[net-next-2.6.git] / drivers / media / IR / lirc_dev.c

/*
 * LIRC base driver
 *
 * by Artur Lipowski <alipowski@interia.pl>
 *
 *  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
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/ioctl.h>
#include <linux/fs.h>
#include <linux/poll.h>
#include <linux/completion.h>
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/wait.h>
#include <linux/unistd.h>
#include <linux/kthread.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/cdev.h>

#include <media/lirc.h>
#include <media/lirc_dev.h>

static int debug;

#define IRCTL_DEV_NAME	"BaseRemoteCtl"
#define NOPLUG		-1
#define LOGHEAD		"lirc_dev (%s[%d]): "

static dev_t lirc_base_dev;

struct irctl {
	struct lirc_driver d;
	int attached;
	int open;

	struct mutex irctl_lock;
	struct lirc_buffer *buf;
	unsigned int chunk_size;

	struct task_struct *task;
	long jiffies_to_wait;

	struct cdev cdev;
};

static DEFINE_MUTEX(lirc_dev_lock);

static struct irctl *irctls[MAX_IRCTL_DEVICES];

/* Only used for sysfs but defined to void otherwise */
static struct class *lirc_class;

/*  helper function
 *  initializes the irctl structure
 */
static void init_irctl(struct irctl *ir)
{
	dev_dbg(ir->d.dev, LOGHEAD "initializing irctl\n",
		ir->d.name, ir->d.minor);
	mutex_init(&ir->irctl_lock);
	ir->d.minor = NOPLUG;
}

static void cleanup(struct irctl *ir)
{
	dev_dbg(ir->d.dev, LOGHEAD "cleaning up\n", ir->d.name, ir->d.minor);

	device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));

	if (ir->buf != ir->d.rbuf) {
		lirc_buffer_free(ir->buf);
		kfree(ir->buf);
	}
	ir->buf = NULL;
}

/*  helper function
 *  reads key codes from driver and puts them into buffer
 *  returns 0 on success
 */
static int add_to_buf(struct irctl *ir)
{
	if (ir->d.add_to_buf) {
		int res = -ENODATA;
		int got_data = 0;

		/*
		 * service the device as long as it is returning
		 * data and we have space
		 */
get_data:
		res = ir->d.add_to_buf(ir->d.data, ir->buf);
		if (res == 0) {
			got_data++;
			goto get_data;
		}

		if (res == -ENODEV)
			kthread_stop(ir->task);

		return got_data ? 0 : res;
	}

	return 0;
}

/* main function of the polling thread
 */
static int lirc_thread(void *irctl)
{
	struct irctl *ir = irctl;

	dev_dbg(ir->d.dev, LOGHEAD "poll thread started\n",
		ir->d.name, ir->d.minor);

	do {
		if (ir->open) {
			if (ir->jiffies_to_wait) {
				set_current_state(TASK_INTERRUPTIBLE);
				schedule_timeout(ir->jiffies_to_wait);
			}
			if (kthread_should_stop())
				break;
			if (!add_to_buf(ir))
				wake_up_interruptible(&ir->buf->wait_poll);
		} else {
			set_current_state(TASK_INTERRUPTIBLE);
			schedule();
		}
	} while (!kthread_should_stop());

	dev_dbg(ir->d.dev, LOGHEAD "poll thread ended\n",
		ir->d.name, ir->d.minor);

	return 0;
}


static struct file_operations fops = {
	.owner		= THIS_MODULE,
	.read		= lirc_dev_fop_read,
	.write		= lirc_dev_fop_write,
	.poll		= lirc_dev_fop_poll,
	.unlocked_ioctl	= lirc_dev_fop_ioctl,
	.open		= lirc_dev_fop_open,
	.release	= lirc_dev_fop_close,
	.llseek		= noop_llseek,
};

static int lirc_cdev_add(struct irctl *ir)
{
	int retval;
	struct lirc_driver *d = &ir->d;

	if (d->fops) {
		cdev_init(&ir->cdev, d->fops);
		ir->cdev.owner = d->owner;
	} else {
		cdev_init(&ir->cdev, &fops);
		ir->cdev.owner = THIS_MODULE;
	}
	kobject_set_name(&ir->cdev.kobj, "lirc%d", d->minor);

	retval = cdev_add(&ir->cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
	if (retval)
		kobject_put(&ir->cdev.kobj);

	return retval;
}

int lirc_register_driver(struct lirc_driver *d)
{
	struct irctl *ir;
	int minor;
	int bytes_in_key;
	unsigned int chunk_size;
	unsigned int buffer_size;
	int err;

	if (!d) {
		printk(KERN_ERR "lirc_dev: lirc_register_driver: "
		       "driver pointer must be not NULL!\n");
		err = -EBADRQC;
		goto out;
	}

	if (MAX_IRCTL_DEVICES <= d->minor) {
		dev_err(d->dev, "lirc_dev: lirc_register_driver: "
			"\"minor\" must be between 0 and %d (%d)!\n",
			MAX_IRCTL_DEVICES-1, d->minor);
		err = -EBADRQC;
		goto out;
	}

	if (1 > d->code_length || (BUFLEN * 8) < d->code_length) {
		dev_err(d->dev, "lirc_dev: lirc_register_driver: "
			"code length in bits for minor (%d) "
			"must be less than %d!\n",
			d->minor, BUFLEN * 8);
		err = -EBADRQC;
		goto out;
	}

