V4L/DVB: Add RC6 support to ir-core (784a4931) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/media/IR/Kconfig

+9 −0

Original line number	Diff line number	Diff line
		@@ -27,3 +27,12 @@ config IR_RC5_DECODER
		---help---
		Enable this option if you have IR with RC-5 protocol, and
		if the IR is decoded in software

		config IR_RC6_DECODER
		tristate "Enable IR raw decoder for the RC6 protocol"
		depends on IR_CORE
		default y

		---help---
		Enable this option if you have an infrared remote control which
		uses the RC6 protocol, and you need software decoding support.

drivers/media/IR/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -7,3 +7,4 @@ obj-$(CONFIG_IR_CORE) += ir-core.o
		obj-$(CONFIG_VIDEO_IR) += ir-common.o
		obj-$(CONFIG_IR_NEC_DECODER) += ir-nec-decoder.o
		obj-$(CONFIG_IR_RC5_DECODER) += ir-rc5-decoder.o
		obj-$(CONFIG_IR_RC6_DECODER) += ir-rc6-decoder.o

drivers/media/IR/ir-core-priv.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -108,4 +108,11 @@ void ir_raw_init(void);
		#define load_rc5_decode() 0
		#endif

		/* from ir-rc6-decoder.c */
		#ifdef CONFIG_IR_RC5_DECODER_MODULE
		#define load_rc6_decode() request_module("ir-rc6-decoder")
		#else
		#define load_rc6_decode() 0
		#endif

		#endif /* _IR_RAW_EVENT */

drivers/media/IR/ir-raw-event.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -226,6 +226,7 @@ static void init_decoders(struct work_struct *work)

		load_nec_decode();
		load_rc5_decode();
		load_rc6_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

drivers/media/IR/ir-rc6-decoder.c

0 → 100644

+412 −0

Original line number	Diff line number	Diff line
		/* ir-rc6-decoder.c - A decoder for the RC6 IR 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 "ir-core-priv.h"

		/*
		* This decoder currently supports:
		* RC6-0-16 (standard toggle bit in header)
		* RC6-6A-24 (no toggle bit)
		* RC6-6A-32 (MCE version with toggle bit in body)
		*/

		#define RC6_UNIT 444444 /* us */
		#define RC6_HEADER_NBITS 4 /* not including toggle bit */
		#define RC6_0_NBITS 16
		#define RC6_6A_SMALL_NBITS 24
		#define RC6_6A_LARGE_NBITS 32
		#define RC6_PREFIX_PULSE PULSE(6)
		#define RC6_PREFIX_SPACE SPACE(2)
		#define RC6_MODE_MASK 0x07 /* for the header bits */
		#define RC6_STARTBIT_MASK 0x08 /* for the header bits */
		#define RC6_6A_MCE_TOGGLE_MASK 0x8000 /* for the body bits */

		/* Used to register rc6_decoder clients */
		static LIST_HEAD(decoder_list);
		static DEFINE_SPINLOCK(decoder_lock);

		enum rc6_mode {
		RC6_MODE_0,
		RC6_MODE_6A,
		RC6_MODE_UNKNOWN,
		};

		enum rc6_state {
		STATE_INACTIVE,
		STATE_PREFIX_SPACE,
		STATE_HEADER_BIT_START,
		STATE_HEADER_BIT_END,
		STATE_TOGGLE_START,
		STATE_TOGGLE_END,
		STATE_BODY_BIT_START,
		STATE_BODY_BIT_END,
		STATE_FINISHED,
		};

		struct decoder_data {
		struct list_head list;
		struct ir_input_dev *ir_dev;
		int enabled:1;

		/* State machine control */
		enum rc6_state state;
		u8 header;
		u32 body;
		int last_unit;
		bool toggle;
		unsigned count;
		unsigned wanted_bits;
		};


		/**
		* get_decoder_data() - gets decoder data
		* @input_dev: input device
		*
		* Returns the struct decoder_data that corresponds to a device
		*/
		static struct decoder_data get_decoder_data(struct ir_input_dev ir_dev)
		{
		struct decoder_data *data = NULL;

		spin_lock(&decoder_lock);
		list_for_each_entry(data, &decoder_list, list) {
		if (data->ir_dev == ir_dev)
		break;
		}
		spin_unlock(&decoder_lock);
		return data;
		}

		static ssize_t store_enabled(struct device *d,
		struct device_attribute *mattr,
		const char *buf,
		size_t len)
		{
		unsigned long value;
		struct ir_input_dev *ir_dev = dev_get_drvdata(d);
		struct decoder_data *data = get_decoder_data(ir_dev);

