Minimally fix remainder of Circuits.GPIO 2.0 updates

Author: fhunleth

lib/circuits_sim/device/gpio_button.ex

@@ -80,11 +80,6 @@ defmodule CircuitsSim.Device.GPIOButton do
       "Button #{state.state} connected with #{state.connection}"
     end
 
-    @impl GPIODevice
-    def info(state) do
-      %{device: __MODULE__, value: state.state}
-    end
-
     @impl GPIODevice
     def handle_message(state, {:press, duration}) do
       if duration != :infinity do

lib/circuits_sim/device/gpio_led.ex

@@ -39,11 +39,6 @@ defmodule CircuitsSim.Device.GPIOLED do
     defp led_string(0), do: "off"
     defp led_string(1), do: "on"
 
-    @impl GPIODevice
-    def info(state) do
-      %{device: __MODULE__, value: state.value}
-    end
-
     @impl GPIODevice
     def handle_message(state, _message) do
       {:ok, state}

lib/circuits_sim/gpio/backend.ex

@@ -9,16 +9,32 @@ defmodule CircuitsSim.GPIO.Backend do
   alias CircuitsSim.GPIO.GPIOServer
   alias CircuitsSim.GPIO.Handle
 
+  @impl Backend
+  def enumerate(_options) do
+    DeviceRegistry.bus_names(:gpio)
+  end
+
+  @impl Backend
+  def identifiers(gpio_spec, _options) do
+    # Simplest possible implementation for now.
+    {:ok, %{controller: "sim", label: "unknown", location: gpio_spec}}
+  end
+
+  @impl Backend
+  def status(_gpio_spec, _options) do
+    {:error, :unimplemented}
+  end
+
   @doc """
   Open an GPIO handle
   """
   @impl Backend
   def open(gpio_spec, direction, options) do
     with {:ok, identifiers} <- identifiers(gpio_spec, options),
-         handle = %Handle{gpio_spec: identifiers.gpio_spec},
-         :ok <- GPIOServer.set_direction(identifiers.gpio_spec, direction),
-         :ok <- set_pull_mode(identifiers.gpio_spec, options[:pull_mode]),
-         :ok <- set_initial_value(identifiers.gpio_spec, options[:initial_value]) do
+         handle = %Handle{gpio_spec: identifiers.location},
+         :ok <- GPIOServer.set_direction(identifiers.location, direction),
+         :ok <- set_pull_mode(identifiers.location, options[:pull_mode]),
+         :ok <- set_initial_value(identifiers.location, options[:initial_value]) do
       {:ok, handle}
     end
   end
@@ -33,7 +49,7 @@ defmodule CircuitsSim.GPIO.Backend do
   Return information about this backend
   """
   @impl Backend
-  def info() do
+  def backend_info() do
     %{backend: __MODULE__}
   end
 end

lib/circuits_sim/gpio/gpio_device.ex

@@ -23,12 +23,6 @@ defprotocol CircuitsSim.GPIO.GPIODevice do
   @spec write(t(), GPIO.value()) :: t()
   def write(dev, value)
 
-  @doc """
-  Return info about the GPIO like Circuits.GPIO.info/1
-  """
-  @spec info(t()) :: map()
-  def info(dev)
-
   @doc """
   Return the internal state as ASCII art
   """
@@ -49,7 +43,7 @@ defprotocol CircuitsSim.GPIO.GPIODevice do
   @doc """
   Handle a message sent to the GenServer running the device
 
-  These are used for timeouts or
+  These are used for timeouts or other events
   """
   @spec handle_info(t(), any()) :: t()
   def handle_info(dev, message)

lib/circuits_sim/gpio/gpio_server.ex

@@ -59,7 +59,7 @@ defmodule CircuitsSim.GPIO.GPIOServer do
     GenServer.call(via_name(gpio_spec), :read)
   end
 
-  @spec set_direction(GPIO.gpio_spec(), GPIO.pin_direction()) :: :ok | {:error, atom()}
+  @spec set_direction(GPIO.gpio_spec(), GPIO.direction()) :: :ok | {:error, atom()}
   def set_direction(gpio_spec, direction) do
     GenServer.call(via_name(gpio_spec), {:set_direction, direction})
   end
@@ -132,10 +132,6 @@ defmodule CircuitsSim.GPIO.GPIOServer do
     {:reply, GPIODevice.render(state.device), state}
   end
 
-  def handle_call(:info, _from, state) do
-    {:reply, GPIODevice.info(state.device), state}
-  end
-
   def handle_call({:send_message, message}, _from, state) do
     {result, new_device} = GPIODevice.handle_message(state.device, message)
     state = %{state | device: new_device}

lib/circuits_sim/gpio/handle.ex

@@ -47,10 +47,5 @@ defmodule CircuitsSim.GPIO.Handle do
 
     @impl Handle
     def close(%CircuitsSim.GPIO.Handle{}), do: :ok
-
-    @impl Handle
-    def info(%CircuitsSim.GPIO.Handle{} = handle) do
-      GPIOServer.info(handle.pin_spec)
-    end
   end
 end