drivers/net/sk98lin/sklm80.c

   1 /******************************************************************************
   2  *
   3  * Name:        sklm80.c
   4  * Project:     Gigabit Ethernet Adapters, TWSI-Module
   5  * Version:     $Revision: 1.22 $
   6  * Date:        $Date: 2003/10/20 09:08:21 $
   7  * Purpose:     Functions to access Voltage and Temperature Sensor (LM80)
   8  *
   9  ******************************************************************************/
  10
  11 /******************************************************************************
  12  *
  13  *      (C)Copyright 1998-2002 SysKonnect.
  14  *      (C)Copyright 2002-2003 Marvell.
  15  *
  16  *      This program is free software; you can redistribute it and/or modify
  17  *      it under the terms of the GNU General Public License as published by
  18  *      the Free Software Foundation; either version 2 of the License, or
  19  *      (at your option) any later version.
  20  *
  21  *      The information in this file is provided "AS IS" without warranty.
  22  *
  23  ******************************************************************************/
  24
  25 /*
  26         LM80 functions
  27 */
  28 #if (defined(DEBUG) || ((!defined(LINT)) && (!defined(SK_SLIM))))
  29 static const char SysKonnectFileId[] =
  30         "@(#) $Id: sklm80.c,v 1.22 2003/10/20 09:08:21 rschmidt Exp $ (C) Marvell. ";
  31 #endif
  32
  33 #include "h/skdrv1st.h"         /* Driver Specific Definitions */
  34 #include "h/lm80.h"
  35 #include "h/skdrv2nd.h"         /* Adapter Control- and Driver specific Def. */
  36
  37 #define BREAK_OR_WAIT(pAC,IoC,Event)    break
  38
  39 /*
  40  * read a sensors value (LM80 specific)
  41  *
  42  * This function reads a sensors value from the I2C sensor chip LM80.
  43  * The sensor is defined by its index into the sensors database in the struct
  44  * pAC points to.
  45  *
  46  * Returns      1 if the read is completed
  47  *              0 if the read must be continued (I2C Bus still allocated)
  48  */
  49 int SkLm80ReadSensor(
  50 SK_AC           *pAC,   /* Adapter Context */
  51 SK_IOC          IoC,    /* I/O Context needed in level 1 and 2 */
  52 SK_SENSOR       *pSen)  /* Sensor to be read */
  53 {
  54         SK_I32          Value;
  55
  56         switch (pSen->SenState) {
  57         case SK_SEN_IDLE:
  58                 /* Send address to ADDR register */
  59                 SK_I2C_CTL(IoC, I2C_READ, pSen->SenDev, I2C_025K_DEV, pSen->SenReg, 0);
  60
  61                 pSen->SenState = SK_SEN_VALUE ;
  62                 BREAK_OR_WAIT(pAC, IoC, I2C_READ);
  63
  64         case SK_SEN_VALUE:
  65                 /* Read value from data register */
  66                 SK_IN32(IoC, B2_I2C_DATA, ((SK_U32 *)&Value));
  67
  68                 Value &= 0xff; /* only least significant byte is valid */
  69
  70                 /* Do NOT check the Value against the thresholds */
  71                 /* Checking is done in the calling instance */
  72
  73                 if (pSen->SenType == SK_SEN_VOLT) {
  74                         /* Voltage sensor */
  75                         pSen->SenValue = Value * SK_LM80_VT_LSB;
  76                         pSen->SenState = SK_SEN_IDLE ;
  77                         return(1);
  78                 }
  79
  80                 if (pSen->SenType == SK_SEN_FAN) {
  81                         if (Value != 0 && Value != 0xff) {
  82                                 /* Fan speed counter */
  83                                 pSen->SenValue = SK_LM80_FAN_FAKTOR/Value;
  84                         }
  85                         else {
  86                                 /* Indicate Fan error */
  87                                 pSen->SenValue = 0;
  88                         }
  89                         pSen->SenState = SK_SEN_IDLE ;
  90                         return(1);
  91                 }
  92
  93                 /* First: correct the value: it might be negative */
  94                 if ((Value & 0x80) != 0) {
  95                         /* Value is negative */
  96                         Value = Value - 256;
  97                 }
  98
  99                 /* We have a temperature sensor and need to get the signed extension.
 100                  * For now we get the extension from the last reading, so in the normal
 101                  * case we won't see flickering temperatures.
 102                  */
 103                 pSen->SenValue = (Value * SK_LM80_TEMP_LSB) +
 104                         (pSen->SenValue % SK_LM80_TEMP_LSB);
 105
 106                 /* Send address to ADDR register */
 107                 SK_I2C_CTL(IoC, I2C_READ, pSen->SenDev, I2C_025K_DEV, LM80_TEMP_CTRL, 0);
 108
 109                 pSen->SenState = SK_SEN_VALEXT ;
 110                 BREAK_OR_WAIT(pAC, IoC, I2C_READ);
 111
 112         case SK_SEN_VALEXT:
 113                 /* Read value from data register */
 114                 SK_IN32(IoC, B2_I2C_DATA, ((SK_U32 *)&Value));
 115                 Value &= LM80_TEMP_LSB_9; /* only bit 7 is valid */
 116
 117                 /* cut the LSB bit */
 118                 pSen->SenValue = ((pSen->SenValue / SK_LM80_TEMP_LSB) *
 119                         SK_LM80_TEMP_LSB);
 120
 121                 if (pSen->SenValue < 0) {
 122                         /* Value negative: The bit value must be subtracted */
 123                         pSen->SenValue -= ((Value >> 7) * SK_LM80_TEMPEXT_LSB);
 124                 }
 125                 else {
 126                         /* Value positive: The bit value must be added */
 127                         pSen->SenValue += ((Value >> 7) * SK_LM80_TEMPEXT_LSB);
 128                 }
 129
 130                 pSen->SenState = SK_SEN_IDLE ;
 131                 return(1);
 132
 133         default:
 134                 SK_ERR_LOG(pAC, SK_ERRCL_SW, SKERR_I2C_E007, SKERR_I2C_E007MSG);
 135                 return(1);
 136         }
 137
 138         /* Not completed */
 139         return(0);
 140 }
 141