1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/input/sparse-keymap.c b/drivers/input/sparse-keymap.c
index 337bf51bc984..fdb6a3976f94 100644
--- a/drivers/input/sparse-keymap.c
+++ b/drivers/input/sparse-keymap.c
@@ -208,6 +208,12 @@ int sparse_keymap_setup(struct input_dev *dev,
                 }
         }
 
+        if (test_bit(EV_KEY, dev->evbit)) {
+                __set_bit(KEY_UNKNOWN, dev->keybit);
+                __set_bit(EV_MSC, dev->evbit);
+                __set_bit(MSC_SCAN, dev->mscbit);
+        }
+
         dev->keycode = map;
         dev->keycodemax = map_size;
         dev->getkeycode = sparse_keymap_getkeycode;
@@ -268,6 +274,7 @@ void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *k
 {
         switch (ke->type) {
         case KE_KEY:
+                input_event(dev, EV_MSC, MSC_SCAN, ke->code);
                 input_report_key(dev, ke->keycode, value);
                 input_sync(dev);
                 if (value && autorelease) {
@@ -305,12 +312,19 @@ bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code,
 {
         const struct key_entry *ke =
                 sparse_keymap_entry_from_scancode(dev, code);
+        struct key_entry unknown_ke;
 
         if (ke) {
                 sparse_keymap_report_entry(dev, ke, value, autorelease);
                 return true;
         }
 
+        /* Report an unknown key event as a debugging aid */
+        unknown_ke.type = KE_KEY;
+        unknown_ke.code = code;
+        unknown_ke.keycode = KEY_UNKNOWN;
+        sparse_keymap_report_entry(dev, &unknown_ke, value, true);
+
         return false;
 }
 EXPORT_SYMBOL(sparse_keymap_report_event);