/* ir-raw-event.c - handle IR Pulse/Space event
*
* 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/workqueue.h>
#include <linux/spinlock.h>
#include <linux/sched.h>
#include "ir-core-priv.h"
/* Define the max number of pulse/space transitions to buffer */
#define MAX_IR_EVENT_SIZE 512
/* Used to handle IR raw handler extensions */
static LIST_HEAD(ir_raw_handler_list);
static DEFINE_SPINLOCK(ir_raw_handler_lock);
/**
* RUN_DECODER() - runs an operation on all IR decoders
* @ops: IR raw handler operation to be called
* @arg: arguments to be passed to the callback
*
* Calls ir_raw_handler::ops for all registered IR handlers. It prevents
* new decode addition/removal while running, by locking ir_raw_handler_lock
* mutex. If an error occurs, it stops the ops. Otherwise, it returns a sum
* of the return codes.
*/
#define RUN_DECODER(ops, ...) ({ \
struct ir_raw_handler *_ir_raw_handler; \
int _sumrc = 0, _rc; \
spin_lock(&ir_raw_handler_lock); \
list_for_each_entry(_ir_raw_handler, &ir_raw_handler_list, list) { \
if (_ir_raw_handler->ops) { \
_rc = _ir_raw_handler->ops(__VA_ARGS__); \
if (_rc < 0) \
break; \
_sumrc += _rc; \
} \
} \
spin_unlock(&ir_raw_handler_lock); \
_sumrc; \
})
#ifdef MODULE
/* Used to load the decoders */
static struct work_struct wq_load;
#endif
static void ir_raw_event_work(struct work_struct *work)
{
struct ir_raw_event ev;
struct ir_raw_event_ctrl *raw =
container_of(work, struct ir_raw_event_ctrl, rx_work);
while (kfifo_out(&raw->kfifo, &ev, sizeof(ev)) == sizeof(ev))
RUN_DECODER(decode, raw->input_dev, ev);
}
int ir_raw_event_register(struct input_dev *input_dev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
int rc;
ir->raw = kzalloc(sizeof(*ir->raw), GFP_KERNEL);
if (!ir->raw)
return -ENOMEM;
ir->raw->input_dev = input_dev;
INIT_WORK(&ir->raw->rx_work, ir_raw_event_work);
rc = kfifo_alloc(&ir->raw->kfifo, sizeof(s64) * MAX_IR_EVENT_SIZE,
GFP_KERNEL);
if (rc < 0) {
kfree(ir->raw);
ir->raw = NULL;
return rc;
}
rc = RUN_DECODER(raw_register, input_dev);
if (rc < 0) {
kfifo_free(&ir->raw->kfifo);
kfree(ir->raw);
ir->raw = NULL;
return rc;
}
return rc;
}
void ir_raw_event_unregister(struct input_dev *input_dev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
if (!ir->raw)
return;
cancel_work_sync(&ir->raw->rx_work);
RUN_DECODER(raw_unregister, input_dev);
kfifo_free(&ir->raw->kfifo);
kfree(ir->raw);
ir->raw = NULL;
}
/**
* ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
* @input_dev: the struct input_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 input_dev *input_dev, struct ir_raw_event *ev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
if (!ir->raw)
return -EINVAL;
if (kfifo_in(&ir->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
* @input_dev: the struct input_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 input_dev *input_dev, enum raw_event_type type)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
ktime_t now;
s64 delta; /* ns */
struct ir_raw_event ev;
int rc = 0;
if (!ir->raw)
return -EINVAL;
now = ktime_get();
delta = ktime_to_ns(ktime_sub(now, ir->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 || !ir->raw->last_type)
type |= IR_START_EVENT;
else
ev.duration = delta;
if (type & IR_START_EVENT)
ir_raw_event_reset(input_dev);
else if (ir->raw->last_type & IR_SPACE) {
ev.pulse = false;
rc = ir_raw_event_store(input_dev, &ev);
} else if (ir->raw->last_type & IR_PULSE) {
ev.pulse = true;
rc = ir_raw_event_store(input_dev, &ev);
} else
return 0;
ir->raw->last_event = now;
ir->raw->last_type = type;
return rc;
}
EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);
/**
* ir_raw_event_handle() - schedules the decoding of stored ir data
* @input_dev: the struct input_dev device descriptor
*
* This routine will signal the workqueue to start decoding stored ir data.
*/
void ir_raw_event_handle(struct input_dev *input_dev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
if (!ir->raw)
return;
schedule_work(&ir->raw->rx_work);
}
EXPORT_SYMBOL_GPL(ir_raw_event_handle);
/*
* Extension interface - used to register the IR decoders
*/
int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
{
spin_lock(&ir_raw_handler_lock);
list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
spin_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)
{
spin_lock(&ir_raw_handler_lock);
list_del(&ir_raw_handler->list);
spin_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();
/* If needed, we may later add some init code. In this case,
it is needed to change the CONFIG_MODULE test at ir-core.h
*/
}
#endif
void ir_raw_init(void)
{
#ifdef MODULE
INIT_WORK(&wq_load, init_decoders);
schedule_work(&wq_load);
#endif
}
