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=unavailable 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 76DAFC2D0DB for ; Wed, 22 Jan 2020 09:54:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41D162465A for ; Wed, 22 Jan 2020 09:54:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579686889; bh=OQx+HUceJcnoMODpA+j8l5bsP7KYSCFPs+XvV5ngFKE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=H9ejVSWdlMBZSv4EjD7ZG8WWZyJzH5LkiuESf/JFCXO9+0fyZIjpmuownDAc0LQDC QlCE8tEcTgKELGZwWgPm+oBPTw5B8xgH30ZNVA1vjz6oygVcYlp8DPi8pclF9SA1ww DKrXYEIVA128eDtEGqyHC0RvZoL88UTZjugOKlJU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730005AbgAVJdo (ORCPT ); Wed, 22 Jan 2020 04:33:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:47738 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729691AbgAVJdo (ORCPT ); Wed, 22 Jan 2020 04:33:44 -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 037702071E; Wed, 22 Jan 2020 09:33:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579685623; bh=OQx+HUceJcnoMODpA+j8l5bsP7KYSCFPs+XvV5ngFKE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pW+Aymy0DD8j17su+v7LWHJqrsqRJ8yuiJ7JUaVY4g1mnmhZNtlt5tIvjTxDVU+FR bWFRnEc4MvE++Gly1mjJR9W72kwpttb/8Z9fgA8/UdC1DfmMR6vGqRMtD888kML4yp 2dreBORfvkeH/BV0EBwJaY7tAYDGA8dHyrsQngbU= 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 4.9 02/97] HID: hidraw: Fix returning EPOLLOUT from hidraw_poll Date: Wed, 22 Jan 2020 10:28:06 +0100 Message-Id: <20200122092756.076054156@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200122092755.678349497@linuxfoundation.org> References: <20200122092755.678349497@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 225456c1a39a..290f7f7817d3 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -260,10 +260,10 @@ 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 | POLLOUT; + return POLLIN | POLLRDNORM; if (!list->hidraw->exist) return POLLERR | POLLHUP; - return 0; + return POLLOUT | POLLWRNORM; } static int hidraw_open(struct inode *inode, struct file *file) -- 2.20.1