Inital!

patlite_mqtt/device.py

@@ -0,0 +1,57 @@
+import errno
+import struct
+
+import usb.core
+import usb.util
+from usb.core import USBError
+
+VENDOR_ID = 0x191A
+PRODUCT_ID = 0x8003
+ENDPOINT = 1
+
+
+class PatliteDevice:
+    def __init__(self):
+        self._dev = None
+
+    def connect(self):
+        dev = usb.core.find(idVendor=VENDOR_ID, idProduct=PRODUCT_ID)
+        if dev is None:
+            raise RuntimeError(
+                f"Patlite not found (vendor={VENDOR_ID:#06x}, product={PRODUCT_ID:#06x})"
+            )
+
+        try:
+            if dev.is_kernel_driver_active(0):
+                dev.detach_kernel_driver(0)
+            dev.set_configuration()
+        except USBError as exc:
+            if exc.errno == errno.EACCES:
+                raise RuntimeError(
+                    "USB access denied. On headless hosts, run ./scripts/install-udev.sh, "
+                    "then 'newgrp patlite' (or re-login), unplug/replug the Patlite, and retry."
+                ) from exc
+            raise
+
+        self._dev = dev
+
+    def close(self):
+        if self._dev is not None:
+            self.send(0x00, 0x00, 0x00)
+            usb.util.dispose_resources(self._dev)
+            self._dev = None
+
+    def send(self, ry: int, gb: int, w: int):
+        if self._dev is None:
+            return
+        data = struct.pack(
+            "BBBBBBBx",
+            0x00,
+            0x00,
+            0x0F,
+            0x00,
+            ry & 0xFF,
+            gb & 0xFF,
+            w & 0xFF,
+        )
+        self._dev.write(ENDPOINT, data)