firmware/drivers/fmradio.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Linus Nielsen Feltzing
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include "lcd.h"
  22 #include "sh7034.h"
  23 #include "kernel.h"
  24 #include "thread.h"
  25 #include "debug.h"
  26 #include "system.h"
  27 #include "fmradio.h"
  28
  29 #if CONFIG_TUNER
  30
  31 /* Signals:
  32    DI (Data In)     - PB0 (doubles as data pin for the LCD)
  33    CL (Clock)       - PB1 (doubles as clock for the LCD)
  34    CE (Chip Enable) - PB3 (also chip select for the LCD, but active low)
  35    DO (Data Out)    - PB4
  36 */
  37
  38 /* cute little functions */
  39 #define CE_LO  and_b(~0x08, PBDRL_ADDR)
  40 #define CE_HI  or_b(0x08, PBDRL_ADDR)
  41 #define CL_LO  and_b(~0x02, PBDRL_ADDR)
  42 #define CL_HI  or_b(0x02, PBDRL_ADDR)
  43 #define DO     (PBDR & 0x10)
  44 #define DI_LO  and_b(~0x01, PBDRL_ADDR)
  45 #define DI_HI  or_b(0x01, PBDRL_ADDR)
  46
  47 #define START or_b((0x08 | 0x02), PBDRL_ADDR)
  48
  49 /* delay loop */
  50 #define DELAY   do { int _x; for(_x=0;_x<10;_x++);} while (0)
  51
  52
  53 int fmradio_read(int addr)
  54 {
  55     int i;
  56     int data = 0;
  57
  58     START;
  59
  60     /* First address bit */
  61     CL_LO;
  62     if(addr & 2)
  63         DI_HI;
  64     else
  65         DI_LO;
  66     DELAY;
  67     CL_HI;
  68     DELAY;
  69
  70     /* Second address bit */
  71     CL_LO;
  72     if(addr & 1)
  73         DI_HI;
  74     else
  75         DI_LO;
  76     DELAY;
  77     CL_HI;
  78     DELAY;
  79
  80     for(i = 0; i < 21;i++)
  81     {
  82         CL_LO;
  83         DELAY;
  84         data <<= 1;
  85         data |= (DO)?1:0;
  86         CL_HI;
  87         DELAY;
  88     }
  89
  90     CE_LO;
  91
  92     return data;
  93 }
  94
  95 void fmradio_set(int addr, int data)
  96 {
  97     int i;
  98
  99     /* Include the address in the data */
 100     data |= addr << 21;
 101
 102     START;
 103
 104     for(i = 0; i < 23;i++)
 105     {
 106         CL_LO;
 107         DELAY;
 108         if(data & (1 << 22))
 109             DI_HI;
 110         else
 111             DI_LO;
 112
 113         data <<= 1;
 114         CL_HI;
 115         DELAY;
 116     }
 117
 118     CE_LO;
 119 }
 120
 121 #endif