From: Marcel Holtmann Date: Wed, 4 Dec 2019 02:37:13 +0000 (+0100) Subject: HID: hidraw: Fix returning EPOLLOUT from hidraw_poll X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=9f3b61dc1dd7b81e99e7ed23776bb64a35f39e1a;p=uclinux-h8%2Flinux.git HID: hidraw: Fix returning EPOLLOUT from hidraw_poll When polling a connected /dev/hidrawX device, it is useful to get the EPOLLOUT when writing is possible. Since writing is possible as soon as the device is connected, always return it. Right now EPOLLOUT is only returned when there are also input reports are available. This works if devices start sending reports when connected, but some HID devices might need an output report first before sending any input reports. This change will allow using EPOLLOUT here as well. Fixes: 378b80370aa1 ("hidraw: Return EPOLLOUT from hidraw_poll") Signed-off-by: Marcel Holtmann Cc: stable@vger.kernel.org Signed-off-by: Jiri Kosina --- diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index c3fc0ceb8096..f61f2123a755 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -252,10 +252,10 @@ static __poll_t hidraw_poll(struct file *file, poll_table *wait) poll_wait(file, &list->hidraw->wait, wait); if (list->head != list->tail) - return EPOLLIN | EPOLLRDNORM | EPOLLOUT; + return EPOLLIN | EPOLLRDNORM; if (!list->hidraw->exist) return EPOLLERR | EPOLLHUP; - return 0; + return EPOLLOUT | EPOLLWRNORM; } static int hidraw_open(struct inode *inode, struct file *file)