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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 // rc-ir-raw.c - handle IR pulse/space events
 //
 // Copyright (C) 2010 by Mauro Carvalho Chehab
 
 #include <linux/export.h>
 #include <linux/kthread.h>
 #include <linux/mutex.h>
 #include <linux/kmod.h>
 #include <linux/sched.h>
 #include "rc-core-priv.h"
 
 /* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */
 static LIST_HEAD(ir_raw_client_list);
 
 /* Used to handle IR raw handler extensions */
 DEFINE_MUTEX(ir_raw_handler_lock);
 static LIST_HEAD(ir_raw_handler_list);
 static atomic64_t available_protocols = ATOMIC64_INIT(0);
 
 static int ir_raw_event_thread(void *data)
 {
     struct ir_raw_event ev;
     struct ir_raw_handler *handler;
     struct ir_raw_event_ctrl *raw = data;
     struct rc_dev *dev = raw->dev;
 
     while (1) {
         mutex_lock(&ir_raw_handler_lock);
         while (kfifo_out(&raw->kfifo, &ev, 1)) {
             if (is_timing_event(ev)) {
                 if (ev.duration == 0)
                     dev_warn_once(&dev->dev, "nonsensical timing event of duration 0");
                 if (is_timing_event(raw->prev_ev) &&
                     !is_transition(&ev, &raw->prev_ev))
                     dev_warn_once(&dev->dev, "two consecutive events of type %s",
                               TO_STR(ev.pulse));
             }
             list_for_each_entry(handler, &ir_raw_handler_list, list)
                 if (dev->enabled_protocols &
                     handler->protocols || !handler->protocols)
                     handler->decode(dev, ev);
             lirc_raw_event(dev, ev);
             raw->prev_ev = ev;
         }
         mutex_unlock(&ir_raw_handler_lock);
 
         set_current_state(TASK_INTERRUPTIBLE);
 
         if (kthread_should_stop()) {
             __set_current_state(TASK_RUNNING);
             break;
         } else if (!kfifo_is_empty(&raw->kfifo))
             set_current_state(TASK_RUNNING);
 
         schedule();
     }
 
     return 0;
 }
 
 /**
  * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
  * @dev:    the struct rc_dev device descriptor
  * @ev:     the struct ir_raw_event descriptor of the pulse/space
  *
  * This routine (which may be called from an interrupt context) stores a
  * pulse/space duration for the raw ir decoding state machines. Pulses are
  * signalled as positive values and spaces as negative values. A zero value
  * will reset the decoding state machines.
  */
 int ir_raw_event_store(struct rc_dev *dev, struct ir_raw_event *ev)
 {
     if (!dev->raw)
         return -EINVAL;
 
     dev_dbg(&dev->dev, "sample: (%05dus %s)\n",
         ev->duration, TO_STR(ev->pulse));
 
     if (!kfifo_put(&dev->raw->kfifo, *ev)) {
         dev_err(&dev->dev, "IR event FIFO is full!\n");
         return -ENOSPC;
     }
 
     return 0;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store);
 
 /**
  * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
  * @dev:    the struct rc_dev device descriptor
  * @pulse:  true for pulse, false for space
  *
  * This routine (which may be called from an interrupt context) is used to
  * store the beginning of an ir pulse or space (or the start/end of ir
  * reception) for the raw ir decoding state machines. This is used by
  * hardware which does not provide durations directly but only interrupts
  * (or similar events) on state change.
  */
 int ir_raw_event_store_edge(struct rc_dev *dev, bool pulse)
 {
     ktime_t         now;
     struct ir_raw_event ev = {};
 
     if (!dev->raw)
         return -EINVAL;
 
     now = ktime_get();
     ev.duration = ktime_to_us(ktime_sub(now, dev->raw->last_event));
     ev.pulse = !pulse;
 
     return ir_raw_event_store_with_timeout(dev, &ev);
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);
 
