/*
* 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.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/file.h>
#include <linux/idr.h>
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include "rc-core-priv.h"
#include <uapi/linux/lirc.h>
#define LIRCBUF_SIZE 256
static dev_t lirc_base_dev;
/* Used to keep track of allocated lirc devices */
static DEFINE_IDA(lirc_ida);
/* Only used for sysfs but defined to void otherwise */
static struct class *lirc_class;
/**
* ir_lirc_raw_event() - Send raw IR data to lirc to be relayed to userspace
*
* @dev: the struct rc_dev descriptor of the device
* @ev: the struct ir_raw_event descriptor of the pulse/space
*/
void ir_lirc_raw_event(struct rc_dev *dev, struct ir_raw_event ev)
{
unsigned long flags;
struct lirc_fh *fh;
int sample;
/* Packet start */
if (ev.reset) {
/*
* Userspace expects a long space event before the start of
* the signal to use as a sync. This may be done with repeat
* packets and normal samples. But if a reset has been sent
* then we assume that a long time has passed, so we send a
* space with the maximum time value.
*/
sample = LIRC_SPACE(LIRC_VALUE_MASK);
dev_dbg(&dev->dev, "delivering reset sync space to lirc_dev\n");
/* Carrier reports */
} else if (ev.carrier_report) {
sample = LIRC_FREQUENCY(ev.carrier);
dev_dbg(&dev->dev, "carrier report (freq: %d)\n", sample);
/* Packet end */
} else if (ev.timeout) {
if (dev->gap)
return;
dev->gap_start = ktime_get();
dev->gap = true;
dev->gap_duration = ev.duration;
sample = LIRC_TIMEOUT(ev.duration / 1000);
dev_dbg(&dev->dev, "timeout report (duration: %d)\n", sample);
/* Normal sample */
} else {
if (dev->gap) {
dev->gap_duration += ktime_to_ns(ktime_sub(ktime_get(),
dev->gap_start));
/* Convert to ms and cap by LIRC_VALUE_MASK */
do_div(dev->gap_duration, 1000);
dev->gap_duration = min_t(u64, dev->gap_duration,
LIRC_VALUE_MASK);
spin_lock_irqsave(&dev->lirc_fh_lock, flags);
list_for_each_entry(fh, &dev->lirc_fh, list)
kfifo_put(&fh->rawir,
LIRC_SPACE(dev->gap_duration));
spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
dev->gap = false;
}
sample = ev.pulse ? LIRC_PULSE(ev.duration / 1000) :
LIRC_SPACE(ev.duration / 1000);
dev_dbg(&dev->dev, "delivering %uus %s to lirc_dev\n",
TO_US(ev.duration), TO_STR(ev.pulse));
}
/*
* bpf does not care about the gap generated above; that exists
* for backwards compatibility
*/
lirc_bpf_run(dev, sample);
spin_lock_irqsave(&dev->lirc_fh_lock, flags);
list_for_each_entry(fh, &dev->lirc_fh, list) {
if (LIRC_IS_TIMEOUT(sample) && !fh->send_timeout_reports)
continue;
if (kfifo_put(&fh->rawir, sample))
wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM);
}
spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
}
/**
* ir_lirc_scancode_event() - Send scancode data to lirc to be relayed to
* userspace. This can be called in atomic context.
