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/mutex.h>
31 #include <linux/wait.h>
32 #include <linux/unistd.h>
33 #include <linux/kthread.h>
34 #include <linux/bitops.h>
35 #include <linux/device.h>
36 #include <linux/cdev.h>
38 #include <media/lirc.h>
39 #include <media/lirc_dev.h>
43 #define IRCTL_DEV_NAME "BaseRemoteCtl"
45 #define LOGHEAD "lirc_dev (%s[%d]): "
47 static dev_t lirc_base_dev;
54 struct mutex irctl_lock;
55 struct lirc_buffer *buf;
56 unsigned int chunk_size;
58 struct task_struct *task;
62 static DEFINE_MUTEX(lirc_dev_lock);
64 static struct irctl *irctls[MAX_IRCTL_DEVICES];
65 static struct cdev cdevs[MAX_IRCTL_DEVICES];
67 /* Only used for sysfs but defined to void otherwise */
68 static struct class *lirc_class;
71 * initializes the irctl structure
73 static void lirc_irctl_init(struct irctl *ir)
75 mutex_init(&ir->irctl_lock);
79 static void lirc_irctl_cleanup(struct irctl *ir)
81 dev_dbg(ir->d.dev, LOGHEAD "cleaning up\n", ir->d.name, ir->d.minor);
83 device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
85 if (ir->buf != ir->d.rbuf) {
86 lirc_buffer_free(ir->buf);
93 * reads key codes from driver and puts them into buffer
94 * returns 0 on success
96 static int lirc_add_to_buf(struct irctl *ir)
98 if (ir->d.add_to_buf) {
103 * service the device as long as it is returning
104 * data and we have space
107 res = ir->d.add_to_buf(ir->d.data, ir->buf);
114 kthread_stop(ir->task);
116 return got_data ? 0 : res;
122 /* main function of the polling thread
124 static int lirc_thread(void *irctl)
126 struct irctl *ir = irctl;
128 dev_dbg(ir->d.dev, LOGHEAD "poll thread started\n",
129 ir->d.name, ir->d.minor);
133 if (ir->jiffies_to_wait) {
134 set_current_state(TASK_INTERRUPTIBLE);
135 schedule_timeout(ir->jiffies_to_wait);
137 if (kthread_should_stop())
139 if (!lirc_add_to_buf(ir))
140 wake_up_interruptible(&ir->buf->wait_poll);
142 set_current_state(TASK_INTERRUPTIBLE);
145 } while (!kthread_should_stop());
147 dev_dbg(ir->d.dev, LOGHEAD "poll thread ended\n",
148 ir->d.name, ir->d.minor);
154 static struct file_operations lirc_dev_fops = {
155 .owner = THIS_MODULE,
156 .read = lirc_dev_fop_read,
157 .write = lirc_dev_fop_write,
158 .poll = lirc_dev_fop_poll,
159 .unlocked_ioctl = lirc_dev_fop_ioctl,
161 .compat_ioctl = lirc_dev_fop_ioctl,
163 .open = lirc_dev_fop_open,
164 .release = lirc_dev_fop_close,
165 .llseek = noop_llseek,
168 static int lirc_cdev_add(struct irctl *ir)
171 struct lirc_driver *d = &ir->d;
172 struct cdev *cdev = &cdevs[d->minor];
175 cdev_init(cdev, d->fops);
176 cdev->owner = d->owner;
178 cdev_init(cdev, &lirc_dev_fops);
179 cdev->owner = THIS_MODULE;
181 kobject_set_name(&cdev->kobj, "lirc%d", d->minor);
183 retval = cdev_add(cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
185 kobject_put(&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");
207 printk(KERN_ERR "%s: dev pointer not filled in!\n", __func__);
212 if (MAX_IRCTL_DEVICES <= d->minor) {
213 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
214 "\"minor\" must be between 0 and %d (%d)!\n",
215 MAX_IRCTL_DEVICES-1, d->minor);
220 if (1 > d->code_length || (BUFLEN * 8) < d->code_length) {
221 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
222 "code length in bits for minor (%d) "
223 "must be less than %d!\n",
224 d->minor, BUFLEN * 8);
229 dev_dbg(d->dev, "lirc_dev: lirc_register_driver: sample_rate: %d\n",
231 if (d->sample_rate) {
232 if (2 > d->sample_rate || HZ < d->sample_rate) {
233 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
234 "sample_rate must be between 2 and %d!\n", HZ);
238 if (!d->add_to_buf) {
239 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
240 "add_to_buf cannot be NULL when "
241 "sample_rate is set\n");
245 } else if (!(d->fops && d->fops->read) && !d->rbuf) {