 /*
  * ir_raw_event_store_with_timeout() - pass a pulse/space duration to the raw
  *                     ir decoders, schedule decoding and
  *                     timeout
  * @dev:    the struct rc_dev device descriptor
  * @ev:     the struct ir_raw_event descriptor of the pulse/space
  *
  * This routine (which may be called from an interrupt context) stores a
  * pulse/space duration for the raw ir decoding state machines, schedules
  * decoding and generates a timeout.
  */
 int ir_raw_event_store_with_timeout(struct rc_dev *dev, struct ir_raw_event *ev)
 {
     ktime_t     now;
     int     rc = 0;
 
     if (!dev->raw)
         return -EINVAL;
 
     now = ktime_get();
 
     spin_lock(&dev->raw->edge_spinlock);
     rc = ir_raw_event_store(dev, ev);
 
     dev->raw->last_event = now;
 
     /* timer could be set to timeout (125ms by default) */
     if (!timer_pending(&dev->raw->edge_handle) ||
         time_after(dev->raw->edge_handle.expires,
                jiffies + msecs_to_jiffies(15))) {
         mod_timer(&dev->raw->edge_handle,
               jiffies + msecs_to_jiffies(15));
     }
     spin_unlock(&dev->raw->edge_spinlock);
 
     return rc;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store_with_timeout);
 
 /**
  * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing
  * @dev:    the struct rc_dev device descriptor
  * @ev:     the event that has occurred
  *
  * This routine (which may be called from an interrupt context) works
  * in similar manner to ir_raw_event_store_edge.
  * This routine is intended for devices with limited internal buffer
  * It automerges samples of same type, and handles timeouts. Returns non-zero
  * if the event was added, and zero if the event was ignored due to idle
  * processing.
  */
 int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev)
 {
     if (!dev->raw)
         return -EINVAL;
 
     /* Ignore spaces in idle mode */
     if (dev->idle && !ev->pulse)
         return 0;
     else if (dev->idle)
         ir_raw_event_set_idle(dev, false);
 
     if (!dev->raw->this_ev.duration)
         dev->raw->this_ev = *ev;
     else if (ev->pulse == dev->raw->this_ev.pulse)
         dev->raw->this_ev.duration += ev->duration;
     else {
         ir_raw_event_store(dev, &dev->raw->this_ev);
         dev->raw->this_ev = *ev;
     }
 
     /* Enter idle mode if necessary */
     if (!ev->pulse && dev->timeout &&
         dev->raw->this_ev.duration >= dev->timeout)
         ir_raw_event_set_idle(dev, true);
 
     return 1;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter);
 
 /**
  * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not
  * @dev:    the struct rc_dev device descriptor
  * @idle:   whether the device is idle or not
  */
 void ir_raw_event_set_idle(struct rc_dev *dev, bool idle)
 {
     if (!dev->raw)
         return;
 
     dev_dbg(&dev->dev, "%s idle mode\n", idle ? "enter" : "leave");
 
     if (idle) {
         dev->raw->this_ev.timeout = true;
         ir_raw_event_store(dev, &dev->raw->this_ev);
         dev->raw->this_ev = (struct ir_raw_event) {};
     }
 
     if (dev->s_idle)
         dev->s_idle(dev, idle);
 
     dev->idle = idle;
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_set_idle);
 
 /**
  * ir_raw_event_handle() - schedules the decoding of stored ir data
  * @dev:    the struct rc_dev device descriptor
  *
  * This routine will tell rc-core to start decoding stored ir data.
  */
 void ir_raw_event_handle(struct rc_dev *dev)
 {
     if (!dev->raw || !dev->raw->thread)
         return;
 
     wake_up_process(dev->raw->thread);
 }
 EXPORT_SYMBOL_GPL(ir_raw_event_handle);
 
