drivers/media/IR/ir-functions.c - kernel/skids - Git at Google

 /*
  *
  * some common structs and functions to handle infrared remotes via
  * input layer ...
  *
  * (c) 2003 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
  *
  *  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; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  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.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */

 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/jiffies.h>
 #include <media/ir-common.h>
 #include "ir-core-priv.h"

 /* -------------------------------------------------------------------------- */

 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
 MODULE_LICENSE("GPL");

 static int repeat = 1;
 module_param(repeat, int, 0444);
 MODULE_PARM_DESC(repeat,"auto-repeat for IR keys (default: on)");

 /* -------------------------------------------------------------------------- */

 static void ir_input_key_event(struct input_dev *dev, struct ir_input_state *ir)
 {
 	if (KEY_RESERVED == ir->keycode) {
 		printk(KERN_INFO "%s: unknown key: key=0x%02x down=%d\n",
 		       dev->name, ir->ir_key, ir->keypressed);
 		return;
 	}
 	IR_dprintk(1,"%s: key event code=%d down=%d\n",
 		dev->name,ir->keycode,ir->keypressed);
 	input_report_key(dev,ir->keycode,ir->keypressed);
 	input_sync(dev);
 }

 /* -------------------------------------------------------------------------- */

 int ir_input_init(struct input_dev *dev, struct ir_input_state *ir,
 		  const u64 ir_type)
 {
 	ir->ir_type = ir_type;

 	if (repeat)
 		set_bit(EV_REP, dev->evbit);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(ir_input_init);


 void ir_input_nokey(struct input_dev *dev, struct ir_input_state *ir)
 {
 	if (ir->keypressed) {
 		ir->keypressed = 0;
 		ir_input_key_event(dev,ir);
 	}
 }
 EXPORT_SYMBOL_GPL(ir_input_nokey);

 void ir_input_keydown(struct input_dev *dev, struct ir_input_state *ir,
 		      u32 ir_key)
 {
 	u32 keycode = ir_g_keycode_from_table(dev, ir_key);

 	if (ir->keypressed && ir->keycode != keycode) {
 		ir->keypressed = 0;
 		ir_input_key_event(dev,ir);
 	}
 	if (!ir->keypressed) {
 		ir->ir_key  = ir_key;
 		ir->keycode = keycode;
 		ir->keypressed = 1;
 		ir_input_key_event(dev,ir);
 	}
 }
 EXPORT_SYMBOL_GPL(ir_input_keydown);

 /* -------------------------------------------------------------------------- */
 /* extract mask bits out of data and pack them into the result */
 u32 ir_extract_bits(u32 data, u32 mask)
 {
 	u32 vbit = 1, value = 0;

 	do {
 	    if (mask&1) {
 		if (data&1)
 			value |= vbit;
 		vbit<<=1;
 	    }
 	    data>>=1;
 	} while (mask>>=1);

 	return value;
 }
 EXPORT_SYMBOL_GPL(ir_extract_bits);

 static int inline getbit(u32 *samples, int bit)
 {
 	return (samples[bit/32] & (1 << (31-(bit%32)))) ? 1 : 0;
 }

 /* sump raw samples for visual debugging ;) */
 int ir_dump_samples(u32 *samples, int count)
 {
 	int i, bit, start;

 	printk(KERN_DEBUG "ir samples: ");
 	start = 0;
 	for (i = 0; i < count * 32; i++) {
 		bit = getbit(samples,i);
 		if (bit)
 			start = 1;
 		if (0 == start)
 			continue;
 		printk("%s", bit ? "#" : "_");
 	}
 	printk("\n");
 	return 0;
 }
 EXPORT_SYMBOL_GPL(ir_dump_samples);

 /* decode raw samples, pulse distance coding used by NEC remotes */
 int ir_decode_pulsedistance(u32 *samples, int count, int low, int high)
 {
 	int i,last,bit,len;
 	u32 curBit;
 	u32 value;

