/*

  Version: MPL 1.1/GPL 2.0/LGPL 2.1

  The contents of this file are subject to the Mozilla Public License Version

  1.1 (the "License"); you may not use this file except in compliance with

  the License. You may obtain a copy of the License at

  http://www.mozilla.org/MPL/

  Software distributed under the License is distributed on an "AS IS" basis,

  WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License

  for the specific language governing rights and limitations under the License.

  The Original Code is the Open Hardware Monitor code.

  The Initial Developer of the Original Code is 

  Michael Möller <m.moeller@gmx.ch>.

  Portions created by the Initial Developer are Copyright (C) 2009-2010

  the Initial Developer. All Rights Reserved.

  Contributor(s):

  Alternatively, the contents of this file may be used under the terms of

  either the GNU General Public License Version 2 or later (the "GPL"), or

  the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),

  in which case the provisions of the GPL or the LGPL are applicable instead

  of those above. If you wish to allow use of your version of this file only

  under the terms of either the GPL or the LGPL, and not to allow others to

  use your version of this file under the terms of the MPL, indicate your

  decision by deleting the provisions above and replace them with the notice

  and other provisions required by the GPL or the LGPL. If you do not delete

  the provisions above, a recipient may use your version of this file under

  the terms of any one of the MPL, the GPL or the LGPL.

*/

using System.Globalization;

using System.Text;

namespace OpenHardwareMonitor.Hardware.LPC {

  internal class IT87XX : ISuperIO {

    private readonly ushort address;

    private readonly Chip chip;

    private readonly byte version;

    private readonly ushort gpioAddress;

    private readonly int gpioCount;

    private readonly ushort addressReg;

    private readonly ushort dataReg;

    private readonly float?[] voltages = new float?[0];

    private readonly float?[] temperatures = new float?[0];

    private readonly float?[] fans = new float?[0];

    private readonly float voltageGain;

    private readonly bool has16bitFanCounter;

    // Consts

    private const byte ITE_VENDOR_ID = 0x90;

    // Environment Controller

    private const byte ADDRESS_REGISTER_OFFSET = 0x05;

    private const byte DATA_REGISTER_OFFSET = 0x06;

    // Environment Controller Registers    

    private const byte CONFIGURATION_REGISTER = 0x00;

    private const byte TEMPERATURE_BASE_REG = 0x29;

    private const byte VENDOR_ID_REGISTER = 0x58;

    private const byte FAN_TACHOMETER_DIVISOR_REGISTER = 0x0B;

    private readonly byte[] FAN_TACHOMETER_REG = 

      new byte[] { 0x0d, 0x0e, 0x0f, 0x80, 0x82 };

    private readonly byte[] FAN_TACHOMETER_EXT_REG =

      new byte[] { 0x18, 0x19, 0x1a, 0x81, 0x83 };

    private const byte VOLTAGE_BASE_REG = 0x20;

    private byte ReadByte(byte register, out bool valid) {

      Ring0.WriteIoPort(addressReg, register);

      byte value = Ring0.ReadIoPort(dataReg);

      valid = register == Ring0.ReadIoPort(addressReg);

      return value;

    }

    private bool WriteByte(byte register, byte value) {

      Ring0.WriteIoPort(addressReg, register);

      Ring0.WriteIoPort(dataReg, value);

      return register == Ring0.ReadIoPort(addressReg); 

    } 

    public byte? ReadGPIO(int index) {

      if (index >= gpioCount)

        return null;

      return Ring0.ReadIoPort((ushort)(gpioAddress + index));

    }

    public void WriteGPIO(int index, byte value) {

      if (index >= gpioCount)

        return;

      Ring0.WriteIoPort((ushort)(gpioAddress + index), value);

    }

    public IT87XX(Chip chip, ushort address, ushort gpioAddress, byte version) {

      this.address = address;

      this.chip = chip;

      this.version = version;

      this.addressReg = (ushort)(address + ADDRESS_REGISTER_OFFSET);

      this.dataReg = (ushort)(address + DATA_REGISTER_OFFSET);

      this.gpioAddress = gpioAddress;

      // Check vendor id

      bool valid;

      byte vendorId = ReadByte(VENDOR_ID_REGISTER, out valid);       

      if (!valid || vendorId != ITE_VENDOR_ID)

        return;

      // Bit 0x10 of the configuration register should always be 1

      if ((ReadByte(CONFIGURATION_REGISTER, out valid) & 0x10) == 0)

        return;

      if (!valid)

        return;

      voltages = new float?[9];

      temperatures = new float?[3];

      fans = new float?[5];

      // The IT8721F uses a 12mV resultion ADC, all others 16mV

      if (chip == Chip.IT8721F) {

        voltageGain = 0.012f;

