Commit 721074b0 authored by Patrick Lerda's avatar Patrick Lerda Committed by Mauro Carvalho Chehab
Browse files

media: rc: rcmm decoder and encoder 



media: add support for RCMM infrared remote controls.

Signed-off-by: default avatarPatrick Lerda <patrick9876@free.fr>
Signed-off-by: default avatarSean Young <sean@mess.org>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent 12aceee1

Documentation/media/lirc.h.rst.exceptions

+3 −0
Original line number Diff line number Diff line
@@ -60,6 +60,9 @@ ignore symbol RC_PROTO_SHARP 
ignore symbol RC_PROTO_XMP

ignore symbol RC_PROTO_CEC

ignore symbol RC_PROTO_IMON

ignore symbol RC_PROTO_RCMM12

ignore symbol RC_PROTO_RCMM24

ignore symbol RC_PROTO_RCMM32



# Undocumented macros

MAINTAINERS

+5 −0
Original line number Diff line number Diff line
@@ -16536,6 +16536,11 @@ M: David Härdeman <david@hardeman.nu> 
S:	Maintained

F:	drivers/media/rc/winbond-cir.c



RCMM REMOTE CONTROLS DECODER

M:	Patrick Lerda <patrick9876@free.fr>

S:	Maintained

F:	drivers/media/rc/ir-rcmm-decoder.c



WINSYSTEMS EBC-C384 WATCHDOG DRIVER

M:	William Breathitt Gray <vilhelm.gray@gmail.com>

L:	linux-watchdog@vger.kernel.org

drivers/media/rc/Kconfig

+13 −0
Original line number Diff line number Diff line
@@ -133,6 +133,19 @@ config IR_IMON_DECODER 
	   remote control and you would like to use it with a raw IR

	   receiver, or if you wish to use an encoder to transmit this IR.



config IR_RCMM_DECODER

	tristate "Enable IR raw decoder for the RC-MM protocol"

	depends on RC_CORE

	help

	   Enable this option when you have IR with RC-MM protocol, and

	   you need the software decoder. The driver supports 12,

	   24 and 32 bits RC-MM variants. You can enable or disable the

	   different modes using the following RC protocol keywords:

	   'rc-mm-12', 'rc-mm-24' and 'rc-mm-32'.



	   To compile this driver as a module, choose M here: the module

	   will be called ir-rcmm-decoder.



endif #RC_DECODERS



menuconfig RC_DEVICES

drivers/media/rc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ obj-$(CONFIG_IR_SHARP_DECODER) += ir-sharp-decoder.o 
obj-$(CONFIG_IR_MCE_KBD_DECODER) += ir-mce_kbd-decoder.o

obj-$(CONFIG_IR_XMP_DECODER) += ir-xmp-decoder.o

obj-$(CONFIG_IR_IMON_DECODER) += ir-imon-decoder.o

obj-$(CONFIG_IR_RCMM_DECODER) += ir-rcmm-decoder.o



# stand-alone IR receivers/transmitters

obj-$(CONFIG_RC_ATI_REMOTE) += ati_remote.o

drivers/media/rc/ir-rcmm-decoder.c

0 → 100644
+254 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+

// ir-rcmm-decoder.c - A decoder for the RCMM IR protocol

//

// Copyright (C) 2018 by Patrick Lerda <patrick9876@free.fr>



#include "rc-core-priv.h"

#include <linux/module.h>

#include <linux/version.h>



#define RCMM_UNIT		166667	/* nanosecs */

#define RCMM_PREFIX_PULSE	416666  /* 166666.666666666*2.5 */

#define RCMM_PULSE_0            277777  /* 166666.666666666*(1+2/3) */

#define RCMM_PULSE_1            444444  /* 166666.666666666*(2+2/3) */

#define RCMM_PULSE_2            611111  /* 166666.666666666*(3+2/3) */

#define RCMM_PULSE_3            777778  /* 166666.666666666*(4+2/3) */



enum rcmm_state {

	STATE_INACTIVE,

	STATE_LOW,

	STATE_BUMP,

	STATE_VALUE,

	STATE_FINISHED,

};



static bool rcmm_mode(const struct rcmm_dec *data)

{

	return !((0x000c0000 & data->bits) == 0x000c0000);

}



static int rcmm_miscmode(struct rc_dev *dev, struct rcmm_dec *data)

{

	switch (data->count) {

	case 24:

		if (dev->enabled_protocols & RC_PROTO_BIT_RCMM24) {

			rc_keydown(dev, RC_PROTO_RCMM24, data->bits, 0);

			data->state = STATE_INACTIVE;

			return 0;

		}

		return -1;



	case 12:

		if (dev->enabled_protocols & RC_PROTO_BIT_RCMM12) {

			rc_keydown(dev, RC_PROTO_RCMM12, data->bits, 0);

			data->state = STATE_INACTIVE;

			return 0;

		}

		return -1;

	}



	return -1;

}



/**

 * ir_rcmm_decode() - Decode one RCMM 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_rcmm_decode(struct rc_dev *dev, struct ir_raw_event ev)