 /* used internally by the sysfs interface */
 u64
 ir_raw_get_allowed_protocols(void)
 {
     return atomic64_read(&available_protocols);
 }
 
 static int change_protocol(struct rc_dev *dev, u64 *rc_proto)
 {
     struct ir_raw_handler *handler;
     u32 timeout = 0;
 
     mutex_lock(&ir_raw_handler_lock);
     list_for_each_entry(handler, &ir_raw_handler_list, list) {
         if (!(dev->enabled_protocols & handler->protocols) &&
             (*rc_proto & handler->protocols) && handler->raw_register)
             handler->raw_register(dev);
 
         if ((dev->enabled_protocols & handler->protocols) &&
             !(*rc_proto & handler->protocols) &&
             handler->raw_unregister)
             handler->raw_unregister(dev);
     }
     mutex_unlock(&ir_raw_handler_lock);
 
     if (!dev->max_timeout)
         return 0;
 
     mutex_lock(&ir_raw_handler_lock);
     list_for_each_entry(handler, &ir_raw_handler_list, list) {
         if (handler->protocols & *rc_proto) {
             if (timeout < handler->min_timeout)
                 timeout = handler->min_timeout;
         }
     }
     mutex_unlock(&ir_raw_handler_lock);
 
     if (timeout == 0)
         timeout = IR_DEFAULT_TIMEOUT;
     else
         timeout += MS_TO_US(10);
 
     if (timeout < dev->min_timeout)
         timeout = dev->min_timeout;
     else if (timeout > dev->max_timeout)
         timeout = dev->max_timeout;
 
     if (dev->s_timeout)
         dev->s_timeout(dev, timeout);
     else
         dev->timeout = timeout;
 
     return 0;
 }
 
 static void ir_raw_disable_protocols(struct rc_dev *dev, u64 protocols)
 {
     mutex_lock(&dev->lock);
     dev->enabled_protocols &= ~protocols;
     mutex_unlock(&dev->lock);
 }
 
 /**
  * ir_raw_gen_manchester() - Encode data with Manchester (bi-phase) modulation.
  * @ev:     Pointer to pointer to next free event. *@ev is incremented for
  *      each raw event filled.
  * @max:    Maximum number of raw events to fill.
  * @timings:    Manchester modulation timings.
  * @n:      Number of bits of data.
  * @data:   Data bits to encode.
  *
  * Encodes the @n least significant bits of @data using Manchester (bi-phase)
  * modulation with the timing characteristics described by @timings, writing up
  * to @max raw IR events using the *@ev pointer.
  *
  * Returns: 0 on success.
  *      -ENOBUFS if there isn't enough space in the array to fit the
  *      full encoded data. In this case all @max events will have been
  *      written.
  */
 int ir_raw_gen_manchester(struct ir_raw_event **ev, unsigned int max,
               const struct ir_raw_timings_manchester *timings,
               unsigned int n, u64 data)
 {
     bool need_pulse;
     u64 i;
     int ret = -ENOBUFS;
 
     i = BIT_ULL(n - 1);
 
     if (timings->leader_pulse) {
         if (!max--)
             return ret;
         init_ir_raw_event_duration((*ev), 1, timings->leader_pulse);
         if (timings->leader_space) {
             if (!max--)
                 return ret;
             init_ir_raw_event_duration(++(*ev), 0,
                            timings->leader_space);
         }
     } else {
         /* continue existing signal */
         --(*ev);
     }
     /* from here on *ev will point to the last event rather than the next */
 
     while (n && i > 0) {
         need_pulse = !(data & i);
         if (timings->invert)
             need_pulse = !need_pulse;
         if (need_pulse == !!(*ev)->pulse) {
             (*ev)->duration += timings->clock;
         } else {
             if (!max--)
                 goto nobufs;
             init_ir_raw_event_duration(++(*ev), need_pulse,
                            timings->clock);
         }
 
         if (!max--)
             goto nobufs;
         init_ir_raw_event_duration(++(*ev), !need_pulse,
                        timings->clock);
         i >>= 1;
     }
 
     if (timings->trailer_space) {
         if (!(*ev)->pulse)
             (*ev)->duration += timings->trailer_space;
         else if (!max--)
             goto nobufs;
         else
             init_ir_raw_event_duration(++(*ev), 0,
                            timings->trailer_space);
     }
 
     ret = 0;
 nobufs:
     /* point to the next event rather than last event before returning */
     ++(*ev);
     return ret;
 }
 EXPORT_SYMBOL(ir_raw_gen_manchester);
 
