Copyright (C) 2002-2011 Sentelic Corporation.
  Last update: Dec-07-2011

  
  ==============================================================================
  * Finger Sensing Pad Intellimouse Mode(scrolling wheel, 4th and 5th buttons)
  ==============================================================================
  A) MSID 4: Scrolling wheel mode plus Forward page(4th button) and Backward
     page (5th button)
  @1. Set sample rate to 200;
  @2. Set sample rate to 200;
  @3. Set sample rate to 80;
  @4. Issuing the "Get device ID" command (0xF2) and waits for the response;
  @5. FSP will respond 0x04.
  
  Packet 1
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |Y|X|y|x|1|M|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 | | |B|F|W|W|W|W|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7 => Y overflow
          Bit6 => X overflow
          Bit5 => Y sign bit
          Bit4 => X sign bit
          Bit3 => 1
          Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X Movement(9-bit 2's complement integers)
  Byte 3: Y Movement(9-bit 2's complement integers)
  Byte 4: Bit3~Bit0 => the scrolling wheel's movement since the last data report.
                       valid values, -8 ~ +7
          Bit4 => 1 = 4th mouse button is pressed, Forward one page.
                  0 = 4th mouse button is not pressed.
          Bit5 => 1 = 5th mouse button is pressed, Backward one page.
                  0 = 5th mouse button is not pressed.
  
  B) MSID 6: Horizontal and Vertical scrolling.
  @ Set bit 1 in register 0x40 to 1
  
  # FSP replaces scrolling wheel's movement as 4 bits to show horizontal and
    vertical scrolling.
  
  Packet 1
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|

    1   |Y|X|y|x|1|M|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 | | |B|F|r|l|u|d|

        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7 => Y overflow
          Bit6 => X overflow
          Bit5 => Y sign bit
          Bit4 => X sign bit
          Bit3 => 1
          Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X Movement(9-bit 2's complement integers)
  Byte 3: Y Movement(9-bit 2's complement integers)
  Byte 4: Bit0 => the Vertical scrolling movement downward.
  	Bit1 => the Vertical scrolling movement upward.

  	Bit2 => the Horizontal scrolling movement leftward.
  	Bit3 => the Horizontal scrolling movement rightward.

          Bit4 => 1 = 4th mouse button is pressed, Forward one page.
                  0 = 4th mouse button is not pressed.
          Bit5 => 1 = 5th mouse button is pressed, Backward one page.
                  0 = 5th mouse button is not pressed.
  
  C) MSID 7:

  # FSP uses 2 packets (8 Bytes) to represent Absolute Position.

    so we have PACKET NUMBER to identify packets.
    If PACKET NUMBER is 0, the packet is Packet 1.
    If PACKET NUMBER is 1, the packet is Packet 2.
    Please count this number in program.
  
  # MSID6 special packet will be enable at the same time when enable MSID 7.
  
  ==============================================================================
  * Absolute position for STL3886-G0.
  ==============================================================================
  @ Set bit 2 or 3 in register 0x40 to 1
  @ Set bit 6 in register 0x40 to 1
  
  Packet 1 (ABSOLUTE POSITION)
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|V|1|1|M|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |r|l|d|u|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordination packet
                    => 10, Notify packet
          Bit5 => valid bit
          Bit4 => 1
          Bit3 => 1
          Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
          Bit3~Bit2 => X coordinate (ypos[1:0])
          Bit4 => scroll up
          Bit5 => scroll down
          Bit6 => scroll left
          Bit7 => scroll right
  
  Notify Packet for G0
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |1|0|0|1|1|M|R|L|  2  |C|C|C|C|C|C|C|C|  3 |M|M|M|M|M|M|M|M|  4 |0|0|0|0|0|0|0|0|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordination packet
                    => 10, Notify packet
          Bit5 => 0
          Bit4 => 1
          Bit3 => 1
          Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: Message Type => 0x5A (Enable/Disable status packet)
          Mode Type => 0xA5 (Normal/Icon mode status)
  Byte 3: Message Type => 0x00 (Disabled)
                       => 0x01 (Enabled)
          Mode Type    => 0x00 (Normal)
                       => 0x01 (Icon)
  Byte 4: Bit7~Bit0 => Don't Care
  
  ==============================================================================

  * Absolute position for STL3888-Ax.

