Add rc522 (#1298)

* wip

* first working

* feat complete

* add CODEOWNERS

* renamed to spi, reset optional

* add test

* fix CODEOWNERS

esphome/components/rc522_spi/binary_sensor.py

@@ -0,0 +1,44 @@
+import esphome.codegen as cg
+import esphome.config_validation as cv
+from esphome.components import binary_sensor
+from esphome.const import CONF_UID, CONF_ID
+from esphome.core import HexInt
+from . import rc522_spi_ns, RC522
+
+DEPENDENCIES = ['rc522_spi']
+
+CONF_RC522_ID = 'rc522_id'
+
+
+def validate_uid(value):
+    value = cv.string_strict(value)
+    for x in value.split('-'):
+        if len(x) != 2:
+            raise cv.Invalid("Each part (separated by '-') of the UID must be two characters "
+                             "long.")
+        try:
+            x = int(x, 16)
+        except ValueError as err:
+            raise cv.Invalid("Valid characters for parts of a UID are 0123456789ABCDEF.") from err
+        if x < 0 or x > 255:
+            raise cv.Invalid("Valid values for UID parts (separated by '-') are 00 to FF")
+    return value
+
+
+RC522BinarySensor = rc522_spi_ns.class_('RC522BinarySensor', binary_sensor.BinarySensor)
+
+CONFIG_SCHEMA = binary_sensor.BINARY_SENSOR_SCHEMA.extend({
+    cv.GenerateID(): cv.declare_id(RC522BinarySensor),
+    cv.GenerateID(CONF_RC522_ID): cv.use_id(RC522),
+    cv.Required(CONF_UID): validate_uid,
+})
+
+
+def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    yield binary_sensor.register_binary_sensor(var, config)
+
+    hub = yield cg.get_variable(config[CONF_RC522_ID])
+    cg.add(hub.register_tag(var))
+    addr = [HexInt(int(x, 16)) for x in config[CONF_UID].split('-')]
+    cg.add(var.set_uid(addr))