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diff --git a/Documentation/input/alps.txt b/Documentation/input/alps.txt deleted file mode 100644 index ae8ba9a74ce..00000000000 --- a/Documentation/input/alps.txt +++ /dev/null @@ -1,189 +0,0 @@ -ALPS Touchpad Protocol ----------------------- - -Introduction ------------- - -Currently the ALPS touchpad driver supports four protocol versions in use by -ALPS touchpads, called versions 1, 2, 3, and 4. Information about the various -protocol versions is contained in the following sections. - -Detection ---------- - -All ALPS touchpads should respond to the "E6 report" command sequence: -E8-E6-E6-E6-E9. An ALPS touchpad should respond with either 00-00-0A or -00-00-64 if no buttons are pressed. The bits 0-2 of the first byte will be 1s -if some buttons are pressed. - -If the E6 report is successful, the touchpad model is identified using the "E7 -report" sequence: E8-E7-E7-E7-E9. The response is the model signature and is -matched against known models in the alps_model_data_array. - -With protocol versions 3 and 4, the E7 report model signature is always -73-02-64. To differentiate between these versions, the response from the -"Enter Command Mode" sequence must be inspected as described below. - -Command Mode ------------- - -Protocol versions 3 and 4 have a command mode that is used to read and write -one-byte device registers in a 16-bit address space. The command sequence -EC-EC-EC-E9 places the device in command mode, and the device will respond -with 88-07 followed by a third byte. This third byte can be used to determine -whether the devices uses the version 3 or 4 protocol. - -To exit command mode, PSMOUSE_CMD_SETSTREAM (EA) is sent to the touchpad. - -While in command mode, register addresses can be set by first sending a -specific command, either EC for v3 devices or F5 for v4 devices. Then the -address is sent one nibble at a time, where each nibble is encoded as a -command with optional data. This enoding differs slightly between the v3 and -v4 protocols. - -Once an address has been set, the addressed register can be read by sending -PSMOUSE_CMD_GETINFO (E9). The first two bytes of the response contains the -address of the register being read, and the third contains the value of the -register. Registers are written by writing the value one nibble at a time -using the same encoding used for addresses. - -Packet Format -------------- - -In the following tables, the following notation is used. - - CAPITALS = stick, miniscules = touchpad - -?'s can have different meanings on different models, such as wheel rotation, -extra buttons, stick buttons on a dualpoint, etc. - -PS/2 packet format ------------------- - - byte 0: 0 0 YSGN XSGN 1 M R L - byte 1: X7 X6 X5 X4 X3 X2 X1 X0 - byte 2: Y7 Y6 Y5 Y4 Y3 Y2 Y1 Y0 - -Note that the device never signals overflow condition. - -ALPS Absolute Mode - Protocol Verion 1 --------------------------------------- - - byte 0: 1 0 0 0 1 x9 x8 x7 - byte 1: 0 x6 x5 x4 x3 x2 x1 x0 - byte 2: 0 ? ? l r ? fin ges - byte 3: 0 ? ? ? ? y9 y8 y7 - byte 4: 0 y6 y5 y4 y3 y2 y1 y0 - byte 5: 0 z6 z5 z4 z3 z2 z1 z0 - -ALPS Absolute Mode - Protocol Version 2 ---------------------------------------- - - byte 0: 1 ? ? ? 