libhackrf: add 'hackrf_radio_set_frequency_fp()' and 'hackrf_radio_set_sample_rate_fp()'

Author: antoinevg

firmware/hackrf_usb/CMakeLists.txt

@@ -56,6 +56,7 @@ set(SRC_M4
 	usb_endpoint.c
 	usb_api_board_info.c
 	usb_api_m0_state.c
+	usb_api_radio.c
 	usb_api_register.c
 	usb_api_spiflash.c
 	usb_api_transceiver.c

firmware/hackrf_usb/hackrf_usb.c

@@ -75,6 +75,7 @@
 #include "usb_api_board_info.h"
 #include "usb_api_m0_state.h"
 #include "usb_api_operacake.h"
+#include "usb_api_radio.h"
 #include "usb_api_register.h"
 #include "usb_api_selftest.h"
 #include "usb_api_spiflash.h"
@@ -183,6 +184,8 @@ static usb_request_handler_fn vendor_request_handler[] = {
 	usb_vendor_request_read_radio_reg,
 	usb_vendor_request_get_buffer_size,
 	usb_vendor_request_lock_radio_reg,
+	usb_vendor_request_set_radio_frequency_fp,
+	usb_vendor_request_set_radio_sample_rate_fp,
 };
 
 static const uint32_t vendor_request_handler_count =

firmware/hackrf_usb/usb_api_radio.c

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2026 Great Scott Gadgets <info@greatscottgadgets.com>
+ *
+ * This file is part of HackRF.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include <stddef.h>
+
+#include <fixed_point.h>
+#include <radio.h>
+#include <usb_request.h>
+#include <usb_type.h>
+
+#include "usb_queue.h"
+
+usb_request_status_t usb_vendor_request_set_radio_frequency_fp(
+	usb_endpoint_t* const endpoint,
+	const usb_transfer_stage_t stage)
+{
+	static fp_40_24_t hz_param;
+
+	if (stage == USB_TRANSFER_STAGE_SETUP) {
+		usb_transfer_schedule_block(
+			endpoint->out,
+			&hz_param,
+			sizeof(fp_40_24_t),
+			NULL,
+			NULL);
+	} else if (stage == USB_TRANSFER_STAGE_DATA) {
+		radio_reg_write(&radio, RADIO_BANK_ACTIVE, RADIO_FREQUENCY_RF, hz_param);
+		radio_reg_write(
+			&radio,
+			RADIO_BANK_ACTIVE,
+			RADIO_FREQUENCY_IF,
+			RADIO_UNSET);
+		radio_reg_write(
+			&radio,
+			RADIO_BANK_ACTIVE,
+			RADIO_FREQUENCY_LO,
+			RADIO_UNSET);
+		radio_reg_write(
+			&radio,
+			RADIO_BANK_ACTIVE,
+			RADIO_IMAGE_REJECT,
+			RADIO_UNSET);
+		usb_transfer_schedule_ack(endpoint->in);
+	}
+
+	return USB_REQUEST_STATUS_OK;
+}
+
+usb_request_status_t usb_vendor_request_set_radio_sample_rate_fp(
+	usb_endpoint_t* const endpoint,
+	const usb_transfer_stage_t stage)
+{
+	static fp_28_36_t sps_param;
+
+	if (stage == USB_TRANSFER_STAGE_SETUP) {
+		usb_transfer_schedule_block(
+			endpoint->out,
+			&sps_param,
+			sizeof(fp_28_36_t),
+			NULL,
+			NULL);
+	} else if (stage == USB_TRANSFER_STAGE_DATA) {
+		radio_reg_write(&radio, RADIO_BANK_ACTIVE, RADIO_SAMPLE_RATE, sps_param);
+		usb_transfer_schedule_ack(endpoint->in);
+	}
+
+	return USB_REQUEST_STATUS_OK;
+}

firmware/hackrf_usb/usb_api_radio.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2026 Great Scott Gadgets <info@greatscottgadgets.com>
+ *
+ * This file is part of HackRF.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#pragma once
+
+#include <usb_request.h>
+#include <usb_type.h>
+
+usb_request_status_t usb_vendor_request_set_radio_frequency_fp(
+	usb_endpoint_t* const endpoint,
+	const usb_transfer_stage_t stage);
+
+usb_request_status_t usb_vendor_request_set_radio_sample_rate_fp(
+	usb_endpoint_t* const endpoint,
+	const usb_transfer_stage_t stage);

host/libhackrf/src/hackrf.c

@@ -121,6 +121,8 @@ typedef enum {
 	HACKRF_VENDOR_REQUEST_RADIO_READ_REG = 60,
 	HACKRF_VENDOR_REQUEST_GET_BUFFER_SIZE = 61,
 	HACKRF_VENDOR_REQUEST_RADIO_LOCK_REG = 62,
+	HACKRF_VENDOR_REQUEST_RADIO_SET_FREQUENCY_FP = 63,
+	HACKRF_VENDOR_REQUEST_RADIO_SET_SAMPLE_RATE_FP = 64,
 } hackrf_vendor_request;
 
