From 1069032148f87dca8a5fce427271d324441c9dfe Mon Sep 17 00:00:00 2001
From: Ken Van Hoeylandt <git@kenvanhoeylandt.net>
Date: Tue, 14 Jul 2026 00:02:40 +0200
Subject: [PATCH] Improve gpio-hog driver

---
 Devices/lilygo-thmi/lilygo,thmi.dts           |  2 ++
 .../bindings/tactility,gpio-hog.yaml          | 10 ++++----
 .../include/tactility/drivers/gpio_hog.h      | 10 +++++---
 TactilityKernel/source/drivers/gpio_hog.cpp   | 23 ++++++++++++++++---
 4 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/Devices/lilygo-thmi/lilygo,thmi.dts b/Devices/lilygo-thmi/lilygo,thmi.dts
index 6ef4ac943..f17b24b8a 100644
--- a/Devices/lilygo-thmi/lilygo,thmi.dts
+++ b/Devices/lilygo-thmi/lilygo,thmi.dts
@@ -41,11 +41,13 @@
 	power_on {
 		compatible = "tactility,gpio-hog";
 		pin = <&gpio0 14 GPIO_FLAG_NONE>;
+		mode = <GPIO_HOG_MODE_OUTPUT_HIGH>;
 	};
 
 	power_en {
 		compatible = "tactility,gpio-hog";
 		pin = <&gpio0 10 GPIO_FLAG_NONE>;
+		mode = <GPIO_HOG_MODE_OUTPUT_HIGH>;
 	};
 
 	adc0 {
diff --git a/TactilityKernel/bindings/tactility,gpio-hog.yaml b/TactilityKernel/bindings/tactility,gpio-hog.yaml
index 19e0ec76a..1cd39f002 100644
--- a/TactilityKernel/bindings/tactility,gpio-hog.yaml
+++ b/TactilityKernel/bindings/tactility,gpio-hog.yaml
@@ -13,7 +13,9 @@ properties:
     type: phandles
     required: true
     description: The GPIO pin to hog
-  output-high:
-    type: boolean
-    default: true
-    description: Level to drive the pin to (true = high, false = low)
+  mode:
+    type: int
+    default: 0
+    description: |
+      Pin mode, see enum GpioHogMode in tactility/drivers/gpio_hog.h:
+      0 = GPIO_HOG_MODE_OUTPUT_HIGH, 1 = GPIO_HOG_MODE_OUTPUT_LOW, 2 = GPIO_HOG_MODE_INPUT.
diff --git a/TactilityKernel/include/tactility/drivers/gpio_hog.h b/TactilityKernel/include/tactility/drivers/gpio_hog.h
index 8ece049c5..6bb159aad 100644
--- a/TactilityKernel/include/tactility/drivers/gpio_hog.h
+++ b/TactilityKernel/include/tactility/drivers/gpio_hog.h
@@ -5,13 +5,17 @@
 extern "C" {
 #endif
 
-#include <stdbool.h>
-
 #include <tactility/drivers/gpio.h>
 
+enum GpioHogMode {
+    GPIO_HOG_MODE_OUTPUT_HIGH,
+    GPIO_HOG_MODE_OUTPUT_LOW,
+    GPIO_HOG_MODE_INPUT,
+};
+
 struct GpioHogConfig {
     struct GpioPinSpec pin;
-    bool output_high;
+    enum GpioHogMode mode;
 };
 
 #ifdef __cplusplus
diff --git a/TactilityKernel/source/drivers/gpio_hog.cpp b/TactilityKernel/source/drivers/gpio_hog.cpp
index 28b15ca01..d3f08cab0 100644
--- a/TactilityKernel/source/drivers/gpio_hog.cpp
+++ b/TactilityKernel/source/drivers/gpio_hog.cpp
@@ -24,9 +24,26 @@ static error_t start(Device* device) {
         return ERROR_RESOURCE;
     }
 
-    if (gpio_descriptor_set_flags(descriptor, GPIO_FLAG_DIRECTION_OUTPUT) != ERROR_NONE ||
-        gpio_descriptor_set_level(descriptor, config->output_high) != ERROR_NONE) {
-        LOG_E(TAG, "Failed to configure hogged pin");
+    bool ok;
+    switch (config->mode) {
+        case GPIO_HOG_MODE_OUTPUT_HIGH:
+            ok = gpio_descriptor_set_flags(descriptor, GPIO_FLAG_DIRECTION_OUTPUT) == ERROR_NONE &&
+                gpio_descriptor_set_level(descriptor, true) == ERROR_NONE;
+            break;
+        case GPIO_HOG_MODE_OUTPUT_LOW:
+            ok = gpio_descriptor_set_flags(descriptor, GPIO_FLAG_DIRECTION_OUTPUT) == ERROR_NONE &&
+                gpio_descriptor_set_level(descriptor, false) == ERROR_NONE;
+            break;
+        case GPIO_HOG_MODE_INPUT:
+            ok = gpio_descriptor_set_flags(descriptor, GPIO_FLAG_DIRECTION_INPUT) == ERROR_NONE;
+            break;
+        default:
+            ok = false;
+            break;
+    }
+
+    if (!ok) {
+        LOG_E(TAG, "Failed to configure hogged pin %u", config->pin.pin);
         gpio_descriptor_release(descriptor);
         return ERROR_RESOURCE;
     }