4 * by Artur Lipowski <alipowski@interia.pl>
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.
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.
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
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>
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>
39 #include <media/lirc.h>
40 #include <media/lirc_dev.h>
44 #define IRCTL_DEV_NAME "BaseRemoteCtl"
46 #define LOGHEAD "lirc_dev (%s[%d]): "
48 static dev_t lirc_base_dev;
55 struct mutex irctl_lock;
56 struct lirc_buffer *buf;
57 unsigned int chunk_size;
59 struct task_struct *task;
65 static DEFINE_MUTEX(lirc_dev_lock);
67 static struct irctl *irctls[MAX_IRCTL_DEVICES];
69 /* Only used for sysfs but defined to void otherwise */
70 static struct class *lirc_class;
73 * initializes the irctl structure
75 static void init_irctl(struct irctl *ir)
77 dev_dbg(ir->d.dev, LOGHEAD "initializing irctl\n",
78 ir->d.name, ir->d.minor);
79 mutex_init(&ir->irctl_lock);
83 static void cleanup(struct irctl *ir)
85 dev_dbg(ir->d.dev, LOGHEAD "cleaning up\n", ir->d.name, ir->d.minor);
87 device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
89 if (ir->buf != ir->d.rbuf) {
90 lirc_buffer_free(ir->buf);
97 * reads key codes from driver and puts them into buffer
98 * returns 0 on success
100 static int add_to_buf(struct irctl *ir)
102 if (ir->d.add_to_buf) {
107 * service the device as long as it is returning
108 * data and we have space
111 res = ir->d.add_to_buf(ir->d.data, ir->buf);
118 kthread_stop(ir->task);
120 return got_data ? 0 : res;
126 /* main function of the polling thread
128 static int lirc_thread(void *irctl)
130 struct irctl *ir = irctl;
132 dev_dbg(ir->d.dev, LOGHEAD "poll thread started\n",
133 ir->d.name, ir->d.minor);
137 if (ir->jiffies_to_wait) {
138 set_current_state(TASK_INTERRUPTIBLE);
139 schedule_timeout(ir->jiffies_to_wait);
141 if (kthread_should_stop())
144 wake_up_interruptible(&ir->buf->wait_poll);
146 set_current_state(TASK_INTERRUPTIBLE);
149 } while (!kthread_should_stop());
151 dev_dbg(ir->d.dev, LOGHEAD "poll thread ended\n",
152 ir->d.name, ir->d.minor);
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,
163 .unlocked_ioctl = lirc_dev_fop_ioctl,
164 .open = lirc_dev_fop_open,
165 .release = lirc_dev_fop_close,
166 .llseek = noop_llseek,
169 static int lirc_cdev_add(struct irctl *ir)
172 struct lirc_driver *d = &ir->d;
175 cdev_init(&ir->cdev, d->fops);
176 ir->cdev.owner = d->owner;
178 cdev_init(&ir->cdev, &fops);
179 ir->cdev.owner = THIS_MODULE;
181 kobject_set_name(&ir->cdev.kobj, "lirc%d", d->minor);
183 retval = cdev_add(&ir->cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
185 kobject_put(&ir->cdev.kobj);
190 int lirc_register_driver(struct lirc_driver *d)
195 unsigned int chunk_size;
196 unsigned int buffer_size;
200 printk(KERN_ERR "lirc_dev: lirc_register_driver: "
201 "driver pointer must be not NULL!\n");
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);
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);
223 dev_dbg(d->dev, "lirc_dev: lirc_register_driver: sample_rate: %d\n",
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);
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");
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");
244 } else if (!d->rbuf) {
245 if (!(d->fops && d->fops->read && d->fops->poll &&
246 d->fops->unlocked_ioctl)) {
247 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
248 "neither read, poll nor unlocked_ioctl can be NULL!\n");
254 mutex_lock(&lirc_dev_lock);
259 /* find first free slot for driver */
260 for (minor = 0; minor < MAX_IRCTL_DEVICES; minor++)
263 if (MAX_IRCTL_DEVICES == minor) {
264 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
265 "no free slots for drivers!\n");
