From ae545017ff74ffe09d52909228510da85852b789 Mon Sep 17 00:00:00 2001 From: Fabian Henneke Date: Tue, 9 Jul 2019 13:03:37 +0200 Subject: [PATCH] hidraw: Return EPOLLOUT from hidraw_poll [ Upstream commit 378b80370aa1fe50f9c48a3ac8af3e416e73b89f ] Always return EPOLLOUT from hidraw_poll when a device is connected. This is safe since writes are always possible (but will always block). hidraw does not support non-blocking writes and instead always calls blocking backend functions on write requests. Hence, so far, a call to poll never returned EPOLLOUT, which confuses tools like socat. Signed-off-by: Fabian Henneke In-reply-to: Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/hidraw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index 627a24d3ea7c..27d2f5a48a11 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -265,7 +265,7 @@ static unsigned int hidraw_poll(struct file *file, poll_table *wait) poll_wait(file, &list->hidraw->wait, wait); if (list->head != list->tail) - return POLLIN | POLLRDNORM; + return POLLIN | POLLRDNORM | POLLOUT; if (!list->hidraw->exist) return POLLERR | POLLHUP; return 0;