Initial standalone sx126x driver [WIP]

Documentation/components/drivers/wireless/lpwan/sx126x.rst

@@ -0,0 +1,65 @@
+==================
+SX126x LoRa driver
+==================
+**Currently experimental. Changes can happen in the near future**
+
+.. image:: https://www.thethingsnetwork.org/docs/lorawan/transceivers/SX1261.jpg
+
+Short introduction SX126x
+=========================
+The SX126x is a LoRa chip by Semtech. Sometimes also found in chips with a different name but the same or similar sillicon underneath.
+The older variant is the SX127x, even with its higher number. The SX126x series promises to improve the link budget. They also added extra spreading factors.
+
+Userspace API
+=============
+This driver is controlled as a character device and using IOCTL commands. At the time of writing this 24 February, 2025, there is no common API **yet** for LoRa devices and other RF devices under ``/lpwan``.
+Currently this driver is controlled using older and driver specific IOCTL commands.
+
+Basic RF IOCTL
+--------------
+See ``nuttx/wireless/ioctl.h`` : ``WLIOC_x`` for setting the basic radio parameters such as frequency and power.
+Please note that frequency and power may be limited by the lower driver part at board logic.
+
+Driver dedicated IOCTL
+----------------------
+See ``nuttx/wireless/lpwan/sx126x.h`` : ``SX126XIOC_x`` for the commands.
+
+* The packet type is set using ``SX126XIOC_PACKETTYPESET`` which takes ``sx126x_packet_type_e`` enums. **Currently only LoRa packet type is supported.**
+
+* LoRa modulation and LoRa packets are configured using ``SX126XIOC_LORACONFIGSET`` which takes a pointer to a ``sx126x_lora_config_s`` struct. This struct contains two seperate structures for modulation and packet config. It is recommended to follow the SX126x datasheet at https://www.semtech.com/products/wireless-rf/lora-connect/sx1262 that gives more details about each parameter.
+
+Reading / Writing
+-----------------
+Reading and writing is done with the ``read`` and ``write`` functions.
+
+* ``write`` directly transmits the given bytes using the IOCTL configured parameters. **Does not support polling or timeout yet.**
+
+* ``read`` takes a pointer to ``sx126x_read_header_s``, which contains information about the received packet. **RSSI and SNR aren't implemented yet**. *Note that packets are always received, even when the CRC (checked using ``.crc_error``) failed.*
+
+Board implementation
+====================
+The driver can be registered in board logic using ``sx126x_register``, which takes an SPI bus, lower driver and the path.
+More information about ``struct sx126x_lower_s`` parameters can be found in detail under ``nuttx/wireless/lpwan/sx126x.h`` : ``struct sx126x_lower_s``.
+
+This driver supports multiple instances using ``dev_number`` found in ``sx126x_lower_s``. This is done so multiple channels of LoRa can work at the same time.
+
+**Do not assign random numbers in get_pa_values. This can damage the device depending on model. Refer to the manual**
+
+Testing
+=======
+A simple ping-pong test is made to test the device. This code can be used as an example. It is found here https://pastebin.com/71CdKZvm
+It takes the following parameters:
+
+* ``-f`` sets frequency in hz. The range is board depended.
+* ``-b`` sets the bandwidth in kHz and automatically selects the closest sx126x supported bandwidth.
+* ``-s`` sets the spreading factor between 5 and 12.
+* ``-p`` sets the power in dBm. The range is board depended. Also PA setting depended.
+* ``-t`` perform transmit. Transmit the following bytes.
+* ``-r`` perform receive. Receives and print.
+* ``-x`` perform transmit and receive. Transmits following bytes and attempts to receives immidiately. To be used with ``-e`` echo
+* ``-e`` perform echo. Listen and repeat.
+
+.. image:: https://private-user-images.githubusercontent.com/9679272/415904583-3a979608-6386-4b51-8d0e-acf09d918299.png?jwt=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.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.6JOsN_-uyyxnlxHg33Bt_WT5DFSO_i-Uh4coi-8xpEc
+
+:alt: Running sx126x -f 869250000 -b 250 -s 10 -p 22 -x "HELLO"
+

drivers/wireless/lpwan/Kconfig

@@ -12,6 +12,15 @@ config LPWAN_SX127X
 	---help---
 		This options adds driver support for the Samtech SX127X chip.
 
+config LPWAN_SX126X
+	bool "SX126X Low Power Long Range transceiver support"
+	default n
+	select SPI
+	---help---
+		This options adds driver support for the Samtech SX126X chip.
+
+source "drivers/wireless/lpwan/sx126x/Kconfig"
+
 if LPWAN_SX127X
 
 config LPWAN_SX127X_RFFREQ_DEFAULT

drivers/wireless/lpwan/Make.defs

@@ -25,5 +25,6 @@
 ifeq ($(CONFIG_DRIVERS_LPWAN),y)
 
 include wireless/lpwan/sx127x/Make.defs
+include wireless/lpwan/sx126x/Make.defs
 
 endif # CONFIG_DRIVERS_LPWAN

drivers/wireless/lpwan/sx126x/CMakeLists.txt

@@ -0,0 +1,24 @@
+# ##############################################################################
+# drivers/wireless/lpwan/sx126x/CMakeLists.txt
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more contributor
+# license agreements.  See the NOTICE file distributed with this work for
+# additional information regarding copyright ownership.  The ASF licenses this
+# file to you under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License.  You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+# ##############################################################################
+if(CONFIG_LPWAN_SX126X)
+  target_sources(drivers PRIVATE sx126x.c)
+endif()

drivers/wireless/lpwan/sx126x/Kconfig

@@ -0,0 +1,28 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+if LPWAN_SX126X
+
+config LPWAN_SX126X_RFFREQ_DEFAULT
+	int "SX126X default RF frequency Hz"
+	default 869252000
+
+config LPWAN_SX126X_SF_DEFAULT
+	int "SX126X default spreading factor"
+	default 10
+
+config LPWAN_SX126X_BW_DEFAULT
+	int "SX126X default bandwidth kHz"
+	default 125
+
+config LPWAN_SX126X_CR_DEFAULT
+	int "SX126X default coding rate"
+	default 8
+
+config LPWAN_SX126X_MAX_DEVICES
+	int "SX126X maximum devices"
+	default 1
+
+endif # DRIVERS_LPWAN

drivers/wireless/lpwan/sx126x/Make.defs

@@ -0,0 +1,35 @@
+############################################################################
+# drivers/wireless/lpwan/sx126x/Make.defs
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+# Include SX126X drivers into the build
+
+ifeq ($(CONFIG_LPWAN_SX126X),y)
+
+CSRCS += sx126x.c
+
+# Include SX126X build support
+
+DEPPATH += --dep-path wireless$(DELIM)lpwan$(DELIM)sx126x
+VPATH += :wireless$(DELIM)lpwan$(DELIM)sx126x
+CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)drivers$(DELIM)wireless$(DELIM)lpwan$(DELIM)sx126x
+
+endif # CONFIG_LPWAN_SX126X