[deliverable/linux.git] / drivers / input / serio / serport.c

/*
 * Input device TTY line discipline
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 *
 * This is a module that converts a tty line into a much simpler
 * 'serial io port' abstraction that the input device drivers use.
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <asm/uaccess.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/serio.h>
#include <linux/tty.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Input device TTY line discipline");
MODULE_LICENSE("GPL");
MODULE_ALIAS_LDISC(N_MOUSE);

#define SERPORT_BUSY	1
#define SERPORT_ACTIVE	2
#define SERPORT_DEAD	3

struct serport {
	struct tty_struct *tty;
	wait_queue_head_t wait;
	struct serio *serio;
	struct serio_device_id id;
	spinlock_t lock;
	unsigned long flags;
};

/*
 * Callback functions from the serio code.
 */

static int serport_serio_write(struct serio *serio, unsigned char data)
{
	struct serport *serport = serio->port_data;
	return -(serport->tty->driver->write(serport->tty, &data, 1) != 1);
}

static int serport_serio_open(struct serio *serio)
{
	struct serport *serport = serio->port_data;
	unsigned long flags;

	spin_lock_irqsave(&serport->lock, flags);
	set_bit(SERPORT_ACTIVE, &serport->flags);
	spin_unlock_irqrestore(&serport->lock, flags);

	return 0;
}


static void serport_serio_close(struct serio *serio)
{
	struct serport *serport = serio->port_data;
	unsigned long flags;

	spin_lock_irqsave(&serport->lock, flags);
	clear_bit(SERPORT_ACTIVE, &serport->flags);
	set_bit(SERPORT_DEAD, &serport->flags);
	spin_unlock_irqrestore(&serport->lock, flags);

	wake_up_interruptible(&serport->wait);
}

/*
 * serport_ldisc_open() is the routine that is called upon setting our line
 * discipline on a tty. It prepares the serio struct.
 */

static int serport_ldisc_open(struct tty_struct *tty)
{
	struct serport *serport;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	serport = kcalloc(1, sizeof(struct serport), GFP_KERNEL);
	if (!serport)
		return -ENOMEM;

	serport->tty = tty;
	spin_lock_init(&serport->lock);
	init_waitqueue_head(&serport->wait);

	tty->disc_data = serport;
	set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);

	return 0;
}

/*
 * serport_ldisc_close() is the opposite of serport_ldisc_open()
 */

static void serport_ldisc_close(struct tty_struct *tty)
{
	struct serport *serport = (struct serport *) tty->disc_data;

	kfree(serport);
}

/*
 * serport_ldisc_receive() is called by the low level tty driver when characters
 * are ready for us. We forward the characters, one by one to the 'interrupt'
 * routine.
 *
 * FIXME: We should get pt_regs from the tty layer and forward them to
 *	  serio_interrupt here.
 */

static void serport_ldisc_receive(struct tty_struct *tty, const unsigned char *cp, char *fp, int count)
{
	struct serport *serport = (struct serport*) tty->disc_data;
	unsigned long flags;
	int i;

	spin_lock_irqsave(&serport->lock, flags);

	if (!test_bit(SERPORT_ACTIVE, &serport->flags))
		goto out;

	for (i = 0; i < count; i++)
		serio_interrupt(serport->serio, cp[i], 0, NULL);

out:
	spin_unlock_irqrestore(&serport->lock, flags);
}

/*
 * serport_ldisc_room() reports how much room we do have for receiving data.
 * Although we in fact have infinite room, we need to specify some value
 * here, and 256 seems to be reasonable.
 */

static int serport_ldisc_room(struct tty_struct *tty)
{
	return 256;
}

/*
 * serport_ldisc_read() just waits indefinitely if everything goes well.
 * However, when the serio driver closes the serio port, it finishes,
 * returning 0 characters.
 */

static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, unsigned char __user * buf, size_t nr)
{
	struct serport *serport = (struct serport*) tty->disc_data;
	struct serio *serio;
	char name[64];

	if (test_and_set_bit(SERPORT_BUSY, &serport->flags))
		return -EBUSY;

	serport->serio = serio = kcalloc(1, sizeof(struct serio), GFP_KERNEL);
	if (!serio)
		return -ENOMEM;

