Merge branches 'for-3.18/always-poll-quirk', 'for-3.18/logitech', 'for-3.18/picolcd...

[pandora-kernel.git] / drivers / hid / hid-rmi.c

diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c
index 8389e81..3cccff7 100644 (file)
--- a/drivers/hid/hid-rmi.c
+++ b/drivers/hid/hid-rmi.c
@@ -320,10 +320,7 @@ static int rmi_f11_input_event(struct hid_device *hdev, u8 irq, u8 *data,
        int offset;
        int i;
 
-       if (size < hdata->f11.report_size)
-               return 0;
-
-       if (!(irq & hdata->f11.irq_mask))
+       if (!(irq & hdata->f11.irq_mask) || size <= 0)
                return 0;
 
        offset = (hdata->max_fingers >> 2) + 1;
@@ -332,9 +329,19 @@ static int rmi_f11_input_event(struct hid_device *hdev, u8 irq, u8 *data,
                int fs_bit_position = (i & 0x3) << 1;
                int finger_state = (data[fs_byte_position] >> fs_bit_position) &
                                        0x03;
+               int position = offset + 5 * i;
+
+               if (position + 5 > size) {
+                       /* partial report, go on with what we received */
+                       printk_once(KERN_WARNING
+                               "%s %s: Detected incomplete finger report. Finger reports may occasionally get dropped on this platform.\n",
+                                dev_driver_string(&hdev->dev),
+                                dev_name(&hdev->dev));
+                       hid_dbg(hdev, "Incomplete finger report\n");
+                       break;
+               }
 
-               rmi_f11_process_touch(hdata, i, finger_state,
-                               &data[offset + 5 * i]);
+               rmi_f11_process_touch(hdata, i, finger_state, &data[position]);
        }
        input_mt_sync_frame(hdata->input);
        input_sync(hdata->input);
@@ -352,6 +359,11 @@ static int rmi_f30_input_event(struct hid_device *hdev, u8 irq, u8 *data,
        if (!(irq & hdata->f30.irq_mask))
                return 0;
 
+       if (size < (int)hdata->f30.report_size) {
+               hid_warn(hdev, "Click Button pressed, but the click data is missing\n");
+               return 0;
+       }
+
        for (i = 0; i < hdata->gpio_led_count; i++) {
                if (test_bit(i, &hdata->button_mask)) {
                        value = (data[i / 8] >> (i & 0x07)) & BIT(0);
@@ -412,9 +424,29 @@ static int rmi_read_data_event(struct hid_device *hdev, u8 *data, int size)
        return 1;
 }
 
+static int rmi_check_sanity(struct hid_device *hdev, u8 *data, int size)
+{
+       int valid_size = size;
+       /*
+        * On the Dell XPS 13 9333, the bus sometimes get confused and fills
+        * the report with a sentinel value "ff". Synaptics told us that such
+        * behavior does not comes from the touchpad itself, so we filter out
+        * such reports here.
+        */
+
+       while ((data[valid_size - 1] == 0xff) && valid_size > 0)
+               valid_size--;
+
+       return valid_size;
+}
+
 static int rmi_raw_event(struct hid_device *hdev,
                struct hid_report *report, u8 *data, int size)
 {
+       size = rmi_check_sanity(hdev, data, size);
+       if (size < 2)
+               return 0;
+
        switch (data[0]) {
        case RMI_READ_DATA_REPORT_ID:
                return rmi_read_data_event(hdev, data, size);