 /**
  * ir_raw_gen_pd() - Encode data to raw events with pulse-distance modulation.
  * @ev:     Pointer to pointer to next free event. *@ev is incremented for
  *      each raw event filled.
  * @max:    Maximum number of raw events to fill.
  * @timings:    Pulse distance modulation timings.
  * @n:      Number of bits of data.
  * @data:   Data bits to encode.
  *
  * Encodes the @n least significant bits of @data using pulse-distance
  * modulation with the timing characteristics described by @timings, writing up
  * to @max raw IR events using the *@ev pointer.
  *
  * Returns: 0 on success.
  *      -ENOBUFS if there isn't enough space in the array to fit the
  *      full encoded data. In this case all @max events will have been
  *      written.
  */
 int ir_raw_gen_pd(struct ir_raw_event **ev, unsigned int max,
           const struct ir_raw_timings_pd *timings,
           unsigned int n, u64 data)
 {
     int i;
     int ret;
     unsigned int space;
 
     if (timings->header_pulse) {
         ret = ir_raw_gen_pulse_space(ev, &max, timings->header_pulse,
                          timings->header_space);
         if (ret)
             return ret;
     }
 
     if (timings->msb_first) {
         for (i = n - 1; i >= 0; --i) {
             space = timings->bit_space[(data >> i) & 1];
             ret = ir_raw_gen_pulse_space(ev, &max,
                              timings->bit_pulse,
                              space);
             if (ret)
                 return ret;
         }
     } else {
         for (i = 0; i < n; ++i, data >>= 1) {
             space = timings->bit_space[data & 1];
             ret = ir_raw_gen_pulse_space(ev, &max,
                              timings->bit_pulse,
                              space);
             if (ret)
                 return ret;
         }
     }
 
     ret = ir_raw_gen_pulse_space(ev, &max, timings->trailer_pulse,
                      timings->trailer_space);
     return ret;
 }
 EXPORT_SYMBOL(ir_raw_gen_pd);
 
 /**
  * ir_raw_gen_pl() - Encode data to raw events with pulse-length modulation.
  * @ev:     Pointer to pointer to next free event. *@ev is incremented for
  *      each raw event filled.
  * @max:    Maximum number of raw events to fill.
  * @timings:    Pulse distance modulation timings.
  * @n:      Number of bits of data.
  * @data:   Data bits to encode.
  *
  * Encodes the @n least significant bits of @data using space-distance
  * modulation with the timing characteristics described by @timings, writing up
  * to @max raw IR events using the *@ev pointer.
  *
  * Returns: 0 on success.
  *      -ENOBUFS if there isn't enough space in the array to fit the
  *      full encoded data. In this case all @max events will have been
  *      written.
  */
 int ir_raw_gen_pl(struct ir_raw_event **ev, unsigned int max,
           const struct ir_raw_timings_pl *timings,
           unsigned int n, u64 data)
 {
     int i;
     int ret = -ENOBUFS;
     unsigned int pulse;
 
     if (!max--)
         return ret;
 
     init_ir_raw_event_duration((*ev)++, 1, timings->header_pulse);
 