* @dev: the struct rc_dev descriptor of the device
* @lsc: the struct lirc_scancode describing the decoded scancode
*/
void ir_lirc_scancode_event(struct rc_dev *dev, struct lirc_scancode *lsc)
{
unsigned long flags;
struct lirc_fh *fh;
lsc->timestamp = ktime_get_ns();
spin_lock_irqsave(&dev->lirc_fh_lock, flags);
list_for_each_entry(fh, &dev->lirc_fh, list) {
if (kfifo_put(&fh->scancodes, *lsc))
wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM);
}
spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
}
EXPORT_SYMBOL_GPL(ir_lirc_scancode_event);
static int ir_lirc_open(struct inode *inode, struct file *file)
{
struct rc_dev *dev = container_of(inode->i_cdev, struct rc_dev,
lirc_cdev);
struct lirc_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
unsigned long flags;
int retval;
if (!fh)
return -ENOMEM;
get_device(&dev->dev);
if (!dev->registered) {
retval = -ENODEV;
goto out_fh;
}
if (dev->driver_type == RC_DRIVER_IR_RAW) {
if (kfifo_alloc(&fh->rawir, MAX_IR_EVENT_SIZE, GFP_KERNEL)) {
retval = -ENOMEM;
goto out_fh;
}
}
if (dev->driver_type != RC_DRIVER_IR_RAW_TX) {
if (kfifo_alloc(&fh->scancodes, 32, GFP_KERNEL)) {
retval = -ENOMEM;
goto out_rawir;
}
}
fh->send_mode = LIRC_MODE_PULSE;
fh->rc = dev;
fh->send_timeout_reports = true;
if (dev->driver_type == RC_DRIVER_SCANCODE)
fh->rec_mode = LIRC_MODE_SCANCODE;
else
fh->rec_mode = LIRC_MODE_MODE2;
retval = rc_open(dev);
if (retval)
goto out_kfifo;
init_waitqueue_head(&fh->wait_poll);
file->private_data = fh;
spin_lock_irqsave(&dev->lirc_fh_lock, flags);
list_add(&fh->list, &dev->lirc_fh);
spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
nonseekable_open(inode, file);
return 0;
out_kfifo:
if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
kfifo_free(&fh->scancodes);
out_rawir:
if (dev->driver_type == RC_DRIVER_IR_RAW)
kfifo_free(&fh->rawir);
out_fh:
kfree(fh);
put_device(&dev->dev);
return retval;
}
static int ir_lirc_close(struct inode *inode, struct file *file)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *dev = fh->rc;
unsigned long flags;
spin_lock_irqsave(&dev->lirc_fh_lock, flags);
list_del(&fh->list);
spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
if (dev->driver_type == RC_DRIVER_IR_RAW)
kfifo_free(&fh->rawir);
if (dev->driver_type != RC_DRIVER_IR_RAW_TX)
kfifo_free(&fh->scancodes);
kfree(fh);
rc_close(dev);
put_device(&dev->dev);
return 0;
}
static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
size_t n, loff_t *ppos)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *dev = fh->rc;
unsigned int *txbuf;
struct ir_raw_event *raw = NULL;
ssize_t ret;
size_t count;
ktime_t start;
s64 towait;
unsigned int duration = 0; /* signal duration in us */
int i;
ret = mutex_lock_interruptible(&dev->lock);
if (ret)
return ret;
if (!dev->registered) {
ret = -ENODEV;
goto out_unlock;
}
if (!dev->tx_ir) {
ret = -EINVAL;
goto out_unlock;
}
if (fh->send_mode == LIRC_MODE_SCANCODE) {
struct lirc_scancode scan;
if (n != sizeof(scan)) {
ret = -EINVAL;
goto out_unlock;
}
if (copy_from_user(&scan, buf, sizeof(scan))) {
ret = -EFAULT;
goto out_unlock;
}
if (scan.flags || scan.keycode || scan.timestamp) {
ret = -EINVAL;
goto out_unlock;
}
/*
* The scancode field in lirc_scancode is 64-bit simply
* to future-proof it, since there are IR protocols encode
* use more than 32 bits. For now only 32-bit protocols
* are supported.
*/
if (scan.scancode > U32_MAX ||
!rc_validate_scancode(scan.rc_proto, scan.scancode)) {
ret = -EINVAL;
goto out_unlock;
}
raw = kmalloc_array(LIRCBUF_SIZE, sizeof(*raw), GFP_KERNEL);
if (!raw) {
ret = -ENOMEM;
goto out_unlock;
}
ret = ir_raw_encode_scancode(scan.rc_proto, scan.scancode,
raw, LIRCBUF_SIZE);
if (ret < 0)
goto out_kfree_raw;
count = ret;
txbuf = kmalloc_array(count, sizeof(unsigned int), GFP_KERNEL);
if (!txbuf) {
ret = -ENOMEM;
goto out_kfree_raw;
}
for (i = 0; i < count; i++)
/* Convert from NS to US */
txbuf[i] = DIV_ROUND_UP(raw[i].duration, 1000);
if (dev->s_tx_carrier) {
int carrier = ir_raw_encode_carrier(scan.rc_proto);
if (carrier > 0)
dev->s_tx_carrier(dev, carrier);
}
} else {
if (n < sizeof(unsigned int) || n % sizeof(unsigned int)) {
ret = -EINVAL;
goto out_unlock;
}
count = n / sizeof(unsigned int);
if (count > LIRCBUF_SIZE || count % 2 == 0) {
ret = -EINVAL;
goto out_unlock;
}
txbuf = memdup_user(buf, n);
if (IS_ERR(txbuf)) {
ret = PTR_ERR(txbuf);
goto out_unlock;
}
}
for (i = 0; i < count; i++) {
if (txbuf[i] > IR_MAX_DURATION / 1000 - duration || !txbuf[i]) {
ret = -EINVAL;
goto out_kfree;
}
duration += txbuf[i];
}
start = ktime_get();
ret = dev->tx_ir(dev, txbuf, count);
if (ret < 0)
goto out_kfree;
kfree(txbuf);
kfree(raw);
mutex_unlock(&dev->lock);
/*
* The lircd gap calculation expects the write function to
* wait for the actual IR signal to be transmitted before
* returning.
