diff options
Diffstat (limited to 'drivers/media/rc/lirc_dev.c')
| -rw-r--r-- | drivers/media/rc/lirc_dev.c | 816 |
1 files changed, 816 insertions, 0 deletions
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c new file mode 100644 index 000000000000..fd237ab120bb --- /dev/null +++ b/drivers/media/rc/lirc_dev.c @@ -0,0 +1,816 @@ +/* + * 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/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; +}; + +static DEFINE_MUTEX(lirc_dev_lock); + +static struct irctl *irctls[MAX_IRCTL_DEVICES]; +static struct cdev cdevs[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 lirc_irctl_init(struct irctl *ir) +{ + mutex_init(&ir->irctl_lock); + ir->d.minor = NOPLUG; +} + +static void lirc_irctl_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 lirc_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 (!lirc_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 lirc_dev_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, +#ifdef CONFIG_COMPAT + .compat_ioctl = lirc_dev_fop_ioctl, +#endif + .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; + struct cdev *cdev = &cdevs[d->minor]; + + if (d->fops) { + cdev_init(cdev, d->fops); + cdev->owner = d->owner; + } else { + cdev_init(cdev, &lirc_dev_fops); + cdev->owner = THIS_MODULE; + } + retval = kobject_set_name(&cdev->kobj, "lirc%d", d->minor); + if (retval) + return retval; + + retval = cdev_add(cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1); + if (retval) + kobject_put(&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 (!d->dev) { + printk(KERN_ERR "%s: dev pointer not filled in!\n", __func__); + err = -EINVAL; + 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; + } + lirc_irctl_init(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; + + 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; + struct cdev *cdev; + + if (minor < 0 || minor >= MAX_IRCTL_DEVICES) { + printk(KERN_ERR "lirc_dev: %s: minor (%d) must be between " + "0 and %d!\n", __func__, minor, MAX_IRCTL_DEVICES-1); + return -EBADRQC; + } + + ir = irctls[minor]; + if (!ir) { + printk(KERN_ERR "lirc_dev: %s: failed to get irctl struct " + "for minor %d!\n", __func__, minor); + return -ENOENT; + } + + cdev = &cdevs[minor]; + + mutex_lock(&lirc_dev_lock); + + if (ir->d.minor != minor) { + printk(KERN_ERR "lirc_dev: %s: minor (%d) device not " + "registered!\n", __func__, 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(cdev->owner); + mutex_unlock(&ir->irctl_lock); + } else { + lirc_irctl_cleanup(ir); + cdev_del(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; + struct cdev *cdev; + 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; + } + + 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; + } + + cdev = &cdevs[iminor(inode)]; + if (try_module_get(cdev->owner)) { + ir->open++; + retval = ir->d.set_use_inc(ir->d.data); + + if (retval) { + module_put(cdev->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)]; + struct cdev *cdev = &cdevs[iminor(inode)]; + + if (!ir) { + printk(KERN_ERR "%s: called with invalid irctl\n", __func__); + return -EINVAL; + } + + 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(cdev->owner); + } else { + lirc_irctl_cleanup(ir); + cdev_del(cdev); + 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; + + if (!ir) { + printk(KERN_ERR "%s: called with invalid irctl\n", __func__); + return POLLERR; + } + + dev_dbg(ir->d.dev, LOGHEAD "poll called\n", ir->d.name, ir->d.minor); + + if (!ir->attached) + 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) +{ + __u32 mode; + int result = 0; + struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)]; + + if (!ir) { + printk(KERN_ERR "lirc_dev: %s: no irctl found!\n", __func__); + return -ENODEV; + } + + 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, (__u32 *)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), + (__u32 *)arg); + break; + case LIRC_SET_REC_MODE: + if (!(ir->d.features & LIRC_CAN_REC_MASK)) { + result = -ENOSYS; + break; + } + + result = get_user(mode, (__u32 *)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, (__u32 *)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, (__u32 *)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, (__u32 *)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 __user *buffer, + size_t length, + loff_t *ppos) +{ + struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)]; + unsigned char *buf; + int ret = 0, written = 0; + DECLARE_WAITQUEUE(wait, current); + + if (!ir) { + printk(KERN_ERR "%s: called with invalid irctl\n", __func__); + return -ENODEV; + } + + dev_dbg(ir->d.dev, LOGHEAD "read called\n", ir->d.name, ir->d.minor); + + buf = kzalloc(ir->chunk_size, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + if (mutex_lock_interruptible(&ir->irctl_lock)) { + ret = -ERESTARTSYS; + goto out_unlocked; + } + if (!ir->attached) { + ret = -ENODEV; + goto out_locked; + } + + if (length % ir->chunk_size) { + ret = -EINVAL; + goto out_locked; + } + + /* + * 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); + if (!ret) + written += ir->buf->chunk_size; + else + ret = -EFAULT; + } + } + + remove_wait_queue(&ir->buf->wait_poll, &wait); + set_current_state(TASK_RUNNING); + +out_locked: + mutex_unlock(&ir->irctl_lock); + +out_unlocked: + kfree(buf); + dev_dbg(ir->d.dev, LOGHEAD "read result = %s (%d)\n", + ir->d.name, ir->d.minor, ret ? "<fail>" : "<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 __user *buffer, + size_t length, loff_t *ppos) +{ + struct irctl *ir = irctls[iminor(file->f_dentry->d_inode)]; + + if (!ir) { + printk(KERN_ERR "%s: called with invalid irctl\n", __func__); + return -ENODEV; + } + + 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"); |