HID: magicmouse: ignore 'ivalid report id' while switching modes

Jiri Kosina · Jiri Kosina · commit 23746a66d7d9 · 2011-05-20T10:28:00.000+02:00
The device reponds with 'invalid report id' when feature report switching it into multitouch mode is sent to it. This has been silently ignored before 0825411 ("HID: bt: Wait for ACK on Sent Reports"), but since this commit, it propagates -EIO from the _raw callback . So let the driver ignore -EIO as response to 0xd7,0x01 report, as that's how the device reacts in normal mode. Sad, but following reality. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=35022 Tested-by: Chase Douglas <chase.douglas@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-magicmouse.c b/drivers/hid/hid-magicmouse.c
@@ -499,9 +499,17 @@ static int magicmouse_probe(struct hid_device *hdev,
 	}
 	report->size = 6;
 
+	/*
+	 * The device reponds with 'invalid report id' when feature
+	 * report switching it into multitouch mode is sent to it.
+	 *
+	 * This results in -EIO from the _raw low-level transport callback,
+	 * but there seems to be no other way of switching the mode.
+	 * Thus the super-ugly hacky success check below.
+	 */
 	ret = hdev->hid_output_raw_report(hdev, feature, sizeof(feature),
 			HID_FEATURE_REPORT);
-	if (ret != sizeof(feature)) {
+	if (ret != -EIO) {
 		hid_err(hdev, "unable to request touch data (%d)\n", ret);
 		goto err_stop_hw;
 	}
