Corrected link in discovery.rst and Xiaomi Air Purifier Pro fix

docs/discovery.rst

@@ -43,7 +43,7 @@ encryption token must be known.
 If the returned a token is with characters other than ``0``\ s or ``f``\ s,
 it is likely a valid token which can be used directly for communication.
 If not, the token needs to be extracted from the Mi Home Application,
-see :ref:`creating_backup` for information how to do this.
+see :ref:`logged_tokens` for information how to do this.
 
 .. IMPORTANT::
 
@@ -85,14 +85,29 @@ potentially containing a valid token.
 
 Tokens full of ``0``\ s or ``f``\ s (as above) are either already paired
 with the mobile app or will not yield a token through this method.
-In those cases the procedure shown in :ref:`creating_backup` has to be used.
+In those cases the procedure shown in :ref:`logged_tokens` has to be used.
+
+.. _logged_tokens:
+
+Tokens from Mi Home logs
+========================
+
+The easiest way to obtain tokens is to browse through log files of the Mi Home
+app version 5.4.49 for Android. It seems that version was released with debug
+messages turned on by mistake. An APK file with the old version can be easily
+found using one of the popular web search engines. After downgrading use a file
+browser to navigate to directory ``SmartHome/logs/plug_DeviceManager``, then
+open the most recent file and search for the token. When finished, use Google
+Play to get the most recent version back.
 
 .. _creating_backup:
 
 Tokens from backups
 ===================
 
-Extracting tokens from a Mi Home backup is the preferred way to obtain tokens.
+Extracting tokens from a Mi Home backup is the preferred way to obtain tokens
+if they cannot be looked up in the Mi Home app version 5.4.49 log files
+(e.g. no Android device around).
 For this to work the devices have to be added to the app beforehand
 before the database (or backup) is extracted.
 

miio/airpurifier.py

@@ -455,14 +455,14 @@ def set_mode(self, mode: OperationMode):
     )
     def set_favorite_level(self, level: int):
         """Set favorite level."""
-        if level < 0 or level > 16:
+        if level < 0 or level > 17:
             raise AirPurifierException("Invalid favorite level: %s" % level)
 
         # Possible alternative property: set_speed_favorite
 
         # Set the favorite level used when the mode is `favorite`,
-        # should be  between 0 and 16.
-        return self.send("set_level_favorite", [level])  # 0 ... 16
+        # should be  between 0 and 17.
+        return self.send("set_level_favorite", [level])  # 0 ... 17
 
     @command(
         click.argument("brightness", type=EnumType(LedBrightness, False)),