blob: fb914342cf4db3f2f0f56035ed0fbb78de0872aa [file] [log] [blame]
/* ir-sony-decoder.c - handle Sony IR Pulse/Space protocol
*
* Copyright (C) 2010 by David Härdeman <david@hardeman.nu>
*
* 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/bitrev.h>
#include <linux/module.h>
#include "rc-core-priv.h"
#define SONY_UNIT 600000 /* ns */
#define SONY_HEADER_PULSE (4 * SONY_UNIT)
#define SONY_HEADER_SPACE (1 * SONY_UNIT)
#define SONY_BIT_0_PULSE (1 * SONY_UNIT)
#define SONY_BIT_1_PULSE (2 * SONY_UNIT)
#define SONY_BIT_SPACE (1 * SONY_UNIT)
#define SONY_TRAILER_SPACE (10 * SONY_UNIT) /* minimum */
enum sony_state {
STATE_INACTIVE,
STATE_HEADER_SPACE,
STATE_BIT_PULSE,
STATE_BIT_SPACE,
STATE_FINISHED,
};
/**
* ir_sony_decode() - Decode one Sony pulse or space
* @dev: the struct rc_dev descriptor of the device
* @ev: the struct ir_raw_event descriptor of the pulse/space
*
* This function returns -EINVAL if the pulse violates the state machine
*/
static int ir_sony_decode(struct rc_dev *dev, struct ir_raw_event ev)
{
struct sony_dec *data = &dev->raw->sony;
u32 scancode;
u8 device, subdevice, function;
if (!(dev->raw->enabled_protocols &
(RC_BIT_SONY12 | RC_BIT_SONY15 | RC_BIT_SONY20)))
return 0;
if (!is_timing_event(ev)) {
if (ev.reset)
data->state = STATE_INACTIVE;
return 0;
}
if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2))
goto out;
IR_dprintk(2, "Sony decode started at state %d (%uus %s)\n",
data->state, TO_US(ev.duration), TO_STR(ev.pulse));
switch (data->state) {
case STATE_INACTIVE:
if (!ev.pulse)
break;
if (!eq_margin(ev.duration, SONY_HEADER_PULSE, SONY_UNIT / 2))
break;
data->count = 0;
data->state = STATE_HEADER_SPACE;
return 0;
case STATE_HEADER_SPACE:
if (ev.pulse)
break;
if (!eq_margin(ev.duration, SONY_HEADER_SPACE, SONY_UNIT / 2))
break;
data->state = STATE_BIT_PULSE;
return 0;
case STATE_BIT_PULSE:
if (!ev.pulse)
break;
data->bits <<= 1;
if (eq_margin(ev.duration, SONY_BIT_1_PULSE, SONY_UNIT / 2))
data->bits |= 1;
else if (!eq_margin(ev.duration, SONY_BIT_0_PULSE, SONY_UNIT / 2))
break;
data->count++;
data->state = STATE_BIT_SPACE;
return 0;
case STATE_BIT_SPACE:
if (ev.pulse)
break;
if (!geq_margin(ev.duration, SONY_BIT_SPACE, SONY_UNIT / 2))
break;
decrease_duration(&ev, SONY_BIT_SPACE);
if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2)) {
data->state = STATE_BIT_PULSE;
return 0;
}
data->state = STATE_FINISHED;
/* Fall through */
case STATE_FINISHED:
if (ev.pulse)
break;
if (!geq_margin(ev.duration, SONY_TRAILER_SPACE, SONY_UNIT / 2))
break;
switch (data->count) {
case 12:
if (!(dev->raw->enabled_protocols & RC_BIT_SONY12)) {
data->state = STATE_INACTIVE;
return 0;
}
device = bitrev8((data->bits << 3) & 0xF8);
subdevice = 0;
function = bitrev8((data->bits >> 4) & 0xFE);
break;
case 15:
if (!(dev->raw->enabled_protocols & RC_BIT_SONY15)) {
data->state = STATE_INACTIVE;
return 0;
}
device = bitrev8((data->bits >> 0) & 0xFF);
subdevice = 0;
function = bitrev8((data->bits >> 7) & 0xFE);
break;
case 20:
if (!(dev->raw->enabled_protocols & RC_BIT_SONY20)) {
data->state = STATE_INACTIVE;
return 0;
}
device = bitrev8((data->bits >> 5) & 0xF8);
subdevice = bitrev8((data->bits >> 0) & 0xFF);
function = bitrev8((data->bits >> 12) & 0xFE);
break;
default:
IR_dprintk(1, "Sony invalid bitcount %u\n", data->count);
goto out;
}
scancode = device << 16 | subdevice << 8 | function;
IR_dprintk(1, "Sony(%u) scancode 0x%05x\n", data->count, scancode);
rc_keydown(dev, scancode, 0);
data->state = STATE_INACTIVE;
return 0;
}
out:
IR_dprintk(1, "Sony decode failed at state %d (%uus %s)\n",
data->state, TO_US(ev.duration), TO_STR(ev.pulse));
data->state = STATE_INACTIVE;
return -EINVAL;
}
static struct ir_raw_handler sony_handler = {
.protocols = RC_BIT_SONY12 | RC_BIT_SONY15 | RC_BIT_SONY20,
.decode = ir_sony_decode,
};
static int __init ir_sony_decode_init(void)
{
ir_raw_handler_register(&sony_handler);
printk(KERN_INFO "IR Sony protocol handler initialized\n");
return 0;
}
static void __exit ir_sony_decode_exit(void)
{
ir_raw_handler_unregister(&sony_handler);
}
module_init(ir_sony_decode_init);
module_exit(ir_sony_decode_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
MODULE_DESCRIPTION("Sony IR protocol decoder");