diff --git a/power_manager/powerd/system/event_device.cc b/power_manager/powerd/system/event_device.cc
index f18d3e5..0d4b651 100644
--- a/power_manager/powerd/system/event_device.cc
+++ b/power_manager/powerd/system/event_device.cc
@@ -66,7 +66,19 @@
 }
 
 bool EventDevice::HoverSupported() {
-  return HasEventBit(0, EV_ABS) && HasEventBit(EV_ABS, ABS_MT_DISTANCE);
+  // Multitouch hover uses just the ABS_MT_DISTANCE event in addition to
+  // the normal multi-touch events.
+  if (HasEventBit(0, EV_ABS) && HasEventBit(EV_ABS, ABS_MT_DISTANCE))
+    return true;
+
+  // Simple single-touch hover presence-only detection uses 3 events:
+  // ABS_DISTANCE, BTN_TOUCH, and BTN_TOOL_FINGER.
+  if (HasEventBit(0, EV_ABS) && HasEventBit(EV_ABS, ABS_DISTANCE) &&
+      HasEventBit(0, EV_KEY) && HasEventBit(EV_KEY, BTN_TOUCH) &&
+      HasEventBit(EV_KEY, BTN_TOOL_FINGER))
+    return true;
+
+  return false;
 }
 
 bool EventDevice::HasLeftButton() {
diff --git a/power_manager/powerd/system/input_watcher.cc b/power_manager/powerd/system/input_watcher.cc
index 76adc9e..f7ee948 100644
--- a/power_manager/powerd/system/input_watcher.cc
+++ b/power_manager/powerd/system/input_watcher.cc
@@ -116,6 +116,8 @@
       hovering_(false),
       current_multitouch_slot_(0),
       multitouch_slots_hover_state_(0),
+      single_touch_hover_valid_(false),
+      single_touch_hover_distance_nonzero_(false),
       power_button_to_skip_(kPowerButtonToSkip),
       console_fd_(-1),
       udev_(nullptr),
@@ -373,12 +375,26 @@
       else
         multitouch_slots_hover_state_ &= ~slot_bit;
     }
+  } else if (event.type == EV_ABS && event.code == ABS_DISTANCE) {
+    // For single-touch presence-only hover touchpads, ABS_DISTANCE indicates
+    // the distance above the pad the single-touch finger is hovering
+    VLOG(2) << "ABS_DISTANCE " << event.value;
+    single_touch_hover_distance_nonzero_ = (event.value > 0);
+  } else if (event.type == EV_KEY && event.code == BTN_TOOL_FINGER) {
+    // For single-touch presence-only hover touchpads, BTN_TOOL_FINGER tells
+    // us if the single-touch contact is valid (if we should believe the
+    // value in ABS_DISTANCE)
+    VLOG(2) << "BTN_TOOL_FINGER " << event.value;
+    single_touch_hover_valid_ = (event.value == 1);
   } else if (event.type == EV_SYN && event.code == SYN_REPORT) {
     // SYN_REPORT events indicate the end of the current set of multitouch data.
     // Check whether the overall hovering state is different from before and
     // notify observers if so.
     VLOG(2) << "SYN_REPORT";
-    bool hovering = multitouch_slots_hover_state_ != 0;
+    bool multi_touch_hovering = multitouch_slots_hover_state_ != 0;
+    bool single_touch_hovering = (single_touch_hover_distance_nonzero_ &&
+                                  single_touch_hover_valid_);
+    bool hovering = multi_touch_hovering || single_touch_hovering;
     if (hovering != hovering_) {
       VLOG(1) << "Notifying observers about hover state change to "
               << (hovering ? "on" : "off");
diff --git a/power_manager/powerd/system/input_watcher.h b/power_manager/powerd/system/input_watcher.h
index de4d46a..b1e4177 100644
--- a/power_manager/powerd/system/input_watcher.h
+++ b/power_manager/powerd/system/input_watcher.h
@@ -173,6 +173,13 @@
   // hover event above the touchpad or a touch event on the touchpad.
   uint64_t multitouch_slots_hover_state_;
 
+  // Some touch devices only provide a binary hover value for the whole sensor
+  // instead of the signals by finger.  These variables track that hover
+  // state when it's not tied to a specific slot by using btn_tool_finger to
+  // confirm that the abs_distance value is valid.
+  bool single_touch_hover_valid_;
+  bool single_touch_hover_distance_nonzero_;
+
   // (Events, DeviceType-bitfield) tuples read from |lid_device_| by
   // QueryLidState() that haven't yet been sent to observers.
   std::vector<std::pair<input_event, uint32_t>> queued_events_;
diff --git a/power_manager/powerd/system/input_watcher_unittest.cc b/power_manager/powerd/system/input_watcher_unittest.cc
index 7d1006b..effd473 100644
--- a/power_manager/powerd/system/input_watcher_unittest.cc
+++ b/power_manager/powerd/system/input_watcher_unittest.cc
@@ -316,7 +316,7 @@
   EXPECT_EQ(TABLET_MODE_ON, input_watcher_->GetTabletMode());
 }
 