  ==============================================================================
  Packet 1 (ABSOLUTE POSITION)
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|V|A|1|L|0|1|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |x|x|y|y|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordination packet
                    => 10, Notify packet

                    => 11, Normal data packet with on-pad click

          Bit5 => Valid bit, 0 means that the coordinate is invalid or finger up.
                  When both fingers are up, the last two reports have zero valid
                  bit.
          Bit4 => arc
          Bit3 => 1
          Bit2 => Left Button, 1 is pressed, 0 is released.
          Bit1 => 0
          Bit0 => 1
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
          Bit3~Bit2 => X coordinate (ypos[1:0])
          Bit5~Bit4 => y1_g
          Bit7~Bit6 => x1_g
  
  Packet 2 (ABSOLUTE POSITION)
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|V|A|1|R|1|0|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |x|x|y|y|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordinates packet
                    => 10, Notify packet

                    => 11, Normal data packet with on-pad click

          Bit5 => Valid bit, 0 means that the coordinate is invalid or finger up.
                  When both fingers are up, the last two reports have zero valid
                  bit.
          Bit4 => arc
          Bit3 => 1
          Bit2 => Right Button, 1 is pressed, 0 is released.
          Bit1 => 1
          Bit0 => 0
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
          Bit3~Bit2 => X coordinate (ypos[1:0])
          Bit5~Bit4 => y2_g
          Bit7~Bit6 => x2_g

  Notify Packet for STL3888-Ax

     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |1|0|1|P|1|M|R|L|  2  |C|C|C|C|C|C|C|C|  3 |0|0|F|F|0|0|0|i|  4 |r|l|d|u|0|0|0|0|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet

                    => 01, Absolute coordinates packet

                    => 10, Notify packet

                    => 11, Normal data packet with on-pad click

          Bit5 => 1
          Bit4 => when in absolute coordinates mode (valid when EN_PKT_GO is 1):
                  0: left button is generated by the on-pad command
                  1: left button is generated by the external button
          Bit3 => 1
          Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: Message Type => 0xB7 (Multi Finger, Multi Coordinate mode)
  Byte 3: Bit7~Bit6 => Don't care
          Bit5~Bit4 => Number of fingers
          Bit3~Bit1 => Reserved
          Bit0 => 1: enter gesture mode; 0: leaving gesture mode
  Byte 4: Bit7 => scroll right button
          Bit6 => scroll left button
          Bit5 => scroll down button
          Bit4 => scroll up button

              * Note that if gesture and additional button (Bit4~Bit7)

                happen at the same time, the button information will not
                be sent.
          Bit3~Bit0 => Reserved
  
  Sample sequence of Multi-finger, Multi-coordinate mode:
  
  	notify packet (valid bit == 1), abs pkt 1, abs pkt 2, abs pkt 1,
  	abs pkt 2, ..., notify packet (valid bit == 0)
  
  ==============================================================================
  * Absolute position for STL3888-B0.
  ==============================================================================
  Packet 1(ABSOLUTE POSITION)
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|V|F|1|0|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |r|l|u|d|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordinates packet
                    => 10, Notify packet

                    => 11, Normal data packet with on-pad click

          Bit5 => Valid bit, 0 means that the coordinate is invalid or finger up.
                  When both fingers are up, the last two reports have zero valid
                  bit.
          Bit4 => finger up/down information. 1: finger down, 0: finger up.
          Bit3 => 1
          Bit2 => finger index, 0 is the first finger, 1 is the second finger.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
          Bit3~Bit2 => X coordinate (ypos[1:0])
          Bit4 => scroll down button
          Bit5 => scroll up button
          Bit6 => scroll left button
          Bit7 => scroll right button
  
  Packet 2 (ABSOLUTE POSITION)
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|V|F|1|1|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |r|l|u|d|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordination packet
                    => 10, Notify packet

                    => 11, Normal data packet with on-pad click

          Bit5 => Valid bit, 0 means that the coordinate is invalid or finger up.
                  When both fingers are up, the last two reports have zero valid
                  bit.
          Bit4 => finger up/down information. 1: finger down, 0: finger up.
          Bit3 => 1
          Bit2 => finger index, 0 is the first finger, 1 is the second finger.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
          Bit3~Bit2 => X coordinate (ypos[1:0])
          Bit4 => scroll down button
          Bit5 => scroll up button
          Bit6 => scroll left button
          Bit7 => scroll right button
  
