firmware/target/arm/s5l8700/fmradio-i2c-meizu.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2009 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     FM radio i2c interface, allows the radio driver to talk to the tuner chip.
  24
  25     It is implemented using the generic i2c driver, which does "bit-banged"
  26     I2C with a couple of GPIO pins.
  27  */
  28
  29 #include "config.h"
  30
  31 #include "inttypes.h"
  32 #include "s5l8700.h"
  33 #include "generic_i2c.h"
  34 #include "fmradio_i2c.h"
  35
  36 #define I2C_GPIO        PDAT3
  37 #define I2C_GPIO_DIR    PCON3
  38 #define I2C_SCL_PIN     4
  39 #define I2C_SDA_PIN     2
  40
  41 #define SCL_DIR_MASK    (0xF<<(4*I2C_SCL_PIN))
  42 #define SCL_DIR_OUT     (1<<(4*I2C_SCL_PIN))
  43 #define SCL_DIR_IN      0
  44 #define SDA_DIR_MASK    (0xF<<(4*I2C_SDA_PIN))
  45 #define SDA_DIR_OUT     (1<<(4*I2C_SDA_PIN))
  46 #define SDA_DIR_IN      0
  47
  48 static int fm_i2c_bus;
  49
  50 static void fm_scl_hi(void)
  51 {
  52     I2C_GPIO |= 1 << I2C_SCL_PIN;
  53 }
  54
  55 static void fm_scl_lo(void)
  56 {
  57     I2C_GPIO &= ~(1 << I2C_SCL_PIN);
  58 }
  59
  60 static void fm_sda_hi(void)
  61 {
  62     I2C_GPIO |= 1 << I2C_SDA_PIN;
  63 }
  64
  65 static void fm_sda_lo(void)
  66 {
  67     I2C_GPIO &= ~(1 << I2C_SDA_PIN);
  68 }
  69
  70 static void fm_sda_input(void)
  71 {
  72     I2C_GPIO_DIR = (I2C_GPIO_DIR & ~SDA_DIR_MASK) | SDA_DIR_IN;
  73 }
  74
  75 static void fm_sda_output(void)
  76 {
  77     I2C_GPIO_DIR = (I2C_GPIO_DIR & ~SDA_DIR_MASK) | SDA_DIR_OUT;
  78 }
  79
  80 static void fm_scl_input(void)
  81 {
  82     I2C_GPIO_DIR = (I2C_GPIO_DIR & ~SCL_DIR_MASK) | SCL_DIR_IN;
  83 }
  84
  85 static void fm_scl_output(void)
  86 {
  87     I2C_GPIO_DIR = (I2C_GPIO_DIR & ~SCL_DIR_MASK) | SCL_DIR_OUT;
  88 }
  89
  90 static int fm_sda(void)
  91 {
  92     return (I2C_GPIO & (1 << I2C_SDA_PIN));
  93 }
  94
  95 static int fm_scl(void)
  96 {
  97     return (I2C_GPIO & (1 << I2C_SCL_PIN));
  98 }
  99
 100 /* simple and crude delay, used for all delays in the generic i2c driver */
 101 static void fm_delay(void)
 102 {
 103     volatile int i;
 104
 105     /* this loop is uncalibrated and could use more sophistication */
 106     for (i = 0; i < 20; i++) {
 107     }
 108 }
 109
 110 /* interface towards the generic i2c driver */
 111 static const struct i2c_interface fm_i2c_interface = {
 112     .scl_hi = fm_scl_hi,
 113     .scl_lo = fm_scl_lo,
 114     .sda_hi = fm_sda_hi,
 115     .sda_lo = fm_sda_lo,
 116     .sda_input = fm_sda_input,
 117     .sda_output = fm_sda_output,
 118     .scl_input = fm_scl_input,
 119     .scl_output = fm_scl_output,
 120     .scl = fm_scl,
 121     .sda = fm_sda,
 122
 123     .delay_hd_sta = fm_delay,
 124     .delay_hd_dat = fm_delay,
 125     .delay_su_dat = fm_delay,
 126     .delay_su_sto = fm_delay,
 127     .delay_su_sta = fm_delay,
 128     .delay_thigh = fm_delay
 129 };
 130
 131 /* initialise i2c for fmradio */
 132 void fmradio_i2c_init(void)
 133 {
 134     fm_i2c_bus = i2c_add_node(&fm_i2c_interface);
 135 }
 136
 137 int fmradio_i2c_write(unsigned char address, const unsigned char* buf, int count)
 138 {
 139     return i2c_write_data(fm_i2c_bus, address, -1, buf, count);
 140 }
 141
 142 int fmradio_i2c_read(unsigned char address, unsigned char* buf, int count)
 143 {
 144     return i2c_read_data(fm_i2c_bus, address, -1, buf, count);
 145 }
 146