	strlcpy(serio->name, "Serial port", sizeof(serio->name));
	snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", tty_name(tty, name));
	serio->id = serport->id;
	serio->id.type = SERIO_RS232;
	serio->write = serport_serio_write;
	serio->open = serport_serio_open;
	serio->close = serport_serio_close;
	serio->port_data = serport;

	serio_register_port(serport->serio);
	printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name));

	wait_event_interruptible(serport->wait, test_bit(SERPORT_DEAD, &serport->flags));
	serio_unregister_port(serport->serio);
	serport->serio = NULL;

	clear_bit(SERPORT_DEAD, &serport->flags);
	clear_bit(SERPORT_BUSY, &serport->flags);

	return 0;
}

/*
 * serport_ldisc_ioctl() allows to set the port protocol, and device ID
 */

static int serport_ldisc_ioctl(struct tty_struct * tty, struct file * file, unsigned int cmd, unsigned long arg)
{
	struct serport *serport = (struct serport*) tty->disc_data;
	unsigned long type;

	if (cmd == SPIOCSTYPE) {
		if (get_user(type, (unsigned long __user *) arg))
			return -EFAULT;

		serport->id.proto = type & 0x000000ff;
		serport->id.id	  = (type & 0x0000ff00) >> 8;
		serport->id.extra = (type & 0x00ff0000) >> 16;

		return 0;
	}

	return -EINVAL;
}

static void serport_ldisc_write_wakeup(struct tty_struct * tty)
{
	struct serport *serport = (struct serport *) tty->disc_data;
	unsigned long flags;

	spin_lock_irqsave(&serport->lock, flags);
	if (test_bit(SERPORT_ACTIVE, &serport->flags))
		serio_drv_write_wakeup(serport->serio);
	spin_unlock_irqrestore(&serport->lock, flags);
}

/*
 * The line discipline structure.
 */

static struct tty_ldisc serport_ldisc = {
	.owner =	THIS_MODULE,
	.name =		"input",
	.open =		serport_ldisc_open,
	.close =	serport_ldisc_close,
	.read =		serport_ldisc_read,
	.ioctl =	serport_ldisc_ioctl,
	.receive_buf =	serport_ldisc_receive,
	.receive_room =	serport_ldisc_room,
	.write_wakeup =	serport_ldisc_write_wakeup
};

/*
 * The functions for insering/removing us as a module.
 */

static int __init serport_init(void)
{
	int retval;
	retval = tty_register_ldisc(N_MOUSE, &serport_ldisc);
	if (retval)
		printk(KERN_ERR "serport.c: Error registering line discipline.\n");

