diff options
Diffstat (limited to 'drivers/media/common/ir-functions.c')
| -rw-r--r-- | drivers/media/common/ir-functions.c | 272 |
1 files changed, 272 insertions, 0 deletions
diff --git a/drivers/media/common/ir-functions.c b/drivers/media/common/ir-functions.c new file mode 100644 index 000000000000..397cff8b345b --- /dev/null +++ b/drivers/media/common/ir-functions.c @@ -0,0 +1,272 @@ +/* + * + * 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: + */ + |