firmware/target/arm/as3525/fmradio-i2c-as3525.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2008 by Bertrik Sikken
  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
  22 /*
  23     This is the fmradio_i2c interface, used by the radio driver
  24     to communicate with the radio tuner chip.
  25
  26     It is implemented using the generic i2c driver, which does "bit-banged"
  27     I2C with a couple of GPIO pins.
  28  */
  29
  30 #include "as3525.h"
  31 #include "generic_i2c.h"
  32 #include "fmradio_i2c.h"
  33
  34 #if     defined(SANSA_CLIP) || defined(SANSA_C200V2)
  35 #define I2C_SCL_GPIO(x) GPIOB_PIN(x)
  36 #define I2C_SDA_GPIO(x) GPIOB_PIN(x)
  37 #define I2C_SCL_GPIO_DIR GPIOB_DIR
  38 #define I2C_SDA_GPIO_DIR GPIOB_DIR
  39 #define I2C_SCL_PIN 4
  40 #define I2C_SDA_PIN 5
  41
  42 #elif     defined(SANSA_CLIPV2) || defined(SANSA_CLIPPLUS)
  43 #define I2C_SCL_GPIO(x) GPIOB_PIN(x)
  44 #define I2C_SDA_GPIO(x) GPIOB_PIN(x)
  45 #define I2C_SCL_GPIO_DIR GPIOB_DIR
  46 #define I2C_SDA_GPIO_DIR GPIOB_DIR
  47 #define I2C_SCL_PIN 6
  48 #define I2C_SDA_PIN 7
  49
  50 #elif   defined(SANSA_M200V4)
  51 #define I2C_SCL_GPIO(x) GPIOD_PIN(x)
  52 #define I2C_SDA_GPIO(x) GPIOD_PIN(x)
  53 #define I2C_SCL_GPIO_DIR GPIOD_DIR
  54 #define I2C_SDA_GPIO_DIR GPIOD_DIR
  55 #define I2C_SCL_PIN 7
  56 #define I2C_SDA_PIN 6
  57
  58 #elif   defined(SANSA_FUZE) || defined(SANSA_E200V2)
  59 #define I2C_SCL_GPIO(x) GPIOA_PIN(x)
  60 #define I2C_SDA_GPIO(x) GPIOA_PIN(x)
  61 #define I2C_SCL_GPIO_DIR GPIOA_DIR
  62 #define I2C_SDA_GPIO_DIR GPIOA_DIR
  63 #define I2C_SCL_PIN 6
  64 #define I2C_SDA_PIN 7
  65
  66 #elif   defined(SANSA_FUZEV2)
  67 #define I2C_SCL_GPIO(x) GPIOB_PIN(x)
  68 #define I2C_SDA_GPIO(x) GPIOA_PIN(x)
  69 #define I2C_SCL_GPIO_DIR GPIOB_DIR
  70 #define I2C_SDA_GPIO_DIR GPIOA_DIR
  71 #define I2C_SCL_PIN 1
  72 #define I2C_SDA_PIN 0
  73
  74 #else
  75 #error no FM I2C GPIOPIN defines
  76 #endif
  77
  78 static int fm_i2c_bus;
  79
  80 static void fm_scl_hi(void)
  81 {
  82     I2C_SCL_GPIO(I2C_SCL_PIN) = 1 << I2C_SCL_PIN;
  83 }
  84
  85 static void fm_scl_lo(void)
  86 {
  87     I2C_SCL_GPIO(I2C_SCL_PIN) = 0;
  88 }
  89
  90 static void fm_sda_hi(void)
  91 {
  92     I2C_SDA_GPIO(I2C_SDA_PIN) = 1 << I2C_SDA_PIN;
  93 }
  94
  95 static void fm_sda_lo(void)
  96 {
  97     I2C_SDA_GPIO(I2C_SDA_PIN) = 0;
  98 }
  99
 100 static void fm_sda_input(void)
 101 {
 102     I2C_SDA_GPIO_DIR &= ~(1 << I2C_SDA_PIN);
 103 }
 104
 105 static void fm_sda_output(void)
 106 {
 107     I2C_SDA_GPIO_DIR |= 1 << I2C_SDA_PIN;
 108 }
 109
 110 static void fm_scl_input(void)
 111 {
 112     I2C_SCL_GPIO_DIR &= ~(1 << I2C_SCL_PIN);
 113 }
 114
 115 static void fm_scl_output(void)
 116 {
 117     I2C_SCL_GPIO_DIR |= 1 << I2C_SCL_PIN;
 118 }
 119
 120 static int fm_sda(void)
 121 {
 122     return I2C_SDA_GPIO(I2C_SDA_PIN);
 123 }
 124
 125 static int fm_scl(void)
 126 {
 127     return I2C_SCL_GPIO(I2C_SCL_PIN);
 128 }
 129
 130 /* simple and crude delay, used for all delays in the generic i2c driver */
 131 static void fm_delay(void)
 132 {
 133     volatile int i;
 134
 135     /* this loop is uncalibrated and could use more sophistication */
 136     for (i = 0; i < 20; i++) {
 137     }
 138 }
 139
 140 /* interface towards the generic i2c driver */
 141 static const struct i2c_interface fm_i2c_interface = {
 142     .scl_hi = fm_scl_hi,
 143     .scl_lo = fm_scl_lo,
 144     .sda_hi = fm_sda_hi,
 145     .sda_lo = fm_sda_lo,
 146     .sda_input = fm_sda_input,
 147     .sda_output = fm_sda_output,
 148     .scl_input = fm_scl_input,
 149     .scl_output = fm_scl_output,
 150     .scl = fm_scl,
 151     .sda = fm_sda,
 152
 153     .delay_hd_sta = fm_delay,
 154     .delay_hd_dat = fm_delay,
 155     .delay_su_dat = fm_delay,
 156     .delay_su_sto = fm_delay,
 157     .delay_su_sta = fm_delay,
 158     .delay_thigh = fm_delay
 159 };
 160
 161 /* initialise i2c for fmradio */
 162 void fmradio_i2c_init(void)
 163 {
 164     fm_i2c_bus = i2c_add_node(&fm_i2c_interface);
 165 }
 166
 167 int fmradio_i2c_write(unsigned char address, const unsigned char* buf, int count)
 168 {
 169 #ifdef SANSA_FUZEV2
 170     CCU_IO &= ~(1<<12);
 171 #endif
 172     int ret = i2c_write_data(fm_i2c_bus, address, -1, buf, count);
 173 #ifdef SANSA_FUZEV2
 174     CCU_IO |= 1<<12;
 175 #endif
 176     return ret;
 177 }
 178
 179 int fmradio_i2c_read(unsigned char address, unsigned char* buf, int count)
 180 {
 181 #ifdef SANSA_FUZEV2
 182     CCU_IO &= ~(1<<12);
 183 #endif
 184     int ret = i2c_read_data(fm_i2c_bus, address, -1, buf, count);
 185 #ifdef SANSA_FUZEV2
 186     CCU_IO |= 1<<12;
 187 #endif
 188     return ret;
 189 }