LXR uboot/drivers/hwmon/lm63.c

   1/*
   2 * (C) Copyright 2007-2008
   3 * Dirk Eibach,  Guntermann & Drunck GmbH, eibach@gdsys.de
   4 * based on lm75.c by Bill Hunter
   5 *
   6 * SPDX-License-Identifier:     GPL-2.0+
   7 */
   8
   9/*
  10 * National LM63/LM64 Temperature Sensor
  11 * Main difference: LM 64 has -16 Kelvin temperature offset
  12 */
  13
  14#include <common.h>
  15#include <i2c.h>
  16#include <dtt.h>
  17
  18#define DTT_I2C_LM63_ADDR       0x4C    /* National LM63 device */
  19
  20#define DTT_READ_TEMP_RMT_MSB   0x01
  21#define DTT_CONFIG              0x03
  22#define DTT_READ_TEMP_RMT_LSB   0x10
  23#define DTT_TACHLIM_LSB         0x48
  24#define DTT_TACHLIM_MSB         0x49
  25#define DTT_FAN_CONFIG          0x4A
  26#define DTT_PWM_FREQ            0x4D
  27#define DTT_PWM_LOOKUP_BASE     0x50
  28
  29struct pwm_lookup_entry {
  30        u8 temp;
  31        u8 pwm;
  32};
  33
  34/*
  35 * Device code
  36 */
  37
  38int dtt_read(int sensor, int reg)
  39{
  40        int dlen;
  41        uchar data[2];
  42
  43        /*
  44         * Calculate sensor address and register.
  45         */
  46        if (!sensor)
  47                sensor = DTT_I2C_LM63_ADDR;     /* legacy config */
  48
  49        dlen = 1;
  50
  51        /*
  52         * Now try to read the register.
  53         */
  54        if (i2c_read(sensor, reg, 1, data, dlen) != 0)
  55                return -1;
  56
  57        return (int)data[0];
  58}                               /* dtt_read() */
  59
  60int dtt_write(int sensor, int reg, int val)
  61{
  62        int dlen;
  63        uchar data[2];
  64
  65        /*
  66         * Calculate sensor address and register.
  67         */
  68        if (!sensor)
  69                sensor = DTT_I2C_LM63_ADDR;     /* legacy config */
  70
  71        dlen = 1;
  72        data[0] = (char)(val & 0xff);
  73
  74        /*
  75         * Write value to register.
  76         */
  77        if (i2c_write(sensor, reg, 1, data, dlen) != 0)
  78                return 1;
  79
  80        return 0;
  81}                               /* dtt_write() */
  82
  83static int is_lm64(int sensor)
  84{
  85        return sensor && (sensor != DTT_I2C_LM63_ADDR);
  86}
  87
  88int dtt_init_one(int sensor)
  89{
  90        int i;
  91        int val;
  92
  93        struct pwm_lookup_entry pwm_lookup[] = CONFIG_DTT_PWM_LOOKUPTABLE;
  94
  95        /*
  96         * Set PWM Frequency to 2.5% resolution
  97         */
  98        val = 20;
  99        if (dtt_write(sensor, DTT_PWM_FREQ, val) != 0)
 100                return 1;
 101
 102        /*
 103         * Set Tachometer Limit
 104         */
 105        val = CONFIG_DTT_TACH_LIMIT;
 106        if (dtt_write(sensor, DTT_TACHLIM_LSB, val & 0xff) != 0)
 107                return 1;
 108        if (dtt_write(sensor, DTT_TACHLIM_MSB, (val >> 8) & 0xff) != 0)
 109                return 1;
 110
 111        /*
 112         * Make sure PWM Lookup-Table is writeable
 113         */
 114        if (dtt_write(sensor, DTT_FAN_CONFIG, 0x20) != 0)
 115                return 1;
 116
 117        /*
 118         * Setup PWM Lookup-Table
 119         */
 120        for (i = 0; i < ARRAY_SIZE(pwm_lookup); i++) {
 121                int address = DTT_PWM_LOOKUP_BASE + 2 * i;
 122                val = pwm_lookup[i].temp;
 123                if (is_lm64(sensor))
 124                        val -= 16;
 125                if (dtt_write(sensor, address, val) != 0)
 126                        return 1;
 127                val = dtt_read(sensor, address);
 128                val = pwm_lookup[i].pwm;
 129                if (dtt_write(sensor, address + 1, val) != 0)
 130                        return 1;
 131        }
 132
 133        /*
 134         * Enable PWM Lookup-Table, PWM Clock 360 kHz, Tachometer Mode 2
 135         */
 136        val = 0x02;
 137        if (dtt_write(sensor, DTT_FAN_CONFIG, val) != 0)
 138                return 1;
 139
 140        /*
 141         * Enable Tach input
 142         */
 143        val = dtt_read(sensor, DTT_CONFIG) | 0x04;
 144        if (dtt_write(sensor, DTT_CONFIG, val) != 0)
 145                return 1;
 146
 147        return 0;
 148}
 149
 150int dtt_get_temp(int sensor)
 151{
 152        s16 temp = (dtt_read(sensor, DTT_READ_TEMP_RMT_MSB) << 8)
 153            | (dtt_read(sensor, DTT_READ_TEMP_RMT_LSB));
 154
 155        if (is_lm64(sensor))
 156                temp += 16 << 8;
 157
 158        /* Ignore LSB for now, U-Boot only prints natural numbers */
 159        return temp >> 8;
 160}
 161