From b6b129650af37b6c67f980e6d9d36b78e45a0c2c Mon Sep 17 00:00:00 2001
From: Jonathan Bennett <jbennett@incomsystems.biz>
Date: Sun, 11 Jan 2026 18:27:06 -0600
Subject: [PATCH] Extra pins (#9260)

* Maybe add working extra GPIO pins to portduino

* Fix typo and add config.yaml example for ExtraPins

* Write extra pins back out with -y flag
---
 bin/config-dist.yaml                     |  2 ++
 src/platform/portduino/PortduinoGlue.cpp | 28 ++++++++++++++++++++++++
 src/platform/portduino/PortduinoGlue.h   | 16 ++++++++++++++
 3 files changed, 46 insertions(+)

diff --git a/bin/config-dist.yaml b/bin/config-dist.yaml
index adf804ba9..3c996051e 100644
--- a/bin/config-dist.yaml
+++ b/bin/config-dist.yaml
@@ -105,6 +105,8 @@ Lora:
 
 GPS:
 #  SerialPath: /dev/ttyS0
+#  ExtraPins:
+#    - 22
 
 ### Specify I2C device, or leave blank for none
 
diff --git a/src/platform/portduino/PortduinoGlue.cpp b/src/platform/portduino/PortduinoGlue.cpp
index af7e275c6..7430c2eae 100644
--- a/src/platform/portduino/PortduinoGlue.cpp
+++ b/src/platform/portduino/PortduinoGlue.cpp
@@ -487,6 +487,11 @@ void portduinoSetup()
             max_GPIO = i->pin;
     }
 
+    for (auto i : portduino_config.extra_pins) {
+        if (i.enabled && i.pin > max_GPIO)
+            max_GPIO = i.pin;
+    }
+
     gpioInit(max_GPIO + 1); // Done here so we can inform Portduino how many GPIOs we need.
 
     // Need to bind all the configured GPIO pins so they're not simulated
@@ -504,6 +509,19 @@ void portduinoSetup()
             }
         }
     }
+    for (auto i : portduino_config.extra_pins) {
+        // In the case of a ch341 Lora device, we don't want to touch the system GPIO lines for Lora
+        // Those GPIO are handled in our usermode driver instead.
+        if (i.config_section == "Lora" && portduino_config.lora_spi_dev == "ch341") {
+            continue;
+        }
+        if (i.enabled) {
+            if (initGPIOPin(i.pin, gpioChipName + std::to_string(i.gpiochip), i.line) != ERRNO_OK) {
+                printf("Error setting pin number %d. It may not exist, or may already be in use.\n", i.line);
+                exit(EXIT_FAILURE);
+            }
+        }
+    }
 
     // Only initialize the radio pins when dealing with real, kernel controlled SPI hardware
     if (portduino_config.lora_spi_dev != "" && portduino_config.lora_spi_dev != "ch341") {
@@ -717,6 +735,16 @@ bool loadConfig(const char *configPath)
                 portduino_config.has_gps = 1;
             }
         }
+        if (yamlConfig["GPIO"]["ExtraPins"]) {
+            for (auto extra_pin : yamlConfig["GPIO"]["ExtraPins"]) {
+                portduino_config.extra_pins.push_back(pinMapping());
+                portduino_config.extra_pins.back().config_section = "GPIO";
+                portduino_config.extra_pins.back().config_name = "ExtraPins";
+                portduino_config.extra_pins.back().enabled = true;
+                readGPIOFromYaml(extra_pin, portduino_config.extra_pins.back());
+            }
+        }
+
         if (yamlConfig["I2C"]) {
             portduino_config.i2cdev = yamlConfig["I2C"]["I2CDevice"].as<std::string>("");
         }
diff --git a/src/platform/portduino/PortduinoGlue.h b/src/platform/portduino/PortduinoGlue.h
index 9335be90a..8992f5f1a 100644
--- a/src/platform/portduino/PortduinoGlue.h
+++ b/src/platform/portduino/PortduinoGlue.h
@@ -2,6 +2,7 @@
 #include <fstream>
 #include <map>
 #include <unordered_map>
+#include <vector>
 
 #include "LR11x0Interface.h"
 #include "Module.h"
@@ -97,6 +98,7 @@ extern struct portduino_config_struct {
     pinMapping lora_txen_pin = {"Lora", "TXen"};
     pinMapping lora_rxen_pin = {"Lora", "RXen"};
     pinMapping lora_sx126x_ant_sw_pin = {"Lora", "SX126X_ANT_SW"};
+    std::vector<pinMapping> extra_pins = {};
 
     // GPS
     bool has_gps = false;
@@ -300,6 +302,20 @@ extern struct portduino_config_struct {
         }
         out << YAML::EndMap; // Lora
 
+        if (!extra_pins.empty()) {
+            out << YAML::Key << "GPIO" << YAML::Value << YAML::BeginMap;
+            out << YAML::Key << "ExtraPins" << YAML::Value << YAML::BeginSeq;
+            for (auto extra : extra_pins) {
+                out << YAML::BeginMap;
+                out << YAML::Key << "pin" << YAML::Value << extra.pin;
+                out << YAML::Key << "line" << YAML::Value << extra.line;
+                out << YAML::Key << "gpiochip" << YAML::Value << extra.gpiochip;
+                out << YAML::EndMap;
+            }
+            out << YAML::EndSeq;
+            out << YAML::EndMap; // GPIO
+        }
+
         if (i2cdev != "") {
             out << YAML::Key << "I2C" << YAML::Value << YAML::BeginMap;
             out << YAML::Key << "I2CDevice" << YAML::Value << i2cdev;