 	/* find start burst */
 	for (i = len = 0; i < count * 32; i++) {
 		bit = getbit(samples,i);
 		if (bit) {
 			len++;
 		} else {
 			if (len >= 29)
 				break;
 			len = 0;
 		}
 	}

 	/* start burst to short */
 	if (len < 29)
 		return 0xffffffff;

 	/* find start silence */
 	for (len = 0; i < count * 32; i++) {
 		bit = getbit(samples,i);
 		if (bit) {
 			break;
 		} else {
 			len++;
 		}
 	}

 	/* silence to short */
 	if (len < 7)
 		return 0xffffffff;

 	/* go decoding */
 	len   = 0;
 	last = 1;
 	value = 0; curBit = 1;
 	for (; i < count * 32; i++) {
 		bit  = getbit(samples,i);
 		if (last) {
 			if(bit) {
 				continue;
 			} else {
 				len = 1;
 			}
 		} else {
 			if (bit) {
 				if (len > (low + high) /2)
 					value |= curBit;
 				curBit <<= 1;
 				if (curBit == 1)
 					break;
 			} else {
 				len++;
 			}
 		}
 		last = bit;
 	}

 	return value;
 }
 EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);

 /* decode raw samples, biphase coding, used by rc5 for example */
 int ir_decode_biphase(u32 *samples, int count, int low, int high)
 {
 	int i,last,bit,len,flips;
 	u32 value;

 	/* find start bit (1) */
 	for (i = 0; i < 32; i++) {
 		bit = getbit(samples,i);
 		if (bit)
 			break;
 	}

 	/* go decoding */
 	len   = 0;
 	flips = 0;
 	value = 1;
 	for (; i < count * 32; i++) {
 		if (len > high)
 			break;
 		if (flips > 1)
 			break;
 		last = bit;
 		bit  = getbit(samples,i);
 		if (last == bit) {
 			len++;
 			continue;
 		}
 		if (len < low) {
 			len++;
 			flips++;
 			continue;
 		}
 		value <<= 1;
 		value |= bit;
 		flips = 0;
 		len   = 1;
 	}
 	return value;
 }
 EXPORT_SYMBOL_GPL(ir_decode_biphase);

 /* RC5 decoding stuff, moved from bttv-input.c to share it with
  * saa7134 */

 /* decode raw bit pattern to RC5 code */
 u32 ir_rc5_decode(unsigned int code)
 {
 	unsigned int org_code = code;
 	unsigned int pair;
 	unsigned int rc5 = 0;
 	int i;

 	for (i = 0; i < 14; ++i) {
 		pair = code & 0x3;
 		code >>= 2;

 		rc5 <<= 1;
 		switch (pair) {
 		case 0:
 		case 2:
 			break;
 		case 1:
 			rc5 |= 1;
 			break;
 		case 3:
 			IR_dprintk(1, "ir-common: ir_rc5_decode(%x) bad code\n", org_code);
 			return 0;
 		}
 	}
 	IR_dprintk(1, "ir-common: code=%x, rc5=%x, start=%x, toggle=%x, address=%x, "
 		"instr=%x\n", rc5, org_code, RC5_START(rc5),
 		RC5_TOGGLE(rc5), RC5_ADDR(rc5), RC5_INSTR(rc5));
 	return rc5;
 }
 EXPORT_SYMBOL_GPL(ir_rc5_decode);

 void ir_rc5_timer_end(unsigned long data)
 {
 	struct card_ir *ir = (struct card_ir *)data;
 	struct timeval tv;
 	unsigned long current_jiffies, timeout;
 	u32 gap;
 	u32 rc5 = 0;

 	/* get time */
 	current_jiffies = jiffies;
 	do_gettimeofday(&tv);

 	/* avoid overflow with gap >1s */
 	if (tv.tv_sec - ir->base_time.tv_sec > 1) {
 		gap = 200000;
 	} else {
 		gap = 1000000 * (tv.tv_sec - ir->base_time.tv_sec) +
 		    tv.tv_usec - ir->base_time.tv_usec;
 	}