269 } else if (irctls[minor]) {
270 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
271 "minor (%d) just registered!\n", minor);
276 ir = kzalloc(sizeof(struct irctl), GFP_KERNEL);
285 if (d->sample_rate) {
286 ir->jiffies_to_wait = HZ / d->sample_rate;
288 /* it means - wait for external event in task queue */
289 ir->jiffies_to_wait = 0;
292 /* some safety check 8-) */
293 d->name[sizeof(d->name)-1] = '\0';
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;
303 ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
308 err = lirc_buffer_init(ir->buf, chunk_size, buffer_size);
314 ir->chunk_size = ir->buf->chunk_size;
316 if (d->features == 0)
317 d->features = LIRC_CAN_REC_LIRCCODE;
322 device_create(lirc_class, ir->d.dev,
323 MKDEV(MAJOR(lirc_base_dev), ir->d.minor), NULL,
324 "lirc%u", ir->d.minor);
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",
338 err = lirc_cdev_add(ir);
343 mutex_unlock(&lirc_dev_lock);
345 dev_info(ir->d.dev, "lirc_dev: driver %s registered at minor = %d\n",
346 ir->d.name, ir->d.minor);
350 device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
352 mutex_unlock(&lirc_dev_lock);
356 EXPORT_SYMBOL(lirc_register_driver);
358 int lirc_unregister_driver(int minor)
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);
371 mutex_lock(&lirc_dev_lock);
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);
380 /* end up polling thread */
382 kthread_stop(ir->task);
384 dev_dbg(ir->d.dev, "lirc_dev: driver %s unregistered from minor = %d\n",
385 ir->d.name, ir->d.minor);
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);
401 irctls[minor] = NULL;
404 mutex_unlock(&lirc_dev_lock);
408 EXPORT_SYMBOL(lirc_unregister_driver);
410 int lirc_dev_fop_open(struct inode *inode, struct file *file)
415 if (iminor(inode) >= MAX_IRCTL_DEVICES) {
416 printk(KERN_WARNING "lirc_dev [%d]: open result = -ENODEV\n",
421 if (mutex_lock_interruptible(&lirc_dev_lock))
424 ir = irctls[iminor(inode)];
429 file->private_data = ir;
431 dev_dbg(ir->d.dev, LOGHEAD "open called\n", ir->d.name, ir->d.minor);
433 if (ir->d.minor == NOPLUG) {
443 if (try_module_get(ir->d.owner)) {
445 retval = ir->d.set_use_inc(ir->d.data);
448 module_put(ir->d.owner);
451 lirc_buffer_clear(ir->buf);
454 wake_up_process(ir->task);
459 dev_dbg(ir->d.dev, LOGHEAD "open result = %d\n",
460 ir->d.name, ir->d.minor, retval);
462 mutex_unlock(&lirc_dev_lock);
464 nonseekable_open(inode, file);
468 EXPORT_SYMBOL(lirc_dev_fop_open);
470 int lirc_dev_fop_close(struct inode *inode, struct file *file)
472 struct irctl *ir = irctls[iminor(inode)];
474 dev_dbg(ir->d.dev, LOGHEAD "close called\n", ir->d.name, ir->d.minor);
476 WARN_ON(mutex_lock_killable(&lirc_dev_lock));
480 ir->d.set_use_dec(ir->d.data);
481 module_put(ir->d.owner);
484 irctls[ir->d.minor] = NULL;
488 mutex_unlock(&lirc_dev_lock);
492 EXPORT_SYMBOL(lirc_dev_fop_close);
494 unsigned int lirc_dev_fop_poll(struct file *file, poll_table *wait)
496 struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
499 dev_dbg(ir->d.dev, LOGHEAD "poll called\n", ir->d.name, ir->d.minor);
502 mutex_unlock(&ir->irctl_lock);
506 poll_wait(file, &ir->buf->wait_poll, wait);
509 if (lirc_buffer_empty(ir->buf))
512 ret = POLLIN | POLLRDNORM;
516 dev_dbg(ir->d.dev, LOGHEAD "poll result = %d\n",
517 ir->d.name, ir->d.minor, ret);
521 EXPORT_SYMBOL(lirc_dev_fop_poll);
523 long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
527 struct irctl *ir = file->private_data;
529 dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n",
530 ir->d.name, ir->d.minor, cmd);
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);
538 mutex_lock(&ir->irctl_lock);
541 case LIRC_GET_FEATURES:
542 result = put_user(ir->d.features, (unsigned long *)arg);
544 case LIRC_GET_REC_MODE:
