1 files changed, 14 insertions, 2 deletions

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 40fbb7c52723..88da991ef256 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -1375,7 +1375,8 @@ static bool mt_need_to_apply_feature(struct hid_device *hdev,
                                      struct hid_usage *usage,
                                      enum latency_mode latency,
                                      bool surface_switch,
-                                     bool button_switch)
+                                     bool button_switch,
+                                     bool *inputmode_found)
 {
         struct mt_device *td = hid_get_drvdata(hdev);
         struct mt_class *cls = &td->mtclass;
@@ -1387,6 +1388,14 @@ static bool mt_need_to_apply_feature(struct hid_device *hdev,
 
         switch (usage->hid) {
         case HID_DG_INPUTMODE:
+                /*
+                 * Some elan panels wrongly declare 2 input mode features,
+                 * and silently ignore when we set the value in the second
+                 * field. Skip the second feature and hope for the best.
+                 */
+                if (*inputmode_found)
+                        return false;
+
                 if (cls->quirks & MT_QUIRK_FORCE_GET_FEATURE) {
                         report_len = hid_report_len(report);
                         buf = hid_alloc_report_buf(report, GFP_KERNEL);
@@ -1402,6 +1411,7 @@ static bool mt_need_to_apply_feature(struct hid_device *hdev,
                 }
 
                 field->value[index] = td->inputmode_value;
+                *inputmode_found = true;
                 return true;
 
         case HID_DG_CONTACTMAX:
@@ -1439,6 +1449,7 @@ static void mt_set_modes(struct hid_device *hdev, enum latency_mode latency,
         struct hid_usage *usage;
         int i, j;
         bool update_report;
+        bool inputmode_found = false;
 
         rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
         list_for_each_entry(rep, &rep_enum->report_list, list) {
@@ -1457,7 +1468,8 @@ static void mt_set_modes(struct hid_device *hdev, enum latency_mode latency,
                                                              usage,
                                                              latency,
                                                              surface_switch,
-                                                             button_switch))
+                                                             button_switch,
+                                                             &inputmode_found))
                                         update_report = true;
                         }
                 }