  Notify Packet for STL3888-B0
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |1|0|1|P|1|M|R|L|  2  |C|C|C|C|C|C|C|C|  3 |0|0|F|F|0|0|0|i|  4 |r|l|u|d|0|0|0|0|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordination packet
                    => 10, Notify packet

                    => 11, Normal data packet with on-pad click

          Bit5 => 1

          Bit4 => when in absolute coordinates mode (valid when EN_PKT_GO is 1):

                  0: left button is generated by the on-pad command
                  1: left button is generated by the external button
          Bit3 => 1
          Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
          Bit1 => Right Button, 1 is pressed, 0 is not pressed.
          Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: Message Type => 0xB7 (Multi Finger, Multi Coordinate mode)
  Byte 3: Bit7~Bit6 => Don't care
          Bit5~Bit4 => Number of fingers
          Bit3~Bit1 => Reserved
          Bit0 => 1: enter gesture mode; 0: leaving gesture mode
  Byte 4: Bit7 => scroll right button
          Bit6 => scroll left button
          Bit5 => scroll up button
          Bit4 => scroll down button
              * Note that if gesture and additional button(Bit4~Bit7)
                happen at the same time, the button information will not
                be sent.

          Bit3~Bit0 => Reserved
  
  Sample sequence of Multi-finger, Multi-coordinate mode:
  
  	notify packet (valid bit == 1), abs pkt 1, abs pkt 2, abs pkt 1,

  	abs pkt 2, ..., notify packet (valid bit == 0)

  
  ==============================================================================

  * Absolute position for STL3888-Cx and STL3888-Dx.
  ==============================================================================
  Single Finger, Absolute Coordinate Mode (SFAC)
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|0|P|1|M|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |r|l|B|F|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordinates packet
                    => 10, Notify packet
  	Bit5 => Coordinate mode(always 0 in SFAC mode):
  		0: single-finger absolute coordinates (SFAC) mode
  		1: multi-finger, multiple coordinates (MFMC) mode
  	Bit4 => 0: The LEFT button is generated by on-pad command (OPC)
  		1: The LEFT button is generated by external button
  		Default is 1 even if the LEFT button is not pressed.
  	Bit3 => Always 1, as specified by PS/2 protocol.
  	Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
  	Bit1 => Right Button, 1 is pressed, 0 is not pressed.
  	Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
  	Bit3~Bit2 => X coordinate (ypos[1:0])
  	Bit4 => 4th mouse button(forward one page)
  	Bit5 => 5th mouse button(backward one page)
  	Bit6 => scroll left button
  	Bit7 => scroll right button
  
  Multi Finger, Multiple Coordinates Mode (MFMC):
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |0|1|1|P|1|F|R|L|  2  |X|X|X|X|X|X|X|X|  3 |Y|Y|Y|Y|Y|Y|Y|Y|  4 |r|l|B|F|X|X|Y|Y|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordination packet
                    => 10, Notify packet
  	Bit5 => Coordinate mode (always 1 in MFMC mode):
  		0: single-finger absolute coordinates (SFAC) mode
  		1: multi-finger, multiple coordinates (MFMC) mode
  	Bit4 => 0: The LEFT button is generated by on-pad command (OPC)
  		1: The LEFT button is generated by external button
  		Default is 1 even if the LEFT button is not pressed.
  	Bit3 => Always 1, as specified by PS/2 protocol.
  	Bit2 => Finger index, 0 is the first finger, 1 is the second finger.
  		If bit 1 and 0 are all 1 and bit 4 is 0, the middle external
  		button is pressed.
  	Bit1 => Right Button, 1 is pressed, 0 is not pressed.
  	Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: X coordinate (xpos[9:2])
  Byte 3: Y coordinate (ypos[9:2])
  Byte 4: Bit1~Bit0 => Y coordinate (xpos[1:0])
  	Bit3~Bit2 => X coordinate (ypos[1:0])
  	Bit4 => 4th mouse button(forward one page)
  	Bit5 => 5th mouse button(backward one page)
  	Bit6 => scroll left button
  	Bit7 => scroll right button
  
    When one of the two fingers is up, the device will output four consecutive
  MFMC#0 report packets with zero X and Y to represent 1st finger is up or
  four consecutive MFMC#1 report packets with zero X and Y to represent that
  the 2nd finger is up.  On the other hand, if both fingers are up, the device
  will output four consecutive single-finger, absolute coordinate(SFAC) packets
  with zero X and Y.
  