     if (timings->msb_first) {
         for (i = n - 1; i >= 0; --i) {
             if (!max--)
                 return ret;
             init_ir_raw_event_duration((*ev)++, 0,
                            timings->bit_space);
             if (!max--)
                 return ret;
             pulse = timings->bit_pulse[(data >> i) & 1];
             init_ir_raw_event_duration((*ev)++, 1, pulse);
         }
     } else {
         for (i = 0; i < n; ++i, data >>= 1) {
             if (!max--)
                 return ret;
             init_ir_raw_event_duration((*ev)++, 0,
                            timings->bit_space);
             if (!max--)
                 return ret;
             pulse = timings->bit_pulse[data & 1];
             init_ir_raw_event_duration((*ev)++, 1, pulse);
         }
     }
 
     if (!max--)
         return ret;
 
     init_ir_raw_event_duration((*ev)++, 0, timings->trailer_space);
 
     return 0;
 }
 EXPORT_SYMBOL(ir_raw_gen_pl);
 
 /**
  * ir_raw_encode_scancode() - Encode a scancode as raw events
  *
  * @protocol:       protocol
  * @scancode:       scancode filter describing a single scancode
  * @events:     array of raw events to write into
  * @max:        max number of raw events
  *
  * Attempts to encode the scancode as raw events.
  *
  * Returns: The number of events written.
  *      -ENOBUFS if there isn't enough space in the array to fit the
  *      encoding. In this case all @max events will have been written.
  *      -EINVAL if the scancode is ambiguous or invalid, or if no
  *      compatible encoder was found.
  */
 int ir_raw_encode_scancode(enum rc_proto protocol, u32 scancode,
                struct ir_raw_event *events, unsigned int max)
 {
     struct ir_raw_handler *handler;
     int ret = -EINVAL;
     u64 mask = 1ULL << protocol;
 
     ir_raw_load_modules(&mask);
 
     mutex_lock(&ir_raw_handler_lock);
     list_for_each_entry(handler, &ir_raw_handler_list, list) {
         if (handler->protocols & mask && handler->encode) {
             ret = handler->encode(protocol, scancode, events, max);
             if (ret >= 0 || ret == -ENOBUFS)
                 break;
         }
     }
     mutex_unlock(&ir_raw_handler_lock);
 
     return ret;
 }
 EXPORT_SYMBOL(ir_raw_encode_scancode);
 
 /**
  * ir_raw_edge_handle() - Handle ir_raw_event_store_edge() processing
  *
  * @t:      timer_list
  *
  * This callback is armed by ir_raw_event_store_edge(). It does two things:
  * first of all, rather than calling ir_raw_event_handle() for each
  * edge and waking up the rc thread, 15 ms after the first edge
  * ir_raw_event_handle() is called. Secondly, generate a timeout event
  * no more IR is received after the rc_dev timeout.
  */
 static void ir_raw_edge_handle(struct timer_list *t)
 {
     struct ir_raw_event_ctrl *raw = from_timer(raw, t, edge_handle);
     struct rc_dev *dev = raw->dev;
     unsigned long flags;
     ktime_t interval;
 
     spin_lock_irqsave(&dev->raw->edge_spinlock, flags);
     interval = ktime_sub(ktime_get(), dev->raw->last_event);
     if (ktime_to_us(interval) >= dev->timeout) {
         struct ir_raw_event ev = {
             .timeout = true,
             .duration = ktime_to_us(interval)
         };
 
         ir_raw_event_store(dev, &ev);
     } else {
         mod_timer(&dev->raw->edge_handle,
               jiffies + usecs_to_jiffies(dev->timeout -
                              ktime_to_us(interval)));
     }
     spin_unlock_irqrestore(&dev->raw->edge_spinlock, flags);
 
     ir_raw_event_handle(dev);
 }
 
 /**
  * ir_raw_encode_carrier() - Get carrier used for protocol
  *
  * @protocol:       protocol
  *
  * Attempts to find the carrier for the specified protocol
  *
  * Returns: The carrier in Hz
  *      -EINVAL if the protocol is invalid, or if no
  *      compatible encoder was found.
  */
 int ir_raw_encode_carrier(enum rc_proto protocol)
 {
     struct ir_raw_handler *handler;
     int ret = -EINVAL;
     u64 mask = BIT_ULL(protocol);
 
     mutex_lock(&ir_raw_handler_lock);
     list_for_each_entry(handler, &ir_raw_handler_list, list) {
         if (handler->protocols & mask && handler->encode) {
             ret = handler->carrier;
             break;
         }
     }
     mutex_unlock(&ir_raw_handler_lock);
 
     return ret;
 }
 EXPORT_SYMBOL(ir_raw_encode_carrier);
 