	return  retval;
}

static void __exit serport_exit(void)
{
	tty_unregister_ldisc(N_MOUSE);
}

module_init(serport_init);
module_exit(serport_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Input device TTY line discipline
	3	*
	4	* Copyright (c) 1999-2002 Vojtech Pavlik
	5	*
	6	* This is a module that converts a tty line into a much simpler
	7	* 'serial io port' abstraction that the input device drivers use.
	8	*/
	9
	10	/*
	11	* This program is free software; you can redistribute it and/or modify it
	12	* under the terms of the GNU General Public License version 2 as published by
	13	* the Free Software Foundation.
	14	*/
	15
	16	#include <asm/uaccess.h>
	17	#include <linux/kernel.h>
	18	#include <linux/slab.h>
	19	#include <linux/module.h>
	20	#include <linux/init.h>
	21	#include <linux/serio.h>
	22	#include <linux/tty.h>
	23
	24	MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
	25	MODULE_DESCRIPTION("Input device TTY line discipline");
	26	MODULE_LICENSE("GPL");
	27	MODULE_ALIAS_LDISC(N_MOUSE);
	28
	29	#define SERPORT_BUSY 1
1ff2c873 DT	30	#define SERPORT_ACTIVE 2
1ff2c873 DT	31	#define SERPORT_DEAD 3
1da177e4 LT	32
	33	struct serport {
	34	struct tty_struct *tty;
	35	wait_queue_head_t wait;
	36	struct serio *serio;
1ff2c873 DT	37	struct serio_device_id id;
1ff2c873 DT	38	spinlock_t lock;
1da177e4 LT	39	unsigned long flags;
	40	};
	41
	42	/*
	43	* Callback functions from the serio code.
	44	*/
	45
	46	static int serport_serio_write(struct serio *serio, unsigned char data)
	47	{
	48	struct serport *serport = serio->port_data;
	49	return -(serport->tty->driver->write(serport->tty, &data, 1) != 1);
	50	}
	51
1ff2c873 DT	52	static int serport_serio_open(struct serio *serio)
	53	{
	54	struct serport *serport = serio->port_data;
	55	unsigned long flags;
	56
	57	spin_lock_irqsave(&serport->lock, flags);
	58	set_bit(SERPORT_ACTIVE, &serport->flags);
	59	spin_unlock_irqrestore(&serport->lock, flags);
	60
	61	return 0;
	62	}
	63
	64
1da177e4 LT	65	static void serport_serio_close(struct serio *serio)
	66	{
	67	struct serport *serport = serio->port_data;
1ff2c873 DT	68	unsigned long flags;
	69
	70	spin_lock_irqsave(&serport->lock, flags);
	71	clear_bit(SERPORT_ACTIVE, &serport->flags);
	72	set_bit(SERPORT_DEAD, &serport->flags);
	73	spin_unlock_irqrestore(&serport->lock, flags);
1da177e4	74
1da177e4 LT	75	wake_up_interruptible(&serport->wait);
	76	}
	77
	78	/*
	79	* serport_ldisc_open() is the routine that is called upon setting our line
	80	* discipline on a tty. It prepares the serio struct.
	81	*/
	82
	83	static int serport_ldisc_open(struct tty_struct *tty)
	84	{
	85	struct serport *serport;
1da177e4 LT	86
	87	if (!capable(CAP_SYS_ADMIN))
	88	return -EPERM;
	89
1ff2c873 DT	90	serport = kcalloc(1, sizeof(struct serport), GFP_KERNEL);
1ff2c873 DT	91	if (!serport)
1da177e4	92	return -ENOMEM;
1da177e4	93
1da177e4	94	serport->tty = tty;
1ff2c873	95	spin_lock_init(&serport->lock);
1da177e4 LT	96	init_waitqueue_head(&serport->wait);
1da177e4 LT	97
1ff2c873 DT	98	tty->disc_data = serport;
	99	set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	100
1da177e4 LT	101	return 0;
	102	}
	103
	104	/*
	105	* serport_ldisc_close() is the opposite of serport_ldisc_open()
	106	*/
	107
	108	static void serport_ldisc_close(struct tty_struct *tty)
	109	{
1ff2c873 DT	110	struct serport serport = (struct serport ) tty->disc_data;
1ff2c873 DT	111
1da177e4 LT	112	kfree(serport);
	113	}
	114
	115	/*
	116	* serport_ldisc_receive() is called by the low level tty driver when characters
	117	* are ready for us. We forward the characters, one by one to the 'interrupt'
	118	* routine.
	119	*
	120	* FIXME: We should get pt_regs from the tty layer and forward them to
	121	* serio_interrupt here.
	122	*/
	123
	124	static void serport_ldisc_receive(struct tty_struct tty, const unsigned char cp, char *fp, int count)
	125	{
	126	struct serport serport = (struct serport) tty->disc_data;
1ff2c873	127	unsigned long flags;
1da177e4	128	int i;
1ff2c873 DT	129
	130	spin_lock_irqsave(&serport->lock, flags);
	131
	132	if (!test_bit(SERPORT_ACTIVE, &serport->flags))
	133	goto out;