  Notify Packet for STL3888-Cx/Dx
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |1|0|0|P|1|M|R|L|  2  |C|C|C|C|C|C|C|C|  3 |0|0|F|F|0|0|0|i|  4 |r|l|u|d|0|0|0|0|
        |---------------|     |---------------|    |---------------|    |---------------|
  
  Byte 1: Bit7~Bit6 => 00, Normal data packet
                    => 01, Absolute coordinates packet
                    => 10, Notify packet
  	Bit5 => Always 0
  	Bit4 => 0: The LEFT button is generated by on-pad command(OPC)
  		1: The LEFT button is generated by external button
  		Default is 1 even if the LEFT button is not pressed.
  	Bit3 => 1
  	Bit2 => Middle Button, 1 is pressed, 0 is not pressed.
  	Bit1 => Right Button, 1 is pressed, 0 is not pressed.
  	Bit0 => Left Button, 1 is pressed, 0 is not pressed.
  Byte 2: Message type:
  	0xba => gesture information
  	0xc0 => one finger hold-rotating gesture
  Byte 3: The first parameter for the received message:
  	0xba => gesture ID (refer to the 'Gesture ID' section)
  	0xc0 => region ID
  Byte 4: The second parameter for the received message:
  	0xba => N/A
  	0xc0 => finger up/down information
  
  Sample sequence of Multi-finger, Multi-coordinates mode:
  
  	notify packet (valid bit == 1), MFMC packet 1 (byte 1, bit 2 == 0),
  	MFMC packet 2 (byte 1, bit 2 == 1), MFMC packet 1, MFMC packet 2,
  	..., notify packet (valid bit == 0)
  
  	That is, when the device is in MFMC mode, the host will receive
  	interleaved absolute coordinate packets for each finger.
  
  ==============================================================================

  * FSP Enable/Disable packet
  ==============================================================================
     Bit 7 6 5 4 3 2 1 0       7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0      7 6 5 4 3 2 1 0
  BYTE  |---------------|BYTE |---------------|BYTE|---------------|BYTE|---------------|
    1   |Y|X|0|0|1|M|R|L|  2  |0|1|0|1|1|0|1|E|  3 | | | | | | | | |  4 | | | | | | | | |
        |---------------|     |---------------|    |---------------|    |---------------|
  
  FSP will send out enable/disable packet when FSP receive PS/2 enable/disable
  command. Host will receive the packet which Middle, Right, Left button will
  be set. The packet only use byte 0 and byte 1 as a pattern of original packet.
  Ignore the other bytes of the packet.
  
  Byte 1: Bit7 => 0, Y overflow
          Bit6 => 0, X overflow
  	Bit5 => 0, Y sign bit
          Bit4 => 0, X sign bit
  	Bit3 => 1
  	Bit2 => 1, Middle Button
          Bit1 => 1, Right Button
          Bit0 => 1, Left Button
  Byte 2: Bit7~1 => (0101101b)
          Bit0 => 1 = Enable
  		0 = Disable
  Byte 3: Don't care
  Byte 4: Don't care (MOUSE ID 3, 4)
  Byte 5~8: Don't care (Absolute packet)
  
  ==============================================================================
  * PS/2 Command Set
  ==============================================================================
  
  FSP supports basic PS/2 commanding set and modes, refer to following URL for
  details about PS/2 commands:

  http://www.computer-engineering.org/ps2mouse/

  
  ==============================================================================
  * Programming Sequence for Determining Packet Parsing Flow
  ==============================================================================
  1. Identify FSP by reading device ID(0x00) and version(0x01) register

  2a. For FSP version < STL3888 Cx, determine number of buttons by reading
      the 'test mode status' (0x20) register:

  	buttons = reg[0x20] & 0x30

  
  	if buttons == 0x30 or buttons == 0x20:
  		# two/four buttons
  		Refer to 'Finger Sensing Pad PS/2 Mouse Intellimouse'
  		section A for packet parsing detail(ignore byte 4, bit ~ 7)
  	elif buttons == 0x10:
  		# 6 buttons
  		Refer to 'Finger Sensing Pad PS/2 Mouse Intellimouse'
  		section B for packet parsing detail
  	elif buttons == 0x00:
  		# 6 buttons
  		Refer to 'Finger Sensing Pad PS/2 Mouse Intellimouse'
  		section A for packet parsing detail

  2b. For FSP version >= STL3888 Cx:
  	Refer to 'Finger Sensing Pad PS/2 Mouse Intellimouse'
  	section A for packet parsing detail (ignore byte 4, bit ~ 7)

  ==============================================================================
  * Programming Sequence for Register Reading/Writing
  ==============================================================================
  
  Register inversion requirement:
  
    Following values needed to be inverted(the '~' operator in C) before being
  sent to FSP:

  	0xe8, 0xe9, 0xee, 0xf2, 0xf3 and 0xff.