	dev_dbg(d->dev, "lirc_dev: lirc_register_driver: sample_rate: %d\n",
		d->sample_rate);
	if (d->sample_rate) {
		if (2 > d->sample_rate || HZ < d->sample_rate) {
			dev_err(d->dev, "lirc_dev: lirc_register_driver: "
				"sample_rate must be between 2 and %d!\n", HZ);
			err = -EBADRQC;
			goto out;
		}
		if (!d->add_to_buf) {
			dev_err(d->dev, "lirc_dev: lirc_register_driver: "
				"add_to_buf cannot be NULL when "
				"sample_rate is set\n");
			err = -EBADRQC;
			goto out;
		}
	} else if (!(d->fops && d->fops->read) && !d->rbuf) {
		dev_err(d->dev, "lirc_dev: lirc_register_driver: "
			"fops->read and rbuf cannot all be NULL!\n");
		err = -EBADRQC;
		goto out;
	} else if (!d->rbuf) {
		if (!(d->fops && d->fops->read && d->fops->poll &&
		      d->fops->unlocked_ioctl)) {
			dev_err(d->dev, "lirc_dev: lirc_register_driver: "
				"neither read, poll nor unlocked_ioctl can be NULL!\n");
			err = -EBADRQC;
			goto out;
		}
	}

	mutex_lock(&lirc_dev_lock);

	minor = d->minor;

	if (minor < 0) {
		/* find first free slot for driver */
		for (minor = 0; minor < MAX_IRCTL_DEVICES; minor++)
			if (!irctls[minor])
				break;
		if (MAX_IRCTL_DEVICES == minor) {
			dev_err(d->dev, "lirc_dev: lirc_register_driver: "
				"no free slots for drivers!\n");
			err = -ENOMEM;
			goto out_lock;
		}
	} else if (irctls[minor]) {
		dev_err(d->dev, "lirc_dev: lirc_register_driver: "
			"minor (%d) just registered!\n", minor);
		err = -EBUSY;
		goto out_lock;
	}

	ir = kzalloc(sizeof(struct irctl), GFP_KERNEL);
	if (!ir) {
		err = -ENOMEM;
		goto out_lock;
	}
	init_irctl(ir);
	irctls[minor] = ir;
	d->minor = minor;

	if (d->sample_rate) {
		ir->jiffies_to_wait = HZ / d->sample_rate;
	} else {
		/* it means - wait for external event in task queue */
		ir->jiffies_to_wait = 0;
	}

	/* some safety check 8-) */
	d->name[sizeof(d->name)-1] = '\0';

	bytes_in_key = BITS_TO_LONGS(d->code_length) +
			(d->code_length % 8 ? 1 : 0);
	buffer_size = d->buffer_size ? d->buffer_size : BUFLEN / bytes_in_key;
	chunk_size  = d->chunk_size  ? d->chunk_size  : bytes_in_key;

	if (d->rbuf) {
		ir->buf = d->rbuf;
	} else {
		ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
		if (!ir->buf) {
			err = -ENOMEM;
			goto out_lock;
		}
		err = lirc_buffer_init(ir->buf, chunk_size, buffer_size);
		if (err) {
			kfree(ir->buf);
			goto out_lock;
		}
	}
	ir->chunk_size = ir->buf->chunk_size;

	if (d->features == 0)
		d->features = LIRC_CAN_REC_LIRCCODE;

	ir->d = *d;
	ir->d.minor = minor;

	device_create(lirc_class, ir->d.dev,
		      MKDEV(MAJOR(lirc_base_dev), ir->d.minor), NULL,
		      "lirc%u", ir->d.minor);

	if (d->sample_rate) {
		/* try to fire up polling thread */
		ir->task = kthread_run(lirc_thread, (void *)ir, "lirc_dev");
		if (IS_ERR(ir->task)) {
			dev_err(d->dev, "lirc_dev: lirc_register_driver: "
				"cannot run poll thread for minor = %d\n",
				d->minor);
			err = -ECHILD;
			goto out_sysfs;
		}
	}

	err = lirc_cdev_add(ir);
	if (err)
		goto out_sysfs;

	ir->attached = 1;
	mutex_unlock(&lirc_dev_lock);

	dev_info(ir->d.dev, "lirc_dev: driver %s registered at minor = %d\n",
		 ir->d.name, ir->d.minor);
	return minor;

out_sysfs:
	device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
out_lock:
	mutex_unlock(&lirc_dev_lock);
out:
	return err;
}
EXPORT_SYMBOL(lirc_register_driver);

int lirc_unregister_driver(int minor)
{
	struct irctl *ir;

	if (minor < 0 || minor >= MAX_IRCTL_DEVICES) {
		printk(KERN_ERR "lirc_dev: lirc_unregister_driver: "
		       "\"minor (%d)\" must be between 0 and %d!\n",
		       minor, MAX_IRCTL_DEVICES-1);
		return -EBADRQC;
	}

	ir = irctls[minor];

	mutex_lock(&lirc_dev_lock);

	if (ir->d.minor != minor) {
		printk(KERN_ERR "lirc_dev: lirc_unregister_driver: "
		       "minor (%d) device not registered!", minor);
		mutex_unlock(&lirc_dev_lock);
		return -ENOENT;
	}

	/* end up polling thread */
	if (ir->task)
		kthread_stop(ir->task);

	dev_dbg(ir->d.dev, "lirc_dev: driver %s unregistered from minor = %d\n",
		ir->d.name, ir->d.minor);

	ir->attached = 0;
	if (ir->open) {
		dev_dbg(ir->d.dev, LOGHEAD "releasing opened driver\n",
			ir->d.name, ir->d.minor);
		wake_up_interruptible(&ir->buf->wait_poll);
		mutex_lock(&ir->irctl_lock);
		ir->d.set_use_dec(ir->d.data);
		module_put(ir->d.owner);
		mutex_unlock(&ir->irctl_lock);
		cdev_del(&ir->cdev);
	} else {
		cleanup(ir);
		cdev_del(&ir->cdev);
		kfree(ir);
		irctls[minor] = NULL;
	}

	mutex_unlock(&lirc_dev_lock);

	return 0;
}
EXPORT_SYMBOL(lirc_unregister_driver);

int lirc_dev_fop_open(struct inode *inode, struct file *file)
{
	struct irctl *ir;
	int retval = 0;

	if (iminor(inode) >= MAX_IRCTL_DEVICES) {
		printk(KERN_WARNING "lirc_dev [%d]: open result = -ENODEV\n",
		       iminor(inode));
		return -ENODEV;
	}