545 if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
550 result = put_user(LIRC_REC2MODE
551 (ir->d.features & LIRC_CAN_REC_MASK),
552 (unsigned long *)arg);
554 case LIRC_SET_REC_MODE:
555 if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
560 result = get_user(mode, (unsigned long *)arg);
561 if (!result && !(LIRC_MODE2REC(mode) & ir->d.features))
564 * FIXME: We should actually set the mode somehow but
565 * for now, lirc_serial doesn't support mode changing either
568 case LIRC_GET_LENGTH:
569 result = put_user(ir->d.code_length, (unsigned long *)arg);
571 case LIRC_GET_MIN_TIMEOUT:
572 if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
573 ir->d.min_timeout == 0) {
578 result = put_user(ir->d.min_timeout, (unsigned long *)arg);
580 case LIRC_GET_MAX_TIMEOUT:
581 if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
582 ir->d.max_timeout == 0) {
587 result = put_user(ir->d.max_timeout, (unsigned long *)arg);
593 dev_dbg(ir->d.dev, LOGHEAD "ioctl result = %d\n",
594 ir->d.name, ir->d.minor, result);
596 mutex_unlock(&ir->irctl_lock);
600 EXPORT_SYMBOL(lirc_dev_fop_ioctl);
602 ssize_t lirc_dev_fop_read(struct file *file,
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);
612 dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor);
614 if (mutex_lock_interruptible(&ir->irctl_lock))
617 mutex_unlock(&ir->irctl_lock);
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);
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)
633 add_wait_queue(&ir->buf->wait_poll, &wait);
634 set_current_state(TASK_INTERRUPTIBLE);
637 * while we didn't provide 'length' bytes, device is opened in blocking
638 * mode and 'copy_to_user' is happy, wait for data.
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
648 if (file->f_flags & O_NONBLOCK) {
652 if (signal_pending(current)) {
657 mutex_unlock(&ir->irctl_lock);
659 set_current_state(TASK_INTERRUPTIBLE);
661 if (mutex_lock_interruptible(&ir->irctl_lock)) {
663 remove_wait_queue(&ir->buf->wait_poll, &wait);
664 set_current_state(TASK_RUNNING);
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;
680 remove_wait_queue(&ir->buf->wait_poll, &wait);
681 set_current_state(TASK_RUNNING);
682 mutex_unlock(&ir->irctl_lock);
685 dev_dbg(ir->d.dev, LOGHEAD "read result = %s (%d)\n",
686 ir->d.name, ir->d.minor, ret ? "-EFAULT" : "OK", ret);
688 return ret ? ret : written;
690 EXPORT_SYMBOL(lirc_dev_fop_read);
692 void *lirc_get_pdata(struct file *file)
696 if (file && file->f_dentry && file->f_dentry->d_inode &&
697 file->f_dentry->d_inode->i_rdev) {
699 ir = irctls[iminor(file->f_dentry->d_inode)];
705 EXPORT_SYMBOL(lirc_get_pdata);
708 ssize_t lirc_dev_fop_write(struct file *file, const char *buffer,
709 size_t length, loff_t *ppos)
711 struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
713 dev_dbg(ir->d.dev, LOGHEAD "write called\n", ir->d.name, ir->d.minor);
720 EXPORT_SYMBOL(lirc_dev_fop_write);
723 static int __init lirc_dev_init(void)
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");
734 retval = alloc_chrdev_region(&lirc_base_dev, 0, MAX_IRCTL_DEVICES,
737 class_destroy(lirc_class);
738 printk(KERN_ERR "lirc_dev: alloc_chrdev_region failed\n");
743 printk(KERN_INFO "lirc_dev: IR Remote Control driver registered, "
744 "major %d \n", MAJOR(lirc_base_dev));
752 static void __exit lirc_dev_exit(void)
754 class_destroy(lirc_class);
755 unregister_chrdev_region(lirc_base_dev, MAX_IRCTL_DEVICES);
756 printk(KERN_INFO "lirc_dev: module unloaded\n");
759 module_init(lirc_dev_init);
760 module_exit(lirc_dev_exit);
762 MODULE_DESCRIPTION("LIRC base driver module");
763 MODULE_AUTHOR("Artur Lipowski");
764 MODULE_LICENSE("GPL");
766 module_param(debug, bool, S_IRUGO | S_IWUSR);
767 MODULE_PARM_DESC(debug, "Enable debugging messages");