/*
*
* 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/moduleparam.h>
#include <linux/string.h>
#include <media/ir-common.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 int debug = 0; /* debug level (0,1,2) */
module_param(debug, int, 0644);
#define dprintk(level, fmt, arg...) if (debug >= level) \
printk(KERN_DEBUG fmt , ## arg)
/* -------------------------------------------------------------------------- */
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 raw=0x%02x down=%d\n",
dev->name,ir->ir_key,ir->ir_raw,ir->keypressed);
return;
}
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);
}
/* -------------------------------------------------------------------------- */
void ir_input_init(struct input_dev *dev, struct ir_input_state *ir,
int ir_type, IR_KEYTAB_TYPE *ir_codes)
{
int i;
ir->ir_type = ir_type;
if (ir_codes)
memcpy(ir->ir_codes, ir_codes, sizeof(ir->ir_codes));
dev->keycode = ir->ir_codes;
dev->keycodesize = sizeof(IR_KEYTAB_TYPE);
dev->keycodemax = IR_KEYTAB_SIZE;
for (i = 0; i < IR_KEYTAB_SIZE; i++)
set_bit(ir->ir_codes[i], dev->keybit);
clear_bit(0, dev->keybit);
set_bit(EV_KEY, dev->evbit);
if (repeat)
set_bit(EV_REP, dev->evbit);
}
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);
}
}
void ir_input_keydown(struct input_dev *dev, struct ir_input_state *ir,
u32 ir_key, u32 ir_raw)
{
u32 keycode = IR_KEYCODE(ir->ir_codes, 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->ir_raw = ir_raw;
ir->keycode = keycode;
ir->keypressed = 1;
ir_input_key_event(dev,ir);
}
}
/* -------------------------------------------------------------------------- */
u32 ir_extract_bits(u32 data, u32 mask)
{
int mbit, vbit;
u32 value;
value = 0;
vbit = 0;
for (mbit = 0; mbit < 32; mbit++) {
if (!(mask & ((u32)1 << mbit)))
continue;
if (data & ((u32)1 << mbit))
value |= (1 << vbit);
vbit++;
}
return value;
}
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;
}
/* 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;
}
/* 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_input_init);
EXPORT_SYMBOL_GPL(ir_input_nokey);
EXPORT_SYMBOL_GPL(ir_input_keydown);
EXPORT_SYMBOL_GPL(ir_extract_bits);
EXPORT_SYMBOL_GPL(ir_dump_samples);
EXPORT_SYMBOL_GPL(ir_decode_biphase);
EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);
/*
* Local variables:
* c-basic-offset: 8
* End:
*/