	if (mutex_lock_interruptible(&lirc_dev_lock))
		return -ERESTARTSYS;

	ir = irctls[iminor(inode)];
	if (!ir) {
		retval = -ENODEV;
		goto error;
	}
	file->private_data = ir;

	dev_dbg(ir->d.dev, LOGHEAD "open called\n", ir->d.name, ir->d.minor);

	if (ir->d.minor == NOPLUG) {
		retval = -ENODEV;
		goto error;
	}

	if (ir->open) {
		retval = -EBUSY;
		goto error;
	}

	if (try_module_get(ir->d.owner)) {
		++ir->open;
		retval = ir->d.set_use_inc(ir->d.data);

		if (retval) {
			module_put(ir->d.owner);
			--ir->open;
		} else {
			lirc_buffer_clear(ir->buf);
		}
		if (ir->task)
			wake_up_process(ir->task);
	}

error:
	if (ir)
		dev_dbg(ir->d.dev, LOGHEAD "open result = %d\n",
			ir->d.name, ir->d.minor, retval);

	mutex_unlock(&lirc_dev_lock);

	nonseekable_open(inode, file);

	return retval;
}
EXPORT_SYMBOL(lirc_dev_fop_open);

int lirc_dev_fop_close(struct inode *inode, struct file *file)
{
	struct irctl *ir = irctls[iminor(inode)];

	dev_dbg(ir->d.dev, LOGHEAD "close called\n", ir->d.name, ir->d.minor);

	WARN_ON(mutex_lock_killable(&lirc_dev_lock));

	--ir->open;
	if (ir->attached) {
		ir->d.set_use_dec(ir->d.data);
		module_put(ir->d.owner);
	} else {
		cleanup(ir);
		irctls[ir->d.minor] = NULL;
		kfree(ir);
	}

	mutex_unlock(&lirc_dev_lock);

	return 0;
}
EXPORT_SYMBOL(lirc_dev_fop_close);

unsigned int lirc_dev_fop_poll(struct file *file, poll_table *wait)
{
	struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
	unsigned int ret;

	dev_dbg(ir->d.dev, LOGHEAD "poll called\n", ir->d.name, ir->d.minor);

	if (!ir->attached) {
		mutex_unlock(&ir->irctl_lock);
		return POLLERR;
	}

	poll_wait(file, &ir->buf->wait_poll, wait);

	if (ir->buf)
		if (lirc_buffer_empty(ir->buf))
			ret = 0;
		else
			ret = POLLIN | POLLRDNORM;
	else
		ret = POLLERR;

	dev_dbg(ir->d.dev, LOGHEAD "poll result = %d\n",
		ir->d.name, ir->d.minor, ret);

	return ret;
}
EXPORT_SYMBOL(lirc_dev_fop_poll);

long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	unsigned long mode;
	int result = 0;
	struct irctl *ir = file->private_data;

	dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n",
		ir->d.name, ir->d.minor, cmd);

	if (ir->d.minor == NOPLUG || !ir->attached) {
		dev_dbg(ir->d.dev, LOGHEAD "ioctl result = -ENODEV\n",
			ir->d.name, ir->d.minor);
		return -ENODEV;
	}

	mutex_lock(&ir->irctl_lock);

	switch (cmd) {
	case LIRC_GET_FEATURES:
		result = put_user(ir->d.features, (unsigned long *)arg);
		break;
	case LIRC_GET_REC_MODE:
		if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
			result = -ENOSYS;
			break;
		}

		result = put_user(LIRC_REC2MODE
				  (ir->d.features & LIRC_CAN_REC_MASK),
				  (unsigned long *)arg);
		break;
	case LIRC_SET_REC_MODE:
		if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
			result = -ENOSYS;
			break;
		}

		result = get_user(mode, (unsigned long *)arg);
		if (!result && !(LIRC_MODE2REC(mode) & ir->d.features))
			result = -EINVAL;
		/*
		 * FIXME: We should actually set the mode somehow but
		 * for now, lirc_serial doesn't support mode changing either
		 */
		break;
	case LIRC_GET_LENGTH:
		result = put_user(ir->d.code_length, (unsigned long *)arg);
		break;
	case LIRC_GET_MIN_TIMEOUT:
		if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
		    ir->d.min_timeout == 0) {
			result = -ENOSYS;
			break;
		}

		result = put_user(ir->d.min_timeout, (unsigned long *)arg);
		break;
	case LIRC_GET_MAX_TIMEOUT:
		if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
		    ir->d.max_timeout == 0) {
			result = -ENOSYS;
			break;
		}

		result = put_user(ir->d.max_timeout, (unsigned long *)arg);
		break;
	default:
		result = -EINVAL;
	}

	dev_dbg(ir->d.dev, LOGHEAD "ioctl result = %d\n",
		ir->d.name, ir->d.minor, result);

	mutex_unlock(&ir->irctl_lock);

	return result;
}
EXPORT_SYMBOL(lirc_dev_fop_ioctl);

ssize_t lirc_dev_fop_read(struct file *file,
			  char *buffer,
			  size_t length,
			  loff_t *ppos)
{
	struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
	unsigned char buf[ir->chunk_size];
	int ret = 0, written = 0;
	DECLARE_WAITQUEUE(wait, current);

	dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor);

	if (mutex_lock_interruptible(&ir->irctl_lock))
		return -ERESTARTSYS;
	if (!ir->attached) {
		mutex_unlock(&ir->irctl_lock);
		return -ENODEV;
	}

	if (length % ir->chunk_size) {
		dev_dbg(ir->d.dev, LOGHEAD "read result = -EINVAL\n",
			ir->d.name, ir->d.minor);
		mutex_unlock(&ir->irctl_lock);
		return -EINVAL;
	}

	/*
	 * we add ourselves to the task queue before buffer check
	 * to avoid losing scan code (in case when queue is awaken somewhere
	 * between while condition checking and scheduling)
	 */
	add_wait_queue(&ir->buf->wait_poll, &wait);
	set_current_state(TASK_INTERRUPTIBLE);