 	/* signal we're ready to start a new code */
 	ir->active = 0;

 	/* Allow some timer jitter (RC5 is ~24ms anyway so this is ok) */
 	if (gap < 28000) {
 		IR_dprintk(1, "ir-common: spurious timer_end\n");
 		return;
 	}

 	if (ir->last_bit < 20) {
 		/* ignore spurious codes (caused by light/other remotes) */
 		IR_dprintk(1, "ir-common: short code: %x\n", ir->code);
 	} else {
 		ir->code = (ir->code << ir->shift_by) | 1;
 		rc5 = ir_rc5_decode(ir->code);

 		/* two start bits? */
 		if (RC5_START(rc5) != ir->start) {
 			IR_dprintk(1, "ir-common: rc5 start bits invalid: %u\n", RC5_START(rc5));

 			/* right address? */
 		} else if (RC5_ADDR(rc5) == ir->addr) {
 			u32 toggle = RC5_TOGGLE(rc5);
 			u32 instr = RC5_INSTR(rc5);

 			/* Good code, decide if repeat/repress */
 			if (toggle != RC5_TOGGLE(ir->last_rc5) ||
 			    instr != RC5_INSTR(ir->last_rc5)) {
 				IR_dprintk(1, "ir-common: instruction %x, toggle %x\n", instr,
 					toggle);
 				ir_input_nokey(ir->dev, &ir->ir);
 				ir_input_keydown(ir->dev, &ir->ir, instr);
 			}

 			/* Set/reset key-up timer */
 			timeout = current_jiffies +
 				  msecs_to_jiffies(ir->rc5_key_timeout);
 			mod_timer(&ir->timer_keyup, timeout);

 			/* Save code for repeat test */
 			ir->last_rc5 = rc5;
 		}
 	}
 }
 EXPORT_SYMBOL_GPL(ir_rc5_timer_end);

 void ir_rc5_timer_keyup(unsigned long data)
 {
 	struct card_ir *ir = (struct card_ir *)data;

 	IR_dprintk(1, "ir-common: key released\n");
 	ir_input_nokey(ir->dev, &ir->ir);
 }
 EXPORT_SYMBOL_GPL(ir_rc5_timer_keyup);
	/*
	*
	* some common structs and functions to handle infrared remotes via
	* input layer ...
	*
	* (c) 2003 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
	*
	* 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; either version 2 of the License, or
	* (at your option) any later version.
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/jiffies.h>
	#include <media/ir-common.h>
	#include "ir-core-priv.h"

	/* -------------------------------------------------------------------------- */

	MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
	MODULE_LICENSE("GPL");

	static int repeat = 1;
	module_param(repeat, int, 0444);
	MODULE_PARM_DESC(repeat,"auto-repeat for IR keys (default: on)");

	/* -------------------------------------------------------------------------- */

	static void ir_input_key_event(struct input_dev dev, struct ir_input_state ir)
	{
	if (KEY_RESERVED == ir->keycode) {
	printk(KERN_INFO "%s: unknown key: key=0x%02x down=%d\n",
	dev->name, ir->ir_key, ir->keypressed);
	return;
	}
	IR_dprintk(1,"%s: key event code=%d down=%d\n",
	dev->name,ir->keycode,ir->keypressed);
	input_report_key(dev,ir->keycode,ir->keypressed);
	input_sync(dev);
	}

