Copyright (C) 2002-2008 Sentelic Corporation.
Last update: Oct-31-2008

==============================================================================
* 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|l|r|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 Vertical scrolling movement rightward.
	Bit3 => the Vertical scrolling movement leftward.
        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) data 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-A0.
==============================================================================
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
        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
        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-A0
   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 coordination packet
                  => 10, Notify packet
        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)

==============================================================================
* 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/index.php?title=PS/2_Mouse_Interface

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

2. Determine number of buttons by reading status2 (0x0b) register

	buttons = reg[0x0b] & 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

==============================================================================
* Programming Sequence for Register Reading/Writing
==============================================================================

Register inversion requirement:

  Following values needed to be inverted(the '~' operator in C) before being
sent to FSP:

	0xe9, 0xee, 0xf2 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 response read from FSP should be the requested register value.

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.

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

offset	width		default	r/w	name
0x00	bit7~bit0	0x01	RO	device ID

0x01	bit7~bit0	0xc0	RW	version ID

0x02	bit7~bit0	0x01	RO	vendor ID

0x03	bit7~bit0	0x01	RO	product ID

0x04	bit3~bit0	0x01	RW	revision ID

0x0b				RO	test mode status 1
	bit3		1	RO	0: rotate 180 degree, 1: no rotation

	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

0x0f				RW	register file page control
	bit0		0	RW	1 to enable page 1 register files

0x10				RW	system control 1
	bit0		1	RW	Reserved, must be 1
	bit1		0	RW	Reserved, must be 0
	bit4		1	RW	Reserved, must be 0
	bit5		0	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.)

0x31				RW	on-pad command detection
	bit7		0	RW	on-pad command left button down tag
					enable
					0: disable, 1: enable

0x34				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)

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

0x35				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)

0x36				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)

0x37				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)

0x40				RW	system control 5
	bit1		0	RW	FSP Intellimouse mode enable
					0: disable, 1: enable

	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.)

	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.)

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

	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.)

0x43				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)

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

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