From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 873EBC33CAF for ; Thu, 16 Jan 2020 23:28:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 55944206D9 for ; Thu, 16 Jan 2020 23:28:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579217289; bh=101cqP0KzlxnkRcjGmNRCeYL9xUc37fL65nI2lSgZso=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ci350/W/ylJFFFOcziyPrrDikMVflLQMZgT4EyeelZjUAjEcv6X0zYrhg0YCwpy++ X/j8FBfxHn/wOovw6wr2wAZXwf0+RDzl61W99zRxYymIk1ZAiL7L2VFGP2/BtNH1c3 ZoxZTm8awZoaa6lFzidvZ4hUVqkAYM1BNPbUPs0Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391051AbgAPX2H (ORCPT ); Thu, 16 Jan 2020 18:28:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:60554 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389219AbgAPX2E (ORCPT ); Thu, 16 Jan 2020 18:28:04 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B840A20684; Thu, 16 Jan 2020 23:28:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579217284; bh=101cqP0KzlxnkRcjGmNRCeYL9xUc37fL65nI2lSgZso=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QkVqJtX/EYze+ZxLdWT0439N7NlwU/1PX4LtHMhhD5867fBdMRk/u4KSBZFxg0OBK 4NcsxW341lC+G/nvxCB0LMNIlOmogZKM/BVgAmYee4zq6wyC2wg8KEMjLWa66IFXJ6 V1uzimty5Dmiyd9ofgk7eviyJOQoOmF6k7MMJIxQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marcel Holtmann , Jiri Kosina , Sasha Levin Subject: [PATCH 4.19 02/84] HID: hidraw: Fix returning EPOLLOUT from hidraw_poll Date: Fri, 17 Jan 2020 00:17:36 +0100 Message-Id: <20200116231713.508100390@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200116231713.087649517@linuxfoundation.org> References: <20200116231713.087649517@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marcel Holtmann [ Upstream commit 9f3b61dc1dd7b81e99e7ed23776bb64a35f39e1a ] 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 Signed-off-by: Sasha Levin --- drivers/hid/hidraw.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index c75b66d58636..a025b6961896 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -260,10 +260,10 @@ 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) -- 2.20.1