246 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
247 "fops->read and rbuf cannot all be NULL!\n");
250 } else if (!d->rbuf) {
251 if (!(d->fops && d->fops->read && d->fops->poll &&
252 d->fops->unlocked_ioctl)) {
253 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
254 "neither read, poll nor unlocked_ioctl can be NULL!\n");
260 mutex_lock(&lirc_dev_lock);
265 /* find first free slot for driver */
266 for (minor = 0; minor < MAX_IRCTL_DEVICES; minor++)
269 if (MAX_IRCTL_DEVICES == minor) {
270 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
271 "no free slots for drivers!\n");
275 } else if (irctls[minor]) {
276 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
277 "minor (%d) just registered!\n", minor);
282 ir = kzalloc(sizeof(struct irctl), GFP_KERNEL);
291 if (d->sample_rate) {
292 ir->jiffies_to_wait = HZ / d->sample_rate;
294 /* it means - wait for external event in task queue */
295 ir->jiffies_to_wait = 0;
298 /* some safety check 8-) */
299 d->name[sizeof(d->name)-1] = '\0';
301 bytes_in_key = BITS_TO_LONGS(d->code_length) +
302 (d->code_length % 8 ? 1 : 0);
303 buffer_size = d->buffer_size ? d->buffer_size : BUFLEN / bytes_in_key;
304 chunk_size = d->chunk_size ? d->chunk_size : bytes_in_key;
309 ir->buf = kmalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
314 err = lirc_buffer_init(ir->buf, chunk_size, buffer_size);
320 ir->chunk_size = ir->buf->chunk_size;
322 if (d->features == 0)
323 d->features = LIRC_CAN_REC_LIRCCODE;
327 device_create(lirc_class, ir->d.dev,
328 MKDEV(MAJOR(lirc_base_dev), ir->d.minor), NULL,
329 "lirc%u", ir->d.minor);
331 if (d->sample_rate) {
332 /* try to fire up polling thread */
333 ir->task = kthread_run(lirc_thread, (void *)ir, "lirc_dev");
334 if (IS_ERR(ir->task)) {
335 dev_err(d->dev, "lirc_dev: lirc_register_driver: "
336 "cannot run poll thread for minor = %d\n",
343 err = lirc_cdev_add(ir);
348 mutex_unlock(&lirc_dev_lock);
350 dev_info(ir->d.dev, "lirc_dev: driver %s registered at minor = %d\n",
351 ir->d.name, ir->d.minor);
355 device_destroy(lirc_class, MKDEV(MAJOR(lirc_base_dev), ir->d.minor));
357 mutex_unlock(&lirc_dev_lock);
361 EXPORT_SYMBOL(lirc_register_driver);
363 int lirc_unregister_driver(int minor)
368 if (minor < 0 || minor >= MAX_IRCTL_DEVICES) {
369 printk(KERN_ERR "lirc_dev: %s: minor (%d) must be between "
370 "0 and %d!\n", __func__, minor, MAX_IRCTL_DEVICES-1);
376 printk(KERN_ERR "lirc_dev: %s: failed to get irctl struct "
377 "for minor %d!\n", __func__, minor);
381 cdev = &cdevs[minor];
383 mutex_lock(&lirc_dev_lock);
385 if (ir->d.minor != minor) {
386 printk(KERN_ERR "lirc_dev: %s: minor (%d) device not "
387 "registered!\n", __func__, minor);
388 mutex_unlock(&lirc_dev_lock);
392 /* end up polling thread */
394 kthread_stop(ir->task);
396 dev_dbg(ir->d.dev, "lirc_dev: driver %s unregistered from minor = %d\n",
397 ir->d.name, ir->d.minor);
401 dev_dbg(ir->d.dev, LOGHEAD "releasing opened driver\n",
402 ir->d.name, ir->d.minor);
403 wake_up_interruptible(&ir->buf->wait_poll);
404 mutex_lock(&ir->irctl_lock);
405 ir->d.set_use_dec(ir->d.data);
406 module_put(cdev->owner);
407 mutex_unlock(&ir->irctl_lock);
409 lirc_irctl_cleanup(ir);
412 irctls[minor] = NULL;
415 mutex_unlock(&lirc_dev_lock);
419 EXPORT_SYMBOL(lirc_unregister_driver);
421 int lirc_dev_fop_open(struct inode *inode, struct file *file)
427 if (iminor(inode) >= MAX_IRCTL_DEVICES) {
428 printk(KERN_WARNING "lirc_dev [%d]: open result = -ENODEV\n",
433 if (mutex_lock_interruptible(&lirc_dev_lock))
436 ir = irctls[iminor(inode)];
442 dev_dbg(ir->d.dev, LOGHEAD "open called\n", ir->d.name, ir->d.minor);
444 if (ir->d.minor == NOPLUG) {
454 cdev = &cdevs[iminor(inode)];
455 if (try_module_get(cdev->owner)) {
457 retval = ir->d.set_use_inc(ir->d.data);