      } else {

        voltageGain = 0.016f;        

      }

      // older IT8721F revision do not have 16-bit fan counters

      if (chip == Chip.IT8712F && version < 8) {

        has16bitFanCounter = false;

      } else {

        has16bitFanCounter = true;

      }

      // Set the number of GPIO sets

      switch (chip) {

        case Chip.IT8712F:

        case Chip.IT8716F:

        case Chip.IT8718F:

        case Chip.IT8726F:

          gpioCount = 5;

          break;

        case Chip.IT8720F:

        case Chip.IT8721F:

          gpioCount = 8;

          break;

      }

    }

    public Chip Chip { get { return chip; } }

    public float?[] Voltages { get { return voltages; } }

    public float?[] Temperatures { get { return temperatures; } }

    public float?[] Fans { get { return fans; } }

    public string GetReport() {

      StringBuilder r = new StringBuilder();

      r.AppendLine("LPC " + this.GetType().Name);

      r.AppendLine();

      r.Append("Chip ID: 0x"); r.AppendLine(chip.ToString("X"));

      r.Append("Chip Version: 0x"); r.AppendLine(

        version.ToString("X", CultureInfo.InvariantCulture));

      r.Append("Base Address: 0x"); r.AppendLine(

        address.ToString("X4", CultureInfo.InvariantCulture));

      r.Append("GPIO Address: 0x"); r.AppendLine(

        gpioAddress.ToString("X4", CultureInfo.InvariantCulture));

      r.AppendLine();

      if (!Ring0.WaitIsaBusMutex(100))

        return r.ToString();

      r.AppendLine("Environment Controller Registers");

      r.AppendLine();

      r.AppendLine("      00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F");

      r.AppendLine();

      for (int i = 0; i <= 0xA; i++) {

        r.Append(" "); 

        r.Append((i << 4).ToString("X2", CultureInfo.InvariantCulture)); 

        r.Append("  ");

        for (int j = 0; j <= 0xF; j++) {

          r.Append(" ");

          bool valid;

          byte value = ReadByte((byte)((i << 4) | j), out valid);

          r.Append(

            valid ? value.ToString("X2", CultureInfo.InvariantCulture) : "??");

        }

        r.AppendLine();

      }

      r.AppendLine();

      r.AppendLine("GPIO Registers");

      r.AppendLine();

      for (int i = 0; i < gpioCount; i++) {

        r.Append(" ");

        r.Append(ReadGPIO(i).Value.ToString("X2",

          CultureInfo.InvariantCulture));

      }

      r.AppendLine();

      r.AppendLine();

      Ring0.ReleaseIsaBusMutex();

      return r.ToString();

    }

    public void Update() {

      if (!Ring0.WaitIsaBusMutex(10))

        return;

      for (int i = 0; i < voltages.Length; i++) {

        bool valid;

        float value = 

          voltageGain * ReadByte((byte)(VOLTAGE_BASE_REG + i), out valid);   

        if (!valid)

          continue;

        if (value > 0)

          voltages[i] = value;  

        else

          voltages[i] = null;

      }

      for (int i = 0; i < temperatures.Length; i++) {

        bool valid;

        sbyte value = (sbyte)ReadByte(

          (byte)(TEMPERATURE_BASE_REG + i), out valid);

        if (!valid)

          continue;

        if (value < sbyte.MaxValue && value > 0)

          temperatures[i] = value;

        else

          temperatures[i] = null;       

      }

      if (has16bitFanCounter) {

        for (int i = 0; i < fans.Length; i++) {

          bool valid;

          int value = ReadByte(FAN_TACHOMETER_REG[i], out valid);

          if (!valid)

            continue;

          value |= ReadByte(FAN_TACHOMETER_EXT_REG[i], out valid) << 8;

          if (!valid)

            continue;

          if (value > 0x3f) {

            fans[i] = (value < 0xffff) ? 1.35e6f / (value * 2) : 0;

          } else {

            fans[i] = null;

          }

        }

      } else {

        for (int i = 0; i < fans.Length; i++) {

          bool valid;

          int value = ReadByte(FAN_TACHOMETER_REG[i], out valid);

          if (!valid)

            continue;

          int divisor = 2;

          if (i < 2) {

            int divisors = ReadByte(FAN_TACHOMETER_DIVISOR_REGISTER, out valid);

            if (!valid)

              continue;

            divisor = 1 << ((divisors >> (3 * i)) & 0x7);

          }

          if (value > 0) {

            fans[i] = (value < 0xff) ? 1.35e6f / (value * divisor) : 0;

          } else {

            fans[i] = null;

          }

        }

      }

      Ring0.ReleaseIsaBusMutex();

    }

  } 

}