keyboard: update the scan period properties

Scan period properties are now in us, update our files and
documentation.

BUG=none
TEST=cq dry run

Cq-Depend: chromium:7747223
Change-Id: If5137e1f979eba2a4abdf1f89bc221d3f74936b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/7692815
Tested-by: Fabio Baltieri <fabiobaltieri@google.com>
Commit-Queue: Fabio Baltieri <fabiobaltieri@google.com>
Reviewed-by: Rob Barnes <robbarnes@google.com>
diff --git a/docs/zephyr/zephyr_keyboard.md b/docs/zephyr/zephyr_keyboard.md
index a4603b5..854801a 100644
--- a/docs/zephyr/zephyr_keyboard.md
+++ b/docs/zephyr/zephyr_keyboard.md
@@ -51,7 +51,8 @@
 
 Property | Description | Settings
 :------- | :---------- | :-------
-`poll-period-ms` |  Defines the poll period in milliseconds between between matrix scans. | `int` (default 5)
+`poll-period-us` |  Defines the poll period in microseconds between between matrix scans. | `int` (default 5000)
+`stable-poll-period-us` |  Defines the poll period in microseconds between between matrix scans when the matrix is stable. | `int` (default not set)
 `poll-timeout-ms` | How long to wait before going from polling back to idle state. | `int` (default 100)
 `debounce-down-ms` | Debouncing time for a key press event. | `int` (default 10)
 `debounce-up-ms` | Debouncing time for a key release event. | `int` (default 20)
diff --git a/zephyr/boards/google/it8xxx2/it8xxx2.dtsi b/zephyr/boards/google/it8xxx2/it8xxx2.dtsi
index 0e44589..e5d23a2 100644
--- a/zephyr/boards/google/it8xxx2/it8xxx2.dtsi
+++ b/zephyr/boards/google/it8xxx2/it8xxx2.dtsi
@@ -40,6 +40,6 @@
 	actual-key-mask = <0x1c 0xff 0xff 0xff 0xff
 			   0xf5 0xff 0xa4 0xff 0xfe
 			   0x55 0xfa 0xca>;
-	poll-period-ms = <3>;
-	stable-poll-period-ms = <9>;
+	poll-period-us = <3000>;
+	stable-poll-period-us = <9000>;
 };
diff --git a/zephyr/boards/google/npcx9/npcx9.dtsi b/zephyr/boards/google/npcx9/npcx9.dtsi
index 15bfcee..a6ba684 100644
--- a/zephyr/boards/google/npcx9/npcx9.dtsi
+++ b/zephyr/boards/google/npcx9/npcx9.dtsi
@@ -172,6 +172,6 @@
 	actual-key-mask = <0x1c 0xff 0xff 0xff 0xff
 			   0xf5 0xff 0xa4 0xff 0xfe
 			   0x55 0xfa 0xca>;
-	poll-period-ms = <3>;
-	stable-poll-period-ms = <9>;
+	poll-period-us = <3000>;
+	stable-poll-period-us = <9000>;
 };