HID: uhid: Fix returning EPOLLOUT from uhid_char_poll

BugLink: https://bugs.launchpad.net/bugs/1862227
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>
Cc: stable@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/hid/uhid.c b/drivers/hid/uhid.c
index fa0cc089982739e9d70da131c7b6235571f0acfa..935c3d0a3b636f63483d88899d0e2012df64126b 100644 (file)
--- a/drivers/hid/uhid.c
+++ b/drivers/hid/uhid.c
@@ -772,7 +772,7 @@ static __poll_t uhid_char_poll(struct file *file, poll_table *wait)
        if (uhid->head != uhid->tail)
                return EPOLLIN | EPOLLRDNORM;
 
-       return 0;
+       return EPOLLOUT | EPOLLWRNORM;
 }
 
 static const struct file_operations uhid_fops = {