Linux Refactor: Episode 2: Attack of the Overlays

core/services/ardupilot_manager/ArduPilotManager.py

@@ -178,6 +178,7 @@ def get_default_params_cmdline(self, platform: Platform) -> str:
 
     async def start_linux_board(self, board: LinuxFlightController) -> None:
         self._current_board = board
+        board.setup_board()
         if not self.firmware_manager.is_firmware_installed(self._current_board):
             if board.platform == Platform.Navigator:
                 self.firmware_manager.install_firmware_from_file(

core/services/ardupilot_manager/flight_controller_detector/linux/hardware_setup/overlay_source/spi0-led.dts

@@ -0,0 +1,44 @@
+// This is a custom device tree overlay for the spi0 peripheral on the
+// Raspberry Pi 4. It will configure only the spi0 mosi pin
+// (The other spi0 pins will not be driven by the spi0 peripheral,
+// and can be used for other functions). This is to be used with
+// the Blue Robotics Navigator autopilot hat, where the RGB
+// 'neopixel' led data pin is connected to the spi0 mosi pin on the
+// Raspberry Pi 4.
+
+/dts-v1/;
+/plugin/;
+
+
+/ {
+    compatible = "brcm,bcm2835";
+
+    fragment@0 {
+        target = <&spi0_cs_pins>;
+        frag0: __overlay__ {
+            brcm,pins = <>;
+        };
+    };
+
+    fragment@1 {
+        target = <&spi0>;
+        frag1: __overlay__ {
+            cs-gpios = <>;
+            status = "okay";
+        };
+    };
+
+    fragment@2 {
+        target = <&spidev1>;
+        __overlay__ {
+            status = "disabled";
+        };
+    };
+
+    fragment@3 {
+        target = <&spi0_pins>;
+        __overlay__ {
+            brcm,pins = <10>;
+        };
+    };
+};

core/services/ardupilot_manager/flight_controller_detector/linux/hardware_setup/peripheral_configuration.py

