From 70a51cdb5cbf280cd03f1a4eaf849e2cc543cc99 Mon Sep 17 00:00:00 2001
From: crosstyan <crosstyan@outlook.com>
Date: Fri, 15 Aug 2025 16:30:23 +0800
Subject: [PATCH] feat: introduce pa_setting_t structure for power amplifier
 configuration

---
 inc/llcc68.hpp             | 56 ++++++++++++++++++++++++++++----------
 inc/llcc68_definitions.hpp | 32 ++++++++++++++++++++++
 2 files changed, 73 insertions(+), 15 deletions(-)

diff --git a/inc/llcc68.hpp b/inc/llcc68.hpp
index d57729c..8d9f31e 100644
--- a/inc/llcc68.hpp
+++ b/inc/llcc68.hpp
@@ -781,11 +781,9 @@ set_tx_infinite_preamble() {
  * \param device_sel PA device selection; 0: SX1262, 1: SX1261
  */
 inline Result<Unit, error_t>
-set_pa_config(const uint8_t pa_duty_cycle,
-			  const uint8_t hp_max     = RADIOLIB_SX126X_PA_CONFIG_HP_MAX,
-			  const uint8_t device_sel = RADIOLIB_SX126X_PA_CONFIG_SX1262) {
+set_pa_config(pa_setting_t settings) {
 	// paLut reserved and always 0x01
-	const uint8_t data[] = {pa_duty_cycle, hp_max, device_sel, RADIOLIB_SX126X_PA_CONFIG_PA_LUT};
+	const uint8_t data[] = {settings.pa_duty_cycle, settings.hp_max, settings.device_sel, RADIOLIB_SX126X_PA_CONFIG_PA_LUT};
 	return spi::write_stream(RADIOLIB_SX126X_CMD_SET_PA_CONFIG, data);
 }
 
@@ -924,23 +922,51 @@ set_packet_type(const PacketType packet_type) {
 	return spi::write_stream(RADIOLIB_SX126X_CMD_SET_PACKET_TYPE, data);
 }
 
-
 inline Result<Unit, error_t>
 set_output_power(tx_params_t params) {
 	if (not in_range(params.power, -9, 22)) {
 		return ue_t{error_t{error::RADIO_INVALID_OUTPUT_POWER}};
 	}
-	uint8_t ocp = 0;
-	auto res    = read_register(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, std::span<uint8_t>{&ocp, 1});
-	APP_RADIO_RETURN_ERR(res);
+	Result<Unit, error_t> res;
 
-	// TODO: optimal setting table: for now it was applied with +22dBm best setting
-	res = set_pa_config(0x04);
-	APP_RADIO_RETURN_ERR(res);
-	res = set_tx_params(params);
-	APP_RADIO_RETURN_ERR(res);
-	// restore OCP configuration
-	return write_register(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, std::span<const uint8_t>{&ocp, 1});
+	// The OCP value is given on 6 bits, therefore the max OCP is 63 * 2.5mA = 157.5mA. It is configurable in steps of 2.5mA and the default value
+	// is re-configured automatically each time the function SetPaConfig(...) is called.
+	auto power = params.power;
+	if (power == 22) {
+		res = set_pa_config(pa_setting_t::Default22dBm());
+		APP_RADIO_RETURN_ERR(res);
+		params.power = 22;
+		res          = set_tx_params(params);
+		APP_RADIO_RETURN_ERR(res);
+	} else if (power == 20) {
+		// NOTE: it's optimal to set tx params to +22dBm
+		// and adjust the actual power by changing the duty cycle
+		res = set_pa_config(pa_setting_t::Default20dBm());
+		APP_RADIO_RETURN_ERR(res);
+		params.power = 22;
+		res          = set_tx_params(params);
+		APP_RADIO_RETURN_ERR(res);
+	} else if (power == 17) {
+		res = set_pa_config(pa_setting_t::Default17dBm());
+		APP_RADIO_RETURN_ERR(res);
+		params.power = 22;
+		res          = set_tx_params(params);
+		APP_RADIO_RETURN_ERR(res);
+	} else if (power == 14) {
+		res = set_pa_config(pa_setting_t::Default14dBm());
+		APP_RADIO_RETURN_ERR(res);
+		params.power = 22;
+		res          = set_tx_params(params);
+		APP_RADIO_RETURN_ERR(res);
+	} else {
+		// other power levels
+		// adjust tx params to achieve expected output power
+		res = set_pa_config(pa_setting_t::Default());
+		APP_RADIO_RETURN_ERR(res);
+		res = set_tx_params(params);
+		APP_RADIO_RETURN_ERR(res);
+	}
+	return {};
 }
 
 /**
diff --git a/inc/llcc68_definitions.hpp b/inc/llcc68_definitions.hpp
index eff9c1e..24d5d29 100644
--- a/inc/llcc68_definitions.hpp
+++ b/inc/llcc68_definitions.hpp
@@ -163,6 +163,38 @@ struct packet_params_t {
 	}
 };
 
+struct pa_setting_t {
+	uint8_t pa_duty_cycle;
+	uint8_t hp_max;
+	uint8_t device_sel;
+
+	static constexpr pa_setting_t Default22dBm() {
+		return {0x04, 0x07, 0x00};
+	}
+	/**
+	 * @note SetTxParams should be set to +22dBm
+	 */
+	static constexpr pa_setting_t Default20dBm() {
+		return {0x03, 0x05, 0x00};
+	}
+	/**
+	 * @note SetTxParams should be set to +22dBm
+	 */
+	static constexpr pa_setting_t Default17dBm() {
+		return {0x02, 0x03, 0x00};
+	}
+	/**
+	 * @note SetTxParams should be set to +14dBm
+	 */
+	static constexpr pa_setting_t Default14dBm() {
+		return {0x02, 0x02, 0x00};
+	}
+
+	static constexpr pa_setting_t Default() {
+		return Default22dBm();
+	}
+};
+
 inline const char *to_str(llcc68::TxRampTime ramp_time) {
 	switch (ramp_time) {
 	case llcc68::SET_RAMP_10U: