unleashed-firmware/lib/irda/encoder_decoder/common/irda_common_decoder.c
Albert Kharisov 98830a8a41
[FL-1956] Fix long packets bug, fix Manchester overrun (#766)
Also fix RC6 test to detect this manchester bug
2021-10-16 15:00:21 +03:00

316 lines
11 KiB
C

#include "furi/check.h"
#include "furi/common_defines.h"
#include "irda.h"
#include "irda_common_i.h"
#include <stdbool.h>
#include <furi.h>
#include "irda_i.h"
#include <stdint.h>
static void irda_common_decoder_reset_state(IrdaCommonDecoder* decoder);
static inline size_t consume_samples(uint32_t* array, size_t len, size_t shift) {
furi_assert(len >= shift);
len -= shift;
for (int i = 0; i < len; ++i)
array[i] = array[i + shift];
return len;
}
static inline void accumulate_lsb(IrdaCommonDecoder* decoder, bool bit) {
uint16_t index = decoder->databit_cnt / 8;
uint8_t shift = decoder->databit_cnt % 8; // LSB first
if (!shift)
decoder->data[index] = 0;
if (bit) {
decoder->data[index] |= (0x1 << shift); // add 1
} else {
(void) decoder->data[index]; // add 0
}
++decoder->databit_cnt;
}
static bool irda_check_preamble(IrdaCommonDecoder* decoder) {
furi_assert(decoder);
bool result = false;
bool start_level = (decoder->level + decoder->timings_cnt + 1) % 2;
if (decoder->timings_cnt == 0)
return false;
// align to start at Mark timing
if (!start_level) {
decoder->timings_cnt = consume_samples(decoder->timings, decoder->timings_cnt, 1);
}
if (decoder->protocol->timings.preamble_mark == 0) {
return true;
}
while ((!result) && (decoder->timings_cnt >= 2)) {
float preamble_tolerance = decoder->protocol->timings.preamble_tolerance;
uint16_t preamble_mark = decoder->protocol->timings.preamble_mark;
uint16_t preamble_space = decoder->protocol->timings.preamble_space;
if ((MATCH_TIMING(decoder->timings[0], preamble_mark, preamble_tolerance))
&& (MATCH_TIMING(decoder->timings[1], preamble_space, preamble_tolerance))) {
result = true;
}
decoder->timings_cnt = consume_samples(decoder->timings, decoder->timings_cnt, 2);
}
return result;
}
/**
* decoder->protocol->databit_len[0] contains biggest amount of bits, for this protocol.
* decoder->protocol->databit_len[1...] contains lesser values, but which can be decoded
* for some protocol modifications.
*/
static IrdaStatus irda_common_decode_bits(IrdaCommonDecoder* decoder) {
furi_assert(decoder);
IrdaStatus status = IrdaStatusOk;
const IrdaTimings* timings = &decoder->protocol->timings;
while (decoder->timings_cnt && (status == IrdaStatusOk)) {
bool level = (decoder->level + decoder->timings_cnt + 1) % 2;
uint32_t timing = decoder->timings[0];
if (timings->min_split_time && !level) {
if (timing > timings->min_split_time) {
/* long low timing - check if we're ready for any of protocol modification */
for (int i = 0; decoder->protocol->databit_len[i] && (i < COUNT_OF(decoder->protocol->databit_len)); ++i) {
if (decoder->protocol->databit_len[i] == decoder->databit_cnt) {
return IrdaStatusReady;
}
}
} else if (decoder->protocol->databit_len[0] == decoder->databit_cnt) {
/* short low timing for longest protocol - this is signal is longer than we expected */
return IrdaStatusError;
}
}
status = decoder->protocol->decode(decoder, level, timing);
furi_check(decoder->databit_cnt <= decoder->protocol->databit_len[0]);
furi_assert(status == IrdaStatusError || status == IrdaStatusOk);
if (status == IrdaStatusError) {
break;
}
decoder->timings_cnt = consume_samples(decoder->timings, decoder->timings_cnt, 1);
/* check if largest protocol version can be decoded */
if (level && (decoder->protocol->databit_len[0] == decoder->databit_cnt) && !timings->min_split_time) {
status = IrdaStatusReady;
break;
}
}
return status;
}
/* Pulse Distance-Width Modulation */
IrdaStatus irda_common_decode_pdwm(IrdaCommonDecoder* decoder, bool level, uint32_t timing) {
furi_assert(decoder);
IrdaStatus status = IrdaStatusOk;
uint32_t bit_tolerance = decoder->protocol->timings.bit_tolerance;
uint16_t bit1_mark = decoder->protocol->timings.bit1_mark;
uint16_t bit1_space = decoder->protocol->timings.bit1_space;
uint16_t bit0_mark = decoder->protocol->timings.bit0_mark;
uint16_t bit0_space = decoder->protocol->timings.bit0_space;
bool analyze_timing = level ^ (bit1_mark == bit0_mark);
uint16_t bit1 = level ? bit1_mark : bit1_space;
uint16_t bit0 = level ? bit0_mark : bit0_space;
uint16_t no_info_timing = (bit1_mark == bit0_mark) ? bit1_mark : bit1_space;
if (analyze_timing) {
if (MATCH_TIMING(timing, bit1, bit_tolerance)) {
accumulate_lsb(decoder, 1);
} else if (MATCH_TIMING(timing, bit0, bit_tolerance)) {
accumulate_lsb(decoder, 0);
} else {
status = IrdaStatusError;
}
} else {
if (!MATCH_TIMING(timing, no_info_timing, bit_tolerance)) {