*/
towait = ktime_us_delta(ktime_add_us(start, duration),
ktime_get());
if (towait > 0) {
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(usecs_to_jiffies(towait));
}
return n;
out_kfree:
kfree(txbuf);
out_kfree_raw:
kfree(raw);
out_unlock:
mutex_unlock(&dev->lock);
return ret;
}
static long ir_lirc_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *dev = fh->rc;
u32 __user *argp = (u32 __user *)(arg);
u32 val = 0;
int ret;
if (_IOC_DIR(cmd) & _IOC_WRITE) {
ret = get_user(val, argp);
if (ret)
return ret;
}
ret = mutex_lock_interruptible(&dev->lock);
if (ret)
return ret;
if (!dev->registered) {
ret = -ENODEV;
goto out;
}
switch (cmd) {
case LIRC_GET_FEATURES:
if (dev->driver_type == RC_DRIVER_SCANCODE)
val |= LIRC_CAN_REC_SCANCODE;
if (dev->driver_type == RC_DRIVER_IR_RAW) {
val |= LIRC_CAN_REC_MODE2;
if (dev->rx_resolution)
val |= LIRC_CAN_GET_REC_RESOLUTION;
}
if (dev->tx_ir) {
val |= LIRC_CAN_SEND_PULSE;
if (dev->s_tx_mask)
val |= LIRC_CAN_SET_TRANSMITTER_MASK;
if (dev->s_tx_carrier)
val |= LIRC_CAN_SET_SEND_CARRIER;
if (dev->s_tx_duty_cycle)
val |= LIRC_CAN_SET_SEND_DUTY_CYCLE;
}
if (dev->s_rx_carrier_range)
val |= LIRC_CAN_SET_REC_CARRIER |
LIRC_CAN_SET_REC_CARRIER_RANGE;
if (dev->s_learning_mode)
val |= LIRC_CAN_USE_WIDEBAND_RECEIVER;
if (dev->s_carrier_report)
val |= LIRC_CAN_MEASURE_CARRIER;
if (dev->max_timeout)
val |= LIRC_CAN_SET_REC_TIMEOUT;
break;
/* mode support */
case LIRC_GET_REC_MODE:
if (dev->driver_type == RC_DRIVER_IR_RAW_TX)
ret = -ENOTTY;
else
val = fh->rec_mode;
break;
case LIRC_SET_REC_MODE:
switch (dev->driver_type) {
case RC_DRIVER_IR_RAW_TX:
ret = -ENOTTY;
break;
case RC_DRIVER_SCANCODE:
if (val != LIRC_MODE_SCANCODE)
ret = -EINVAL;
break;
case RC_DRIVER_IR_RAW:
if (!(val == LIRC_MODE_MODE2 ||
val == LIRC_MODE_SCANCODE))
ret = -EINVAL;
break;
}
if (!ret)
fh->rec_mode = val;
break;
case LIRC_GET_SEND_MODE:
if (!dev->tx_ir)
ret = -ENOTTY;
else
val = fh->send_mode;
break;
case LIRC_SET_SEND_MODE:
if (!dev->tx_ir)
ret = -ENOTTY;
else if (!(val == LIRC_MODE_PULSE || val == LIRC_MODE_SCANCODE))
ret = -EINVAL;
else
fh->send_mode = val;
break;
/* TX settings */
case LIRC_SET_TRANSMITTER_MASK:
if (!dev->s_tx_mask)
ret = -ENOTTY;
else
ret = dev->s_tx_mask(dev, val);
break;
case LIRC_SET_SEND_CARRIER:
if (!dev->s_tx_carrier)
ret = -ENOTTY;
else
ret = dev->s_tx_carrier(dev, val);
break;
case LIRC_SET_SEND_DUTY_CYCLE:
if (!dev->s_tx_duty_cycle)
ret = -ENOTTY;
else if (val <= 0 || val >= 100)
ret = -EINVAL;
else
ret = dev->s_tx_duty_cycle(dev, val);
break;
/* RX settings */
case LIRC_SET_REC_CARRIER:
if (!dev->s_rx_carrier_range)
ret = -ENOTTY;
else if (val <= 0)
ret = -EINVAL;
else
ret = dev->s_rx_carrier_range(dev, fh->carrier_low,
val);
break;
case LIRC_SET_REC_CARRIER_RANGE:
if (!dev->s_rx_carrier_range)
ret = -ENOTTY;
else if (val <= 0)
ret = -EINVAL;
else
fh->carrier_low = val;
break;
case LIRC_GET_REC_RESOLUTION:
if (!dev->rx_resolution)
ret = -ENOTTY;
else
val = dev->rx_resolution / 1000;
break;
case LIRC_SET_WIDEBAND_RECEIVER:
if (!dev->s_learning_mode)
ret = -ENOTTY;
else
ret = dev->s_learning_mode(dev, !!val);