	/*
	 * while we didn't provide 'length' bytes, device is opened in blocking
	 * mode and 'copy_to_user' is happy, wait for data.
	 */
	while (written < length && ret == 0) {
		if (lirc_buffer_empty(ir->buf)) {
			/* According to the read(2) man page, 'written' can be
			 * returned as less than 'length', instead of blocking
			 * again, returning -EWOULDBLOCK, or returning
			 * -ERESTARTSYS */
			if (written)
				break;
			if (file->f_flags & O_NONBLOCK) {
				ret = -EWOULDBLOCK;
				break;
			}
			if (signal_pending(current)) {
				ret = -ERESTARTSYS;
				break;
			}

			mutex_unlock(&ir->irctl_lock);
			schedule();
			set_current_state(TASK_INTERRUPTIBLE);

			if (mutex_lock_interruptible(&ir->irctl_lock)) {
				ret = -ERESTARTSYS;
				remove_wait_queue(&ir->buf->wait_poll, &wait);
				set_current_state(TASK_RUNNING);
				goto out_unlocked;
			}

			if (!ir->attached) {
				ret = -ENODEV;
				break;
			}
		} else {
			lirc_buffer_read(ir->buf, buf);
			ret = copy_to_user((void *)buffer+written, buf,
					   ir->buf->chunk_size);
			written += ir->buf->chunk_size;
		}
	}

	remove_wait_queue(&ir->buf->wait_poll, &wait);
	set_current_state(TASK_RUNNING);
	mutex_unlock(&ir->irctl_lock);

out_unlocked:
	dev_dbg(ir->d.dev, LOGHEAD "read result = %s (%d)\n",
		ir->d.name, ir->d.minor, ret ? "-EFAULT" : "OK", ret);

	return ret ? ret : written;
}
EXPORT_SYMBOL(lirc_dev_fop_read);

void *lirc_get_pdata(struct file *file)
{
	void *data = NULL;

	if (file && file->f_dentry && file->f_dentry->d_inode &&
	    file->f_dentry->d_inode->i_rdev) {
		struct irctl *ir;
		ir = irctls[iminor(file->f_dentry->d_inode)];
		data = ir->d.data;
	}

	return data;
}
EXPORT_SYMBOL(lirc_get_pdata);


ssize_t lirc_dev_fop_write(struct file *file, const char *buffer,
			   size_t length, loff_t *ppos)
{
	struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];

	dev_dbg(ir->d.dev, LOGHEAD "write called\n", ir->d.name, ir->d.minor);

	if (!ir->attached)
		return -ENODEV;

	return -EINVAL;
}
EXPORT_SYMBOL(lirc_dev_fop_write);


static int __init lirc_dev_init(void)
{
	int retval;

	lirc_class = class_create(THIS_MODULE, "lirc");
	if (IS_ERR(lirc_class)) {
		retval = PTR_ERR(lirc_class);
		printk(KERN_ERR "lirc_dev: class_create failed\n");
		goto error;
	}

	retval = alloc_chrdev_region(&lirc_base_dev, 0, MAX_IRCTL_DEVICES,
				     IRCTL_DEV_NAME);
	if (retval) {
		class_destroy(lirc_class);
		printk(KERN_ERR "lirc_dev: alloc_chrdev_region failed\n");
		goto error;
	}


	printk(KERN_INFO "lirc_dev: IR Remote Control driver registered, "
	       "major %d \n", MAJOR(lirc_base_dev));

error:
	return retval;
}


static void __exit lirc_dev_exit(void)
{
	class_destroy(lirc_class);
	unregister_chrdev_region(lirc_base_dev, MAX_IRCTL_DEVICES);
	printk(KERN_INFO "lirc_dev: module unloaded\n");
}

module_init(lirc_dev_init);
module_exit(lirc_dev_exit);

