Detach kernel driver before doing anything with device.

Initialization of the device must be done after device is detached from
kernel, otherwise exception will be thrown about device is busy message.

linak_ctrl.py

@@ -112,6 +112,10 @@ class LinakDevice:
         self._dev = usb.core.find(idVendor=LinakDevice.VEND,
                                   idProduct=LinakDevice.PROD)
 
+        # detach kernel driver, if attached
+        if self._dev.is_kernel_driver_active(0):
+            self._dev.detach_kernel_driver(0)
+
         # init device
         buf = [0 for _ in range(BUF_LEN)]
         buf[0] = MODE_OF_OPERATION          # 0x03 Feature report ID = 3
@@ -123,25 +127,18 @@ class LinakDevice:
         # hold a little bit, to make it effect.
         time.sleep(0.5)
 
-        # detach kernel driver, if attached
-        if self._dev.is_kernel_driver_active(0):
-            self._dev.detach_kernel_driver(0)
-
     def get_position(self, args):
-        if args.loop:
-            try:
-                while True:
-                    report = self._get_report()
-                    LOG.warning('Position: %s, height: %.2fcm, moving: %s',
-                                report.position, report.position_in_cm,
-                                report.moving)
-                    time.sleep(0.2)
-            except KeyboardInterrupt:
-                return
-        else:
-            report = self._get_report()
-            LOG.warning('Position: %s, height: %.2fcm, moving: %s',
-                        report.position, report.position_in_cm, report.moving)
+        try:
+            while True:
+                report = self._get_report()
+                LOG.warning('Position: %s, height: %.2fcm, moving: %s',
+                            report.position, report.position_in_cm,
+                            report.moving)
+                if not args.loop:
+                    break
+                time.sleep(0.2)
+        except KeyboardInterrupt:
+            return
 
     def move(self, args):
         retry_count = 3

requirements.txt

@@ -0,0 +1,2 @@
+pbr
+pyusb>=1.1.1

setup.cfg

@@ -0,0 +1,34 @@
+[metadata]
+name = linak-ctrl
+summary = Control Linak powered desks using USB2LIN06 cable. 
+description-file = README.rst
+author = Roman Dobosz
+author-email = gryf73@gmail.com
+home-page = https://gihtub.com/gryf/linak-ctrl
+license = BSD
+classifier =
+    Development Status :: 5 - Production/Stable
+    Environment :: Console
+    Intended Audience :: End Users/Desktop
+    License :: OSI Approved :: BSD License
+    Operating System :: POSIX :: Linux
+    Programming Language :: Python
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
+    Topic :: System :: Networking
+
+[install]
+record = install.log
+
+[options.entry_points]
+console_scripts =
+    linak-ctrl= linak_ctrl:main
+
+[options]
+install_requires =
+    pyusb
+
+[bdist_wheel]
+universal = 1

setup.py

@@ -0,0 +1,4 @@
+import setuptools
+
+
+setuptools.setup(setup_requires=['pbr>=2.0.0'], pbr=True)