break;
case LIRC_SET_MEASURE_CARRIER_MODE:
if (!dev->s_carrier_report)
ret = -ENOTTY;
else
ret = dev->s_carrier_report(dev, !!val);
break;
/* Generic timeout support */
case LIRC_GET_MIN_TIMEOUT:
if (!dev->max_timeout)
ret = -ENOTTY;
else
val = DIV_ROUND_UP(dev->min_timeout, 1000);
break;
case LIRC_GET_MAX_TIMEOUT:
if (!dev->max_timeout)
ret = -ENOTTY;
else
val = dev->max_timeout / 1000;
break;
case LIRC_SET_REC_TIMEOUT:
if (!dev->max_timeout) {
ret = -ENOTTY;
} else if (val > U32_MAX / 1000) {
/* Check for multiply overflow */
ret = -EINVAL;
} else {
u32 tmp = val * 1000;
if (tmp < dev->min_timeout || tmp > dev->max_timeout)
ret = -EINVAL;
else if (dev->s_timeout)
ret = dev->s_timeout(dev, tmp);
else
dev->timeout = tmp;
}
break;
case LIRC_SET_REC_TIMEOUT_REPORTS:
if (!dev->timeout)
ret = -ENOTTY;
else
fh->send_timeout_reports = !!val;
break;
default:
ret = -ENOTTY;
}
if (!ret && _IOC_DIR(cmd) & _IOC_READ)
ret = put_user(val, argp);
out:
mutex_unlock(&dev->lock);
return ret;
}
static __poll_t ir_lirc_poll(struct file *file, struct poll_table_struct *wait)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *rcdev = fh->rc;
__poll_t events = 0;
poll_wait(file, &fh->wait_poll, wait);
if (!rcdev->registered) {
events = EPOLLHUP | EPOLLERR;
} else if (rcdev->driver_type != RC_DRIVER_IR_RAW_TX) {
if (fh->rec_mode == LIRC_MODE_SCANCODE &&
!kfifo_is_empty(&fh->scancodes))
events = EPOLLIN | EPOLLRDNORM;
if (fh->rec_mode == LIRC_MODE_MODE2 &&
!kfifo_is_empty(&fh->rawir))
events = EPOLLIN | EPOLLRDNORM;
}
return events;
}
static ssize_t ir_lirc_read_mode2(struct file *file, char __user *buffer,
size_t length)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *rcdev = fh->rc;
unsigned int copied;
int ret;
if (length < sizeof(unsigned int) || length % sizeof(unsigned int))
return -EINVAL;
do {
if (kfifo_is_empty(&fh->rawir)) {
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
ret = wait_event_interruptible(fh->wait_poll,
!kfifo_is_empty(&fh->rawir) ||
!rcdev->registered);
if (ret)
return ret;
}
if (!rcdev->registered)
return -ENODEV;
ret = mutex_lock_interruptible(&rcdev->lock);
if (ret)
return ret;
ret = kfifo_to_user(&fh->rawir, buffer, length, &copied);
mutex_unlock(&rcdev->lock);
if (ret)
return ret;
} while (copied == 0);
return copied;
}
static ssize_t ir_lirc_read_scancode(struct file *file, char __user *buffer,
size_t length)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *rcdev = fh->rc;
unsigned int copied;
int ret;
if (length < sizeof(struct lirc_scancode) ||
length % sizeof(struct lirc_scancode))
return -EINVAL;
do {
if (kfifo_is_empty(&fh->scancodes)) {
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
ret = wait_event_interruptible(fh->wait_poll,
!kfifo_is_empty(&fh->scancodes) ||
!rcdev->registered);
if (ret)
return ret;
}
if (!rcdev->registered)
return -ENODEV;
ret = mutex_lock_interruptible(&rcdev->lock);
if (ret)
return ret;
ret = kfifo_to_user(&fh->scancodes, buffer, length, &copied);
mutex_unlock(&rcdev->lock);
if (ret)
return ret;
} while (copied == 0);
return copied;
}
