LXR linux/drivers/media/rc/img-ir/img-ir-rc5.c

   1/*
   2 * ImgTec IR Decoder setup for Philips RC-5 protocol.
   3 *
   4 * Copyright 2012-2014 Imagination Technologies Ltd.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by the
   8 * Free Software Foundation; either version 2 of the License, or (at your
   9 * option) any later version.
  10 */
  11
  12#include "img-ir-hw.h"
  13
  14/* Convert RC5 data to a scancode */
  15static int img_ir_rc5_scancode(int len, u64 raw, u64 enabled_protocols,
  16                                struct img_ir_scancode_req *request)
  17{
  18        unsigned int addr, cmd, tgl, start;
  19
  20        /* Quirk in the decoder shifts everything by 2 to the left. */
  21        raw   >>= 2;
  22
  23        start   =  (raw >> 13)  & 0x01;
  24        tgl     =  (raw >> 11)  & 0x01;
  25        addr    =  (raw >>  6)  & 0x1f;
  26        cmd     =   raw         & 0x3f;
  27        /*
  28         * 12th bit is used to extend the command in extended RC5 and has
  29         * no effect on standard RC5.
  30         */
  31        cmd     += ((raw >> 12) & 0x01) ? 0 : 0x40;
  32
  33        if (!start)
  34                return -EINVAL;
  35
  36        request->protocol = RC_TYPE_RC5;
  37        request->scancode = addr << 8 | cmd;
  38        request->toggle   = tgl;
  39        return IMG_IR_SCANCODE;
  40}
  41
  42/* Convert RC5 scancode to RC5 data filter */
  43static int img_ir_rc5_filter(const struct rc_scancode_filter *in,
  44                                 struct img_ir_filter *out, u64 protocols)
  45{
  46        /* Not supported by the hw. */
  47        return -EINVAL;
  48}
  49
  50/*
  51 * RC-5 decoder
  52 * see http://www.sbprojects.com/knowledge/ir/rc5.php
  53 */
  54struct img_ir_decoder img_ir_rc5 = {
  55        .type      = RC_BIT_RC5,
  56        .control   = {
  57                .bitoriend2     = 1,
  58                .code_type      = IMG_IR_CODETYPE_BIPHASE,
  59                .decodend2      = 1,
  60        },
  61        /* main timings */
  62        .tolerance      = 16,
  63        .unit           = 888888, /* 1/36k*32=888.888microseconds */
  64        .timings        = {
  65                /* 10 symbol */
  66                .s10 = {
  67                        .pulse  = { 1 },
  68                        .space  = { 1 },
  69                },
  70
  71                /* 11 symbol */
  72                .s11 = {
  73                        .pulse  = { 1 },
  74                        .space  = { 1 },
  75                },
  76
  77                /* free time */
  78                .ft  = {
  79                        .minlen = 14,
  80                        .maxlen = 14,
  81                        .ft_min = 5,
  82                },
  83        },
  84
  85        /* scancode logic */
  86        .scancode       = img_ir_rc5_scancode,
  87        .filter         = img_ir_rc5_filter,
  88};
  89