@@ -0,0 +1,163 @@
+import re
+import shlex
+import subprocess
+import time
+from dataclasses import dataclass
+from typing import List, Optional
+
+all_dtparams = [
+    "i2c_vc=on",
+    "i2c_arm_baudrate=1000000",
+    "spi=on",
+    "enable_uart=1",
+]
+
+
+other_overlays = [
+    "dwc2 dr_mode=otg",
+]
+devices = {
+    "ADS1115": (0x48, 1),
+    "AK09915": (0x0C, 1),
+    "BME280": (0x76, 1),
+    "PCA9685": (0x40, 4),
+}
+
+
+class SetupError(Exception):
+    pass
+
+
+@dataclass
+class I2cDevice:
+    device: str
+    overlay: str
+    pins: dict[int, str]
+
+
+@dataclass
+class SpiDevice:
+    device: str
+    overlay: str
+    pins: dict[int, str]
+
+
+@dataclass
+class SerialDevice:
+    device: str
+    overlay: str
+    pins: dict[int, str]
+
+
+@dataclass
+class GpioSetup:
+    number: int
+    function: str
+    pull: str
+    value: str
+
+
+i2c_module = "i2c-dev"
+i2c_dtparams = [
+    "i2c_vc=on",
+    "i2c_arm_baudrate=1000000",
+]
+
+i2c_devices: List[I2cDevice] = [
+    I2cDevice(device="i2c-6", overlay="i2c6 pins_22_23=true baudrate=400000", pins={22: "SDA6", 23: "SCL6"}),
+    I2cDevice(device="i2c-1", overlay="i2c1", pins={2: "SDA1", 3: "SCL1"}),
+    I2cDevice(device="i2c-4", overlay="i2c4 pins_6_7=true baudrate=400000", pins={6: "SDA4", 7: "SCL4"}),
+]
+
+spi_devices: List[SpiDevice] = [
+    SpiDevice(device="spidev1.0", overlay="spi1-3cs", pins={19: "SPI1_MISO", 20: "SPI1_MOSI", 21: "SPI1_SCLK"}),
+    SpiDevice(
+        device="spidev0.0",
+        overlay="spi0-led",
+        pins={
+            10: "SPI0_MOSI",
+        },
+    ),
+]
+
+gpios = [
+    GpioSetup(number=11, function="OUT", pull="UP", value="HIGH"),
+    GpioSetup(number=24, function="OUT", pull="UP", value="HIGH"),
+    GpioSetup(number=25, function="OUT", pull="UP", value="HIGH"),
+    GpioSetup(number=37, function="OUT", pull="DOWN", value="LOW"),
+]
+
+
+def enable_i2c_module() -> None:
+    modules = subprocess.check_output("lsmod")
+    if "i2c_dev" in str(modules):
+        return
+    print(f"loading module {i2c_module}...")
+    output = subprocess.check_output(shlex.split(f"modprobe {i2c_module}"))
+    print(output)
+
+
+def enable_spi_module() -> None:
+    modules = subprocess.check_output("lsmod")
+    if "spi_dev" in str(modules):
+        return
+    print(f"loading module {i2c_module}...")
+    output = subprocess.check_output(shlex.split(f"modprobe {i2c_module}"))
+    print(output)
+
+
+@dataclass
+class GpioState:
+    number: int
+    level: int
+    fsel: int
+    alt: Optional[int]
+    func: str
+    pull: str
+
+
+def get_gpios_state() -> dict[int, GpioState]:
+    output = subprocess.check_output(["raspi-gpio", "get"]).decode("utf-8")
+    pattern = r"GPIO (?P<gpio>\d+): level=(?P<level>\d) fsel=(?P<fsel>\d)(?: alt=(?P<alt>\d))? func=(?P<func>[\w\d_]+) pull=(?P<pull>\w+)"
+
+    # Using findall to extract all matches
+    matches = re.finditer(pattern, output)
+    gpio_states = {}
+    # Print each match
+    for match in matches:
+        gpio_states[int(match.group("gpio"))] = GpioState(
+            number=int(match.group("gpio")),
+            level=int(match.group("level")),
+            fsel=int(match.group("fsel")),
+            alt=int(match.group("alt")) if match.group("alt") else None,
+            func=match.group("func"),
+            pull=match.group("pull"),
+        )
+    return gpio_states
+
+
+def load_overlay(overlay: str) -> None:
+    output = subprocess.check_output(shlex.split(f"dtoverlay {overlay}")).decode("utf-8")
+    print(output)
+
+
+enable_i2c_module()
+enable_spi_module()
+
+states = get_gpios_state()
+all_devices: List[I2cDevice | SpiDevice] = [*i2c_devices, *spi_devices]
+for device in all_devices:
+    needs_reload = False
+    for gpio, function in device.pins.items():
+        if states[gpio].func != function:
+            print(f"GPIO {gpio} is not configured as {function}, instad it is {states[gpio].func}")
+            print(f"{device.overlay} needs to be loaded")
+            needs_reload = True
+    if needs_reload:
+        load_overlay(device.overlay)
+        time.sleep(2)
+        new_state = get_gpios_state()
+        for gpio, function in device.pins.items():
+            if states[gpio].func != function:
+                print(f"GPIO {gpio} is STILL not configured as {function}, instad it is {states[gpio].func}")
+                raise SetupError("Failed to configure device")

core/services/ardupilot_manager/flight_controller_detector/linux/linux_boards.py

@@ -22,6 +22,9 @@ def get_serial_cmdlines(self) -> str:
     def get_serials(self) -> List[Serial]:
         raise NotImplementedError
 
+    def setup_board(self) -> None:
+        raise NotImplementedError
+
     def check_for_i2c_device(self, bus_number: int, address: int) -> bool:
         try:
             bus = SMBus(bus_number)