	/* -------------------------------------------------------------------------- */

	int ir_input_init(struct input_dev dev, struct ir_input_state ir,
	const u64 ir_type)
	{
	ir->ir_type = ir_type;

	if (repeat)
	set_bit(EV_REP, dev->evbit);

	return 0;
	}
	EXPORT_SYMBOL_GPL(ir_input_init);


	void ir_input_nokey(struct input_dev dev, struct ir_input_state ir)
	{
	if (ir->keypressed) {
	ir->keypressed = 0;
	ir_input_key_event(dev,ir);
	}
	}
	EXPORT_SYMBOL_GPL(ir_input_nokey);

	void ir_input_keydown(struct input_dev dev, struct ir_input_state ir,
	u32 ir_key)
	{
	u32 keycode = ir_g_keycode_from_table(dev, ir_key);

	if (ir->keypressed && ir->keycode != keycode) {
	ir->keypressed = 0;
	ir_input_key_event(dev,ir);
	}
	if (!ir->keypressed) {
	ir->ir_key = ir_key;
	ir->keycode = keycode;
	ir->keypressed = 1;
	ir_input_key_event(dev,ir);
	}
	}
	EXPORT_SYMBOL_GPL(ir_input_keydown);

	/* -------------------------------------------------------------------------- */
	/* extract mask bits out of data and pack them into the result */
	u32 ir_extract_bits(u32 data, u32 mask)
	{
	u32 vbit = 1, value = 0;

	do {
	if (mask&1) {
	if (data&1)
	value \|= vbit;
	vbit<<=1;
	}
	data>>=1;
	} while (mask>>=1);

	return value;
	}
	EXPORT_SYMBOL_GPL(ir_extract_bits);

	static int inline getbit(u32 *samples, int bit)
	{
	return (samples[bit/32] & (1 << (31-(bit%32)))) ? 1 : 0;
	}

	/* sump raw samples for visual debugging ;) */
	int ir_dump_samples(u32 *samples, int count)
	{
	int i, bit, start;

	printk(KERN_DEBUG "ir samples: ");
	start = 0;
	for (i = 0; i < count * 32; i++) {
	bit = getbit(samples,i);
	if (bit)
	start = 1;
	if (0 == start)
	continue;
	printk("%s", bit ? "#" : "_");
	}
	printk("\n");
	return 0;
	}
	EXPORT_SYMBOL_GPL(ir_dump_samples);

	/* decode raw samples, pulse distance coding used by NEC remotes */
	int ir_decode_pulsedistance(u32 *samples, int count, int low, int high)
	{
	int i,last,bit,len;
	u32 curBit;
	u32 value;

	/* find start burst */
	for (i = len = 0; i < count * 32; i++) {
	bit = getbit(samples,i);
	if (bit) {
	len++;
	} else {
	if (len >= 29)
	break;
	len = 0;
	}
	}

	/* start burst to short */
	if (len < 29)
	return 0xffffffff;

	/* find start silence */
	for (len = 0; i < count * 32; i++) {
	bit = getbit(samples,i);
	if (bit) {
	break;
	} else {
	len++;
	}
	}

	/* silence to short */
	if (len < 7)
	return 0xffffffff;

	/* go decoding */
	len = 0;
	last = 1;
	value = 0; curBit = 1;
	for (; i < count * 32; i++) {
	bit = getbit(samples,i);
	if (last) {
	if(bit) {
	continue;
	} else {
	len = 1;
	}
	} else {
	if (bit) {
	if (len > (low + high) /2)
	value \|= curBit;
	curBit <<= 1;
	if (curBit == 1)
	break;
	} else {
	len++;
	}
	}
	last = bit;
	}

	return value;
	}
	EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);

	/* decode raw samples, biphase coding, used by rc5 for example */
	int ir_decode_biphase(u32 *samples, int count, int low, int high)
	{
	int i,last,bit,len,flips;
	u32 value;

	/* find start bit (1) */
	for (i = 0; i < 32; i++) {
	bit = getbit(samples,i);
	if (bit)
	break;
	}

	/* go decoding */
	len = 0;
	flips = 0;
	value = 1;
	for (; i < count * 32; i++) {
	if (len > high)
	break;
	if (flips > 1)
	break;
	last = bit;
	bit = getbit(samples,i);
	if (last == bit) {
	len++;
	continue;
	}
	if (len < low) {
	len++;
	flips++;
	continue;
	}
	value <<= 1;
	value \|= bit;
	flips = 0;
	len = 1;
	}
	return value;
	}
	EXPORT_SYMBOL_GPL(ir_decode_biphase);