  
  Register swapping requirement:
  
    Following values needed to have their higher 4 bits and lower 4 bits being
  swapped before being sent to FSP:
  
  	10, 20, 40, 60, 80, 100 and 200.
  
  Register reading sequence:
  
  	1. send 0xf3 PS/2 command to FSP;
  
  	2. send 0x66 PS/2 command to FSP;
  
  	3. send 0x88 PS/2 command to FSP;
  
  	4. send 0xf3 PS/2 command to FSP;
  
  	5. if the register address being to read is not required to be
  	inverted(refer to the 'Register inversion requirement' section),
  	goto step 6
  
  	5a. send 0x68 PS/2 command to FSP;
  
  	5b. send the inverted register address to FSP and goto step 8;
  
  	6. if the register address being to read is not required to be
  	swapped(refer to the 'Register swapping requirement' section),
  	goto step 7
  
  	6a. send 0xcc PS/2 command to FSP;
  
  	6b. send the swapped register address to FSP and goto step 8;
  
  	7. send 0x66 PS/2 command to FSP;
  
  	7a. send the original register address to FSP and goto step 8;
  
  	8. send 0xe9(status request) PS/2 command to FSP;

  	9. the 4th byte of the response read from FSP should be the
  	requested register value(?? indicates don't care byte):
  
  		host: 0xe9
  		3888: 0xfa (??) (??) (val)
  
  	* Note that since the Cx release, the hardware will return 1's
  	complement of the register value at the 3rd byte of status request
  	result:
  
  		host: 0xe9
  		3888: 0xfa (??) (~val) (val)

  
  Register writing sequence:
  
  	1. send 0xf3 PS/2 command to FSP;
  
  	2. if the register address being to write is not required to be
  	inverted(refer to the 'Register inversion requirement' section),
  	goto step 3
  
  	2a. send 0x74 PS/2 command to FSP;
  
  	2b. send the inverted register address to FSP and goto step 5;
  
  	3. if the register address being to write is not required to be
  	swapped(refer to the 'Register swapping requirement' section),
  	goto step 4
  
  	3a. send 0x77 PS/2 command to FSP;
  
  	3b. send the swapped register address to FSP and goto step 5;
  
  	4. send 0x55 PS/2 command to FSP;
  
  	4a. send the register address to FSP and goto step 5;
  
  	5. send 0xf3 PS/2 command to FSP;
  
  	6. if the register value being to write is not required to be
  	inverted(refer to the 'Register inversion requirement' section),
  	goto step 7
  
  	6a. send 0x47 PS/2 command to FSP;
  
  	6b. send the inverted register value to FSP and goto step 9;
  
  	7. if the register value being to write is not required to be
  	swapped(refer to the 'Register swapping requirement' section),
  	goto step 8
  
  	7a. send 0x44 PS/2 command to FSP;
  
  	7b. send the swapped register value to FSP and goto step 9;
  
  	8. send 0x33 PS/2 command to FSP;
  
  	8a. send the register value to FSP;
  
  	9. the register writing sequence is completed.

  	* Note that since the Cx release, the hardware will return 1's
  	complement of the register value at the 3rd byte of status request
  	result. Host can optionally send another 0xe9 (status request) PS/2
  	command to FSP at the end of register writing to verify that the
  	register writing operation is successful (?? indicates don't care
  	byte):
  
  		host: 0xe9
  		3888: 0xfa (??) (~val) (val)
  
  ==============================================================================
  * Programming Sequence for Page Register Reading/Writing
  ==============================================================================
  
    In order to overcome the limitation of maximum number of registers
  supported, the hardware separates register into different groups called
  'pages.' Each page is able to include up to 255 registers.
  
    The default page after power up is 0x82; therefore, if one has to get
  access to register 0x8301, one has to use following sequence to switch
  to page 0x83, then start reading/writing from/to offset 0x01 by using
  the register read/write sequence described in previous section.
  
