V4L/DVB: staging/lirc: add lirc_parallel driver

/*

 * lirc_parallel.c

 *

 * lirc_parallel - device driver for infra-red signal receiving and

 *                 transmitting unit built by the author

 *

 * Copyright (C) 1998 Christoph Bartelmus <lirc@bartelmus.de>

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 */

/*** Includes ***/

#ifdef CONFIG_SMP

#error "--- Sorry, this driver is not SMP safe. ---"

#endif

#include <linux/module.h>

#include <linux/sched.h>

#include <linux/errno.h>

#include <linux/signal.h>

#include <linux/fs.h>

#include <linux/kernel.h>

#include <linux/ioport.h>

#include <linux/time.h>

#include <linux/mm.h>

#include <linux/delay.h>

#include <linux/io.h>

#include <linux/signal.h>

#include <linux/irq.h>

#include <linux/uaccess.h>

#include <asm/div64.h>

#include <linux/poll.h>

#include <linux/parport.h>

#include <media/lirc.h>

#include <media/lirc_dev.h>

#include "lirc_parallel.h"

#define LIRC_DRIVER_NAME "lirc_parallel"

#ifndef LIRC_IRQ

#define LIRC_IRQ 7

#endif

#ifndef LIRC_PORT

#define LIRC_PORT 0x378

#endif

#ifndef LIRC_TIMER

#define LIRC_TIMER 65536

#endif

/*** Global Variables ***/

static int debug;

static int check_pselecd;

unsigned int irq = LIRC_IRQ;

unsigned int io = LIRC_PORT;

#ifdef LIRC_TIMER

unsigned int timer;

unsigned int default_timer = LIRC_TIMER;

#endif

#define RBUF_SIZE (256) /* this must be a power of 2 larger than 1 */

static int rbuf[RBUF_SIZE];

DECLARE_WAIT_QUEUE_HEAD(lirc_wait);

unsigned int rptr;

unsigned int wptr;

unsigned int lost_irqs;

int is_open;

struct parport *pport;

struct pardevice *ppdevice;

int is_claimed;

unsigned int tx_mask = 1;

/*** Internal Functions ***/

static unsigned int in(int offset)

{

	switch (offset) {

	case LIRC_LP_BASE:

		return parport_read_data(pport);

	case LIRC_LP_STATUS:

		return parport_read_status(pport);

	case LIRC_LP_CONTROL:

		return parport_read_control(pport);

	}

	return 0; /* make compiler happy */

}

static void out(int offset, int value)

{

	switch (offset) {

	case LIRC_LP_BASE:

		parport_write_data(pport, value);

		break;

	case LIRC_LP_CONTROL:

		parport_write_control(pport, value);

		break;

	case LIRC_LP_STATUS:

		printk(KERN_INFO "%s: attempt to write to status register\n",

		       LIRC_DRIVER_NAME);

		break;

	}

}

static unsigned int lirc_get_timer(void)

{

	return in(LIRC_PORT_TIMER) & LIRC_PORT_TIMER_BIT;

}

static unsigned int lirc_get_signal(void)

{

	return in(LIRC_PORT_SIGNAL) & LIRC_PORT_SIGNAL_BIT;

}

static void lirc_on(void)

{

	out(LIRC_PORT_DATA, tx_mask);

}

static void lirc_off(void)

{

	out(LIRC_PORT_DATA, 0);

}

static unsigned int init_lirc_timer(void)

{

	struct timeval tv, now;

	unsigned int level, newlevel, timeelapsed, newtimer;

	int count = 0;

	do_gettimeofday(&tv);

	tv.tv_sec++;                     /* wait max. 1 sec. */

	level = lirc_get_timer();

	do {

		newlevel = lirc_get_timer();

		if (level == 0 && newlevel != 0)

			count++;

		level = newlevel;

		do_gettimeofday(&now);

	} while (count < 1000 && (now.tv_sec < tv.tv_sec

			     || (now.tv_sec == tv.tv_sec

				 && now.tv_usec < tv.tv_usec)));

	timeelapsed = ((now.tv_sec + 1 - tv.tv_sec)*1000000

		     + (now.tv_usec - tv.tv_usec));

	if (count >= 1000 && timeelapsed > 0) {

		if (default_timer == 0) {

			/* autodetect timer */

			newtimer = (1000000*count)/timeelapsed;

			printk(KERN_INFO "%s: %u Hz timer detected\n",

			       LIRC_DRIVER_NAME, newtimer);

			return newtimer;

