[PATCH 2/3] dt-bindings: iio: magnetometer: ak8975: add gpio reset support

From: Jonathan Albrieux
Date: Mon May 18 2020 - 09:37:24 EST


Add reset-gpio support.

AK09911 has a reset gpio to handle register's reset. If reset gpio is
set to low it will trigger the reset. AK09911 datasheed says that if not
used reset pin should be connected to VID and this patch emulates this
situation

Without setting it to high on ak8975_power_on driver's probe fails
on ak8975_who_i_am while checking for device identity for AK09911 chip

Signed-off-by: Jonathan Albrieux <jonathan.albrieux@xxxxxxxxx>
---
.../devicetree/bindings/iio/magnetometer/ak8975.yaml | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/magnetometer/ak8975.yaml b/Documentation/devicetree/bindings/iio/magnetometer/ak8975.yaml
index 86e3efa693a8..a82c0ff5d098 100644
--- a/Documentation/devicetree/bindings/iio/magnetometer/ak8975.yaml
+++ b/Documentation/devicetree/bindings/iio/magnetometer/ak8975.yaml
@@ -37,6 +37,9 @@ properties:
mount-matrix:
description: an optional 3x3 mounting rotation matrix

+ reset-gpio:
+ description: an optional pin needed for AK09911 to set the reset state
+
required:
- compatible
- reg
@@ -53,6 +56,7 @@ examples:
reg = <0x0c>;
gpios = <&gpj0 7 0>;
vdd-supply = <&ldo_3v3_gnss>;
+ reset-gpio = <&msmgpio 111 1>;
mount-matrix = "-0.984807753012208", /* x0 */
"0", /* y0 */
"-0.173648177666930", /* z0 */
--
2.17.1