diff --git a/esphome/components/binary_sensor/__init__.py b/esphome/components/binary_sensor/__init__.py
index 3f11e18e45..1eab76d54e 100644
--- a/esphome/components/binary_sensor/__init__.py
+++ b/esphome/components/binary_sensor/__init__.py
@@ -49,6 +49,7 @@ from esphome.const import (
     DEVICE_CLASS_SMOKE,
     DEVICE_CLASS_SOUND,
     DEVICE_CLASS_TAMPER,
+    DEVICE_CLASS_UPDATE,
     DEVICE_CLASS_VIBRATION,
     DEVICE_CLASS_WINDOW,
 )
@@ -82,6 +83,7 @@ DEVICE_CLASSES = [
     DEVICE_CLASS_SMOKE,
     DEVICE_CLASS_SOUND,
     DEVICE_CLASS_TAMPER,
+    DEVICE_CLASS_UPDATE,
     DEVICE_CLASS_VIBRATION,
     DEVICE_CLASS_WINDOW,
 ]
diff --git a/esphome/components/hm3301/aqi_calculator.h b/esphome/components/hm3301/aqi_calculator.h
index 1410eac72b..a3839b643c 100644
--- a/esphome/components/hm3301/aqi_calculator.h
+++ b/esphome/components/hm3301/aqi_calculator.h
@@ -33,7 +33,7 @@ class AQICalculator : public AbstractAQICalculator {
     int conc_lo = array[grid_index][0];
     int conc_hi = array[grid_index][1];
 
-    return ((aqi_hi - aqi_lo) / (conc_hi - conc_lo)) * (value - conc_lo) + aqi_lo;
+    return (value - conc_lo) * (aqi_hi - aqi_lo) / (conc_hi - conc_lo) + aqi_lo;
   }
 
   int get_grid_index_(uint16_t value, int array[AMOUNT_OF_LEVELS][2]) {
diff --git a/esphome/components/hm3301/caqi_calculator.h b/esphome/components/hm3301/caqi_calculator.h
index 51158454d0..a7f5460e0a 100644
--- a/esphome/components/hm3301/caqi_calculator.h
+++ b/esphome/components/hm3301/caqi_calculator.h
@@ -37,9 +37,7 @@ class CAQICalculator : public AbstractAQICalculator {
     int conc_lo = array[grid_index][0];
     int conc_hi = array[grid_index][1];
 
-    int aqi = ((aqi_hi - aqi_lo) / (conc_hi - conc_lo)) * (value - conc_lo) + aqi_lo;
-
-    return aqi;
+    return (value - conc_lo) * (aqi_hi - aqi_lo) / (conc_hi - conc_lo) + aqi_lo;
   }
 
   int get_grid_index_(uint16_t value, int array[AMOUNT_OF_LEVELS][2]) {
diff --git a/esphome/const.py b/esphome/const.py
index 128d12aad5..4bd02022d1 100644
--- a/esphome/const.py
+++ b/esphome/const.py
@@ -1,6 +1,6 @@
 """Constants used by esphome."""
 
-__version__ = "2021.11.0"
+__version__ = "2021.11.1"
 
 ALLOWED_NAME_CHARS = "abcdefghijklmnopqrstuvwxyz0123456789-_"
 
@@ -883,6 +883,7 @@ DEVICE_CLASS_SAFETY = "safety"
 DEVICE_CLASS_SMOKE = "smoke"
 DEVICE_CLASS_SOUND = "sound"
 DEVICE_CLASS_TAMPER = "tamper"
+DEVICE_CLASS_UPDATE = "update"
 DEVICE_CLASS_VIBRATION = "vibration"
 DEVICE_CLASS_WINDOW = "window"
 # device classes of both binary_sensor and sensor component