 /*
  * Used to (un)register raw event clients
  */
 int ir_raw_event_prepare(struct rc_dev *dev)
 {
     if (!dev)
         return -EINVAL;
 
     dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL);
     if (!dev->raw)
         return -ENOMEM;
 
     dev->raw->dev = dev;
     dev->change_protocol = change_protocol;
     dev->idle = true;
     spin_lock_init(&dev->raw->edge_spinlock);
     timer_setup(&dev->raw->edge_handle, ir_raw_edge_handle, 0);
     INIT_KFIFO(dev->raw->kfifo);
 
     return 0;
 }
 
 int ir_raw_event_register(struct rc_dev *dev)
 {
     struct task_struct *thread;
 
     thread = kthread_run(ir_raw_event_thread, dev->raw, "rc%u", dev->minor);
     if (IS_ERR(thread))
         return PTR_ERR(thread);
 
     dev->raw->thread = thread;
 
     mutex_lock(&ir_raw_handler_lock);
     list_add_tail(&dev->raw->list, &ir_raw_client_list);
     mutex_unlock(&ir_raw_handler_lock);
 
     return 0;
 }
 
 void ir_raw_event_free(struct rc_dev *dev)
 {
     if (!dev)
         return;
 
     kfree(dev->raw);
     dev->raw = NULL;
 }
 
 void ir_raw_event_unregister(struct rc_dev *dev)
 {
     struct ir_raw_handler *handler;
 
     if (!dev || !dev->raw)
         return;
 
     kthread_stop(dev->raw->thread);
     del_timer_sync(&dev->raw->edge_handle);
 
     mutex_lock(&ir_raw_handler_lock);
     list_del(&dev->raw->list);
     list_for_each_entry(handler, &ir_raw_handler_list, list)
         if (handler->raw_unregister &&
             (handler->protocols & dev->enabled_protocols))
             handler->raw_unregister(dev);
 
     lirc_bpf_free(dev);
 
     ir_raw_event_free(dev);
 
     /*
      * A user can be calling bpf(BPF_PROG_{QUERY|ATTACH|DETACH}), so
      * ensure that the raw member is null on unlock; this is how
      * "device gone" is checked.
      */
     mutex_unlock(&ir_raw_handler_lock);
 }
 
 /*
  * Extension interface - used to register the IR decoders
  */
 
 int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
 {
     mutex_lock(&ir_raw_handler_lock);
     list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
     atomic64_or(ir_raw_handler->protocols, &available_protocols);
     mutex_unlock(&ir_raw_handler_lock);
 
     return 0;
 }
 EXPORT_SYMBOL(ir_raw_handler_register);
 
 void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
 {
     struct ir_raw_event_ctrl *raw;
     u64 protocols = ir_raw_handler->protocols;
 
     mutex_lock(&ir_raw_handler_lock);
     list_del(&ir_raw_handler->list);
     list_for_each_entry(raw, &ir_raw_client_list, list) {
         if (ir_raw_handler->raw_unregister &&
             (raw->dev->enabled_protocols & protocols))
             ir_raw_handler->raw_unregister(raw->dev);
         ir_raw_disable_protocols(raw->dev, protocols);
     }
     atomic64_andnot(protocols, &available_protocols);
     mutex_unlock(&ir_raw_handler_lock);
 }
 EXPORT_SYMBOL(ir_raw_handler_unregister);

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