 #define USB_CONFIG_STANDARD 0x1
@@ -1843,6 +1845,36 @@ int ADDCALL hackrf_set_freq_explicit(
 	}
 }
 
+int ADDCALL hackrf_radio_set_frequency_fp(hackrf_device* device, const fp_40_24_t freq_hz)
+{
+	USB_API_REQUIRED(device, 0x0113);
+	uint64_t set_freq_fp_param;
+	uint8_t length;
+	int result;
+
+	// serialize parameters
+	set_freq_fp_param = TO_LE64(freq_hz);
+	length = sizeof(uint64_t);
+
+	result = libusb_control_transfer(
+		device->usb_device,
+		LIBUSB_ENDPOINT_OUT | LIBUSB_REQUEST_TYPE_VENDOR |
+			LIBUSB_RECIPIENT_DEVICE,
+		HACKRF_VENDOR_REQUEST_RADIO_SET_FREQUENCY_FP,
+		0,
+		0,
+		(unsigned char*) &set_freq_fp_param,
+		length,
+		DEFAULT_REQUEST_TIMEOUT);
+
+	if (result < length) {
+		last_libusb_error = result;
+		return HACKRF_ERROR_LIBUSB;
+	}
+
+	return HACKRF_SUCCESS;
+}
+
 typedef struct {
 	uint32_t freq_hz;
 	uint32_t divider;
@@ -1935,6 +1967,37 @@ int ADDCALL hackrf_set_sample_rate(hackrf_device* device, const double freq)
 	return hackrf_set_sample_rate_manual(device, freq_hz, divider);
 }
 
+int ADDCALL hackrf_radio_set_sample_rate_fp(
+	hackrf_device* device,
+	const fp_28_36_t freq_hz)
+{
+	USB_API_REQUIRED(device, 0x0113);
+	uint64_t set_sr_fp_param;
+	uint8_t length;
+	int result;
+
+	set_sr_fp_param = TO_LE64(freq_hz);
+	length = sizeof(uint64_t);
+
+	result = libusb_control_transfer(
+		device->usb_device,
+		LIBUSB_ENDPOINT_OUT | LIBUSB_REQUEST_TYPE_VENDOR |
+			LIBUSB_RECIPIENT_DEVICE,
+		HACKRF_VENDOR_REQUEST_RADIO_SET_SAMPLE_RATE_FP,
+		0,
+		0,
+		(unsigned char*) &set_sr_fp_param,
+		length,
+		DEFAULT_REQUEST_TIMEOUT);
+
+	if (result < length) {
+		last_libusb_error = result;
+		return HACKRF_ERROR_LIBUSB;
+	}
+
+	return HACKRF_SUCCESS;
+}
+
 int ADDCALL hackrf_set_amp_enable(hackrf_device* device, const uint8_t value)
 {
 	int result;

host/libhackrf/src/hackrf.h

@@ -946,6 +946,16 @@ enum clkin_ctrl_signal {
 	CLKIN_SIGNAL_P22 = 1,
 };
 
+/**
+ * 40.24 Fixed-point type.
+ */
+typedef uint64_t fp_40_24_t;
+
+/**
+ * 28.36 Fixed-point type.
+ */
+typedef uint64_t fp_28_36_t;
+
 /**
  * Opaque struct for hackrf device info. Object can be created via @ref hackrf_open, @ref hackrf_device_list_open or @ref hackrf_open_by_serial and be destroyed via @ref hackrf_close
  * @ingroup device
@@ -1778,6 +1788,18 @@ extern ADDAPI int ADDCALL hackrf_set_freq_explicit(
 	const uint64_t lo_freq_hz,
 	const enum rf_path_filter path);
 
+/**
+ * Set the radio center frequency to a fractional, fixed-point value.
+ *
+ * @param[in] device device to query
+ * @param[in] hz center frequency in Hz
+ * @return @ref HACKRF_SUCCESS on success or @ref hackrf_error variant
+ * @ingroup configuration
+ */
+extern ADDAPI int ADDCALL hackrf_radio_set_frequency_fp(
+	hackrf_device* device,
+	const fp_40_24_t freq_hz);
+
 /**
  * Set sample rate explicitly
  * 
@@ -1812,6 +1834,20 @@ extern ADDAPI int ADDCALL hackrf_set_sample_rate(
 	hackrf_device* device,
 	const double freq_hz);
 
+/**
+ * Set the radio sample rate to a fractional, fixed-point value.
+ *
+ * This function does not automatically configure the baseband filter bandwidth, so any calls to this function should be followed by @ref hackrf_set_baseband_filter_bandwidth should it require adjustment.
+ *
+ * @param[in] device device to query
+ * @param[in] sps samples per second
+ * @return @ref HACKRF_SUCCESS on success or @ref hackrf_error variant
+ * @ingroup configuration
+ */
+extern ADDAPI int ADDCALL hackrf_radio_set_sample_rate_fp(
+	hackrf_device* device,
+	const fp_28_36_t freq_hz);
+
 /**
  * Enable/disable 14dB RF amplifier
  *