		if (!data)
		return -EINVAL;

		if (strict_strtoul(buf, 10, &value) \|\| value > 1)
		return -EINVAL;

		data->enabled = value;

		return len;
		}

		static ssize_t show_enabled(struct device *d,
		struct device_attribute mattr, char buf)
		{
		struct ir_input_dev *ir_dev = dev_get_drvdata(d);
		struct decoder_data *data = get_decoder_data(ir_dev);

		if (!data)
		return -EINVAL;

		if (data->enabled)
		return sprintf(buf, "1\n");
		else
		return sprintf(buf, "0\n");
		}

		static DEVICE_ATTR(enabled, S_IRUGO \| S_IWUSR, show_enabled, store_enabled);

		static struct attribute *decoder_attributes[] = {
		&dev_attr_enabled.attr,
		NULL
		};

		static struct attribute_group decoder_attribute_group = {
		.name = "rc6_decoder",
		.attrs = decoder_attributes,
		};

		static enum rc6_mode rc6_mode(struct decoder_data *data) {
		switch (data->header & RC6_MODE_MASK) {
		case 0:
		return RC6_MODE_0;
		case 6:
		if (!data->toggle)
		return RC6_MODE_6A;
		/* fall through */
		default:
		return RC6_MODE_UNKNOWN;
		}
		}

		/**
		* ir_rc6_decode() - Decode one RC6 pulse or space
		* @input_dev: the struct input_dev descriptor of the device
		* @duration: duration of pulse/space in ns
		*
		* This function returns -EINVAL if the pulse violates the state machine
		*/
		static int ir_rc6_decode(struct input_dev *input_dev, s64 duration)
		{
		struct decoder_data *data;
		struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
		u32 scancode;
		u8 toggle;
		int u;

		data = get_decoder_data(ir_dev);
		if (!data)
		return -EINVAL;

		if (!data->enabled)
		return 0;

		if (IS_RESET(duration)) {
		data->state = STATE_INACTIVE;
		return 0;
		}

		u = TO_UNITS(duration, RC6_UNIT);
		if (DURATION(u) == 0)
		goto out;

		again:
		IR_dprintk(2, "RC6 decode started at state %i (%i units, %ius)\n",
		data->state, u, TO_US(duration));

		if (DURATION(u) == 0 && data->state != STATE_FINISHED)
		return 0;

		switch (data->state) {

		case STATE_INACTIVE:
		if (u >= RC6_PREFIX_PULSE - 1 && u <= RC6_PREFIX_PULSE + 1) {
		data->state = STATE_PREFIX_SPACE;
		data->count = 0;
		return 0;
		}
		break;

		case STATE_PREFIX_SPACE:
		if (u == RC6_PREFIX_SPACE) {
		data->state = STATE_HEADER_BIT_START;
		return 0;
		}
		break;

		case STATE_HEADER_BIT_START:
		if (DURATION(u) == 1) {
		data->header <<= 1;
		if (IS_PULSE(u))
		data->header \|= 1;
		data->count++;
		data->last_unit = u;
		data->state = STATE_HEADER_BIT_END;
		return 0;
		}
		break;

		case STATE_HEADER_BIT_END:
		if (IS_TRANSITION(u, data->last_unit)) {
		if (data->count == RC6_HEADER_NBITS)
		data->state = STATE_TOGGLE_START;
		else
		data->state = STATE_HEADER_BIT_START;

		DECREASE_DURATION(u, 1);
		goto again;
		}
		break;

		case STATE_TOGGLE_START:
		if (DURATION(u) == 2) {
		data->toggle = IS_PULSE(u);
		data->last_unit = u;
		data->state = STATE_TOGGLE_END;
		return 0;
		}
		break;

		case STATE_TOGGLE_END:
		if (IS_TRANSITION(u, data->last_unit) && DURATION(u) >= 2) {
		data->state = STATE_BODY_BIT_START;
		data->last_unit = u;
		DECREASE_DURATION(u, 2);
		data->count = 0;

		if (!(data->header & RC6_STARTBIT_MASK)) {
		IR_dprintk(1, "RC6 invalid start bit\n");
		break;
		}

