Merge tag 'fixes-for-v4.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi...

[firefly-linux-kernel-4.4.55.git] / drivers / hid / hid-multitouch.c

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 2ed42d8f805b57dd87273f7413873469ed11faf3..3d664d01305e5ef32301fdcf53a4f3bbee61f027 100644 (file)
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -309,6 +309,41 @@ static struct attribute_group mt_attribute_group = {
        .attrs = sysfs_attrs
 };
 
+static void mt_get_feature(struct hid_device *hdev, struct hid_report *report)
+{
+       struct mt_device *td = hid_get_drvdata(hdev);
+       int ret, size = hid_report_len(report);
+       u8 *buf;
+
+       /*
+        * Only fetch the feature report if initial reports are not already
+        * been retrieved. Currently this is only done for Windows 8 touch
+        * devices.
+        */
+       if (!(hdev->quirks & HID_QUIRK_NO_INIT_REPORTS))
+               return;
+       if (td->mtclass.name != MT_CLS_WIN_8)
+               return;
+
+       buf = hid_alloc_report_buf(report, GFP_KERNEL);
+       if (!buf)
+               return;
+
+       ret = hid_hw_raw_request(hdev, report->id, buf, size,
+                                HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
+       if (ret < 0) {
+               dev_warn(&hdev->dev, "failed to fetch feature %d\n",
+                        report->id);
+       } else {
+               ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, buf,
+                                          size, 0);
+               if (ret)
+                       dev_warn(&hdev->dev, "failed to report feature\n");
+       }
+
+       kfree(buf);
+}
+
 static void mt_feature_mapping(struct hid_device *hdev,
                struct hid_field *field, struct hid_usage *usage)
 {
@@ -327,6 +362,8 @@ static void mt_feature_mapping(struct hid_device *hdev,
 
                break;
        case HID_DG_CONTACTMAX:
+               mt_get_feature(hdev, field->report);
+
                td->maxcontact_report_id = field->report->id;
                td->maxcontacts = field->value[0];
                if (!td->maxcontacts &&
@@ -343,6 +380,7 @@ static void mt_feature_mapping(struct hid_device *hdev,
                        break;
                }
 
+               mt_get_feature(hdev, field->report);
                if (field->value[usage->usage_index] == MT_BUTTONTYPE_CLICKPAD)
                        td->is_buttonpad = true;
 
@@ -976,6 +1014,9 @@ static int mt_input_configured(struct hid_device *hdev, struct hid_input *hi)
                case HID_DG_TOUCHSCREEN:
                        /* we do not set suffix = "Touchscreen" */
                        break;
+               case HID_DG_TOUCHPAD:
+                       suffix = "Touchpad";
+                       break;
                case HID_GD_SYSTEM_CONTROL:
                        suffix = "System Control";
                        break;
@@ -1036,8 +1077,13 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
                 * reports. Fortunately, the Win8 spec says that all touches
                 * should be sent during each report, making the initialization
                 * of input reports unnecessary.
+                *
+                * In addition some touchpads do not behave well if we read
+                * all feature reports from them. Instead we prevent
+                * initial report fetching and then selectively fetch each
+                * report we are interested in.
                 */
-               hdev->quirks |= HID_QUIRK_NO_INIT_INPUT_REPORTS;
+               hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
 
        td = devm_kzalloc(&hdev->dev, sizeof(struct mt_device), GFP_KERNEL);
        if (!td) {