linux/drivers/media/rc/ir-jvc-decoder.c
David Härdeman 9719afae5e [media] rc-core: don't treat dev->rc_map.rc_type as a bitmap
store_protocols() treats dev->rc_map.rc_type as a bitmap which is wrong for
two reasons. First of all, it is pretty bogus to change the protocol type of
the keymap just because the hardware has been asked to decode a different
protocol.
Second, dev->rc_map.rc_type is an enum (i.e. a single protocol) as pointed
out by James Hogan <james.hogan@imgtec.com>.
Fix both issues by introducing a separate enabled_protocols member to
struct rc_dev.

Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2013-03-23 11:25:54 -03:00

200 lines
4.7 KiB
C

/* ir-jvc-decoder.c - handle JVC 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 JVC_NBITS 16 /* dev(8) + func(8) */
#define JVC_UNIT 525000 /* ns */
#define JVC_HEADER_PULSE (16 * JVC_UNIT) /* lack of header -> repeat */
#define JVC_HEADER_SPACE (8 * JVC_UNIT)
#define JVC_BIT_PULSE (1 * JVC_UNIT)
#define JVC_BIT_0_SPACE (1 * JVC_UNIT)
#define JVC_BIT_1_SPACE (3 * JVC_UNIT)
#define JVC_TRAILER_PULSE (1 * JVC_UNIT)
#define JVC_TRAILER_SPACE (35 * JVC_UNIT)
enum jvc_state {
STATE_INACTIVE,
STATE_HEADER_SPACE,
STATE_BIT_PULSE,
STATE_BIT_SPACE,
STATE_TRAILER_PULSE,
STATE_TRAILER_SPACE,
STATE_CHECK_REPEAT,
};
/**
* ir_jvc_decode() - Decode one JVC pulse or space
* @dev: the struct rc_dev descriptor of the device
* @duration: the struct ir_raw_event descriptor of the pulse/space
*
* This function returns -EINVAL if the pulse violates the state machine
*/
static int ir_jvc_decode(struct rc_dev *dev, struct ir_raw_event ev)
{
struct jvc_dec *data = &dev->raw->jvc;
if (!(dev->enabled_protocols & RC_BIT_JVC))
return 0;
if (!is_timing_event(ev)) {
if (ev.reset)
data->state = STATE_INACTIVE;
return 0;
}
if (!geq_margin(ev.duration, JVC_UNIT, JVC_UNIT / 2))
goto out;
IR_dprintk(2, "JVC decode started at state %d (%uus %s)\n",
data->state, TO_US(ev.duration), TO_STR(ev.pulse));
again:
switch (data->state) {
case STATE_INACTIVE:
if (!ev.pulse)
break;
if (!eq_margin(ev.duration, JVC_HEADER_PULSE, JVC_UNIT / 2))
break;
data->count = 0;
data->first = true;
data->toggle = !data->toggle;
data->state = STATE_HEADER_SPACE;
return 0;
case STATE_HEADER_SPACE:
if (ev.pulse)
break;
if (!eq_margin(ev.duration, JVC_HEADER_SPACE, JVC_UNIT / 2))
break;
data->state = STATE_BIT_PULSE;
return 0;
case STATE_BIT_PULSE:
if (!ev.pulse)
break;
if (!eq_margin(ev.duration, JVC_BIT_PULSE, JVC_UNIT / 2))
break;
data->state = STATE_BIT_SPACE;
return 0;
case STATE_BIT_SPACE:
if (ev.pulse)
break;
data->bits <<= 1;
if (eq_margin(ev.duration, JVC_BIT_1_SPACE, JVC_UNIT / 2)) {
data->bits |= 1;
decrease_duration(&ev, JVC_BIT_1_SPACE);
} else if (eq_margin(ev.duration, JVC_BIT_0_SPACE, JVC_UNIT / 2))
decrease_duration(&ev, JVC_BIT_0_SPACE);
else
break;
data->count++;
if (data->count == JVC_NBITS)
data->state = STATE_TRAILER_PULSE;
else
data->state = STATE_BIT_PULSE;
return 0;
case STATE_TRAILER_PULSE:
if (!ev.pulse)
break;
if (!eq_margin(ev.duration, JVC_TRAILER_PULSE, JVC_UNIT / 2))
break;
data->state = STATE_TRAILER_SPACE;
return 0;
case STATE_TRAILER_SPACE:
if (ev.pulse)
break;
if (!geq_margin(ev.duration, JVC_TRAILER_SPACE, JVC_UNIT / 2))
break;
if (data->first) {
u32 scancode;
scancode = (bitrev8((data->bits >> 8) & 0xff) << 8) |
(bitrev8((data->bits >> 0) & 0xff) << 0);
IR_dprintk(1, "JVC scancode 0x%04x\n", scancode);
rc_keydown(dev, scancode, data->toggle);
data->first = false;
data->old_bits = data->bits;
} else if (data->bits == data->old_bits) {
IR_dprintk(1, "JVC repeat\n");
rc_repeat(dev);
} else {
IR_dprintk(1, "JVC invalid repeat msg\n");
break;
}
data->count = 0;
data->state = STATE_CHECK_REPEAT;
return 0;
case STATE_CHECK_REPEAT:
if (!ev.pulse)
break;
if (eq_margin(ev.duration, JVC_HEADER_PULSE, JVC_UNIT / 2))
data->state = STATE_INACTIVE;
else
data->state = STATE_BIT_PULSE;
goto again;
}
out:
IR_dprintk(1, "JVC 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 jvc_handler = {
.protocols = RC_BIT_JVC,
.decode = ir_jvc_decode,
};
static int __init ir_jvc_decode_init(void)
{
ir_raw_handler_register(&jvc_handler);
printk(KERN_INFO "IR JVC protocol handler initialized\n");
return 0;
}
static void __exit ir_jvc_decode_exit(void)
{
ir_raw_handler_unregister(&jvc_handler);
}
module_init(ir_jvc_decode_init);
module_exit(ir_jvc_decode_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
MODULE_DESCRIPTION("JVC IR protocol decoder");