1 files changed, 60 insertions, 7 deletions

diff --git a/Documentation/input/alps.txt b/Documentation/input/alps.txt
index ae8ba9a74ce1..9b1084c8c0b3 100644
--- a/Documentation/input/alps.txt
+++ b/Documentation/input/alps.txt
@@ -3,10 +3,26 @@ 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.
+Currently the ALPS touchpad driver supports five protocol versions in use by
+ALPS touchpads, called versions 1, 2, 3, 4 and 5.
+
+Since roughly mid-2010 several new ALPS touchpads have been released and
+integrated into a variety of laptops and netbooks.  These new touchpads
+have enough behavior differences that the alps_model_data definition
+table, describing the properties of the different versions, is no longer
+adequate.  The design choices were to re-define the alps_model_data
+table, with the risk of regression testing existing devices, or isolate
+the new devices outside of the alps_model_data table.  The latter design
+choice was made.  The new touchpad signatures are named: "Rushmore",
+"Pinnacle", and "Dolphin", which you will see in the alps.c code.
+For the purposes of this document, this group of ALPS touchpads will
+generically be called "new ALPS touchpads".
+
+We experimented with probing the ACPI interface _HID (Hardware ID)/_CID
+(Compatibility ID) definition as a way to uniquely identify the
+different ALPS variants but there did not appear to be a 1:1 mapping.
+In fact, it appeared to be an m:n mapping between the _HID and actual
+hardware type.
 
 Detection
 ---------
@@ -20,9 +36,13 @@ 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.
+For older touchpads supporting 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.
+
+The new ALPS touchpads have an E7 signature of 73-03-50 or 73-03-0A but
+seem to be better differentiated by the EC Command Mode response.
 
 Command Mode
 ------------
@@ -47,6 +67,14 @@ 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.
 
+For the new ALPS touchpads, the EC command is used to enter command
+mode. The response in the new ALPS touchpads is significantly different,
+and more important in determining the behavior.  This code has been
+separated from the original alps_model_data table and put in the
+alps_identify function.  For example, there seem to be two hardware init
+sequences for the "Dolphin" touchpads as determined by the second byte
+of the EC response.
+
 Packet Format
 -------------
 
@@ -187,3 +215,28 @@ There are several things worth noting here.
     well.
 
 So far no v4 devices with tracksticks have been encountered.
+
+ALPS Absolute Mode - Protocol Version 5
+---------------------------------------
+This is basically Protocol Version 3 but with different logic for packet
+decode.  It uses the same alps_process_touchpad_packet_v3 call with a
+specialized decode_fields function pointer to correctly interpret the
+packets.  This appears to only be used by the Dolphin devices.
+
+For single-touch, the 6-byte packet format is:
+
+ byte 0:    1    1    0    0    1    0    0    0
+ byte 1:    0   x6   x5   x4   x3   x2   x1   x0
+ byte 2:    0   y6   y5   y4   y3   y2   y1   y0
+ byte 3:    0    M    R    L    1    m    r    l
+ byte 4:   y10  y9   y8   y7  x10   x9   x8   x7
+ byte 5:    0   z6   z5   z4   z3   z2   z1   z0
+
+For mt, the format is:
+
+ byte 0:    1    1    1    n3   1   n2   n1   x24
+ byte 1:    1   y7   y6    y5  y4   y3   y2    y1
+ byte 2:    ?   x2   x1   y12 y11  y10   y9    y8
+ byte 3:    0  x23  x22   x21 x20  x19  x18   x17
+ byte 4:    0   x9   x8    x7  x6   x5   x4    x3
+ byte 5:    0  x16  x15   x14 x13  x12  x11   x10