From: Johan Hovold <johan@kernel.org>
Date: Mon, 30 Jan 2017 10:26:39 +0000 (+0100)
Subject: HID: cp2112: fix gpio-callback error handling
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=7396685a1bca323b96fd79b836ae22b7569d7068;p=linux-beck.git

HID: cp2112: fix gpio-callback error handling

commit 8e9faa15469ed7c7467423db4c62aeed3ff4cae3 upstream.

In case of a zero-length report, the gpio direction_input callback would
currently return success instead of an errno.

Fixes: 1ffb3c40ffb5 ("HID: cp2112: make transfer buffers DMA capable")
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index ffc941c40a0f..e06c1344c913 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/drivers/hid/hid-cp2112.c
@@ -206,7 +206,7 @@ static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 
 exit:
 	mutex_unlock(&dev->lock);
-	return ret <= 0 ? ret : -EIO;
+	return ret < 0 ? ret : -EIO;
 }
 
 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)