From 2cea093fdbf82f745c437b46851feed887f8a99f Mon Sep 17 00:00:00 2001
From: Voltafield <sales@voltafield.com>
Date: Thu, 21 May 2026 09:53:20 +0800
Subject: [PATCH] fix(sensors): af9838 minor code style and architecture
 updates (#27370)

* drivers: af9838 minor fixes and code style updates

* Update af9838_main.cpp

* Update af9838.cpp

* Update af9838.hpp
---
 .../magnetometer/voltafield/af9838/af9838.cpp | 64 +------------------
 .../magnetometer/voltafield/af9838/af9838.hpp | 13 +---
 .../voltafield/af9838/af9838_main.cpp         | 11 +---
 3 files changed, 3 insertions(+), 85 deletions(-)

diff --git a/src/drivers/magnetometer/voltafield/af9838/af9838.cpp b/src/drivers/magnetometer/voltafield/af9838/af9838.cpp
index 080fd8e6cb..1d49bc1799 100644
--- a/src/drivers/magnetometer/voltafield/af9838/af9838.cpp
+++ b/src/drivers/magnetometer/voltafield/af9838/af9838.cpp
@@ -31,63 +31,9 @@
  ****************************************************************************/
 #include "af9838.hpp"
 
-#ifdef VTC_DRIVER_MED_FILTER
-void AF9838_Driver::af9838_median_filter(float *mag)
-{
-	uint16_t i, j, k;
-	float mft_tmp[3][MED_FILTER_MAX_NUM];
-	float tmp;
-
-	if (_mdf_init_idx < _mdf_num) {
-		for (i = 0; i < 3; i++) {
-			_mdf_data[i][_mdf_init_idx] = mag[i];
-		}
-
-		_mdf_init_idx++;
-		return;
-
-	} else {
-		for (i = 0; i < 3; i++) {
-			_mdf_data[i][_mdf_data_idx] = mag[i];
-		}
-	}
-
-	if (++_mdf_data_idx >= _mdf_num) {
-		_mdf_data_idx = 0;
-	}
-
-	for (i = 0; i < 3; i++) {
-		for (j = 0; j < _mdf_num; j++) {
-			mft_tmp[i][j] = _mdf_data[i][j];
-		}
-	}
-
-	for (i = 0; i < 3; i++) {
-		for (j = 0; j < (_mdf_num - 1); j++) {
-			for (k = 0; k < (_mdf_num - 1 - j); k++) {
-				if (mft_tmp[i][k] < mft_tmp[i][k + 1]) {
-					tmp = mft_tmp[i][k];
-					mft_tmp[i][k] = mft_tmp[i][k + 1];
-					mft_tmp[i][k + 1] = tmp;
-				}
-			}
-		}
-	}
-
-	for (i = 0; i < 3; i++) {
-		mag[i] = mft_tmp[i][(uint16_t)((_mdf_num - 1) / 2)];
-	}
-}
-#endif
-
-
 using namespace AF9838;
 using namespace time_literals;
 
-
-float AF9838::g_cli_rate_hz = 100.0f;
-
-
 AF9838_Driver::AF9838_Driver(const I2CSPIDriverConfig &config)
 	: device::I2C(config),
 	  I2CSPIDriver(config),
@@ -159,7 +105,7 @@ int AF9838_Driver::init()
 		return PX4_ERROR;
 	}
 
-	float hz = g_cli_rate_hz;
+	float hz = AF9838::DEFAULT_RATE_HZ;
 
 	if (hz < 1.f) { hz = 1.f; }
 
@@ -269,14 +215,6 @@ void AF9838_Driver::RunImpl()
 				my_uT = ry * AF9838::LSB_TO_uT;
 				mz_uT = rz * AF9838::LSB_TO_uT;
 
