Add host target platform (#4783)

Co-authored-by: Otto winter <otto@otto-winter.com>

esphome/components/host/gpio.py

@@ -0,0 +1,73 @@
+import logging
+
+from esphome.const import (
+    CONF_ID,
+    CONF_INPUT,
+    CONF_INVERTED,
+    CONF_MODE,
+    CONF_NUMBER,
+    CONF_OPEN_DRAIN,
+    CONF_OUTPUT,
+    CONF_PULLDOWN,
+    CONF_PULLUP,
+)
+from esphome import pins
+import esphome.config_validation as cv
+import esphome.codegen as cg
+
+from .const import host_ns
+
+
+_LOGGER = logging.getLogger(__name__)
+
+
+HostGPIOPin = host_ns.class_("HostGPIOPin", cg.InternalGPIOPin)
+
+
+def _translate_pin(value):
+    if isinstance(value, dict) or value is None:
+        raise cv.Invalid(
+            "This variable only supports pin numbers, not full pin schemas "
+            "(with inverted and mode)."
+        )
+    if isinstance(value, int):
+        return value
+    try:
+        return int(value)
+    except ValueError:
+        pass
+    if value.startswith("GPIO"):
+        return cv.int_(value[len("GPIO") :].strip())
+    return value
+
+
+def validate_gpio_pin(value):
+    return _translate_pin(value)
+
+
+HOST_PIN_SCHEMA = cv.All(
+    {
+        cv.GenerateID(): cv.declare_id(HostGPIOPin),
+        cv.Required(CONF_NUMBER): validate_gpio_pin,
+        cv.Optional(CONF_MODE, default={}): cv.Schema(
+            {
+                cv.Optional(CONF_INPUT, default=False): cv.boolean,
+                cv.Optional(CONF_OUTPUT, default=False): cv.boolean,
+                cv.Optional(CONF_OPEN_DRAIN, default=False): cv.boolean,
+                cv.Optional(CONF_PULLUP, default=False): cv.boolean,
+                cv.Optional(CONF_PULLDOWN, default=False): cv.boolean,
+            }
+        ),
+        cv.Optional(CONF_INVERTED, default=False): cv.boolean,
+    },
+)
+
+
+@pins.PIN_SCHEMA_REGISTRY.register("host", HOST_PIN_SCHEMA)
+async def host_pin_to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    num = config[CONF_NUMBER]
+    cg.add(var.set_pin(num))
+    cg.add(var.set_inverted(config[CONF_INVERTED]))
+    cg.add(var.set_flags(pins.gpio_flags_expr(config[CONF_MODE])))
+    return var