From: Angela Czubak <aczubak@google.com>

INPUT_PROP_HAPTIC_TOUCHPAD property is to be set for a device with simple
haptic capabilities.

Signed-off-by: Angela Czubak <aczubak@google.com>
Co-developed-by: Jonathan Denose <jdenose@google.com>
Signed-off-by: Jonathan Denose <jdenose@google.com>
---
 Documentation/input/event-codes.rst    | 14 ++++++++++++++
 include/uapi/linux/input-event-codes.h |  1 +
 2 files changed, 15 insertions(+)

diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst
index b4557462edd7b3fef9e9cd6c2c3cb2d05bb531ab..6f7aa9e8207c4aa825d9694ad891f4d105fe8196 100644
--- a/Documentation/input/event-codes.rst
+++ b/Documentation/input/event-codes.rst
@@ -400,6 +400,20 @@ can report through the rotational axes (absolute and/or relative rx, ry, rz).
 All other axes retain their meaning. A device must not mix
 regular directional axes and accelerometer axes on the same event node.
 
+INPUT_PROP_HAPTIC_TOUCHPAD
+--------------------------
+
+The INPUT_PROP_HAPTIC_TOUCHPAD property indicates that device:
+- supports simple haptic auto and manual triggering
+- can differentiate between at least 5 fingers
+- uses correct resolution for the X/Y (units and value)
+- report correct force per touch, and correct units for them (newtons or grams)
+- follows the MT protocol type B
+
+Summing up, such devices follow the MS spec for input devices in
+Win8 and Win8.1, and in addition support the Simple haptic controller HID table,
+and report correct units for the pressure.
+
 Guidelines
 ==========
 
diff --git a/include/uapi/linux/input-event-codes.h b/include/uapi/linux/input-event-codes.h
index 3b2524e4b667d1e7cc02ff5cb674e7c2ac069a66..efe8c36d4ee9a938ffb1b0dd0ddd0ec6a3fcb8fe 100644
--- a/include/uapi/linux/input-event-codes.h
+++ b/include/uapi/linux/input-event-codes.h
@@ -27,6 +27,7 @@
 #define INPUT_PROP_TOPBUTTONPAD		0x04	/* softbuttons at top of pad */
 #define INPUT_PROP_POINTING_STICK	0x05	/* is a pointing stick */
 #define INPUT_PROP_ACCELEROMETER	0x06	/* has accelerometer */
+#define INPUT_PROP_HAPTIC_TOUCHPAD	0x07	/* is a haptic touchpad */
 
 #define INPUT_PROP_MAX			0x1f
 #define INPUT_PROP_CNT			(INPUT_PROP_MAX + 1)

-- 
2.51.0.rc1.163.g2494970778-goog

On 8/18/25 7:28 AM, Jonathan Denose wrote:
> From: Angela Czubak <aczubak@google.com>
> 
> INPUT_PROP_HAPTIC_TOUCHPAD property is to be set for a device with simple
> haptic capabilities.
> 
> Signed-off-by: Angela Czubak <aczubak@google.com>
> Co-developed-by: Jonathan Denose <jdenose@google.com>
> Signed-off-by: Jonathan Denose <jdenose@google.com>
> ---
>  Documentation/input/event-codes.rst    | 14 ++++++++++++++
>  include/uapi/linux/input-event-codes.h |  1 +
>  2 files changed, 15 insertions(+)
> 
> diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst
> index b4557462edd7b3fef9e9cd6c2c3cb2d05bb531ab..6f7aa9e8207c4aa825d9694ad891f4d105fe8196 100644
> --- a/Documentation/input/event-codes.rst
> +++ b/Documentation/input/event-codes.rst
> @@ -400,6 +400,20 @@ can report through the rotational axes (absolute and/or relative rx, ry, rz).
>  All other axes retain their meaning. A device must not mix
>  regular directional axes and accelerometer axes on the same event node.
>  
> +INPUT_PROP_HAPTIC_TOUCHPAD
> +--------------------------
> +
> +The INPUT_PROP_HAPTIC_TOUCHPAD property indicates that device:
> +- supports simple haptic auto and manual triggering
> +- can differentiate between at least 5 fingers
> +- uses correct resolution for the X/Y (units and value)
> +- report correct force per touch, and correct units for them (newtons or grams)

     reports

> +- follows the MT protocol type B
> +
> +Summing up, such devices follow the MS spec for input devices in


-- 
~Randy