  Page register reading sequence:
  
  	1. send 0xf3 PS/2 command to FSP;
  
  	2. send 0x66 PS/2 command to FSP;
  
  	3. send 0x88 PS/2 command to FSP;
  
  	4. send 0xf3 PS/2 command to FSP;
  
  	5. send 0x83 PS/2 command to FSP;
  
  	6. send 0x88 PS/2 command to FSP;
  
  	7. send 0xe9(status request) PS/2 command to FSP;
  
  	8. the response read from FSP should be the requested page value.
  
  Page register writing sequence:
  
  	1. send 0xf3 PS/2 command to FSP;
  
  	2. send 0x38 PS/2 command to FSP;
  
  	3. send 0x88 PS/2 command to FSP;
  
  	4. send 0xf3 PS/2 command to FSP;
  
  	5. if the page address being written is not required to be
  	inverted(refer to the 'Register inversion requirement' section),
  	goto step 6
  
  	5a. send 0x47 PS/2 command to FSP;
  
  	5b. send the inverted page address to FSP and goto step 9;
  
  	6. if the page address being written is not required to be
  	swapped(refer to the 'Register swapping requirement' section),
  	goto step 7
  
  	6a. send 0x44 PS/2 command to FSP;
  
  	6b. send the swapped page address to FSP and goto step 9;
  
  	7. send 0x33 PS/2 command to FSP;
  
  	8. send the page address to FSP;
  
  	9. the page register writing sequence is completed.
  
  ==============================================================================
  * Gesture ID
  ==============================================================================
  
    Unlike other devices which sends multiple fingers' coordinates to host,
  FSP processes multiple fingers' coordinates internally and convert them
  into a 8 bits integer, namely 'Gesture ID.'  Following is a list of
  supported gesture IDs:
  
  	ID	Description
  	0x86	2 finger straight up
  	0x82	2 finger straight down
  	0x80	2 finger straight right
  	0x84	2 finger straight left
  	0x8f	2 finger zoom in
  	0x8b	2 finger zoom out
  	0xc0	2 finger curve, counter clockwise
  	0xc4	2 finger curve, clockwise
  	0x2e	3 finger straight up
  	0x2a	3 finger straight down
  	0x28	3 finger straight right
  	0x2c	3 finger straight left
  	0x38	palm

  ==============================================================================
  * Register Listing
  ==============================================================================

    Registers are represented in 16 bits values. The higher 8 bits represent
  the page address and the lower 8 bits represent the relative offset within
  that particular page.  Refer to the 'Programming Sequence for Page Register
  Reading/Writing' section for instructions on how to change current page
  address.

  offset	width		default	r/w	name

  0x8200	bit7~bit0	0x01	RO	device ID

  0x8201	bit7~bit0		RW	version ID
  					0xc1: STL3888 Ax
  					0xd0 ~ 0xd2: STL3888 Bx
  					0xe0 ~ 0xe1: STL3888 Cx
  					0xe2 ~ 0xe3: STL3888 Dx

  0x8202	bit7~bit0	0x01	RO	vendor ID

  0x8203	bit7~bit0	0x01	RO	product ID

  0x8204	bit3~bit0	0x01	RW	revision ID

  0x820b					test mode status 1
  	bit3		1	RO	0: rotate 180 degree
  					1: no rotation
  					*only supported by H/W prior to Cx

  0x820f					register file page control
  	bit2		0	RW	1: rotate 180 degree
  					0: no rotation
  					*supported since Cx

  	bit0		0	RW	1 to enable page 1 register files

  					*only supported by H/W prior to Cx

  0x8210				RW	system control 1

  	bit0		1	RW	Reserved, must be 1
  	bit1		0	RW	Reserved, must be 0

  	bit4		0	RW	Reserved, must be 0
  	bit5		1	RW	register clock gating enable

  					0: read only, 1: read/write enable
  	(Note that following registers does not require clock gating being
  	enabled prior to write: 05 06 07 08 09 0c 0f 10 11 12 16 17 18 23 2e

  	40 41 42 43.  In addition to that, this bit must be 1 when gesture
  	mode is enabled)

  0x8220					test mode status
  	bit5~bit4		RO	number of buttons
  					11 => 2, lbtn/rbtn
  					10 => 4, lbtn/rbtn/scru/scrd
  					01 => 6, lbtn/rbtn/scru/scrd/scrl/scrr
  					00 => 6, lbtn/rbtn/scru/scrd/fbtn/bbtn
  					*only supported by H/W prior to Cx
  
