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-rw-r--r--Documentation/input/rotary-encoder.txt9
-rw-r--r--Documentation/input/userio.txt70
2 files changed, 77 insertions, 2 deletions
diff --git a/Documentation/input/rotary-encoder.txt b/Documentation/input/rotary-encoder.txt
index 5737e3590..46a74f0c5 100644
--- a/Documentation/input/rotary-encoder.txt
+++ b/Documentation/input/rotary-encoder.txt
@@ -9,8 +9,9 @@ peripherals with two wires. The outputs are phase-shifted by 90 degrees
and by triggering on falling and rising edges, the turn direction can
be determined.
-Some encoders have both outputs low in stable states, whereas others also have
-a stable state with both outputs high (half-period mode).
+Some encoders have both outputs low in stable states, others also have
+a stable state with both outputs high (half-period mode) and some have
+a stable state in all steps (quarter-period mode).
The phase diagram of these two outputs look like this:
@@ -32,6 +33,9 @@ The phase diagram of these two outputs look like this:
|<-->|
one step (half-period mode)
+ |<>|
+ one step (quarter-period mode)
+
For more information, please see
https://en.wikipedia.org/wiki/Rotary_encoder
@@ -109,6 +113,7 @@ static struct rotary_encoder_platform_data my_rotary_encoder_info = {
.inverted_a = 0,
.inverted_b = 0,
.half_period = false,
+ .wakeup_source = false,
};
static struct platform_device rotary_encoder_device = {
diff --git a/Documentation/input/userio.txt b/Documentation/input/userio.txt
new file mode 100644
index 000000000..0880c0f44
--- /dev/null
+++ b/Documentation/input/userio.txt
@@ -0,0 +1,70 @@
+ The userio Protocol
+ (c) 2015 Stephen Chandler Paul <thatslyude@gmail.com>
+ Sponsored by Red Hat
+--------------------------------------------------------------------------------
+
+1. Introduction
+~~~~~~~~~~~~~~~
+ This module is intended to try to make the lives of input driver developers
+easier by allowing them to test various serio devices (mainly the various
+touchpads found on laptops) without having to have the physical device in front
+of them. userio accomplishes this by allowing any privileged userspace program
+to directly interact with the kernel's serio driver and control a virtual serio
+port from there.
+
+2. Usage overview
+~~~~~~~~~~~~~~~~~
+ In order to interact with the userio kernel module, one simply opens the
+/dev/userio character device in their applications. Commands are sent to the
+kernel module by writing to the device, and any data received from the serio
+driver is read as-is from the /dev/userio device. All of the structures and
+macros you need to interact with the device are defined in <linux/userio.h> and
+<linux/serio.h>.
+
+3. Command Structure
+~~~~~~~~~~~~~~~~~~~~
+ The struct used for sending commands to /dev/userio is as follows:
+
+ struct userio_cmd {
+ __u8 type;
+ __u8 data;
+ };
+
+ "type" describes the type of command that is being sent. This can be any one
+of the USERIO_CMD macros defined in <linux/userio.h>. "data" is the argument
+that goes along with the command. In the event that the command doesn't have an
+argument, this field can be left untouched and will be ignored by the kernel.
+Each command should be sent by writing the struct directly to the character
+device. In the event that the command you send is invalid, an error will be
+returned by the character device and a more descriptive error will be printed
+to the kernel log. Only one command can be sent at a time, any additional data
+written to the character device after the initial command will be ignored.
+ To close the virtual serio port, just close /dev/userio.
+
+4. Commands
+~~~~~~~~~~~
+
+4.1 USERIO_CMD_REGISTER
+~~~~~~~~~~~~~~~~~~~~~~~
+ Registers the port with the serio driver and begins transmitting data back and
+forth. Registration can only be performed once a port type is set with
+USERIO_CMD_SET_PORT_TYPE. Has no argument.
+
+4.2 USERIO_CMD_SET_PORT_TYPE
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ Sets the type of port we're emulating, where "data" is the port type being
+set. Can be any of the macros from <linux/serio.h>. For example: SERIO_8042
+would set the port type to be a normal PS/2 port.
+
+4.3 USERIO_CMD_SEND_INTERRUPT
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ Sends an interrupt through the virtual serio port to the serio driver, where
+"data" is the interrupt data being sent.
+
+5. Userspace tools
+~~~~~~~~~~~~~~~~~~
+ The userio userspace tools are able to record PS/2 devices using some of the
+debugging information from i8042, and play back the devices on /dev/userio. The
+latest version of these tools can be found at:
+
+ https://github.com/Lyude/ps2emu