489	.ioctl = rs_ioctl,
	490	.throttle = rs_throttle,
	491	.unthrottle = rs_unthrottle,
	492	.send_xchar = rs_send_xchar,
	493	.set_termios = rs_set_termios,
1da177e4	494	.hangup = rs_hangup,
bf54215e	495	.proc_fops = &rs_proc_fops,
1da177e4 LT	496	};
1da177e4 LT	497
37343030	498	static const struct tty_port_operations hp_port_ops = {
9aead90a	499	.activate = activate,
458cd31a	500	.shutdown = shutdown,
37343030 JS	501	};
37343030 JS	502
fd2d7a6e	503	static int __init simrs_init(void)
1da177e4	504	{
fd2d7a6e JS	505	struct serial_state *state;
fd2d7a6e JS	506	int retval;
1da177e4 LT	507
	508	if (!ia64_platform_is("hpsim"))
	509	return -ENODEV;
	510
410235fd	511	hp_simserial_driver = alloc_tty_driver(NR_PORTS);
1da177e4 LT	512	if (!hp_simserial_driver)
	513	return -ENOMEM;
	514
6e9ebcfa	515	printk(KERN_INFO "SimSerial driver with no serial options enabled\n");
1da177e4 LT	516
	517	/* Initialize the tty_driver structure */
	518
1da177e4 LT	519	hp_simserial_driver->driver_name = "simserial";
	520	hp_simserial_driver->name = "ttyS";
	521	hp_simserial_driver->major = TTY_MAJOR;
	522	hp_simserial_driver->minor_start = 64;
	523	hp_simserial_driver->type = TTY_DRIVER_TYPE_SERIAL;
	524	hp_simserial_driver->subtype = SERIAL_TYPE_NORMAL;
	525	hp_simserial_driver->init_termios = tty_std_termios;
	526	hp_simserial_driver->init_termios.c_cflag =
	527	B9600 \| CS8 \| CREAD \| HUPCL \| CLOCAL;
	528	hp_simserial_driver->flags = TTY_DRIVER_REAL_RAW;
	529	tty_set_operations(hp_simserial_driver, &hp_ops);
	530
fd2d7a6e	531	state = rs_table;
7f32f8dd	532	tty_port_init(&state->port);
37343030	533	state->port.ops = &hp_port_ops;
7f32f8dd	534	state->port.close_delay = 0; /* XXX really 0? */
fd2d7a6e JS	535
	536	retval = hpsim_get_irq(KEYBOARD_INTR);
	537	if (retval < 0) {
	538	printk(KERN_ERR "%s: out of interrupt vectors!\n",
	539	__func__);
	540	goto err_free_tty;
	541	}
1da177e4	542
fd2d7a6e	543	state->irq = retval;
1da177e4	544
fd2d7a6e	545	/* the port is imaginary */
98e3a9e6	546	printk(KERN_INFO "ttyS0 at 0x03f8 (irq = %d) is a 16550\n", state->irq);
1da177e4	547
b19e2ca7	548	tty_port_link_device(&state->port, hp_simserial_driver, 0);
fd2d7a6e JS	549	retval = tty_register_driver(hp_simserial_driver);
	550	if (retval) {
	551	printk(KERN_ERR "Couldn't register simserial driver\n");
	552	goto err_free_tty;
1da177e4 LT	553	}
1da177e4 LT	554
1da177e4	555	return 0;
fd2d7a6e JS	556	err_free_tty:
fd2d7a6e JS	557	put_tty_driver(hp_simserial_driver);
191c5f10	558	tty_port_destroy(&state->port);
fd2d7a6e	559	return retval;
1da177e4 LT	560	}
	561
	562	#ifndef MODULE
	563	__initcall(simrs_init);
	564	#endif