From: Fabian Henneke fabian.henneke@gmail.com
[ 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 fabian.henneke@gmail.com In-reply-to: CA+hv5qkyis03CgYTWeWX9cr0my-d2Oe+aZo+mjmWRXgjrGqyrw@mail.gmail.com Signed-off-by: Jiri Kosina jkosina@suse.cz Signed-off-by: Sasha Levin sashal@kernel.org --- 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 5652bd0ffb4d..1ac82e194818 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -260,7 +260,7 @@ 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;