-#ifdef VTC_DRIVER_MED_FILTER
-				float mag_uT[3] = { mx_uT, my_uT, mz_uT };
-				af9838_median_filter(mag_uT);
-				mx_uT = mag_uT[0];
-				my_uT = mag_uT[1];
-				mz_uT = mag_uT[2];
-#endif
-
 				mx_G = mx_uT * AF9838::uT_TO_G;
 				my_G = my_uT * AF9838::uT_TO_G;
 				mz_G = mz_uT * AF9838::uT_TO_G;
diff --git a/src/drivers/magnetometer/voltafield/af9838/af9838.hpp b/src/drivers/magnetometer/voltafield/af9838/af9838.hpp
index 831d1cf941..f0fd373eab 100644
--- a/src/drivers/magnetometer/voltafield/af9838/af9838.hpp
+++ b/src/drivers/magnetometer/voltafield/af9838/af9838.hpp
@@ -53,7 +53,7 @@
 
 namespace AF9838
 {
-extern float g_cli_rate_hz;
+static constexpr float DEFAULT_RATE_HZ = 100.0f;
 static constexpr float LSB_TO_uT = 0.1f;    // micro-Tesla / LSB
 static constexpr float uT_TO_G   = 0.01f;   // µT → Gauss
 static constexpr float ONE_G = 9.80665f;
@@ -97,17 +97,6 @@ private:
 	bool            _running{false};
 	bool _waiting_data{false};
 	hrt_abstime _last_trigger{0};
-	bool            _algo_inited{false};
-
-	static constexpr uint16_t AF9838_MED_FILTER_MAX_NUM = 15;
-	static constexpr uint16_t AF9838_MED_FILTER_NUMBER  = 5;
-
-	uint16_t _mdf_num      = AF9838_MED_FILTER_NUMBER;
-	uint16_t _mdf_init_idx = 0;
-	uint16_t _mdf_data_idx = 0;
-	float    _mdf_data[3][AF9838_MED_FILTER_MAX_NUM] {};
-
-	void af9838_median_filter(float mag[3]);
 
 	uORB::Subscription _accel_sub {ORB_ID(vehicle_acceleration)};
 	hrt_abstime _last_accel_ts{0};
diff --git a/src/drivers/magnetometer/voltafield/af9838/af9838_main.cpp b/src/drivers/magnetometer/voltafield/af9838/af9838_main.cpp
index f761866d76..8294b2d8a8 100644
--- a/src/drivers/magnetometer/voltafield/af9838/af9838_main.cpp
+++ b/src/drivers/magnetometer/voltafield/af9838/af9838_main.cpp
@@ -42,7 +42,6 @@ void AF9838_Driver::print_usage()
 	PRINT_MODULE_USAGE_PARAMS_I2C_SPI_DRIVER(true, false);
 	PRINT_MODULE_USAGE_PARAMS_I2C_ADDRESS(0x0C);
 	PRINT_MODULE_USAGE_PARAM_INT('R', 0, 0, 35, "Rotation", true);
-	PRINT_MODULE_USAGE_PARAM_FLOAT('r', 100.f, 1.f, 1000.f, "Output rate (Hz)", true);
 	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();
 }
 
@@ -59,19 +58,11 @@ extern "C" __EXPORT int af9838_main(int argc, char *argv[])
 	cli.i2c_address = I2C_ADDRESS_DEFAULT;
 	cli.default_i2c_frequency = I2C_SPEED;
 
-	AF9838::g_cli_rate_hz = 100.0f;
-
-	while ((ch = cli.getOpt(argc, argv, "R:r:")) != EOF) {
+	while ((ch = cli.getOpt(argc, argv, "R:")) != EOF) {
 		switch (ch) {
 		case 'R':
 			cli.rotation = (enum Rotation)atoi(cli.optArg());
 			break;
-
-		case 'r': {
-				const float rate = atof(cli.optArg());
-				AF9838::g_cli_rate_hz = rate;
-				break;
-			}
 		}
 	}