[media] IR: plug races in IR raw thread

#define _IR_RAW_EVENT

#include <linux/slab.h>

#include <linux/spinlock.h>

#include <media/ir-core.h>

struct ir_raw_handler {

struct ir_raw_event_ctrl {

	struct list_head		list;		/* to keep track of raw clients */

	struct task_struct		*thread;

	spinlock_t			lock;

	struct kfifo			kfifo;		/* fifo for the pulse/space durations */

	ktime_t				last_event;	/* when last event occurred */

	enum raw_event_type		last_type;	/* last event type */

	struct ir_raw_event ev;

	struct ir_raw_handler *handler;

	struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data;

	int retval;

	while (!kthread_should_stop()) {

		try_to_freeze();

		mutex_lock(&ir_raw_handler_lock);

		spin_lock_irq(&raw->lock);

		retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev));

		if (!retval) {

			set_current_state(TASK_INTERRUPTIBLE);

			if (kthread_should_stop())

				set_current_state(TASK_RUNNING);

			spin_unlock_irq(&raw->lock);

			schedule();

			continue;

		}

		spin_unlock_irq(&raw->lock);

		while (kfifo_out(&raw->kfifo, &ev, sizeof(ev)) == sizeof(ev)) {

		BUG_ON(retval != sizeof(ev));

		mutex_lock(&ir_raw_handler_lock);

		list_for_each_entry(handler, &ir_raw_handler_list, list)

			handler->decode(raw->input_dev, ev);

		raw->prev_ev = ev;

		}

		mutex_unlock(&ir_raw_handler_lock);

		set_current_state(TASK_INTERRUPTIBLE);

		schedule();

	}

	return 0;

void ir_raw_event_handle(struct input_dev *input_dev)

{

	struct ir_input_dev *ir = input_get_drvdata(input_dev);

	unsigned long flags;

	if (!ir->raw)

		return;

	spin_lock_irqsave(&ir->raw->lock, flags);

	wake_up_process(ir->raw->thread);

	spin_unlock_irqrestore(&ir->raw->lock, flags);

}

EXPORT_SYMBOL_GPL(ir_raw_event_handle);

		return rc;

	}

	spin_lock_init(&ir->raw->lock);

	ir->raw->thread = kthread_run(ir_raw_event_thread, ir->raw,

			"rc%u",  (unsigned int)ir->devno);