From e6f96ea0e38ad97310a91f9be313433614479593 Mon Sep 17 00:00:00 2001
From: crosstyan <crosstyan@outlook.com>
Date: Thu, 11 Jun 2026 18:25:22 +0800
Subject: [PATCH] fix(llcc68): cache detected chip type

Store the detected chip type after the first successful version-register read so repeated radio operations do not keep querying the chip identity.

This preserves Unknown as uncached so transient read failures or unsupported responses can still be retried on a later call.
---
 include/llcc68.hpp |  1 +
 src/llcc68.cpp     | 21 ++++++++++++++-------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/include/llcc68.hpp b/include/llcc68.hpp
index f98d24e..25d7047 100644
--- a/include/llcc68.hpp
+++ b/include/llcc68.hpp
@@ -303,6 +303,7 @@ struct LLCC68 {
 
 	/** properties */
 	const struct device *dev;
+	std::optional<ChipType> cached_chip_type{};
 };
 } // namespace app::driver::llcc68
 
diff --git a/src/llcc68.cpp b/src/llcc68.cpp
index eeb41cd..5b25588 100644
--- a/src/llcc68.cpp
+++ b/src/llcc68.cpp
@@ -674,6 +674,10 @@ expected<unit, error_code> LLCC68::set_standby() {
 }
 
 expected<ChipType, error_code> LLCC68::hal_get_chip_type() {
+	if (cached_chip_type.has_value()) {
+		return *cached_chip_type;
+	}
+
 	constexpr auto SX1262_CHIP_TYPE = "SX1262";
 	constexpr auto LLCC68_CHIP_TYPE = "LLCC68";
 	constexpr auto SX1261_CHIP_TYPE = "SX1261";
@@ -684,16 +688,19 @@ expected<ChipType, error_code> LLCC68::hal_get_chip_type() {
 	auto r           = read_register(RADIOLIB_SX126X_REG_VERSION_STRING, version_buf);
 	APP_RADIO_RETURN_ERR(r);
 	LOG_HEXDUMP_DBG(version, sizeof(version), "version dump");
+
+	ChipType chip_type = ChipType::Unknown;
 	if (strncmp(version, LLCC68_CHIP_TYPE, 6) == 0) {
-		return ChipType::LLCC68;
+		chip_type = ChipType::LLCC68;
+	} else if (strncmp(version, SX1261_CHIP_TYPE, 6) == 0) {
+		chip_type = ChipType::SX1261;
+	} else if (strncmp(version, SX1262_CHIP_TYPE, 6) == 0) {
+		chip_type = ChipType::SX1262;
 	}
-	if (strncmp(version, SX1261_CHIP_TYPE, 6) == 0) {
-		return ChipType::SX1261;
+	if (chip_type != ChipType::Unknown) {
+		cached_chip_type = chip_type;
 	}
-	if (strncmp(version, SX1262_CHIP_TYPE, 6) == 0) {
-		return ChipType::SX1262;
-	}
-	return ChipType::Unknown;
+	return chip_type;
 }
 
 expected<unit, error_code> LLCC68::set_dio_irq_params(irq_params_t params) {