drivers/media/rc/img-ir/img-ir-sharp.c

   1 /*
   2  * ImgTec IR Decoder setup for Sharp 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 Sharp data to a scancode */
  15 static int img_ir_sharp_scancode(int len, u64 raw, u64 enabled_protocols,
  16                                  struct img_ir_scancode_req *request)
  17 {
  18         unsigned int addr, cmd, exp, chk;
  19
  20         if (len != 15)
  21                 return -EINVAL;
  22
  23         addr = (raw >>   0) & 0x1f;
  24         cmd  = (raw >>   5) & 0xff;
  25         exp  = (raw >>  13) &  0x1;
  26         chk  = (raw >>  14) &  0x1;
  27
  28         /* validate data */
  29         if (!exp)
  30                 return -EINVAL;
  31         if (chk)
  32                 /* probably the second half of the message */
  33                 return -EINVAL;
  34
  35         request->protocol = RC_TYPE_SHARP;
  36         request->scancode = addr << 8 | cmd;
  37         return IMG_IR_SCANCODE;
  38 }
  39
  40 /* Convert Sharp scancode to Sharp data filter */
  41 static int img_ir_sharp_filter(const struct rc_scancode_filter *in,
  42                                struct img_ir_filter *out, u64 protocols)
  43 {
  44         unsigned int addr, cmd, exp = 0, chk = 0;
  45         unsigned int addr_m, cmd_m, exp_m = 0, chk_m = 0;
  46
  47         addr   = (in->data >> 8) & 0x1f;
  48         addr_m = (in->mask >> 8) & 0x1f;
  49         cmd    = (in->data >> 0) & 0xff;
  50         cmd_m  = (in->mask >> 0) & 0xff;
  51         if (cmd_m) {
  52                 /* if filtering commands, we can only match the first part */
  53                 exp   = 1;
  54                 exp_m = 1;
  55                 chk   = 0;
  56                 chk_m = 1;
  57         }
  58
  59         out->data = addr        |
  60                     cmd   <<  5 |
  61                     exp   << 13 |
  62                     chk   << 14;
  63         out->mask = addr_m      |
  64                     cmd_m <<  5 |
  65                     exp_m << 13 |
  66                     chk_m << 14;
  67
  68         return 0;
  69 }
  70
  71 /*
  72  * Sharp decoder
  73  * See also http://www.sbprojects.com/knowledge/ir/sharp.php
  74  */
  75 struct img_ir_decoder img_ir_sharp = {
  76         .type = RC_BIT_SHARP,
  77         .control = {
  78                 .decoden = 0,
  79                 .decodend2 = 1,
  80                 .code_type = IMG_IR_CODETYPE_PULSEDIST,
  81                 .d1validsel = 1,
  82         },
  83         /* main timings */
  84         .tolerance = 20,        /* 20% */
  85         .timings = {
  86                 /* 0 symbol */
  87                 .s10 = {
  88                         .pulse = { 320  /* 320 us */ },
  89                         .space = { 680  /* 1 ms period */ },
  90                 },
  91                 /* 1 symbol */
  92                 .s11 = {
  93                         .pulse = { 320  /* 320 us */ },
  94                         .space = { 1680 /* 2 ms period */ },
  95                 },
  96                 /* free time */
  97                 .ft = {
  98                         .minlen = 15,
  99                         .maxlen = 15,
 100                         .ft_min = 5000, /* 5 ms */
 101                 },
 102         },
 103         /* scancode logic */
 104         .scancode = img_ir_sharp_scancode,
 105         .filter = img_ir_sharp_filter,
 106 };