{

	struct rcmm_dec *data = &dev->raw->rcmm;

	u32 scancode;

	u8 toggle;

	int value;



	if (!(dev->enabled_protocols & (RC_PROTO_BIT_RCMM32 |

							RC_PROTO_BIT_RCMM24 |

							RC_PROTO_BIT_RCMM12)))

		return 0;



	if (!is_timing_event(ev)) {

		if (ev.reset)

			data->state = STATE_INACTIVE;

		return 0;

	}



	switch (data->state) {

	case STATE_INACTIVE:

		if (!ev.pulse)

			break;



		if (!eq_margin(ev.duration, RCMM_PREFIX_PULSE, RCMM_UNIT / 2))

			break;



		data->state = STATE_LOW;

		data->count = 0;

		data->bits  = 0;

		return 0;



	case STATE_LOW:

		if (ev.pulse)

			break;



		if (!eq_margin(ev.duration, RCMM_PULSE_0, RCMM_UNIT / 2))

			break;



		data->state = STATE_BUMP;

		return 0;



	case STATE_BUMP:

		if (!ev.pulse)

			break;



		if (!eq_margin(ev.duration, RCMM_UNIT, RCMM_UNIT / 2))

			break;



		data->state = STATE_VALUE;

		return 0;



	case STATE_VALUE:

		if (ev.pulse)

			break;



		if (eq_margin(ev.duration, RCMM_PULSE_0, RCMM_UNIT / 2))

			value = 0;

		else if (eq_margin(ev.duration, RCMM_PULSE_1, RCMM_UNIT / 2))

			value = 1;

		else if (eq_margin(ev.duration, RCMM_PULSE_2, RCMM_UNIT / 2))

			value = 2;

		else if (eq_margin(ev.duration, RCMM_PULSE_3, RCMM_UNIT / 2))

			value = 3;

		else

			value = -1;



		if (value == -1) {

			if (!rcmm_miscmode(dev, data))

				return 0;

			break;

		}



		data->bits <<= 2;

		data->bits |= value;



		data->count += 2;



		if (data->count < 32)

			data->state = STATE_BUMP;

		else

			data->state = STATE_FINISHED;



		return 0;



	case STATE_FINISHED:

		if (!ev.pulse)

			break;



		if (!eq_margin(ev.duration, RCMM_UNIT, RCMM_UNIT / 2))

			break;



		if (rcmm_mode(data)) {

			toggle = !!(0x8000 & data->bits);

			scancode = data->bits & ~0x8000;

		} else {

			toggle = 0;

			scancode = data->bits;

		}



		if (dev->enabled_protocols & RC_PROTO_BIT_RCMM32) {

			rc_keydown(dev, RC_PROTO_RCMM32, scancode, toggle);

			data->state = STATE_INACTIVE;

			return 0;

		}



		break;

	}



	data->state = STATE_INACTIVE;

	return -EINVAL;

}



static const int rcmmspace[] = {

	RCMM_PULSE_0,

	RCMM_PULSE_1,

	RCMM_PULSE_2,

	RCMM_PULSE_3,

};



static int ir_rcmm_rawencoder(struct ir_raw_event **ev, unsigned int max,

			      unsigned int n, u32 data)

{

	int i;

	int ret;



	ret = ir_raw_gen_pulse_space(ev, &max, RCMM_PREFIX_PULSE, RCMM_PULSE_0);

	if (ret)

		return ret;



	for (i = n - 2; i >= 0; i -= 2) {

		const unsigned int space = rcmmspace[(data >> i) & 3];



		ret = ir_raw_gen_pulse_space(ev, &max, RCMM_UNIT, space);

		if (ret)

			return ret;

	}



	return ir_raw_gen_pulse_space(ev, &max, RCMM_UNIT, RCMM_PULSE_3 * 2);

}



static int ir_rcmm_encode(enum rc_proto protocol, u32 scancode,

			  struct ir_raw_event *events, unsigned int max)

{

	struct ir_raw_event *e = events;

	int ret;



	switch (protocol) {

	case RC_PROTO_RCMM32:

		ret = ir_rcmm_rawencoder(&e, max, 32, scancode);

		break;

	case RC_PROTO_RCMM24:

		ret = ir_rcmm_rawencoder(&e, max, 24, scancode);

		break;

	case RC_PROTO_RCMM12:

		ret = ir_rcmm_rawencoder(&e, max, 12, scancode);

		break;

	default:

		ret = -EINVAL;

	}



	if (ret < 0)

		return ret;



	return e - events;

}



static struct ir_raw_handler rcmm_handler = {

	.protocols	= RC_PROTO_BIT_RCMM32 |

			  RC_PROTO_BIT_RCMM24 |

			  RC_PROTO_BIT_RCMM12,

	.decode		= ir_rcmm_decode,

	.encode         = ir_rcmm_encode,

	.carrier        = 36000,

	.min_timeout	= RCMM_PULSE_3 + RCMM_UNIT,

};



static int __init ir_rcmm_decode_init(void)

{

	ir_raw_handler_register(&rcmm_handler);



	pr_info("IR RCMM protocol handler initialized\n");

	return 0;

}



static void __exit ir_rcmm_decode_exit(void)

{

	ir_raw_handler_unregister(&rcmm_handler);

}



module_init(ir_rcmm_decode_init);

module_exit(ir_rcmm_decode_exit);



MODULE_LICENSE("GPL");

MODULE_AUTHOR("Patrick Lerda");

MODULE_DESCRIPTION("RCMM IR protocol decoder");