	/* RC5 decoding stuff, moved from bttv-input.c to share it with
	* saa7134 */

	/* decode raw bit pattern to RC5 code */
	u32 ir_rc5_decode(unsigned int code)
	{
	unsigned int org_code = code;
	unsigned int pair;
	unsigned int rc5 = 0;
	int i;

	for (i = 0; i < 14; ++i) {
	pair = code & 0x3;
	code >>= 2;

	rc5 <<= 1;
	switch (pair) {
	case 0:
	case 2:
	break;
	case 1:
	rc5 \|= 1;
	break;
	case 3:
	IR_dprintk(1, "ir-common: ir_rc5_decode(%x) bad code\n", org_code);
	return 0;
	}
	}
	IR_dprintk(1, "ir-common: code=%x, rc5=%x, start=%x, toggle=%x, address=%x, "
	"instr=%x\n", rc5, org_code, RC5_START(rc5),
	RC5_TOGGLE(rc5), RC5_ADDR(rc5), RC5_INSTR(rc5));
	return rc5;
	}
	EXPORT_SYMBOL_GPL(ir_rc5_decode);

	void ir_rc5_timer_end(unsigned long data)
	{
	struct card_ir ir = (struct card_ir )data;
	struct timeval tv;
	unsigned long current_jiffies, timeout;
	u32 gap;
	u32 rc5 = 0;

	/* get time */
	current_jiffies = jiffies;
	do_gettimeofday(&tv);

	/* avoid overflow with gap >1s */
	if (tv.tv_sec - ir->base_time.tv_sec > 1) {
	gap = 200000;
	} else {
	gap = 1000000 * (tv.tv_sec - ir->base_time.tv_sec) +
	tv.tv_usec - ir->base_time.tv_usec;
	}

	/* signal we're ready to start a new code */
	ir->active = 0;

	/* Allow some timer jitter (RC5 is ~24ms anyway so this is ok) */
	if (gap < 28000) {
	IR_dprintk(1, "ir-common: spurious timer_end\n");
	return;
	}

	if (ir->last_bit < 20) {
	/* ignore spurious codes (caused by light/other remotes) */
	IR_dprintk(1, "ir-common: short code: %x\n", ir->code);
	} else {
	ir->code = (ir->code << ir->shift_by) \| 1;
	rc5 = ir_rc5_decode(ir->code);

	/* two start bits? */
	if (RC5_START(rc5) != ir->start) {
	IR_dprintk(1, "ir-common: rc5 start bits invalid: %u\n", RC5_START(rc5));

	/* right address? */
	} else if (RC5_ADDR(rc5) == ir->addr) {
	u32 toggle = RC5_TOGGLE(rc5);
	u32 instr = RC5_INSTR(rc5);

	/* Good code, decide if repeat/repress */
	if (toggle != RC5_TOGGLE(ir->last_rc5) \|\|
	instr != RC5_INSTR(ir->last_rc5)) {
	IR_dprintk(1, "ir-common: instruction %x, toggle %x\n", instr,
	toggle);
	ir_input_nokey(ir->dev, &ir->ir);
	ir_input_keydown(ir->dev, &ir->ir, instr);
	}

	/* Set/reset key-up timer */
	timeout = current_jiffies +
	msecs_to_jiffies(ir->rc5_key_timeout);
	mod_timer(&ir->timer_keyup, timeout);

	/* Save code for repeat test */
	ir->last_rc5 = rc5;
	}
	}
	}
	EXPORT_SYMBOL_GPL(ir_rc5_timer_end);

	void ir_rc5_timer_keyup(unsigned long data)
	{
	struct card_ir ir = (struct card_ir )data;

	IR_dprintk(1, "ir-common: key released\n");
	ir_input_nokey(ir->dev, &ir->ir);
	}
	EXPORT_SYMBOL_GPL(ir_rc5_timer_keyup);