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Release 4.11 drivers/media/rc/ir-jvc-decoder.c

Directory: drivers/media/rc
/* 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 (!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, RC_TYPE_JVC, 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; }

Contributors

PersonTokensPropCommitsCommitProp
David Härdeman56291.23%457.14%
Maxim Levitsky528.44%228.57%
Mauro Carvalho Chehab20.32%114.29%
Total616100.00%7100.00%

static const struct ir_raw_timings_pd ir_jvc_timings = { .header_pulse = JVC_HEADER_PULSE, .header_space = JVC_HEADER_SPACE, .bit_pulse = JVC_BIT_PULSE, .bit_space[0] = JVC_BIT_0_SPACE, .bit_space[1] = JVC_BIT_1_SPACE, .trailer_pulse = JVC_TRAILER_PULSE, .trailer_space = JVC_TRAILER_SPACE, .msb_first = 1, }; /** * ir_jvc_encode() - Encode a scancode as a stream of raw events * * @protocol: protocol to encode * @scancode: scancode to encode * @events: array of raw ir events to write into * @max: maximum size of @events * * Returns: The number of events written. * -ENOBUFS if there isn't enough space in the array to fit the * encoding. In this case all @max events will have been written. */
static int ir_jvc_encode(enum rc_type protocol, u32 scancode, struct ir_raw_event *events, unsigned int max) { struct ir_raw_event *e = events; int ret; u32 raw = (bitrev8((scancode >> 8) & 0xff) << 8) | (bitrev8((scancode >> 0) & 0xff) << 0); ret = ir_raw_gen_pd(&e, max, &ir_jvc_timings, JVC_NBITS, raw); if (ret < 0) return ret; return e - events; }

Contributors

PersonTokensPropCommitsCommitProp
Sean Young96100.00%1100.00%
Total96100.00%1100.00%

static struct ir_raw_handler jvc_handler = { .protocols = RC_BIT_JVC, .decode = ir_jvc_decode, .encode = ir_jvc_encode, };
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; }

Contributors

PersonTokensPropCommitsCommitProp
David Härdeman24100.00%1100.00%
Total24100.00%1100.00%


static void __exit ir_jvc_decode_exit(void) { ir_raw_handler_unregister(&jvc_handler); }

Contributors

PersonTokensPropCommitsCommitProp
David Härdeman15100.00%1100.00%
Total15100.00%1100.00%

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");

Overall Contributors

PersonTokensPropCommitsCommitProp
David Härdeman70576.55%650.00%
Sean Young15616.94%18.33%
Maxim Levitsky545.86%216.67%
Paul Gortmaker30.33%18.33%
Mauro Carvalho Chehab30.33%216.67%
Total921100.00%12100.00%
Directory: drivers/media/rc
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