From: Marcel Holtmann <marcel@holtmann.org>
Date: Wed, 4 Dec 2019 02:43:55 +0000 (+0100)
Subject: HID: uhid: Fix returning EPOLLOUT from uhid_char_poll
X-Git-Tag: v3.16.83~174
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5113ebdbf286156689d2d55efb0588bebc6c3dcf;p=thirdparty%2Fkernel%2Fstable.git

HID: uhid: Fix returning EPOLLOUT from uhid_char_poll

commit be54e7461ffdc5809b67d2aeefc1ddc9a91470c7 upstream.

Always return EPOLLOUT from uhid_char_poll to allow polling /dev/uhid
for writable state.

Fixes: 1f9dec1e0164 ("HID: uhid: allow poll()'ing on uhid devices")
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 3.16: s/EPOLL/POLL/g]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c
index 035c7c2863dc3..796b498993eb9 100644
--- a/drivers/hid/uhid.c
+++ b/drivers/hid/uhid.c
@@ -726,7 +726,7 @@ static unsigned int uhid_char_poll(struct file *file, poll_table *wait)
 	if (uhid->head != uhid->tail)
 		return POLLIN | POLLRDNORM;
 
-	return 0;
+	return POLLOUT | POLLWRNORM;
 }
 
 static const struct file_operations uhid_fops = {