status = IrdaStatusError;
}
}
return status;
}
/* level switch detection goes in middle of time-quant */
IrdaStatus irda_common_decode_manchester(IrdaCommonDecoder* decoder, bool level, uint32_t timing) {
furi_assert(decoder);
uint16_t bit = decoder->protocol->timings.bit1_mark;
uint16_t tolerance = decoder->protocol->timings.bit_tolerance;
bool* switch_detect = &decoder->switch_detect;
furi_assert((*switch_detect == true) || (*switch_detect == false));
bool single_timing = MATCH_TIMING(timing, bit, tolerance);
bool double_timing = MATCH_TIMING(timing, 2*bit, tolerance);
if(!single_timing && !double_timing) {
return IrdaStatusError;
}
if (decoder->protocol->manchester_start_from_space && (decoder->databit_cnt == 0)) {
*switch_detect = 1; /* fake as we were previously in the middle of time-quant */
accumulate_lsb(decoder, 0);
}
if (*switch_detect == 0) {
if (double_timing) {
return IrdaStatusError;
}
/* only single timing - level switch required in the middle of time-quant */
*switch_detect = 1;
} else {
/* double timing means we're in the middle of time-quant again */
if (single_timing)
*switch_detect = 0;
}
if (*switch_detect) {
if (decoder->protocol->databit_len[0] == decoder->databit_cnt) {
return IrdaStatusError;
}
accumulate_lsb(decoder, level);
}
return IrdaStatusOk;
}
IrdaMessage* irda_common_decoder_check_ready(IrdaCommonDecoder* decoder) {
IrdaMessage* message = NULL;
bool found_length = false;
for (int i = 0; decoder->protocol->databit_len[i] && (i < COUNT_OF(decoder->protocol->databit_len)); ++i) {
if (decoder->protocol->databit_len[i] == decoder->databit_cnt) {
found_length = true;
break;
}
}
if (found_length && decoder->protocol->interpret(decoder)) {
decoder->databit_cnt = 0;
message = &decoder->message;
if (decoder->protocol->decode_repeat) {
decoder->state = IrdaCommonDecoderStateProcessRepeat;
} else {
decoder->state = IrdaCommonDecoderStateWaitPreamble;
}
}
return message;
}
IrdaMessage* irda_common_decode(IrdaCommonDecoder* decoder, bool level, uint32_t duration) {
furi_assert(decoder);
IrdaMessage* message = 0;
IrdaStatus status = IrdaStatusError;
if (decoder->level == level) {
irda_common_decoder_reset(decoder);
}
decoder->level = level; // start with low level (Space timing)
decoder->timings[decoder->timings_cnt] = duration;
decoder->timings_cnt++;
furi_check(decoder->timings_cnt <= sizeof(decoder->timings));
while(1) {
switch (decoder->state) {
case IrdaCommonDecoderStateWaitPreamble:
if (irda_check_preamble(decoder)) {
decoder->state = IrdaCommonDecoderStateDecode;
decoder->databit_cnt = 0;
decoder->switch_detect = false;
continue;
}
break;
case IrdaCommonDecoderStateDecode:
status = irda_common_decode_bits(decoder);
if (status == IrdaStatusReady) {
message = irda_common_decoder_check_ready(decoder);
if (message) {
continue;
} else if (decoder->protocol->databit_len[0] == decoder->databit_cnt) {
/* error: can't decode largest protocol - begin decoding from start */
decoder->state = IrdaCommonDecoderStateWaitPreamble;
}
} else if (status == IrdaStatusError) {
irda_common_decoder_reset_state(decoder);
continue;
}
break;
case IrdaCommonDecoderStateProcessRepeat:
status = decoder->protocol->decode_repeat(decoder);
if (status == IrdaStatusError) {
irda_common_decoder_reset_state(decoder);
continue;
} else if (status == IrdaStatusReady) {
decoder->message.repeat = true;
message = &decoder->message;
}
break;
}
break;
}
return message;
}
void* irda_common_decoder_alloc(const IrdaCommonProtocolSpec* protocol) {
furi_assert(protocol);
/* protocol->databit_len[0] has to contain biggest value of bits that can be decoded */
for (int i = 1; i < COUNT_OF(protocol->databit_len); ++i) {
furi_assert(protocol->databit_len[i] <= protocol->databit_len[0]);
}
uint32_t alloc_size = sizeof(IrdaCommonDecoder)
+ protocol->databit_len[0] / 8
+ !!(protocol->databit_len[0] % 8);
IrdaCommonDecoder* decoder = furi_alloc(alloc_size);
decoder->protocol = protocol;
decoder->level = true;
return decoder;
}
void irda_common_decoder_free(IrdaCommonDecoder* decoder) {
furi_assert(decoder);
free(decoder);
}
void irda_common_decoder_reset_state(IrdaCommonDecoder* decoder) {
decoder->state = IrdaCommonDecoderStateWaitPreamble;
decoder->databit_cnt = 0;
decoder->switch_detect = false;
decoder->message.protocol = IrdaProtocolUnknown;
if (decoder->protocol->timings.preamble_mark == 0) {
if (decoder->timings_cnt > 0) {
decoder->timings_cnt = consume_samples(decoder->timings, decoder->timings_cnt, 1);
}
}
}
void irda_common_decoder_reset(IrdaCommonDecoder* decoder) {
furi_assert(decoder);
irda_common_decoder_reset_state(decoder);
decoder->timings_cnt = 0;
}