static ssize_t ir_lirc_read(struct file *file, char __user *buffer,
size_t length, loff_t *ppos)
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *rcdev = fh->rc;
if (rcdev->driver_type == RC_DRIVER_IR_RAW_TX)
return -EINVAL;
if (!rcdev->registered)
return -ENODEV;
if (fh->rec_mode == LIRC_MODE_MODE2)
return ir_lirc_read_mode2(file, buffer, length);
else /* LIRC_MODE_SCANCODE */
return ir_lirc_read_scancode(file, buffer, length);
}
static const struct file_operations lirc_fops = {
.owner = THIS_MODULE,
.write = ir_lirc_transmit_ir,
.unlocked_ioctl = ir_lirc_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = ir_lirc_ioctl,
#endif
.read = ir_lirc_read,
.poll = ir_lirc_poll,
.open = ir_lirc_open,
.release = ir_lirc_close,
.llseek = no_llseek,
};
static void lirc_release_device(struct device *ld)
{
struct rc_dev *rcdev = container_of(ld, struct rc_dev, lirc_dev);
put_device(&rcdev->dev);
}
int ir_lirc_register(struct rc_dev *dev)
{
int err, minor;
minor = ida_simple_get(&lirc_ida, 0, RC_DEV_MAX, GFP_KERNEL);
if (minor < 0)
return minor;
device_initialize(&dev->lirc_dev);
dev->lirc_dev.class = lirc_class;
dev->lirc_dev.parent = &dev->dev;
dev->lirc_dev.release = lirc_release_device;
dev->lirc_dev.devt = MKDEV(MAJOR(lirc_base_dev), minor);
dev_set_name(&dev->lirc_dev, "lirc%d", minor);
INIT_LIST_HEAD(&dev->lirc_fh);
spin_lock_init(&dev->lirc_fh_lock);
cdev_init(&dev->lirc_cdev, &lirc_fops);
err = cdev_device_add(&dev->lirc_cdev, &dev->lirc_dev);
if (err)
goto out_ida;
get_device(&dev->dev);
dev_info(&dev->dev, "lirc_dev: driver %s registered at minor = %d",
dev->driver_name, minor);
return 0;
out_ida:
ida_simple_remove(&lirc_ida, minor);
return err;
}
void ir_lirc_unregister(struct rc_dev *dev)
{
unsigned long flags;
struct lirc_fh *fh;
dev_dbg(&dev->dev, "lirc_dev: driver %s unregistered from minor = %d\n",
dev->driver_name, MINOR(dev->lirc_dev.devt));
spin_lock_irqsave(&dev->lirc_fh_lock, flags);
list_for_each_entry(fh, &dev->lirc_fh, list)
wake_up_poll(&fh->wait_poll, EPOLLHUP | EPOLLERR);
spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);
cdev_device_del(&dev->lirc_cdev, &dev->lirc_dev);
ida_simple_remove(&lirc_ida, MINOR(dev->lirc_dev.devt));
}
int __init lirc_dev_init(void)
{
int retval;
lirc_class = class_create(THIS_MODULE, "lirc");
if (IS_ERR(lirc_class)) {
pr_err("class_create failed\n");
return PTR_ERR(lirc_class);
}
retval = alloc_chrdev_region(&lirc_base_dev, 0, RC_DEV_MAX,
"BaseRemoteCtl");
if (retval) {
class_destroy(lirc_class);
pr_err("alloc_chrdev_region failed\n");
return retval;
}
pr_debug("IR Remote Control driver registered, major %d\n",
MAJOR(lirc_base_dev));
return 0;
}
void __exit lirc_dev_exit(void)
{
class_destroy(lirc_class);
unregister_chrdev_region(lirc_base_dev, RC_DEV_MAX);
}
struct rc_dev *rc_dev_get_from_fd(int fd)
{
struct fd f = fdget(fd);
struct lirc_fh *fh;
struct rc_dev *dev;
if (!f.file)
return ERR_PTR(-EBADF);
if (f.file->f_op != &lirc_fops) {
fdput(f);
return ERR_PTR(-EINVAL);
}
fh = f.file->private_data;
dev = fh->rc;
get_device(&dev->dev);
fdput(f);
return dev;
}
MODULE_ALIAS("lirc_dev");
