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

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * ImgTec IR Decoder setup for Philips RC-5 protocol.
   4 *
   5 * Copyright 2012-2014 Imagination Technologies Ltd.
   6 */
   7
   8#include "img-ir-hw.h"
   9
  10/* Convert RC5 data to a scancode */
  11static int img_ir_rc5_scancode(int len, u64 raw, u64 enabled_protocols,
  12                                struct img_ir_scancode_req *request)
  13{
  14        unsigned int addr, cmd, tgl, start;
  15
  16        /* Quirk in the decoder shifts everything by 2 to the left. */
  17        raw   >>= 2;
  18
  19        start   =  (raw >> 13)  & 0x01;
  20        tgl     =  (raw >> 11)  & 0x01;
  21        addr    =  (raw >>  6)  & 0x1f;
  22        cmd     =   raw         & 0x3f;
  23        /*
  24         * 12th bit is used to extend the command in extended RC5 and has
  25         * no effect on standard RC5.
  26         */
  27        cmd     += ((raw >> 12) & 0x01) ? 0 : 0x40;
  28
  29        if (!start)
  30                return -EINVAL;
  31
  32        request->protocol = RC_PROTO_RC5;
  33        request->scancode = addr << 8 | cmd;
  34        request->toggle   = tgl;
  35        return IMG_IR_SCANCODE;
  36}
  37
  38/* Convert RC5 scancode to RC5 data filter */
  39static int img_ir_rc5_filter(const struct rc_scancode_filter *in,
  40                                 struct img_ir_filter *out, u64 protocols)
  41{
  42        /* Not supported by the hw. */
  43        return -EINVAL;
  44}
  45
  46/*
  47 * RC-5 decoder
  48 * see http://www.sbprojects.com/knowledge/ir/rc5.php
  49 */
  50struct img_ir_decoder img_ir_rc5 = {
  51        .type      = RC_PROTO_BIT_RC5,
  52        .control   = {
  53                .bitoriend2     = 1,
  54                .code_type      = IMG_IR_CODETYPE_BIPHASE,
  55                .decodend2      = 1,
  56        },
  57        /* main timings */
  58        .tolerance      = 16,
  59        .unit           = 888888, /* 1/36k*32=888.888microseconds */
  60        .timings        = {
  61                /* 10 symbol */
  62                .s10 = {
  63                        .pulse  = { 1 },
  64                        .space  = { 1 },
  65                },
  66
  67                /* 11 symbol */
  68                .s11 = {
  69                        .pulse  = { 1 },
  70                        .space  = { 1 },
  71                },
  72
  73                /* free time */
  74                .ft  = {
  75                        .minlen = 14,
  76                        .maxlen = 14,
  77                        .ft_min = 5,
  78                },
  79        },
  80
  81        /* scancode logic */
  82        .scancode       = img_ir_rc5_scancode,
  83        .filter         = img_ir_rc5_filter,
  84};
  85