1 ? ? ? - byte 1: 0 x6 x5 x4 x3 x2 x1 x0 - byte 2: 0 x10 x9 x8 x7 ? fin ges - byte 3: 0 y9 y8 y7 1 M R L - byte 4: 0 y6 y5 y4 y3 y2 y1 y0 - byte 5: 0 z6 z5 z4 z3 z2 z1 z0 - -Dualpoint device -- interleaved packet format ---------------------------------------------- - - byte 0: 1 1 0 0 1 1 1 1 - byte 1: 0 x6 x5 x4 x3 x2 x1 x0 - byte 2: 0 x10 x9 x8 x7 0 fin ges - byte 3: 0 0 YSGN XSGN 1 1 1 1 - byte 4: X7 X6 X5 X4 X3 X2 X1 X0 - byte 5: Y7 Y6 Y5 Y4 Y3 Y2 Y1 Y0 - byte 6: 0 y9 y8 y7 1 m r l - byte 7: 0 y6 y5 y4 y3 y2 y1 y0 - byte 8: 0 z6 z5 z4 z3 z2 z1 z0 - -ALPS Absolute Mode - Protocol Version 3 ---------------------------------------- - -ALPS protocol version 3 has three different packet formats. The first two are -associated with touchpad events, and the third is associatd with trackstick -events. - -The first type is the touchpad position packet. - - byte 0: 1 ? x1 x0 1 1 1 1 - byte 1: 0 x10 x9 x8 x7 x6 x5 x4 - byte 2: 0 y10 y9 y8 y7 y6 y5 y4 - byte 3: 0 M R L 1 m r l - byte 4: 0 mt x3 x2 y3 y2 y1 y0 - byte 5: 0 z6 z5 z4 z3 z2 z1 z0 - -Note that for some devices the trackstick buttons are reported in this packet, -and on others it is reported in the trackstick packets. - -The second packet type contains bitmaps representing the x and y axes. In the -bitmaps a given bit is set if there is a finger covering that position on the -given axis. Thus the bitmap packet can be used for low-resolution multi-touch -data, although finger tracking is not possible. This packet also encodes the -number of contacts (f1 and f0 in the table below). - - byte 0: 1 1 x1 x0 1 1 1 1 - byte 1: 0 x8 x7 x6 x5 x4 x3 x2 - byte 2: 0 y7 y6 y5 y4 y3 y2 y1 - byte 3: 0 y10 y9 y8 1 1 1 1 - byte 4: 0 x14 x13 x12 x11 x10 x9 y0 - byte 5: 0 1 ? ? ? ? f1 f0 - -This packet only appears after a position packet with the mt bit set, and -usually only appears when there are two or more contacts (although -occassionally it's seen with only a single contact). - -The final v3 packet type is the trackstick packet. - - byte 0: 1 1 x7 y7 1 1 1 1 - byte 1: 0 x6 x5 x4 x3 x2 x1 x0 - byte 2: 0 y6 y5 y4 y3 y2 y1 y0 - byte 3: 0 1 0 0 1 0 0 0 - byte 4: 0 z4 z3 z2 z1 z0 ? ? - byte 5: 0 0 1 1 1 1 1 1 - -ALPS Absolute Mode - Protocol Version 4 ---------------------------------------- - -Protocol version 4 has an 8-byte packet format. - - byte 0: 1 ? x1 x0 1 1 1 1 - byte 1: 0 x10 x9 x8 x7 x6 x5 x4 - byte 2: 0 y10 y9 y8 y7 y6 y5 y4 - byte 3: 0 1 x3 x2 y3 y2 y1 y0 - byte 4: 0 ? ? ? 1 ? r l - byte 5: 0 z6 z5 z4 z3 z2 z1 z0 - byte 6: bitmap data (described below) - byte 7: bitmap data (described below) - -The last two bytes represent a partial bitmap packet, with 3 full packets -required to construct a complete bitmap packet. Once assembled, the 6-byte -bitmap packet has the following format: - - byte 0: 0 1 x7 x6 x5 x4 x3 x2 - byte 1: 0 x1 x0 y4 y3 y2 y1 y0 - byte 2: 0 0 ? x14 x13 x12 x11 x10 - byte 3: 0 x9 x8 y9 y8 y7 y6 y5 - byte 4: 0 0 0 0 0 0 0 0 - byte 5: 0 0 0 0 0 0 0 y10 - -There are several things worth noting here. - - 1) In the bitmap data, bit 6 of byte 0 serves as a sync byte to - identify the first fragment of a bitmap packet. - - 2) The bitmaps represent the same data as in the v3 bitmap packets, although - the packet layout is different. - - 3) There doesn't seem to be a count of the contact points anywhere in the v4 - protocol packets. Deriving a count of contact points must be done by - analyzing the bitmaps. - - 4) There is a 3 to 1 ratio of position packets to bitmap packets. Therefore - MT position can only be updated for every third ST position update, and - the count of contact points can only be updated every third packet as - well. - -So far no v4 devices with tracksticks have been encountered. |