cregit-Linux how code gets into the kernel

Release 4.7 drivers/media/rc/img-ir/img-ir-rc6.c

/*
 * ImgTec IR Decoder setup for Philips RC-6 protocol.
 *
 * Copyright 2012-2014 Imagination Technologies Ltd.
 *
 * 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.
 */

#include "img-ir-hw.h"

/* Convert RC6 data to a scancode */

static int img_ir_rc6_scancode(int len, u64 raw, u64 enabled_protocols, struct img_ir_scancode_req *request) { unsigned int addr, cmd, mode, trl1, trl2; /* * Due to a side effect of the decoder handling the double length * Trailer bit, the header information is a bit scrambled, and the * raw data is shifted incorrectly. * This workaround effectively recovers the header bits. * * The Header field should look like this: * * StartBit ModeBit2 ModeBit1 ModeBit0 TrailerBit * * But what we get is: * * ModeBit2 ModeBit1 ModeBit0 TrailerBit1 TrailerBit2 * * The start bit is not important to recover the scancode. */ raw >>= 27; trl1 = (raw >> 17) & 0x01; trl2 = (raw >> 16) & 0x01; mode = (raw >> 18) & 0x07; addr = (raw >> 8) & 0xff; cmd = raw & 0xff; /* * Due to the above explained irregularity the trailer bits cannot * have the same value. */ if (trl1 == trl2) return -EINVAL; /* Only mode 0 supported for now */ if (mode) return -EINVAL; request->protocol = RC_TYPE_RC6_0; request->scancode = addr << 8 | cmd; request->toggle = trl2; return IMG_IR_SCANCODE; }

Contributors

PersonTokensPropCommitsCommitProp
sifan naeemsifan naeem128100.00%1100.00%
Total128100.00%1100.00%

/* Convert RC6 scancode to RC6 data filter */
static int img_ir_rc6_filter(const struct rc_scancode_filter *in, struct img_ir_filter *out, u64 protocols) { /* Not supported by the hw. */ return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
sifan naeemsifan naeem25100.00%1100.00%
Total25100.00%1100.00%

/* * RC-6 decoder * see http://www.sbprojects.com/knowledge/ir/rc6.php */ struct img_ir_decoder img_ir_rc6 = { .type = RC_BIT_RC6_0, .control = { .bitorien = 1, .code_type = IMG_IR_CODETYPE_BIPHASE, .decoden = 1, .decodinpol = 1, }, /* main timings */ .tolerance = 20, /* * Due to a quirk in the img-ir decoder, default header values do * not work, the values described below were extracted from * successful RTL test cases. */ .timings = { /* leader symbol */ .ldr = { .pulse = { 650 }, .space = { 660 }, }, /* 0 symbol */ .s00 = { .pulse = { 370 }, .space = { 370 }, }, /* 01 symbol */ .s01 = { .pulse = { 370 }, .space = { 370 }, }, /* free time */ .ft = { .minlen = 21, .maxlen = 21, .ft_min = 2666, /* 2.666 ms */ }, }, /* scancode logic */ .scancode = img_ir_rc6_scancode, .filter = img_ir_rc6_filter, };

Overall Contributors

PersonTokensPropCommitsCommitProp
sifan naeemsifan naeem302100.00%1100.00%
Total302100.00%1100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}