		}  else {

			newtimer = (1000000*count)/timeelapsed;

			if (abs(newtimer - default_timer) > default_timer/10) {

				/* bad timer */

				printk(KERN_NOTICE "%s: bad timer: %u Hz\n",

				       LIRC_DRIVER_NAME, newtimer);

				printk(KERN_NOTICE "%s: using default timer: "

				       "%u Hz\n",

				       LIRC_DRIVER_NAME, default_timer);

				return default_timer;

			} else {

				printk(KERN_INFO "%s: %u Hz timer detected\n",

				       LIRC_DRIVER_NAME, newtimer);

				return newtimer; /* use detected value */

			}

		}

	} else {

		printk(KERN_NOTICE "%s: no timer detected\n", LIRC_DRIVER_NAME);

		return 0;

	}

}

static int lirc_claim(void)

{

	if (parport_claim(ppdevice) != 0) {

		printk(KERN_WARNING "%s: could not claim port\n",

		       LIRC_DRIVER_NAME);

		printk(KERN_WARNING "%s: waiting for port becoming available"

		       "\n", LIRC_DRIVER_NAME);

		if (parport_claim_or_block(ppdevice) < 0) {

			printk(KERN_NOTICE "%s: could not claim port, giving"

			       " up\n", LIRC_DRIVER_NAME);

			return 0;

		}

	}

	out(LIRC_LP_CONTROL, LP_PSELECP|LP_PINITP);

	is_claimed = 1;

	return 1;

}

/*** interrupt handler ***/

static void rbuf_write(int signal)

{

	unsigned int nwptr;

	nwptr = (wptr + 1) & (RBUF_SIZE - 1);

	if (nwptr == rptr) {

		/* no new signals will be accepted */

		lost_irqs++;

		printk(KERN_NOTICE "%s: buffer overrun\n", LIRC_DRIVER_NAME);

		return;

	}

	rbuf[wptr] = signal;

	wptr = nwptr;

}

static void irq_handler(void *blah)

{

	struct timeval tv;

	static struct timeval lasttv;

	static int init;

	long signal;

	int data;

	unsigned int level, newlevel;

	unsigned int timeout;

	if (!module_refcount(THIS_MODULE))

		return;

	if (!is_claimed)

		return;

#if 0

	/* disable interrupt */

	  disable_irq(irq);

	  out(LIRC_PORT_IRQ, in(LIRC_PORT_IRQ) & (~LP_PINTEN));

#endif

	if (check_pselecd && (in(1) & LP_PSELECD))

		return;

#ifdef LIRC_TIMER

	if (init) {

		do_gettimeofday(&tv);

		signal = tv.tv_sec - lasttv.tv_sec;

		if (signal > 15)

			/* really long time */

			data = PULSE_MASK;

		else

			data = (int) (signal*1000000 +

					 tv.tv_usec - lasttv.tv_usec +

					 LIRC_SFH506_DELAY);

		rbuf_write(data); /* space */

	} else {

		if (timer == 0) {

			/*

			 * wake up; we'll lose this signal, but it will be

			 * garbage if the device is turned on anyway

			 */

			timer = init_lirc_timer();

			/* enable_irq(irq); */

			return;

		}

		init = 1;

	}

	timeout = timer/10;	/* timeout after 1/10 sec. */

	signal = 1;

	level = lirc_get_timer();

	do {

		newlevel = lirc_get_timer();

		if (level == 0 && newlevel != 0)

			signal++;

		level = newlevel;

		/* giving up */

		if (signal > timeout

		    || (check_pselecd && (in(1) & LP_PSELECD))) {

			signal = 0;

			printk(KERN_NOTICE "%s: timeout\n", LIRC_DRIVER_NAME);

			break;

		}

	} while (lirc_get_signal());

	if (signal != 0) {

		/* ajust value to usecs */

		unsigned long long helper;

		helper = ((unsigned long long) signal)*1000000;

		do_div(helper, timer);

		signal = (long) helper;

		if (signal > LIRC_SFH506_DELAY)

			data = signal - LIRC_SFH506_DELAY;

		else

			data = 1;

		rbuf_write(PULSE_BIT|data); /* pulse */

	}

	do_gettimeofday(&lasttv);

#else

	/* add your code here */

#endif

	wake_up_interruptible(&lirc_wait);

	/* enable interrupt */

	/*

	  enable_irq(irq);

	  out(LIRC_PORT_IRQ, in(LIRC_PORT_IRQ)|LP_PINTEN);

	*/

}

/*** file operations ***/

static loff_t lirc_lseek(struct file *filep, loff_t offset, int orig)

{

	return -ESPIPE;

}

static ssize_t lirc_read(struct file *filep, char *buf, size_t n, loff_t *ppos)

{

	int result = 0;

	int count = 0;