		switch (rc6_mode(data)) {
		case RC6_MODE_0:
		data->wanted_bits = RC6_0_NBITS;
		break;
		case RC6_MODE_6A:
		/* This might look weird, but we basically
		check the value of the first body bit to
		determine the number of bits in mode 6A */
		if ((DURATION(u) == 0 && IS_SPACE(data->last_unit)) \|\| DURATION(u) > 0)
		data->wanted_bits = RC6_6A_LARGE_NBITS;
		else
		data->wanted_bits = RC6_6A_SMALL_NBITS;
		break;
		default:
		IR_dprintk(1, "RC6 unknown mode\n");
		goto out;
		}
		goto again;
		}
		break;

		case STATE_BODY_BIT_START:
		if (DURATION(u) == 1) {
		data->body <<= 1;
		if (IS_PULSE(u))
		data->body \|= 1;
		data->count++;
		data->last_unit = u;

		/*
		* If the last bit is one, a space will merge
		* with the silence after the command.
		*/
		if (IS_PULSE(u) && data->count == data->wanted_bits) {
		data->state = STATE_FINISHED;
		goto again;
		}

		data->state = STATE_BODY_BIT_END;
		return 0;
		}
		break;

		case STATE_BODY_BIT_END:
		if (IS_TRANSITION(u, data->last_unit)) {
		if (data->count == data->wanted_bits)
		data->state = STATE_FINISHED;
		else
		data->state = STATE_BODY_BIT_START;

		DECREASE_DURATION(u, 1);
		goto again;
		}
		break;

		case STATE_FINISHED:
		switch (rc6_mode(data)) {
		case RC6_MODE_0:
		scancode = data->body & 0xffff;
		toggle = data->toggle;
		IR_dprintk(1, "RC6(0) scancode 0x%04x (toggle: %u)\n",
		scancode, toggle);
		break;
		case RC6_MODE_6A:
		if (data->wanted_bits == RC6_6A_LARGE_NBITS) {
		toggle = data->body & RC6_6A_MCE_TOGGLE_MASK ? 1 : 0;
		scancode = data->body & ~RC6_6A_MCE_TOGGLE_MASK;
		} else {
		toggle = 0;
		scancode = data->body & 0xffffff;
		}

		IR_dprintk(1, "RC6(6A) scancode 0x%08x (toggle: %u)\n",
		scancode, toggle);
		break;
		default:
		IR_dprintk(1, "RC6 unknown mode\n");
		goto out;
		}

		ir_keydown(input_dev, scancode, toggle);
		data->state = STATE_INACTIVE;
		return 0;
		}

		out:
		IR_dprintk(1, "RC6 decode failed at state %i (%i units, %ius)\n",
		data->state, u, TO_US(duration));
		data->state = STATE_INACTIVE;
		return -EINVAL;
		}

		static int ir_rc6_register(struct input_dev *input_dev)
		{
		struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
		struct decoder_data *data;
		int rc;

		rc = sysfs_create_group(&ir_dev->dev.kobj, &decoder_attribute_group);
		if (rc < 0)
		return rc;

		data = kzalloc(sizeof(*data), GFP_KERNEL);
		if (!data) {
		sysfs_remove_group(&ir_dev->dev.kobj, &decoder_attribute_group);
		return -ENOMEM;
		}

		data->ir_dev = ir_dev;
		data->enabled = 1;

		spin_lock(&decoder_lock);
		list_add_tail(&data->list, &decoder_list);
		spin_unlock(&decoder_lock);

		return 0;
		}

		static int ir_rc6_unregister(struct input_dev *input_dev)
		{
		struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
		static struct decoder_data *data;

		data = get_decoder_data(ir_dev);
		if (!data)
		return 0;

		sysfs_remove_group(&ir_dev->dev.kobj, &decoder_attribute_group);

		spin_lock(&decoder_lock);
		list_del(&data->list);
		spin_unlock(&decoder_lock);

		return 0;
		}

		static struct ir_raw_handler rc6_handler = {
		.decode = ir_rc6_decode,
		.raw_register = ir_rc6_register,
		.raw_unregister = ir_rc6_unregister,
		};

		static int __init ir_rc6_decode_init(void)
		{
		ir_raw_handler_register(&rc6_handler);

		printk(KERN_INFO "IR RC6 protocol handler initialized\n");
		return 0;
		}

		static void __exit ir_rc6_decode_exit(void)
		{
		ir_raw_handler_unregister(&rc6_handler);
		}

		module_init(ir_rc6_decode_init);
		module_exit(ir_rc6_decode_exit);

		MODULE_LICENSE("GPL");
		MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
		MODULE_DESCRIPTION("RC6 IR protocol decoder");