MODULE_DESCRIPTION("LIRC base driver module");
MODULE_AUTHOR("Artur Lipowski");
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Enable debugging messages");
Commit	Line	Data
4a62a5ab JW	1	/*
	2	* LIRC base driver
	3	*
	4	* by Artur Lipowski <alipowski@interia.pl>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*
	20	*/
	21
	22	#include <linux/module.h>
	23	#include <linux/kernel.h>
	24	#include <linux/sched.h>
	25	#include <linux/errno.h>
	26	#include <linux/ioctl.h>
	27	#include <linux/fs.h>
	28	#include <linux/poll.h>
	29	#include <linux/completion.h>
	30	#include <linux/errno.h>
	31	#include <linux/mutex.h>
	32	#include <linux/wait.h>
	33	#include <linux/unistd.h>
	34	#include <linux/kthread.h>
	35	#include <linux/bitops.h>
	36	#include <linux/device.h>
	37	#include <linux/cdev.h>
	38
	39	#include <media/lirc.h>
5690085e	40	#include <media/lirc_dev.h>
4a62a5ab JW	41
	42	static int debug;
	43
	44	#define IRCTL_DEV_NAME "BaseRemoteCtl"
	45	#define NOPLUG -1
	46	#define LOGHEAD "lirc_dev (%s[%d]): "
	47
	48	static dev_t lirc_base_dev;
	49
	50	struct irctl {
	51	struct lirc_driver d;
	52	int attached;
	53	int open;
	54
	55	struct mutex irctl_lock;
	56	struct lirc_buffer *buf;
	57	unsigned int chunk_size;
	58
	59	struct task_struct *task;
	60	long jiffies_to_wait;
	61
	62	struct cdev cdev;
	63	};
	64
	65	static DEFINE_MUTEX(lirc_dev_lock);
	66
	67	static struct irctl *irctls[MAX_IRCTL_DEVICES];
	68
	69	/* Only used for sysfs but defined to void otherwise */
	70	static struct class *lirc_class;
	71
	72	/* helper function
	73	* initializes the irctl structure
	74	*/
	75	static void init_irctl(struct irctl *ir)
	76	{
	77	dev_dbg(ir->d.dev, LOGHEAD "initializing irctl\n",
	78	ir->d.name, ir->d.minor);
	79	mutex_init(&ir->irctl_lock);
	80	ir->d.minor = NOPLUG;
	81	}
	82
	83	static void cleanup(struct irctl *ir)
	84	{
	85	dev_dbg(ir->d.dev, LOGHEAD "cleaning up\n", ir->d.name, ir->d.minor);
	86
	87	device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
	88
	89	if (ir->buf != ir->d.rbuf) {
	90	lirc_buffer_free(ir->buf);
	91	kfree(ir->buf);
	92	}
	93	ir->buf = NULL;
	94	}
	95
	96	/* helper function
	97	* reads key codes from driver and puts them into buffer
	98	* returns 0 on success
	99	*/
	100	static int add_to_buf(struct irctl *ir)
	101	{
	102	if (ir->d.add_to_buf) {
	103	int res = -ENODATA;
	104	int got_data = 0;
105
106	/*
107	* service the device as long as it is returning
108	* data and we have space
109	*/
110	get_data:
111	res = ir->d.add_to_buf(ir->d.data, ir->buf);
112	if (res == 0) {
113	got_data++;
114	goto get_data;
115	}
116
117	if (res == -ENODEV)
118	kthread_stop(ir->task);
119
120	return got_data ? 0 : res;
121	}
122
123	return 0;
124	}
125
126	/* main function of the polling thread
127	*/
128	static int lirc_thread(void *irctl)
129	{
130	struct irctl *ir = irctl;
131
132	dev_dbg(ir->d.dev, LOGHEAD "poll thread started\n",
133	ir->d.name, ir->d.minor);
134
135	do {
136	if (ir->open) {
137	if (ir->jiffies_to_wait) {
138	set_current_state(TASK_INTERRUPTIBLE);
139	schedule_timeout(ir->jiffies_to_wait);
140	}
141	if (kthread_should_stop())
142	break;
143	if (!add_to_buf(ir))
144	wake_up_interruptible(&ir->buf->wait_poll);
145	} else {
146	set_current_state(TASK_INTERRUPTIBLE);
147	schedule();
148	}
149	} while (!kthread_should_stop());
150
151	dev_dbg(ir->d.dev, LOGHEAD "poll thread ended\n",
152	ir->d.name, ir->d.minor);
153
154	return 0;
155	}
156
157
158	static struct file_operations fops = {
159	.owner = THIS_MODULE,
160	.read = lirc_dev_fop_read,
161	.write = lirc_dev_fop_write,
162	.poll = lirc_dev_fop_poll,
044e5878	163	.unlocked_ioctl = lirc_dev_fop_ioctl,
4a62a5ab JW	164	.open = lirc_dev_fop_open,
4a62a5ab JW	165	.release = lirc_dev_fop_close,
6038f373	166	.llseek = noop_llseek,
4a62a5ab JW	167	};
	168
	169	static int lirc_cdev_add(struct irctl *ir)
	170	{
	171	int retval;
	172	struct lirc_driver *d = &ir->d;
	173
	174	if (d->fops) {
	175	cdev_init(&ir->cdev, d->fops);
	176	ir->cdev.owner = d->owner;
	177	} else {
	178	cdev_init(&ir->cdev, &fops);
	179	ir->cdev.owner = THIS_MODULE;
	180	}
	181	kobject_set_name(&ir->cdev.kobj, "lirc%d", d->minor);
	182
	183	retval = cdev_add(&ir->cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
	184	if (retval)
	185	kobject_put(&ir->cdev.kobj);
	186
	187	return retval;
	188	}
	189
	190	int lirc_register_driver(struct lirc_driver *d)
	191	{
	192	struct irctl *ir;
	193	int minor;
	194	int bytes_in_key;
	195	unsigned int chunk_size;
	196	unsigned int buffer_size;
	197	int err;
	198
	199	if (!d) {
	200	printk(KERN_ERR "lirc_dev: lirc_register_driver: "
	201	"driver pointer must be not NULL!\n");
	202	err = -EBADRQC;
	203	goto out;
	204	}
	205
	206	if (MAX_IRCTL_DEVICES <= d->minor) {
	207	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
	208	"\"minor\" must be between 0 and %d (%d)!\n",
	209	MAX_IRCTL_DEVICES-1, d->minor);
