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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#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 1024
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 const struct class lirc_class = { .name = "lirc",};
/** * 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 lirc_raw_event(struct rc_dev *dev, struct ir_raw_event ev){ unsigned long flags; struct lirc_fh *fh; int sample;
/* Receiver overflow, data missing */ if (ev.overflow) { /* * Send lirc overflow message. This message is unknown to * lircd, but it will interpret this as a long space as * long as the value is set to high value. This resets its * decoder state. */ sample = LIRC_OVERFLOW(LIRC_VALUE_MASK); dev_dbg(&dev->dev, "delivering overflow 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) { dev->gap_start = ktime_get();
sample = LIRC_TIMEOUT(ev.duration); dev_dbg(&dev->dev, "timeout report (duration: %d)\n", sample);
/* Normal sample */ } else { if (dev->gap_start) { u64 duration = ktime_us_delta(ktime_get(), dev->gap_start);
/* Cap by LIRC_VALUE_MASK */ duration = min_t(u64, 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(duration)); spin_unlock_irqrestore(&dev->lirc_fh_lock, flags); dev->gap_start = 0; }
sample = ev.pulse ? LIRC_PULSE(ev.duration) : LIRC_SPACE(ev.duration); dev_dbg(&dev->dev, "delivering %uus %s to lirc_dev\n", 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 (kfifo_put(&fh->rawir, sample)) wake_up_poll(&fh->wait_poll, EPOLLIN | EPOLLRDNORM); } spin_unlock_irqrestore(&dev->lirc_fh_lock, flags);}
/** * 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 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(lirc_scancode_event);
static int 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_obj(*fh); 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;
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);
stream_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 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 lirc_transmit(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 || scan.rc_proto > RC_PROTO_MAX) { ret = -EINVAL; goto out_unlock; }
/* We only have encoders for 32-bit protocols. */ if (scan.scancode > U32_MAX || !rc_validate_scancode(scan.rc_proto, scan.scancode)) { ret = -EINVAL; goto out_unlock; }
raw = kmalloc_objs(*raw, LIRCBUF_SIZE); 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;
/* drop trailing space */ if (!(ret % 2)) count = ret - 1; else 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++) txbuf[i] = raw[i].duration;
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 - 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 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_wideband_receiver) 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; break;
case LIRC_SET_WIDEBAND_RECEIVER: if (!dev->s_wideband_receiver) ret = -ENOTTY; else ret = dev->s_wideband_receiver(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 = dev->min_timeout; break;
case LIRC_GET_MAX_TIMEOUT: if (!dev->max_timeout) ret = -ENOTTY; else val = dev->max_timeout; break;
case LIRC_SET_REC_TIMEOUT: if (!dev->max_timeout) { ret = -ENOTTY; } else { if (val < dev->min_timeout || val > dev->max_timeout) ret = -EINVAL; else if (dev->s_timeout) ret = dev->s_timeout(dev, val); else dev->timeout = val; } break;
case LIRC_GET_REC_TIMEOUT: if (!dev->timeout) ret = -ENOTTY; else val = dev->timeout; break;
case LIRC_SET_REC_TIMEOUT_REPORTS: if (dev->driver_type != RC_DRIVER_IR_RAW) ret = -ENOTTY; 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 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 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 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 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 lirc_read_mode2(file, buffer, length); else /* LIRC_MODE_SCANCODE */ return lirc_read_scancode(file, buffer, length);}
static const struct file_operations lirc_fops = { .owner = THIS_MODULE, .write = lirc_transmit, .unlocked_ioctl = lirc_ioctl, .compat_ioctl = compat_ptr_ioctl, .read = lirc_read, .poll = lirc_poll, .open = lirc_open, .release = lirc_close,};
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 lirc_register(struct rc_dev *dev){ const char *rx_type, *tx_type; int err, minor;
minor = ida_alloc_max(&lirc_ida, RC_DEV_MAX - 1, 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);
get_device(&dev->dev);
err = cdev_device_add(&dev->lirc_cdev, &dev->lirc_dev); if (err) goto out_put_device;
switch (dev->driver_type) { case RC_DRIVER_SCANCODE: rx_type = "scancode"; break; case RC_DRIVER_IR_RAW: rx_type = "raw IR"; break; default: rx_type = "no"; break; }
if (dev->tx_ir) tx_type = "raw IR"; else tx_type = "no";
dev_info(&dev->dev, "lirc_dev: driver %s registered at minor = %d, %s receiver, %s transmitter", dev->driver_name, minor, rx_type, tx_type);
return 0;
out_put_device: put_device(&dev->lirc_dev); ida_free(&lirc_ida, minor); return err;}
void 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_free(&lirc_ida, MINOR(dev->lirc_dev.devt));}
int __init lirc_dev_init(void){ int retval;
retval = class_register(&lirc_class); if (retval) return retval;
retval = alloc_chrdev_region(&lirc_base_dev, 0, RC_DEV_MAX, "lirc"); if (retval) { class_unregister(&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_unregister(&lirc_class); unregister_chrdev_region(lirc_base_dev, RC_DEV_MAX);}
struct rc_dev *rc_dev_get_from_fd(int fd, bool write){ CLASS(fd, f)(fd); struct lirc_fh *fh; struct rc_dev *dev;
if (fd_empty(f)) return ERR_PTR(-EBADF);
if (fd_file(f)->f_op != &lirc_fops) return ERR_PTR(-EINVAL);
if (write && !(fd_file(f)->f_mode & FMODE_WRITE)) return ERR_PTR(-EPERM);
fh = fd_file(f)->private_data; dev = fh->rc;
get_device(&dev->dev);
return dev;}
MODULE_ALIAS("lirc_dev");