460 module_put(cdev->owner);
463 lirc_buffer_clear(ir->buf);
466 wake_up_process(ir->task);
471 dev_dbg(ir->d.dev, LOGHEAD "open result = %d\n",
472 ir->d.name, ir->d.minor, retval);
474 mutex_unlock(&lirc_dev_lock);
476 nonseekable_open(inode, file);
480 EXPORT_SYMBOL(lirc_dev_fop_open);
482 int lirc_dev_fop_close(struct inode *inode, struct file *file)
484 struct irctl *ir = irctls[iminor(inode)];
485 struct cdev *cdev = &cdevs[iminor(inode)];
488 printk(KERN_ERR "%s: called with invalid irctl\n", __func__);
492 dev_dbg(ir->d.dev, LOGHEAD "close called\n", ir->d.name, ir->d.minor);
494 WARN_ON(mutex_lock_killable(&lirc_dev_lock));
498 ir->d.set_use_dec(ir->d.data);
499 module_put(cdev->owner);
501 lirc_irctl_cleanup(ir);
503 irctls[ir->d.minor] = NULL;
507 mutex_unlock(&lirc_dev_lock);
511 EXPORT_SYMBOL(lirc_dev_fop_close);
513 unsigned int lirc_dev_fop_poll(struct file *file, poll_table *wait)
515 struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
519 printk(KERN_ERR "%s: called with invalid irctl\n", __func__);
523 dev_dbg(ir->d.dev, LOGHEAD "poll called\n", ir->d.name, ir->d.minor);
528 poll_wait(file, &ir->buf->wait_poll, wait);
531 if (lirc_buffer_empty(ir->buf))
534 ret = POLLIN | POLLRDNORM;
538 dev_dbg(ir->d.dev, LOGHEAD "poll result = %d\n",
539 ir->d.name, ir->d.minor, ret);
543 EXPORT_SYMBOL(lirc_dev_fop_poll);
545 long lirc_dev_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
549 struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
552 printk(KERN_ERR "lirc_dev: %s: no irctl found!\n", __func__);
556 dev_dbg(ir->d.dev, LOGHEAD "ioctl called (0x%x)\n",
557 ir->d.name, ir->d.minor, cmd);
559 if (ir->d.minor == NOPLUG || !ir->attached) {
560 dev_dbg(ir->d.dev, LOGHEAD "ioctl result = -ENODEV\n",
561 ir->d.name, ir->d.minor);
565 mutex_lock(&ir->irctl_lock);
568 case LIRC_GET_FEATURES:
569 result = put_user(ir->d.features, (__u32 *)arg);
571 case LIRC_GET_REC_MODE:
572 if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
577 result = put_user(LIRC_REC2MODE
578 (ir->d.features & LIRC_CAN_REC_MASK),
581 case LIRC_SET_REC_MODE:
582 if (!(ir->d.features & LIRC_CAN_REC_MASK)) {
587 result = get_user(mode, (__u32 *)arg);
588 if (!result && !(LIRC_MODE2REC(mode) & ir->d.features))
591 * FIXME: We should actually set the mode somehow but
592 * for now, lirc_serial doesn't support mode changing either
595 case LIRC_GET_LENGTH:
596 result = put_user(ir->d.code_length, (__u32 *)arg);
598 case LIRC_GET_MIN_TIMEOUT:
599 if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
600 ir->d.min_timeout == 0) {
605 result = put_user(ir->d.min_timeout, (__u32 *)arg);
607 case LIRC_GET_MAX_TIMEOUT:
608 if (!(ir->d.features & LIRC_CAN_SET_REC_TIMEOUT) ||
609 ir->d.max_timeout == 0) {
614 result = put_user(ir->d.max_timeout, (__u32 *)arg);
620 dev_dbg(ir->d.dev, LOGHEAD "ioctl result = %d\n",
621 ir->d.name, ir->d.minor, result);
623 mutex_unlock(&ir->irctl_lock);
627 EXPORT_SYMBOL(lirc_dev_fop_ioctl);
629 ssize_t lirc_dev_fop_read(struct file *file,
634 struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
636 int ret = 0, written = 0;
637 DECLARE_WAITQUEUE(wait, current);
640 printk(KERN_ERR "%s: called with invalid irctl\n", __func__);
644 dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor);
646 buf = kzalloc(ir->chunk_size, GFP_KERNEL);
650 if (mutex_lock_interruptible(&ir->irctl_lock)) {
659 if (length % ir->chunk_size) {
665 * we add ourselves to the task queue before buffer check
666 * to avoid losing scan code (in case when queue is awaken somewhere
667 * between while condition checking and scheduling)
669 add_wait_queue(&ir->buf->wait_poll, &wait);
670 set_current_state(TASK_INTERRUPTIBLE);
673 * while we didn't provide 'length' bytes, device is opened in blocking
674 * mode and 'copy_to_user' is happy, wait for data.
