From 43a2f20ea7afaf7eb3fe588019d0e0327922ce4a Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Sun, 14 Sep 2025 22:18:44 -0500
Subject: [PATCH] [json] Only compile SpiRamAllocator when PSRAM is enabled

---
 esphome/components/json/json_util.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/esphome/components/json/json_util.cpp b/esphome/components/json/json_util.cpp
index 94c531222a..842b5e283a 100644
--- a/esphome/components/json/json_util.cpp
+++ b/esphome/components/json/json_util.cpp
@@ -8,7 +8,9 @@ namespace json {
 
 static const char *const TAG = "json";
 
+#ifdef USE_PSRAM
 // Build an allocator for the JSON Library using the RAMAllocator class
+// This is only compiled when PSRAM is enabled
 struct SpiRamAllocator : ArduinoJson::Allocator {
   void *allocate(size_t size) override { return this->allocator_.allocate(size); }
 
@@ -29,11 +31,16 @@ struct SpiRamAllocator : ArduinoJson::Allocator {
  protected:
   RAMAllocator<uint8_t> allocator_{RAMAllocator<uint8_t>(RAMAllocator<uint8_t>::NONE)};
 };
+#endif
 
 std::string build_json(const json_build_t &f) {
   // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+#ifdef USE_PSRAM
   auto doc_allocator = SpiRamAllocator();
   JsonDocument json_document(&doc_allocator);
+#else
+  JsonDocument json_document;
+#endif
   if (json_document.overflowed()) {
     ESP_LOGE(TAG, "Could not allocate memory for JSON document!");
     return "{}";
@@ -52,8 +59,12 @@ std::string build_json(const json_build_t &f) {
 
 bool parse_json(const std::string &data, const json_parse_t &f) {
   // NOLINTBEGIN(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
+#ifdef USE_PSRAM
   auto doc_allocator = SpiRamAllocator();
   JsonDocument json_document(&doc_allocator);
+#else
+  JsonDocument json_document;
+#endif
   if (json_document.overflowed()) {
     ESP_LOGE(TAG, "Could not allocate memory for JSON document!");
     return false;