	210	err = -EBADRQC;
	211	goto out;
	212	}
	213
	214	if (1 > d->code_length \|\| (BUFLEN * 8) < d->code_length) {
	215	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
	216	"code length in bits for minor (%d) "
	217	"must be less than %d!\n",
	218	d->minor, BUFLEN * 8);
	219	err = -EBADRQC;
	220	goto out;
	221	}
	222
	223	dev_dbg(d->dev, "lirc_dev: lirc_register_driver: sample_rate: %d\n",
	224	d->sample_rate);
	225	if (d->sample_rate) {
	226	if (2 > d->sample_rate \|\| HZ < d->sample_rate) {
	227	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
	228	"sample_rate must be between 2 and %d!\n", HZ);
	229	err = -EBADRQC;
	230	goto out;
231	}
232	if (!d->add_to_buf) {
233	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
234	"add_to_buf cannot be NULL when "
235	"sample_rate is set\n");
236	err = -EBADRQC;
237	goto out;
238	}
239	} else if (!(d->fops && d->fops->read) && !d->rbuf) {
240	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
241	"fops->read and rbuf cannot all be NULL!\n");
242	err = -EBADRQC;
243	goto out;
244	} else if (!d->rbuf) {
245	if (!(d->fops && d->fops->read && d->fops->poll &&
044e5878	246	d->fops->unlocked_ioctl)) {
4a62a5ab	247	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
044e5878	248	"neither read, poll nor unlocked_ioctl can be NULL!\n");
4a62a5ab JW	249	err = -EBADRQC;
	250	goto out;
	251	}
	252	}
	253
	254	mutex_lock(&lirc_dev_lock);
	255
	256	minor = d->minor;
	257
	258	if (minor < 0) {
	259	/* find first free slot for driver */
	260	for (minor = 0; minor < MAX_IRCTL_DEVICES; minor++)
	261	if (!irctls[minor])
	262	break;
	263	if (MAX_IRCTL_DEVICES == minor) {
	264	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
	265	"no free slots for drivers!\n");
	266	err = -ENOMEM;
	267	goto out_lock;
	268	}
	269	} else if (irctls[minor]) {
	270	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
	271	"minor (%d) just registered!\n", minor);
	272	err = -EBUSY;
	273	goto out_lock;
	274	}
	275
	276	ir = kzalloc(sizeof(struct irctl), GFP_KERNEL);
	277	if (!ir) {
	278	err = -ENOMEM;
	279	goto out_lock;
	280	}
	281	init_irctl(ir);
	282	irctls[minor] = ir;
	283	d->minor = minor;
	284
	285	if (d->sample_rate) {
	286	ir->jiffies_to_wait = HZ / d->sample_rate;
	287	} else {
	288	/* it means - wait for external event in task queue */
	289	ir->jiffies_to_wait = 0;
	290	}
	291
	292	/* some safety check 8-) */
	293	d->name[sizeof(d->name)-1] = '\0';
	294
	295	bytes_in_key = BITS_TO_LONGS(d->code_length) +
	296	(d->code_length % 8 ? 1 : 0);
	297	buffer_size = d->buffer_size ? d->buffer_size : BUFLEN / bytes_in_key;
	298	chunk_size = d->chunk_size ? d->chunk_size : bytes_in_key;
	299
	300	if (d->rbuf) {
	301	ir->buf = d->rbuf;
	302	} else {
	303	ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
	304	if (!ir->buf) {
	305	err = -ENOMEM;
	306	goto out_lock;
	307	}
	308	err = lirc_buffer_init(ir->buf, chunk_size, buffer_size);
	309	if (err) {
	310	kfree(ir->buf);
	311	goto out_lock;
	312	}
313	}
314	ir->chunk_size = ir->buf->chunk_size;
315
316	if (d->features == 0)
317	d->features = LIRC_CAN_REC_LIRCCODE;
318
319	ir->d = *d;
320	ir->d.minor = minor;
321
322	device_create(lirc_class, ir->d.dev,
323	MKDEV(MAJOR(lirc_base_dev), ir->d.minor), NULL,
324	"lirc%u", ir->d.minor);
325
326	if (d->sample_rate) {
327	/* try to fire up polling thread */
328	ir->task = kthread_run(lirc_thread, (void *)ir, "lirc_dev");
329	if (IS_ERR(ir->task)) {
330	dev_err(d->dev, "lirc_dev: lirc_register_driver: "
331	"cannot run poll thread for minor = %d\n",
332	d->minor);
333	err = -ECHILD;
334	goto out_sysfs;
335	}
336	}
337
338	err = lirc_cdev_add(ir);
339	if (err)
340	goto out_sysfs;
341
342	ir->attached = 1;
343	mutex_unlock(&lirc_dev_lock);
344
345	dev_info(ir->d.dev, "lirc_dev: driver %s registered at minor = %d\n",
346	ir->d.name, ir->d.minor);
347	return minor;
348
349	out_sysfs:
350	device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
351	out_lock:
352	mutex_unlock(&lirc_dev_lock);
353	out:
354	return err;
355	}
356	EXPORT_SYMBOL(lirc_register_driver);
357
358	int lirc_unregister_driver(int minor)
359	{
360	struct irctl *ir;
361
362	if (minor < 0 \|\| minor >= MAX_IRCTL_DEVICES) {
363	printk(KERN_ERR "lirc_dev: lirc_unregister_driver: "
364	"\"minor (%d)\" must be between 0 and %d!\n",
365	minor, MAX_IRCTL_DEVICES-1);
366	return -EBADRQC;
367	}
368
369	ir = irctls[minor];
370
371	mutex_lock(&lirc_dev_lock);
372
373	if (ir->d.minor != minor) {
374	printk(KERN_ERR "lirc_dev: lirc_unregister_driver: "
375	"minor (%d) device not registered!", minor);
376	mutex_unlock(&lirc_dev_lock);
377	return -ENOENT;
378	}
379
380	/* end up polling thread */
381	if (ir->task)
382	kthread_stop(ir->task);
383
384	dev_dbg(ir->d.dev, "lirc_dev: driver %s unregistered from minor = %d\n",
385	ir->d.name, ir->d.minor);
386
387	ir->attached = 0;
388	if (ir->open) {
389	dev_dbg(ir->d.dev, LOGHEAD "releasing opened driver\n",