676 while (written < length && ret == 0) {
677 if (lirc_buffer_empty(ir->buf)) {
678 /* According to the read(2) man page, 'written' can be
679 * returned as less than 'length', instead of blocking
680 * again, returning -EWOULDBLOCK, or returning
684 if (file->f_flags & O_NONBLOCK) {
688 if (signal_pending(current)) {
693 mutex_unlock(&ir->irctl_lock);
695 set_current_state(TASK_INTERRUPTIBLE);
697 if (mutex_lock_interruptible(&ir->irctl_lock)) {
699 remove_wait_queue(&ir->buf->wait_poll, &wait);
700 set_current_state(TASK_RUNNING);
709 lirc_buffer_read(ir->buf, buf);
710 ret = copy_to_user((void *)buffer+written, buf,
711 ir->buf->chunk_size);
713 written += ir->buf->chunk_size;
719 remove_wait_queue(&ir->buf->wait_poll, &wait);
720 set_current_state(TASK_RUNNING);
723 mutex_unlock(&ir->irctl_lock);
727 dev_dbg(ir->d.dev, LOGHEAD "read result = %s (%d)\n",
728 ir->d.name, ir->d.minor, ret ? "<fail>" : "<ok>", ret);
730 return ret ? ret : written;
732 EXPORT_SYMBOL(lirc_dev_fop_read);
734 void *lirc_get_pdata(struct file *file)
738 if (file && file->f_dentry && file->f_dentry->d_inode &&
739 file->f_dentry->d_inode->i_rdev) {
741 ir = irctls[iminor(file->f_dentry->d_inode)];
747 EXPORT_SYMBOL(lirc_get_pdata);
750 ssize_t lirc_dev_fop_write(struct file *file, const char __user *buffer,
751 size_t length, loff_t *ppos)
753 struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)];
756 printk(KERN_ERR "%s: called with invalid irctl\n", __func__);
760 dev_dbg(ir->d.dev, LOGHEAD "write called\n", ir->d.name, ir->d.minor);
767 EXPORT_SYMBOL(lirc_dev_fop_write);
770 static int __init lirc_dev_init(void)
774 lirc_class = class_create(THIS_MODULE, "lirc");
775 if (IS_ERR(lirc_class)) {
776 retval = PTR_ERR(lirc_class);
777 printk(KERN_ERR "lirc_dev: class_create failed\n");
781 retval = alloc_chrdev_region(&lirc_base_dev, 0, MAX_IRCTL_DEVICES,
784 class_destroy(lirc_class);
785 printk(KERN_ERR "lirc_dev: alloc_chrdev_region failed\n");
790 printk(KERN_INFO "lirc_dev: IR Remote Control driver registered, "
791 "major %d \n", MAJOR(lirc_base_dev));
799 static void __exit lirc_dev_exit(void)
801 class_destroy(lirc_class);
802 unregister_chrdev_region(lirc_base_dev, MAX_IRCTL_DEVICES);
803 printk(KERN_INFO "lirc_dev: module unloaded\n");
806 module_init(lirc_dev_init);
807 module_exit(lirc_dev_exit);
809 MODULE_DESCRIPTION("LIRC base driver module");
810 MODULE_AUTHOR("Artur Lipowski");
811 MODULE_LICENSE("GPL");
813 module_param(debug, bool, S_IRUGO | S_IWUSR);
814 MODULE_PARM_DESC(debug, "Enable debugging messages");