[PATCH v2 1/3] dt-bindings: input: atmel_mxt_ts: Document atmel,wakeup-method and wake-GPIO

Dmitry Osipenko
2020-12-05T05:48:59Z

Some Atmel touchscreen controllers have a WAKE line that needs to be
asserted low in order to wake up controller from a deep sleep. Document
the wakeup methods and the wake-GPIO properties.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
.../bindings/input/atmel,maxtouch.yaml | 26 +++++++++++++++++++
include/dt-bindings/input/atmel-maxtouch.h | 10 +++++++
2 files changed, 36 insertions(+)
create mode 100644 include/dt-bindings/input/atmel-maxtouch.h

diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml b/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml
index 8c6418f76e94..7924a16dc248 100644
--- a/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml
+++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.yaml
@@ -39,6 +39,13 @@ properties:
(active low). The line must be flagged with
GPIO_ACTIVE_LOW.

+ wake-gpios:
+ maxItems: 1
+ description:
+ Optional GPIO specifier for the touchscreen's wake pin
+ (active low). The line must be flagged with
+ GPIO_ACTIVE_LOW.
+
linux,gpio-keymap:
$ref: /schemas/types.yaml#/definitions/uint32-array
description: |
@@ -53,6 +60,23 @@ properties:
or experiment to determine which bit corresponds to which input. Use
KEY_RESERVED for unused padding values.

+ atmel,wakeup-method:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ The WAKE line is an active-low input that is used to wake up the touch
+ controller from deep-sleep mode before communication with the controller
+ could be started. This feature used to minimize current consumption
+ when the controller is in deep sleep mode.
+
+ The WAKE pin can be connected in one of the following ways:
+ 1) left permanently low
+ 2) connected to the I2C-compatible SCL pin
+ 3) connected to a GPIO pin on the host
+ enum:
+ - 0 # ATMEL_MXT_WAKEUP_NONE
+ - 1 # ATMEL_MXT_WAKEUP_I2C_SCL
+ - 2 # ATMEL_MXT_WAKEUP_GPIO
+
required:
- compatible
- reg
@@ -63,6 +87,7 @@ additionalProperties: false
examples:
- |
#include <dt-bindings/interrupt-controller/irq.h>
+ #include <dt-bindings/input/atmel-maxtouch.h>
#include <dt-bindings/gpio/gpio.h>
i2c {
#address-cells = <1>;
@@ -75,6 +100,7 @@ examples:
reset-gpios = <&gpio 27 GPIO_ACTIVE_LOW>;
vdda-supply = <&ab8500_ldo_aux2_reg>;
vdd-supply = <&ab8500_ldo_aux5_reg>;
+ atmel,wakeup-method = <ATMEL_MXT_WAKEUP_I2C_SCL>;
};
};

diff --git a/include/dt-bindings/input/atmel-maxtouch.h b/include/dt-bindings/input/atmel-maxtouch.h
new file mode 100644
index 000000000000..7345ab32224d
--- /dev/null
+++ b/include/dt-bindings/input/atmel-maxtouch.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _DT_BINDINGS_ATMEL_MAXTOUCH_H
+#define _DT_BINDINGS_ATMEL_MAXTOUCH_H
+
+#define ATMEL_MXT_WAKEUP_NONE 0
+#define ATMEL_MXT_WAKEUP_I2C_SCL 1
+#define ATMEL_MXT_WAKEUP_GPIO 2
+
+#endif /* _DT_BINDINGS_ATMEL_MAXTOUCH_H */
--
2.29.2