diff options
Diffstat (limited to 'drivers/media/rc/ir-raw.c')
| -rw-r--r-- | drivers/media/rc/ir-raw.c | 371 | 
1 files changed, 371 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-raw.c b/drivers/media/rc/ir-raw.c new file mode 100644 index 00000000000..185baddcbf1 --- /dev/null +++ b/drivers/media/rc/ir-raw.c @@ -0,0 +1,371 @@ +/* ir-raw.c - handle IR pulse/space events + * + * Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.com> + * + * 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 version 2 of the License. + * + *  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. + */ + +#include <linux/kthread.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/freezer.h> +#include "rc-core-priv.h" + +/* Define the max number of pulse/space transitions to buffer */ +#define MAX_IR_EVENT_SIZE      512 + +/* 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 */ +static DEFINE_MUTEX(ir_raw_handler_lock); +static LIST_HEAD(ir_raw_handler_list); +static u64 available_protocols; + +#ifdef MODULE +/* Used to load the decoders */ +static struct work_struct wq_load; +#endif + +static int ir_raw_event_thread(void *data) +{ +	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()) { + +		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); + + +		BUG_ON(retval != sizeof(ev)); + +		mutex_lock(&ir_raw_handler_lock); +		list_for_each_entry(handler, &ir_raw_handler_list, list) +			handler->decode(raw->dev, ev); +		raw->prev_ev = ev; +		mutex_unlock(&ir_raw_handler_lock); +	} + +	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; + +	IR_dprintk(2, "sample: (%05dus %s)\n", +		   TO_US(ev->duration), TO_STR(ev->pulse)); + +	if (kfifo_in(&dev->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev)) +		return -ENOMEM; + +	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 + * @type:	the type of the event that has occurred + * + * 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, enum raw_event_type type) +{ +	ktime_t			now; +	s64			delta; /* ns */ +	struct ir_raw_event	ev; +	int			rc = 0; + +	if (!dev->raw) +		return -EINVAL; + +	now = ktime_get(); +	delta = ktime_to_ns(ktime_sub(now, dev->raw->last_event)); + +	/* Check for a long duration since last event or if we're +	 * being called for the first time, note that delta can't +	 * possibly be negative. +	 */ +	ev.duration = 0; +	if (delta > IR_MAX_DURATION || !dev->raw->last_type) +		type |= IR_START_EVENT; +	else +		ev.duration = delta; + +	if (type & IR_START_EVENT) +		ir_raw_event_reset(dev); +	else if (dev->raw->last_type & IR_SPACE) { +		ev.pulse = false; +		rc = ir_raw_event_store(dev, &ev); +	} else if (dev->raw->last_type & IR_PULSE) { +		ev.pulse = true; +		rc = ir_raw_event_store(dev, &ev); +	} else +		return 0; + +	dev->raw->last_event = now; +	dev->raw->last_type = type; +	return rc; +} +EXPORT_SYMBOL_GPL(ir_raw_event_store_edge); + +/** + * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing + * @dev:	the struct rc_dev device descriptor + * @type:	the type of the event that has occurred + * + * This routine (which may be called from an interrupt context) works + * in similiar 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 + */ +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 nessesary */ +	if (!ev->pulse && dev->timeout && +	    dev->raw->this_ev.duration >= dev->timeout) +		ir_raw_event_set_idle(dev, true); + +	return 0; +} +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; + +	IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave"); + +	if (idle) { +		dev->raw->this_ev.timeout = true; +		ir_raw_event_store(dev, &dev->raw->this_ev); +		init_ir_raw_event(&dev->raw->this_ev); +	} + +	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) +{ +	unsigned long flags; + +	if (!dev->raw) +		return; + +	spin_lock_irqsave(&dev->raw->lock, flags); +	wake_up_process(dev->raw->thread); +	spin_unlock_irqrestore(&dev->raw->lock, flags); +} +EXPORT_SYMBOL_GPL(ir_raw_event_handle); + +/* used internally by the sysfs interface */ +u64 +ir_raw_get_allowed_protocols() +{ +	u64 protocols; +	mutex_lock(&ir_raw_handler_lock); +	protocols = available_protocols; +	mutex_unlock(&ir_raw_handler_lock); +	return protocols; +} + +/* + * Used to (un)register raw event clients + */ +int ir_raw_event_register(struct rc_dev *dev) +{ +	int rc; +	struct ir_raw_handler *handler; + +	if (!dev) +		return -EINVAL; + +	dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL); +	if (!dev->raw) +		return -ENOMEM; + +	dev->raw->dev = dev; +	dev->raw->enabled_protocols = ~0; +	rc = kfifo_alloc(&dev->raw->kfifo, +			 sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE, +			 GFP_KERNEL); +	if (rc < 0) +		goto out; + +	spin_lock_init(&dev->raw->lock); +	dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw, +				       "rc%ld", dev->devno); + +	if (IS_ERR(dev->raw->thread)) { +		rc = PTR_ERR(dev->raw->thread); +		goto out; +	} + +	mutex_lock(&ir_raw_handler_lock); +	list_add_tail(&dev->raw->list, &ir_raw_client_list); +	list_for_each_entry(handler, &ir_raw_handler_list, list) +		if (handler->raw_register) +			handler->raw_register(dev); +	mutex_unlock(&ir_raw_handler_lock); + +	return 0; + +out: +	kfree(dev->raw); +	dev->raw = NULL; +	return rc; +} + +void ir_raw_event_unregister(struct rc_dev *dev) +{ +	struct ir_raw_handler *handler; + +	if (!dev || !dev->raw) +		return; + +	kthread_stop(dev->raw->thread); + +	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->raw_unregister(dev); +	mutex_unlock(&ir_raw_handler_lock); + +	kfifo_free(&dev->raw->kfifo); +	kfree(dev->raw); +	dev->raw = NULL; +} + +/* + * Extension interface - used to register the IR decoders + */ + +int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler) +{ +	struct ir_raw_event_ctrl *raw; + +	mutex_lock(&ir_raw_handler_lock); +	list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list); +	if (ir_raw_handler->raw_register) +		list_for_each_entry(raw, &ir_raw_client_list, list) +			ir_raw_handler->raw_register(raw->dev); +	available_protocols |= ir_raw_handler->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; + +	mutex_lock(&ir_raw_handler_lock); +	list_del(&ir_raw_handler->list); +	if (ir_raw_handler->raw_unregister) +		list_for_each_entry(raw, &ir_raw_client_list, list) +			ir_raw_handler->raw_unregister(raw->dev); +	available_protocols &= ~ir_raw_handler->protocols; +	mutex_unlock(&ir_raw_handler_lock); +} +EXPORT_SYMBOL(ir_raw_handler_unregister); + +#ifdef MODULE +static void init_decoders(struct work_struct *work) +{ +	/* Load the decoder modules */ + +	load_nec_decode(); +	load_rc5_decode(); +	load_rc6_decode(); +	load_jvc_decode(); +	load_sony_decode(); +	load_lirc_codec(); + +	/* If needed, we may later add some init code. In this case, +	   it is needed to change the CONFIG_MODULE test at rc-core.h +	 */ +} +#endif + +void ir_raw_init(void) +{ +#ifdef MODULE +	INIT_WORK(&wq_load, init_decoders); +	schedule_work(&wq_load); +#endif +}  |