	DECLARE_WAITQUEUE(wait, current);

	if (n % sizeof(int))

		return -EINVAL;

	add_wait_queue(&lirc_wait, &wait);

	set_current_state(TASK_INTERRUPTIBLE);

	while (count < n) {

		if (rptr != wptr) {

			if (copy_to_user(buf+count, (char *) &rbuf[rptr],

					 sizeof(int))) {

				result = -EFAULT;

				break;

			}

			rptr = (rptr + 1) & (RBUF_SIZE - 1);

			count += sizeof(int);

		} else {

			if (filep->f_flags & O_NONBLOCK) {

				result = -EAGAIN;

				break;

			}

			if (signal_pending(current)) {

				result = -ERESTARTSYS;

				break;

			}

			schedule();

			set_current_state(TASK_INTERRUPTIBLE);

		}

	}

	remove_wait_queue(&lirc_wait, &wait);

	set_current_state(TASK_RUNNING);

	return count ? count : result;

}

static ssize_t lirc_write(struct file *filep, const char *buf, size_t n,

			  loff_t *ppos)

{

	int count;

	unsigned int i;

	unsigned int level, newlevel;

	unsigned long flags;

	int counttimer;

	int *wbuf;

	if (!is_claimed)

		return -EBUSY;

	count = n / sizeof(int);

	if (n % sizeof(int) || count % 2 == 0)

		return -EINVAL;

	wbuf = memdup_user(buf, n);

	if (IS_ERR(wbuf))

		return PTR_ERR(wbuf);

#ifdef LIRC_TIMER

	if (timer == 0) {

		/* try again if device is ready */

		timer = init_lirc_timer();

		if (timer == 0)

			return -EIO;

	}

	/* adjust values from usecs */

	for (i = 0; i < count; i++) {

		unsigned long long helper;

		helper = ((unsigned long long) wbuf[i])*timer;

		do_div(helper, 1000000);

		wbuf[i] = (int) helper;

	}

	local_irq_save(flags);

	i = 0;

	while (i < count) {

		level = lirc_get_timer();

		counttimer = 0;

		lirc_on();

		do {

			newlevel = lirc_get_timer();

			if (level == 0 && newlevel != 0)

				counttimer++;

			level = newlevel;

			if (check_pselecd && (in(1) & LP_PSELECD)) {

				lirc_off();

				local_irq_restore(flags);

				return -EIO;

			}

		} while (counttimer < wbuf[i]);

		i++;

		lirc_off();

		if (i == count)

			break;

		counttimer = 0;

		do {

			newlevel = lirc_get_timer();

			if (level == 0 && newlevel != 0)

				counttimer++;

			level = newlevel;

			if (check_pselecd && (in(1) & LP_PSELECD)) {

				local_irq_restore(flags);

				return -EIO;

			}

		} while (counttimer < wbuf[i]);

		i++;

	}

	local_irq_restore(flags);

#else

	/* place code that handles write without external timer here */

#endif

	return n;

}

static unsigned int lirc_poll(struct file *file, poll_table *wait)

{

	poll_wait(file, &lirc_wait, wait);

	if (rptr != wptr)

		return POLLIN | POLLRDNORM;

	return 0;

}

static long lirc_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)

{

	int result;

	unsigned long features = LIRC_CAN_SET_TRANSMITTER_MASK |

				 LIRC_CAN_SEND_PULSE | LIRC_CAN_REC_MODE2;

	unsigned long mode;

	unsigned int ivalue;

	switch (cmd) {

	case LIRC_GET_FEATURES:

		result = put_user(features, (unsigned long *) arg);

		if (result)

			return result;

		break;

	case LIRC_GET_SEND_MODE:

		result = put_user(LIRC_MODE_PULSE, (unsigned long *) arg);

		if (result)

			return result;

		break;

	case LIRC_GET_REC_MODE:

		result = put_user(LIRC_MODE_MODE2, (unsigned long *) arg);

		if (result)

			return result;

		break;

	case LIRC_SET_SEND_MODE:

		result = get_user(mode, (unsigned long *) arg);

		if (result)

			return result;

		if (mode != LIRC_MODE_PULSE)

			return -EINVAL;

		break;

	case LIRC_SET_REC_MODE:

		result = get_user(mode, (unsigned long *) arg);

		if (result)

			return result;

		if (mode != LIRC_MODE_MODE2)

			return -ENOSYS;

		break;

	case LIRC_SET_TRANSMITTER_MASK:

		result = get_user(ivalue, (unsigned int *) arg);

		if (result)

			return result;

		if ((ivalue & LIRC_PARALLEL_TRANSMITTER_MASK) != ivalue)

			return LIRC_PARALLEL_MAX_TRANSMITTERS;

		tx_mask = ivalue;

		break;

	default:

		return -ENOIOCTLCMD;

