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dt-bindings: gnss: u-blox: use open-drain reset and safeboot in example

PATCH Superseded Johan Hovold 1 participant 2 messages Nov 14, 2025

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Device tree bindings Gnss

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Johan Hovold

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#0 lore raw

PATCH 1/1 dt-bindings: gnss: u-blox: use open-drain reset and safeboot in example

The RESET_N and SAFEBOOT_N pins should typically be left open and only be connected to ground in rare cases where a device is misbehaving.

Switch to using GPIO_OPEN_DRAIN in the example as this is what should generally be used.

Note that the current Linux driver implementation depends on these pins being declared open-drain so that they are not driven while the main supply is off.

Signed-off-by Johan Hovold <[email protected]>
---
 Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml +2 -2
index 9f14cfe7efd1..e8b696986bb7 100644
@@ -67,7 +67,7 @@ examples:
             compatible = "u-blox,neo-8";
             v-bckp-supply = <&gnss_v_bckp_reg>;
             vcc-supply = <&gnss_vcc_reg>;
-            reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
-            safeboot-gpios = <&gpio 2 GPIO_ACTIVE_LOW>;
+            reset-gpios = <&gpio 1 GPIO_OPEN_DRAIN>;
+            safeboot-gpios = <&gpio 2 GPIO_OPEN_DRAIN>;
         };
     };
Signature · 1 line
2.51.0
author maintainer
#1 lore raw
Quoted 20 lines · Johan Hovold

The RESET_N and SAFEBOOT_N pins should typically be left open and only be connected to ground in rare cases where a device is misbehaving.

Switch to using GPIO_OPEN_DRAIN in the example as this is what should generally be used.

Note that the current Linux driver implementation depends on these pins being declared open-drain so that they are not driven while the main supply is off.

Signed-off-by Johan Hovold <[email protected]>
---
 Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml +0 -0
index 9f14cfe7efd1..e8b696986bb7 100644

Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml examples: · line 71

Quoted 7 lines
Documentation/devicetree/bindings/gnss/u-blox,neo-6m.yaml +2 -2
@@ -67,7 +67,7 @@ examples:
             compatible = "u-blox,neo-8";
             v-bckp-supply = <&gnss_v_bckp_reg>;
             vcc-supply = <&gnss_vcc_reg>;
-            reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
-            safeboot-gpios = <&gpio 2 GPIO_ACTIVE_LOW>;
+            reset-gpios = <&gpio 1 GPIO_OPEN_DRAIN>;
+            safeboot-gpios = <&gpio 2 GPIO_OPEN_DRAIN>;

Bah, I forgot about the ABI breakage introduced a few years ago which means that we now need to specify both open-drain and active-low:

	https://lore.kernel.org/all/20170719131640.GA2533@localhost/

Will fix in a v2.

Johan