HID: rmi: make transfer buffers DMA capable

Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove
buffers allocated on the stack.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-rmi.c

@@ -188,10 +188,16 @@ static int rmi_set_page(struct hid_device *hdev, u8 page)
 static int rmi_set_mode(struct hid_device *hdev, u8 mode)
 {
 	int ret;
-	u8 txbuf[2] = {RMI_SET_RMI_MODE_REPORT_ID, mode};
+	const u8 txbuf[2] = {RMI_SET_RMI_MODE_REPORT_ID, mode};
+	u8 *buf;
 
-	ret = hid_hw_raw_request(hdev, RMI_SET_RMI_MODE_REPORT_ID, txbuf,
+	buf = kmemdup(txbuf, sizeof(txbuf), GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = hid_hw_raw_request(hdev, RMI_SET_RMI_MODE_REPORT_ID, buf,
 			sizeof(txbuf), HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+	kfree(buf);
 	if (ret < 0) {
 		dev_err(&hdev->dev, "unable to set rmi mode to %d (%d)\n", mode,
 			ret);