From 4f20b7beca5a183139b22ed4fdfc161396452426 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Tue, 1 Dec 2020 13:44:46 +0100 Subject: [PATCH] media: cec: add EPOLLPRI in poll() when dev is unregistered If the CEC device was unregistered, then add EPOLLPRI to the poll() mask. Otherwise a select() that only waits for exceptions will not wake up. A select() that waits for read and/or write events *will* wake up on an EPOLLERR, but not (for some reason) if it just waits for exceptions. Strangly the epoll functionality will wakeup on EPOLLERR if you just wait for an exception, so in this respect select() and epoll differ. In the end it doesn't really matter, what matters is that polling file handles are woken up on device unregistration. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/cec/core/cec-api.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/cec/core/cec-api.c b/drivers/media/cec/core/cec-api.c index f922a2196b2b..769e6b4cddce 100644 --- a/drivers/media/cec/core/cec-api.c +++ b/drivers/media/cec/core/cec-api.c @@ -40,7 +40,7 @@ static __poll_t cec_poll(struct file *filp, poll_wait(filp, &fh->wait, poll); if (!cec_is_registered(adap)) - return EPOLLERR | EPOLLHUP; + return EPOLLERR | EPOLLHUP | EPOLLPRI; mutex_lock(&adap->lock); if (adap->is_configured && adap->transmit_queue_sz < CEC_MAX_MSG_TX_QUEUE_SZ)