	134
1da177e4 LT	135	for (i = 0; i < count; i++)
1da177e4 LT	136	serio_interrupt(serport->serio, cp[i], 0, NULL);
1ff2c873 DT	137
	138	out:
	139	spin_unlock_irqrestore(&serport->lock, flags);
1da177e4 LT	140	}
	141
	142	/*
	143	* serport_ldisc_room() reports how much room we do have for receiving data.
	144	* Although we in fact have infinite room, we need to specify some value
	145	* here, and 256 seems to be reasonable.
	146	*/
	147
	148	static int serport_ldisc_room(struct tty_struct *tty)
	149	{
	150	return 256;
	151	}
	152
	153	/*
	154	* serport_ldisc_read() just waits indefinitely if everything goes well.
	155	* However, when the serio driver closes the serio port, it finishes,
	156	* returning 0 characters.
	157	*/
	158
	159	static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, unsigned char __user * buf, size_t nr)
	160	{
	161	struct serport serport = (struct serport) tty->disc_data;
1ff2c873	162	struct serio *serio;
1da177e4 LT	163	char name[64];
	164
	165	if (test_and_set_bit(SERPORT_BUSY, &serport->flags))
	166	return -EBUSY;
	167
1ff2c873 DT	168	serport->serio = serio = kcalloc(1, sizeof(struct serio), GFP_KERNEL);
	169	if (!serio)
	170	return -ENOMEM;
	171
	172	strlcpy(serio->name, "Serial port", sizeof(serio->name));
	173	snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", tty_name(tty, name));
	174	serio->id = serport->id;
	175	serio->id.type = SERIO_RS232;
	176	serio->write = serport_serio_write;
	177	serio->open = serport_serio_open;
	178	serio->close = serport_serio_close;
	179	serio->port_data = serport;
	180
1da177e4 LT	181	serio_register_port(serport->serio);
1da177e4 LT	182	printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name));
1ff2c873 DT	183
1ff2c873 DT	184	wait_event_interruptible(serport->wait, test_bit(SERPORT_DEAD, &serport->flags));
1da177e4	185	serio_unregister_port(serport->serio);
1ff2c873	186	serport->serio = NULL;
1da177e4	187
1ff2c873	188	clear_bit(SERPORT_DEAD, &serport->flags);
1da177e4 LT	189	clear_bit(SERPORT_BUSY, &serport->flags);
	190
	191	return 0;
	192	}
	193
	194	/*
	195	* serport_ldisc_ioctl() allows to set the port protocol, and device ID
	196	*/
	197
	198	static int serport_ldisc_ioctl(struct tty_struct * tty, struct file * file, unsigned int cmd, unsigned long arg)
	199	{
	200	struct serport serport = (struct serport) tty->disc_data;
1da177e4 LT	201	unsigned long type;
	202
	203	if (cmd == SPIOCSTYPE) {
	204	if (get_user(type, (unsigned long __user *) arg))
	205	return -EFAULT;
	206
1ff2c873 DT	207	serport->id.proto = type & 0x000000ff;
	208	serport->id.id = (type & 0x0000ff00) >> 8;
	209	serport->id.extra = (type & 0x00ff0000) >> 16;
1da177e4 LT	210
	211	return 0;
	212	}
	213
	214	return -EINVAL;
	215	}
	216
	217	static void serport_ldisc_write_wakeup(struct tty_struct * tty)
	218	{
1ff2c873 DT	219	struct serport serport = (struct serport ) tty->disc_data;
1ff2c873 DT	220	unsigned long flags;
1da177e4	221
1ff2c873 DT	222	spin_lock_irqsave(&serport->lock, flags);
	223	if (test_bit(SERPORT_ACTIVE, &serport->flags))
	224	serio_drv_write_wakeup(serport->serio);
	225	spin_unlock_irqrestore(&serport->lock, flags);
1da177e4 LT	226	}
	227
	228	/*
	229	* The line discipline structure.
	230	*/
	231
	232	static struct tty_ldisc serport_ldisc = {
	233	.owner = THIS_MODULE,
	234	.name = "input",
	235	.open = serport_ldisc_open,
	236	.close = serport_ldisc_close,
	237	.read = serport_ldisc_read,
	238	.ioctl = serport_ldisc_ioctl,
	239	.receive_buf = serport_ldisc_receive,
	240	.receive_room = serport_ldisc_room,
	241	.write_wakeup = serport_ldisc_write_wakeup
	242	};
	243
	244	/*
	245	* The functions for insering/removing us as a module.
	246	*/
	247
	248	static int __init serport_init(void)
	249	{
	250	int retval;
	251	retval = tty_register_ldisc(N_MOUSE, &serport_ldisc);
	252	if (retval)
	253	printk(KERN_ERR "serport.c: Error registering line discipline.\n");
	254
	255	return retval;
	256	}
	257
	258	static void __exit serport_exit(void)
	259	{
64ccd715	260	tty_unregister_ldisc(N_MOUSE);
1da177e4 LT	261	}
	262
	263	module_init(serport_init);
	264	module_exit(serport_exit);