  0x8231				RW	on-pad command detection

  	bit7		0	RW	on-pad command left button down tag
  					enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx

  0x8234				RW	on-pad command control 5

  	bit4~bit0	0x05	RW	XLO in 0s/4/1, so 03h = 0010.1b = 2.5
  	(Note that position unit is in 0.5 scanline)

  					*only supported by H/W prior to Cx

  
  	bit7		0	RW	on-pad tap zone enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx

  0x8235				RW	on-pad command control 6

  	bit4~bit0	0x1d	RW	XHI in 0s/4/1, so 19h = 1100.1b = 12.5
  	(Note that position unit is in 0.5 scanline)

  					*only supported by H/W prior to Cx

  0x8236				RW	on-pad command control 7

  	bit4~bit0	0x04	RW	YLO in 0s/4/1, so 03h = 0010.1b = 2.5
  	(Note that position unit is in 0.5 scanline)

  					*only supported by H/W prior to Cx

  0x8237				RW	on-pad command control 8

  	bit4~bit0	0x13	RW	YHI in 0s/4/1, so 11h = 1000.1b = 8.5
  	(Note that position unit is in 0.5 scanline)

  					*only supported by H/W prior to Cx

  0x8240				RW	system control 5

  	bit1		0	RW	FSP Intellimouse mode enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx

  
  	bit2		0	RW	movement + abs. coordinate mode enable
  					0: disable, 1: enable
  	(Note that this function has the functionality of bit 1 even when
  	bit 1 is not set. However, the format is different from that of bit 1.
  	In addition, when bit 1 and bit 2 are set at the same time, bit 2 will
  	override bit 1.)

  					*only supported by H/W prior to Cx

  
  	bit3		0	RW	abs. coordinate only mode enable
  					0: disable, 1: enable
  	(Note that this function has the functionality of bit 1 even when
  	bit 1 is not set. However, the format is different from that of bit 1.
  	In addition, when bit 1, bit 2 and bit 3 are set at the same time,
  	bit 3 will override bit 1 and 2.)

  					*only supported by H/W prior to Cx

  
  	bit5		0	RW	auto switch enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx

  
  	bit6		0	RW	G0 abs. + notify packet format enable
  					0: disable, 1: enable
  	(Note that the absolute/relative coordinate output still depends on
  	bit 2 and 3.  That is, if any of those bit is 1, host will receive
  	absolute coordinates; otherwise, host only receives packets with
  	relative coordinate.)

  					*only supported by H/W prior to Cx

  	bit7		0	RW	EN_PS2_F2: PS/2 gesture mode 2nd
  					finger packet enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx

  0x8243				RW	on-pad control

  	bit0		0	RW	on-pad control enable
  					0: disable, 1: enable
  	(Note that if this bit is cleared, bit 3/5 will be ineffective)

  					*only supported by H/W prior to Cx

  
  	bit3		0	RW	on-pad fix vertical scrolling enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx

  
  	bit5		0	RW	on-pad fix horizontal scrolling enable
  					0: disable, 1: enable

  					*only supported by H/W prior to Cx
  
  0x8290				RW	software control register 1
  	bit0		0	RW	absolute coordination mode
  					0: disable, 1: enable
  					*supported since Cx
  
  	bit1		0	RW	gesture ID output
  					0: disable, 1: enable
  					*supported since Cx
  
  	bit2		0	RW	two fingers' coordinates output
  					0: disable, 1: enable
  					*supported since Cx
  
  	bit3		0	RW	finger up one packet output
  					0: disable, 1: enable
  					*supported since Cx
  
  	bit4		0	RW	absolute coordination continuous mode
  					0: disable, 1: enable
  					*supported since Cx
  
  	bit6~bit5	00	RW	gesture group selection
  					00: basic
  					01: suite
  					10: suite pro
  					11: advanced
  					*supported since Cx
  
  	bit7		0	RW	Bx packet output compatible mode
  					0: disable, 1: enable					*supported since Cx
  					*supported since Cx
  
  
  0x833d				RW	on-pad command control 1
  	bit7		1	RW	on-pad command detection enable
  					0: disable, 1: enable
  					*supported since Cx
  
  0x833e				RW	on-pad command detection
  	bit7		0	RW	on-pad command left button down tag
  					enable. Works only in H/W based PS/2
  					data packet mode.
  					0: disable, 1: enable
  					*supported since Cx