390	ir->d.name, ir->d.minor);
391	wake_up_interruptible(&ir->buf->wait_poll);
392	mutex_lock(&ir->irctl_lock);
393	ir->d.set_use_dec(ir->d.data);
394	module_put(ir->d.owner);
395	mutex_unlock(&ir->irctl_lock);
396	cdev_del(&ir->cdev);
397	} else {
398	cleanup(ir);
399	cdev_del(&ir->cdev);
400	kfree(ir);
401	irctls[minor] = NULL;
402	}
403
404	mutex_unlock(&lirc_dev_lock);
405
406	return 0;
407	}
408	EXPORT_SYMBOL(lirc_unregister_driver);
409
410	int lirc_dev_fop_open(struct inode inode, struct file file)
411	{
412	struct irctl *ir;
413	int retval = 0;
414
415	if (iminor(inode) >= MAX_IRCTL_DEVICES) {
416	printk(KERN_WARNING "lirc_dev [%d]: open result = -ENODEV\n",
417	iminor(inode));
418	return -ENODEV;
419	}
420
421	if (mutex_lock_interruptible(&lirc_dev_lock))
422	return -ERESTARTSYS;
423
424	ir = irctls[iminor(inode)];
425	if (!ir) {
426	retval = -ENODEV;
427	goto error;
428	}
044e5878	429	file->private_data = ir;
4a62a5ab JW	430
	431	dev_dbg(ir->d.dev, LOGHEAD "open called\n", ir->d.name, ir->d.minor);
	432
	433	if (ir->d.minor == NOPLUG) {
	434	retval = -ENODEV;
	435	goto error;
	436	}
	437
	438	if (ir->open) {
	439	retval = -EBUSY;
	440	goto error;
	441	}
	442
	443	if (try_module_get(ir->d.owner)) {
	444	++ir->open;
	445	retval = ir->d.set_use_inc(ir->d.data);
	446
	447	if (retval) {
	448	module_put(ir->d.owner);
	449	--ir->open;
	450	} else {
	451	lirc_buffer_clear(ir->buf);
	452	}
	453	if (ir->task)
	454	wake_up_process(ir->task);
	455	}
	456
	457	error:
	458	if (ir)
	459	dev_dbg(ir->d.dev, LOGHEAD "open result = %d\n",
	460	ir->d.name, ir->d.minor, retval);
	461
	462	mutex_unlock(&lirc_dev_lock);
	463
d9d2e9d5 AB	464	nonseekable_open(inode, file);
d9d2e9d5 AB	465
4a62a5ab JW	466	return retval;
	467	}
	468	EXPORT_SYMBOL(lirc_dev_fop_open);
	469
	470	int lirc_dev_fop_close(struct inode inode, struct file file)
	471	{
	472	struct irctl *ir = irctls[iminor(inode)];
	473
	474	dev_dbg(ir->d.dev, LOGHEAD "close called\n", ir->d.name, ir->d.minor);
	475
	476	WARN_ON(mutex_lock_killable(&lirc_dev_lock));
	477
	478	--ir->open;
	479	if (ir->attached) {
	480	ir->d.set_use_dec(ir->d.data);
	481	module_put(ir->d.owner);
	482	} else {
	483	cleanup(ir);
	484	irctls[ir->d.minor] = NULL;
	485	kfree(ir);
	486	}
	487
	488	mutex_unlock(&lirc_dev_lock);
	489
	490	return 0;
	491	}
	492	EXPORT_SYMBOL(lirc_dev_fop_close);
	493
	494	unsigned int lirc_dev_fop_poll(struct file file, poll_table wait)
	495	{
	496	struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
	497	unsigned int ret;
	498
	499	dev_dbg(ir->d.dev, LOGHEAD "poll called\n", ir->d.name, ir->d.minor);
	500
	501	if (!ir->attached) {
	502	mutex_unlock(&ir->irctl_lock);
	503	return POLLERR;
	504	}
	505
	506	poll_wait(file, &ir->buf->wait_poll, wait);
	507
	508	if (ir->buf)
	509	if (lirc_buffer_empty(ir->buf))
	510	ret = 0;
	511	else
	512	ret = POLLIN \| POLLRDNORM;
	513	else
	514	ret = POLLERR;
	515
	516	dev_dbg(ir->d.dev, LOGHEAD "poll result = %d\n",
	517	ir->d.name, ir->d.minor, ret);
	518
	519	return ret;
	520	}
	521	EXPORT_SYMBOL(lirc_dev_fop_poll);
	522
044e5878	523	long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
4a62a5ab JW	524	{
	525	unsigned long mode;
	526	int result = 0;
044e5878	527	struct irctl *ir = file->private_data;
4a62a5ab JW	528
	529	dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n",
	530	ir->d.name, ir->d.minor, cmd);
	531
	532	if (ir->d.minor == NOPLUG \|\| !ir->attached) {
	533	dev_dbg(ir->d.dev, LOGHEAD "ioctl result = -ENODEV\n",
	534	ir->d.name, ir->d.minor);
	535	return -ENODEV;
	536	}
	537
	538	mutex_lock(&ir->irctl_lock);
	539
	540	switch (cmd) {
	541	case LIRC_GET_FEATURES:
	542	result = put_user(ir->d.features, (unsigned long *)arg);
	543	break;
	544	case LIRC_GET_REC_MODE:
	545	if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
	546	result = -ENOSYS;
	547	break;
	548	}
	549
	550	result = put_user(LIRC_REC2MODE
	551	(ir->d.features & LIRC_CAN_REC_MASK),
	552	(unsigned long *)arg);
	553	break;
	554	case LIRC_SET_REC_MODE:
	555	if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
	556	result = -ENOSYS;
	557	break;
	558	}
	559
	560	result = get_user(mode, (unsigned long *)arg);
	561	if (!result && !(LIRC_MODE2REC(mode) & ir->d.features))
	562	result = -EINVAL;
	563	/*
	564	* FIXME: We should actually set the mode somehow but
	565	* for now, lirc_serial doesn't support mode changing either
	566	*/
	567	break;
	568	case LIRC_GET_LENGTH:
	569	result = put_user(ir->d.code_length, (unsigned long *)arg);
	570	break;
	571	case LIRC_GET_MIN_TIMEOUT:
	572	if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) \|\|
	573	ir->d.min_timeout == 0) {
	574	result = -ENOSYS;
	575	break;
	576	}
	577
	578	result = put_user(ir->d.min_timeout, (unsigned long *)arg);
	579	break;
	580	case LIRC_GET_MAX_TIMEOUT:
	581	if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) \|\|
	582	ir->d.max_timeout == 0) {
