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authorLinus Torvalds <torvalds@linux-foundation.org>2013-03-11 10:49:37 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-03-11 10:49:37 -0400
commit152fcb2784c9305e19e7caee2932b9e32b0a1d41 (patch)
treea8fceed3656ea2e7ef6a3c2f5afb450cf7620bdd /Documentation/input
parentf6161aa153581da4a3867a2d1a7caf4be19b6ec9 (diff)
parent4b7d293c64fde133cc2b669d0d7637b8a4c6d62f (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov: "Except for the largish change to the ALPS driver adding "Dolphin V1" support and Wacom getting a new signature of yet another device, the rest are straightforward driver fixes." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: mms114 - Fix regulator enable and disable paths Input: ads7864 - check return value of regulator enable Input: tc3589x-keypad - fix keymap size Input: wacom - add support for 0x10d Input: ALPS - update documentation for recent touchpad driver mods Input: ALPS - add "Dolphin V1" touchpad support Input: ALPS - remove unused argument to alps_enter_command_mode() Input: cypress_ps2 - fix trackpadi found in Dell XPS12
Diffstat (limited to 'Documentation/input')
-rw-r--r--Documentation/input/alps.txt67
1 files changed, 60 insertions, 7 deletions
diff --git a/Documentation/input/alps.txt b/Documentation/input/alps.txt
index 3262b6e4d686..e544c7ff8cfa 100644
--- a/Documentation/input/alps.txt
+++ b/Documentation/input/alps.txt
@@ -3,10 +3,26 @@ ALPS Touchpad Protocol
3 3
4Introduction 4Introduction
5------------ 5------------
6 6Currently the ALPS touchpad driver supports five protocol versions in use by
7Currently the ALPS touchpad driver supports four protocol versions in use by 7ALPS touchpads, called versions 1, 2, 3, 4 and 5.
8ALPS touchpads, called versions 1, 2, 3, and 4. Information about the various 8
9protocol versions is contained in the following sections. 9Since roughly mid-2010 several new ALPS touchpads have been released and
10integrated into a variety of laptops and netbooks. These new touchpads
11have enough behavior differences that the alps_model_data definition
12table, describing the properties of the different versions, is no longer
13adequate. The design choices were to re-define the alps_model_data
14table, with the risk of regression testing existing devices, or isolate
15the new devices outside of the alps_model_data table. The latter design
16choice was made. The new touchpad signatures are named: "Rushmore",
17"Pinnacle", and "Dolphin", which you will see in the alps.c code.
18For the purposes of this document, this group of ALPS touchpads will
19generically be called "new ALPS touchpads".
20
21We experimented with probing the ACPI interface _HID (Hardware ID)/_CID
22(Compatibility ID) definition as a way to uniquely identify the
23different ALPS variants but there did not appear to be a 1:1 mapping.
24In fact, it appeared to be an m:n mapping between the _HID and actual
25hardware type.
10 26
11Detection 27Detection
12--------- 28---------
@@ -20,9 +36,13 @@ If the E6 report is successful, the touchpad model is identified using the "E7
20report" sequence: E8-E7-E7-E7-E9. The response is the model signature and is 36report" sequence: E8-E7-E7-E7-E9. The response is the model signature and is
21matched against known models in the alps_model_data_array. 37matched against known models in the alps_model_data_array.
22 38
23With protocol versions 3 and 4, the E7 report model signature is always 39For older touchpads supporting protocol versions 3 and 4, the E7 report
2473-02-64. To differentiate between these versions, the response from the 40model signature is always 73-02-64. To differentiate between these
25"Enter Command Mode" sequence must be inspected as described below. 41versions, the response from the "Enter Command Mode" sequence must be
42inspected as described below.
43
44The new ALPS touchpads have an E7 signature of 73-03-50 or 73-03-0A but
45seem to be better differentiated by the EC Command Mode response.
26 46
27Command Mode 47Command Mode
28------------ 48------------
@@ -47,6 +67,14 @@ address of the register being read, and the third contains the value of the
47register. Registers are written by writing the value one nibble at a time 67register. Registers are written by writing the value one nibble at a time
48using the same encoding used for addresses. 68using the same encoding used for addresses.
49 69
70For the new ALPS touchpads, the EC command is used to enter command
71mode. The response in the new ALPS touchpads is significantly different,
72and more important in determining the behavior. This code has been
73separated from the original alps_model_data table and put in the
74alps_identify function. For example, there seem to be two hardware init
75sequences for the "Dolphin" touchpads as determined by the second byte
76of the EC response.
77
50Packet Format 78Packet Format
51------------- 79-------------
52 80
@@ -187,3 +215,28 @@ There are several things worth noting here.
187 well. 215 well.
188 216
189So far no v4 devices with tracksticks have been encountered. 217So far no v4 devices with tracksticks have been encountered.
218
219ALPS Absolute Mode - Protocol Version 5
220---------------------------------------
221This is basically Protocol Version 3 but with different logic for packet
222decode. It uses the same alps_process_touchpad_packet_v3 call with a
223specialized decode_fields function pointer to correctly interpret the
224packets. This appears to only be used by the Dolphin devices.
225
226For single-touch, the 6-byte packet format is:
227
228 byte 0: 1 1 0 0 1 0 0 0
229 byte 1: 0 x6 x5 x4 x3 x2 x1 x0
230 byte 2: 0 y6 y5 y4 y3 y2 y1 y0
231 byte 3: 0 M R L 1 m r l
232 byte 4: y10 y9 y8 y7 x10 x9 x8 x7
233 byte 5: 0 z6 z5 z4 z3 z2 z1 z0
234
235For mt, the format is:
236
237 byte 0: 1 1 1 n3 1 n2 n1 x24
238 byte 1: 1 y7 y6 y5 y4 y3 y2 y1
239 byte 2: ? x2 x1 y12 y11 y10 y9 y8
240 byte 3: 0 x23 x22 x21 x20 x19 x18 x17
241 byte 4: 0 x9 x8 x7 x6 x5 x4 x3
242 byte 5: 0 x16 x15 x14 x13 x12 x11 x10