-TEST_F(InputWatcherTest, Hover) {
+TEST_F(InputWatcherTest, HoverMultitouch) {
   linked_ptr<EventDeviceStub> touchpad(new EventDeviceStub);
   touchpad->set_debug_name("touchpad");
   touchpad->set_hover_supported(true);
@@ -390,6 +390,72 @@
   EXPECT_EQ(kNoActions, observer_->GetActions());
 }
 
+TEST_F(InputWatcherTest, HoverSingletouch) {
+  linked_ptr<EventDeviceStub> touchpad(new EventDeviceStub);
+  touchpad->set_debug_name("touchpad");
+  touchpad->set_hover_supported(true);
+  touchpad->set_has_left_button(true);
+  AddDevice("event0", touchpad);
+
+  linked_ptr<EventDeviceStub> touchscreen(new EventDeviceStub);
+  touchscreen->set_debug_name("touchscreen");
+  touchscreen->set_hover_supported(true);
+  touchscreen->set_has_left_button(false);
+  AddDevice("event1", touchscreen);
+
+  detect_hover_pref_ = 1;
+  Init();
+
+  // Show a finger approaching the pad, but not touching it yet.
+  touchpad->AppendEvent(EV_ABS, ABS_DISTANCE, 1);
+  touchpad->AppendEvent(EV_KEY, BTN_TOOL_FINGER, 1);
+  touchpad->NotifyAboutEvents();
+  EXPECT_EQ(kNoActions, observer_->GetActions());
+
+  // After a SYN_REPORT indicating the end of the current report, hovering
+  // should be reported.
+  touchpad->AppendEvent(EV_SYN, SYN_REPORT, 0);
+  touchpad->NotifyAboutEvents();
+  EXPECT_EQ(kHoverOnAction, observer_->GetActions());
+
+  // Invalidate the hovering finger (leaving without touching the pad at
+  // all) which should turn hover off.
+  touchpad->AppendEvent(EV_KEY, BTN_TOOL_FINGER, 0);
+  touchpad->AppendEvent(EV_SYN, SYN_REPORT, 0);
+  touchpad->NotifyAboutEvents();
+  EXPECT_EQ(kHoverOffAction, observer_->GetActions());
+
+  // Report The finger coming back, but actually touching this time.
+  touchpad->AppendEvent(EV_ABS, ABS_MT_SLOT, 1);
+  touchpad->AppendEvent(EV_ABS, ABS_MT_TRACKING_ID, 1);
+  touchpad->AppendEvent(EV_ABS, ABS_MT_POSITION_X, 100);
+  touchpad->AppendEvent(EV_ABS, ABS_MT_POSITION_Y, 100);
+  touchpad->AppendEvent(EV_ABS, ABS_MT_PRESSURE, 50);
+  touchpad->AppendEvent(EV_KEY, BTN_TOOL_FINGER, 1);
+  touchpad->AppendEvent(EV_KEY, BTN_TOUCH, 1);
+  touchpad->AppendEvent(EV_SYN, SYN_REPORT, 0);
+  touchpad->AppendEvent(EV_ABS, ABS_DISTANCE, 0);
+  touchpad->AppendEvent(EV_SYN, SYN_REPORT, 0);
+  touchpad->NotifyAboutEvents();
+  EXPECT_EQ(kHoverOnAction, observer_->GetActions());
+
+  // Finger leaving the pad now.
+  touchpad->AppendEvent(EV_ABS, ABS_MT_TRACKING_ID, -1);
+  touchpad->AppendEvent(EV_KEY, BTN_TOOL_FINGER, 0);
+  touchpad->AppendEvent(EV_SYN, SYN_REPORT, 0);
+  touchpad->NotifyAboutEvents();
+  EXPECT_EQ(kHoverOffAction, observer_->GetActions());
+
+  // The touchpad should be ignored when the pref is set to false.
+  detect_hover_pref_ = 0;
+  Init();
+  touchpad->AppendEvent(EV_ABS, ABS_DISTANCE, 1);
+  touchpad->AppendEvent(EV_KEY, BTN_TOOL_FINGER, 1);
+  touchpad->AppendEvent(EV_SYN, SYN_REPORT, 0);
+  touchpad->NotifyAboutEvents();
+  EXPECT_EQ(kNoActions, observer_->GetActions());
+}
+
 TEST_F(InputWatcherTest, IgnoreDevices) {
   // Create a device that looks like a power button but that doesn't follow the
   // expected device naming scheme. InputWatcher shouldn't request eents from