[PATCH v6 2/2] dt-bindings: cros-ec: Add ChromeOS fingerprint binding

From: Stephen Boyd
Date: Tue Jun 14 2022 - 15:51:59 EST


Add a binding to describe the fingerprint processor found on Chromebooks
with a fingerprint sensor. Previously we've been describing this with
the google,cros-ec-spi binding but it lacks gpio and regulator control
used during firmware flashing.

Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>
Cc: <devicetree@xxxxxxxxxxxxxxx>
Cc: <chrome-platform@xxxxxxxxxxxxxxx>
Cc: Guenter Roeck <groeck@xxxxxxxxxxxx>
Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
Cc: Craig Hesling <hesling@xxxxxxxxxxxx>
Cc: Tom Hughes <tomhughes@xxxxxxxxxxxx>
Cc: Alexandru M Stan <amstan@xxxxxxxxxxxx>
Cc: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
Cc: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Cc: Benson Leung <bleung@xxxxxxxxxxxx>
Cc: Lee Jones <lee.jones@xxxxxxxxxx>
Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
---
.../bindings/chrome/google,cros-ec-fp.yaml | 97 +++++++++++++++++++
.../bindings/mfd/google,cros-ec.yaml | 9 ++
2 files changed, 106 insertions(+)
create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml

diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
new file mode 100644
index 000000000000..48c02bd4585c
--- /dev/null
+++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
@@ -0,0 +1,97 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/chrome/google,cros-ec-fp.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ChromeOS Embedded Fingerprint Controller
+
+description:
+ Google's ChromeOS embedded fingerprint controller is a device which
+ implements fingerprint functionality such as unlocking a Chromebook
+ without typing a password.
+
+maintainers:
+ - Tom Hughes <tomhughes@xxxxxxxxxxxx>
+
+select:
+ properties:
+ compatible:
+ contains:
+ const: google,cros-ec-spi
+ required:
+ - compatible
+ - boot0-gpios
+
+allOf:
+ - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+ compatible:
+ items:
+ - const: google,cros-ec-fp
+ - const: google,cros-ec-spi
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ controller-data: true
+
+ google,cros-ec-spi-pre-delay:
+ description:
+ This property specifies the delay in usecs between the
+ assertion of the CS and the first clock pulse.
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 0
+
+ google,cros-ec-spi-msg-delay:
+ description:
+ This property specifies the delay in usecs between messages.
+ $ref: /schemas/types.yaml#/definitions/uint32
+ default: 0
+
+ spi-max-frequency:
+ maximum: 3000000
+
+ reset-gpios:
+ maxItems: 1
+
+ boot0-gpios:
+ maxItems: 1
+ description: Assert for bootloader mode.
+
+ vdd-supply: true
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - reset-gpios
+ - boot0-gpios
+ - vdd-supply
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ #include <dt-bindings/gpio/gpio.h>
+ spi0 {
+ #address-cells = <0x1>;
+ #size-cells = <0x0>;
+
+ ec@0 {
+ compatible = "google,cros-ec-fp", "google,cros-ec-spi";
+ reg = <0x0>;
+ interrupt-parent = <&gpio_controller>;
+ interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
+ spi-max-frequency = <3000000>;
+ reset-gpios = <&gpio_controller 5 GPIO_ACTIVE_LOW>;
+ boot0-gpios = <&gpio_controller 10 GPIO_ACTIVE_HIGH>;
+ vdd-supply = <&pp3300_fp_mcu>;
+ };
+ };
+...
diff --git a/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml b/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml
index 178e26ab115c..a7453bbd7bed 100644
--- a/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml
+++ b/Documentation/devicetree/bindings/mfd/google,cros-ec.yaml
@@ -10,6 +10,15 @@ maintainers:
- Benson Leung <bleung@xxxxxxxxxxxx>
- Guenter Roeck <groeck@xxxxxxxxxxxx>

+select:
+ properties:
+ compatible:
+ contains:
+ const: google,cros-ec-spi
+ boot0-gpios: false
+ required:
+ - compatible
+
description:
Google's ChromeOS EC is a microcontroller which talks to the AP and
implements various functions such as keyboard and battery charging.
--
https://chromeos.dev