	}

	return 0;

}

static int lirc_open(struct inode *node, struct file *filep)

{

	if (module_refcount(THIS_MODULE) || !lirc_claim())

		return -EBUSY;

	parport_enable_irq(pport);

	/* init read ptr */

	rptr = 0;

	wptr = 0;

	lost_irqs = 0;

	is_open = 1;

	return 0;

}

static int lirc_close(struct inode *node, struct file *filep)

{

	if (is_claimed) {

		is_claimed = 0;

		parport_release(ppdevice);

	}

	is_open = 0;

	return 0;

}

static struct file_operations lirc_fops = {

	.owner		= THIS_MODULE,

	.llseek		= lirc_lseek,

	.read		= lirc_read,

	.write		= lirc_write,

	.poll		= lirc_poll,

	.unlocked_ioctl	= lirc_ioctl,

	.open		= lirc_open,

	.release	= lirc_close

};

static int set_use_inc(void *data)

{

	return 0;

}

static void set_use_dec(void *data)

{

}

static struct lirc_driver driver = {

       .name		= LIRC_DRIVER_NAME,

       .minor		= -1,

       .code_length	= 1,

       .sample_rate	= 0,

       .data		= NULL,

       .add_to_buf	= NULL,

       .set_use_inc	= set_use_inc,

       .set_use_dec	= set_use_dec,

       .fops		= &lirc_fops,

       .dev		= NULL,

       .owner		= THIS_MODULE,

};

static int pf(void *handle);

static void kf(void *handle);

static struct timer_list poll_timer;

static void poll_state(unsigned long ignored);

static void poll_state(unsigned long ignored)

{

	printk(KERN_NOTICE "%s: time\n",

	       LIRC_DRIVER_NAME);

	del_timer(&poll_timer);

	if (is_claimed)

		return;

	kf(NULL);

	if (!is_claimed) {

		printk(KERN_NOTICE "%s: could not claim port, giving up\n",

		       LIRC_DRIVER_NAME);

		init_timer(&poll_timer);

		poll_timer.expires = jiffies + HZ;

		poll_timer.data = (unsigned long)current;

		poll_timer.function = poll_state;

		add_timer(&poll_timer);

	}

}

static int pf(void *handle)

{

	parport_disable_irq(pport);

	is_claimed = 0;

	return 0;

}

static void kf(void *handle)

{

	if (!is_open)

		return;

	if (!lirc_claim())

		return;

	parport_enable_irq(pport);

	lirc_off();

	/* this is a bit annoying when you actually print...*/

	/*

	printk(KERN_INFO "%s: reclaimed port\n", LIRC_DRIVER_NAME);

	*/

}

/*** module initialization and cleanup ***/

static int __init lirc_parallel_init(void)

{

	pport = parport_find_base(io);

	if (pport == NULL) {

		printk(KERN_NOTICE "%s: no port at %x found\n",

		       LIRC_DRIVER_NAME, io);

		return -ENXIO;

	}

	ppdevice = parport_register_device(pport, LIRC_DRIVER_NAME,

					   pf, kf, irq_handler, 0, NULL);

	parport_put_port(pport);

	if (ppdevice == NULL) {

		printk(KERN_NOTICE "%s: parport_register_device() failed\n",

		       LIRC_DRIVER_NAME);

		return -ENXIO;

	}

	if (parport_claim(ppdevice) != 0)

		goto skip_init;

	is_claimed = 1;

	out(LIRC_LP_CONTROL, LP_PSELECP|LP_PINITP);

#ifdef LIRC_TIMER

	if (debug)

		out(LIRC_PORT_DATA, tx_mask);

	timer = init_lirc_timer();

#if 0	/* continue even if device is offline */

	if (timer == 0) {

		is_claimed = 0;

		parport_release(pport);

		parport_unregister_device(ppdevice);

		return -EIO;

	}

#endif

	if (debug)

		out(LIRC_PORT_DATA, 0);

#endif

	is_claimed = 0;

	parport_release(ppdevice);

 skip_init:

	driver.minor = lirc_register_driver(&driver);

	if (driver.minor < 0) {

		printk(KERN_NOTICE "%s: register_chrdev() failed\n",

		       LIRC_DRIVER_NAME);

		parport_unregister_device(ppdevice);

		return -EIO;

	}

	printk(KERN_INFO "%s: installed using port 0x%04x irq %d\n",

	       LIRC_DRIVER_NAME, io, irq);

	return 0;