	583	result = -ENOSYS;
	584	break;
	585	}
	586
	587	result = put_user(ir->d.max_timeout, (unsigned long *)arg);
	588	break;
	589	default:
	590	result = -EINVAL;
	591	}
592
593	dev_dbg(ir->d.dev, LOGHEAD "ioctl result = %d\n",
594	ir->d.name, ir->d.minor, result);
595
596	mutex_unlock(&ir->irctl_lock);
597
598	return result;
599	}
600	EXPORT_SYMBOL(lirc_dev_fop_ioctl);
601
602	ssize_t lirc_dev_fop_read(struct file *file,
603	char *buffer,
604	size_t length,
605	loff_t *ppos)
606	{
607	struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
608	unsigned char buf[ir->chunk_size];
609	int ret = 0, written = 0;
610	DECLARE_WAITQUEUE(wait, current);
611
612	dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor);
613
614	if (mutex_lock_interruptible(&ir->irctl_lock))
615	return -ERESTARTSYS;
616	if (!ir->attached) {
617	mutex_unlock(&ir->irctl_lock);
618	return -ENODEV;
619	}
620
621	if (length % ir->chunk_size) {
622	dev_dbg(ir->d.dev, LOGHEAD "read result = -EINVAL\n",
623	ir->d.name, ir->d.minor);
624	mutex_unlock(&ir->irctl_lock);
625	return -EINVAL;
626	}
627
628	/*
629	* we add ourselves to the task queue before buffer check
630	* to avoid losing scan code (in case when queue is awaken somewhere
631	* between while condition checking and scheduling)
632	*/
633	add_wait_queue(&ir->buf->wait_poll, &wait);
634	set_current_state(TASK_INTERRUPTIBLE);
635
636	/*
637	* while we didn't provide 'length' bytes, device is opened in blocking
638	* mode and 'copy_to_user' is happy, wait for data.
639	*/
640	while (written < length && ret == 0) {
641	if (lirc_buffer_empty(ir->buf)) {
642	/* According to the read(2) man page, 'written' can be
643	* returned as less than 'length', instead of blocking
644	* again, returning -EWOULDBLOCK, or returning
645	* -ERESTARTSYS */
646	if (written)
647	break;
648	if (file->f_flags & O_NONBLOCK) {
649	ret = -EWOULDBLOCK;
650	break;
651	}
652	if (signal_pending(current)) {
653	ret = -ERESTARTSYS;
654	break;
655	}
656
657	mutex_unlock(&ir->irctl_lock);
658	schedule();
659	set_current_state(TASK_INTERRUPTIBLE);
660
661	if (mutex_lock_interruptible(&ir->irctl_lock)) {
662	ret = -ERESTARTSYS;
69c271f3 JW	663	remove_wait_queue(&ir->buf->wait_poll, &wait);
	664	set_current_state(TASK_RUNNING);
	665	goto out_unlocked;
4a62a5ab JW	666	}
	667
	668	if (!ir->attached) {
	669	ret = -ENODEV;
	670	break;
	671	}
	672	} else {
	673	lirc_buffer_read(ir->buf, buf);
	674	ret = copy_to_user((void *)buffer+written, buf,
	675	ir->buf->chunk_size);
	676	written += ir->buf->chunk_size;
	677	}
	678	}
	679
	680	remove_wait_queue(&ir->buf->wait_poll, &wait);
	681	set_current_state(TASK_RUNNING);
	682	mutex_unlock(&ir->irctl_lock);
	683
69c271f3	684	out_unlocked:
4a62a5ab JW	685	dev_dbg(ir->d.dev, LOGHEAD "read result = %s (%d)\n",
	686	ir->d.name, ir->d.minor, ret ? "-EFAULT" : "OK", ret);
	687
	688	return ret ? ret : written;
	689	}
	690	EXPORT_SYMBOL(lirc_dev_fop_read);
	691
	692	void lirc_get_pdata(struct file file)
	693	{
	694	void *data = NULL;
	695
	696	if (file && file->f_dentry && file->f_dentry->d_inode &&
	697	file->f_dentry->d_inode->i_rdev) {
	698	struct irctl *ir;
	699	ir = irctls[iminor(file->f_dentry->d_inode)];
	700	data = ir->d.data;
	701	}
	702
	703	return data;
	704	}
	705	EXPORT_SYMBOL(lirc_get_pdata);
	706
	707
	708	ssize_t lirc_dev_fop_write(struct file file, const char buffer,
	709	size_t length, loff_t *ppos)
	710	{
	711	struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
	712
	713	dev_dbg(ir->d.dev, LOGHEAD "write called\n", ir->d.name, ir->d.minor);
	714
	715	if (!ir->attached)
	716	return -ENODEV;
	717
	718	return -EINVAL;
	719	}
	720	EXPORT_SYMBOL(lirc_dev_fop_write);
	721
	722
	723	static int __init lirc_dev_init(void)
	724	{
	725	int retval;
	726
	727	lirc_class = class_create(THIS_MODULE, "lirc");
	728	if (IS_ERR(lirc_class)) {
	729	retval = PTR_ERR(lirc_class);
	730	printk(KERN_ERR "lirc_dev: class_create failed\n");
	731	goto error;
	732	}
	733
	734	retval = alloc_chrdev_region(&lirc_base_dev, 0, MAX_IRCTL_DEVICES,
	735	IRCTL_DEV_NAME);
	736	if (retval) {
	737	class_destroy(lirc_class);
	738	printk(KERN_ERR "lirc_dev: alloc_chrdev_region failed\n");
	739	goto error;
	740	}
	741
	742
	743	printk(KERN_INFO "lirc_dev: IR Remote Control driver registered, "
	744	"major %d \n", MAJOR(lirc_base_dev));
	745
	746	error:
	747	return retval;
	748	}
749
750
751
752	static void __exit lirc_dev_exit(void)
753	{
754	class_destroy(lirc_class);
755	unregister_chrdev_region(lirc_base_dev, MAX_IRCTL_DEVICES);
756	printk(KERN_INFO "lirc_dev: module unloaded\n");
757	}
758
759	module_init(lirc_dev_init);
760	module_exit(lirc_dev_exit);
761
762	MODULE_DESCRIPTION("LIRC base driver module");
763	MODULE_AUTHOR("Artur Lipowski");
764	MODULE_LICENSE("GPL");
765
766	module_param(debug, bool, S_IRUGO \| S_IWUSR);
767	MODULE_PARM_DESC(debug, "Enable debugging messages");