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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 1C2C1C3A5A2 for ; Fri, 20 Sep 2019 14:37:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F1F2420B7C for ; Fri, 20 Sep 2019 14:37:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392846AbfITOho (ORCPT ); Fri, 20 Sep 2019 10:37:44 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35784 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388032AbfITOZA (ORCPT ); Fri, 20 Sep 2019 10:25:00 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iBJqD-0004xB-VW; Fri, 20 Sep 2019 15:24:58 +0100 Received: from ben by deadeye with local (Exim 4.92.1) (envelope-from ) id 1iBJqD-0007r8-1Z; Fri, 20 Sep 2019 15:24:57 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Guenter Roeck" Date: Fri, 20 Sep 2019 15:23:35 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 032/132] hwmon: (w83627hf) Use request_muxed_region for Super-IO accesses In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.74-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Guenter Roeck commit e95fd518d05bfc087da6fcdea4900a57cfb083bd upstream. Super-IO accesses may fail on a system with no or unmapped LPC bus. Also, other drivers may attempt to access the LPC bus at the same time, resulting in undefined behavior. Use request_muxed_region() to ensure that IO access on the requested address space is supported, and to ensure that access by multiple drivers is synchronized. Fixes: b72656dbc491 ("hwmon: (w83627hf) Stop using globals for I/O port numbers") Signed-off-by: Guenter Roeck Signed-off-by: Ben Hutchings --- drivers/hwmon/w83627hf.c | 42 +++++++++++++++++++++++++++++++++++----- 1 file changed, 37 insertions(+), 5 deletions(-) --- a/drivers/hwmon/w83627hf.c +++ b/drivers/hwmon/w83627hf.c @@ -130,17 +130,23 @@ superio_select(struct w83627hf_sio_data outb(ld, sio->sioaddr + 1); } -static inline void +static inline int superio_enter(struct w83627hf_sio_data *sio) { + if (!request_muxed_region(sio->sioaddr, 2, DRVNAME)) + return -EBUSY; + outb(0x87, sio->sioaddr); outb(0x87, sio->sioaddr); + + return 0; } static inline void superio_exit(struct w83627hf_sio_data *sio) { outb(0xAA, sio->sioaddr); + release_region(sio->sioaddr, 2); } #define W627_DEVID 0x52 @@ -1273,7 +1279,7 @@ static DEVICE_ATTR(name, S_IRUGO, show_n static int __init w83627hf_find(int sioaddr, unsigned short *addr, struct w83627hf_sio_data *sio_data) { - int err = -ENODEV; + int err; u16 val; static __initconst char *const names[] = { @@ -1285,7 +1291,11 @@ static int __init w83627hf_find(int sioa }; sio_data->sioaddr = sioaddr; - superio_enter(sio_data); + err = superio_enter(sio_data); + if (err) + return err; + + err = -ENODEV; val = force_id ? force_id : superio_inb(sio_data, DEVID); switch (val) { case W627_DEVID: @@ -1639,9 +1649,21 @@ static int w83627thf_read_gpio5(struct p struct w83627hf_sio_data *sio_data = dev_get_platdata(&pdev->dev); int res = 0xff, sel; - superio_enter(sio_data); + if (superio_enter(sio_data)) { + /* + * Some other driver reserved the address space for itself. + * We don't want to fail driver instantiation because of that, + * so display a warning and keep going. + */ + dev_warn(&pdev->dev, + "Can not read VID data: Failed to enable SuperIO access\n"); + return res; + } + superio_select(sio_data, W83627HF_LD_GPIO5); + res = 0xff; + /* Make sure these GPIO pins are enabled */ if (!(superio_inb(sio_data, W83627THF_GPIO5_EN) & (1<<3))) { dev_dbg(&pdev->dev, "GPIO5 disabled, no VID function\n"); @@ -1672,7 +1694,17 @@ static int w83687thf_read_vid(struct pla struct w83627hf_sio_data *sio_data = dev_get_platdata(&pdev->dev); int res = 0xff; - superio_enter(sio_data); + if (superio_enter(sio_data)) { + /* + * Some other driver reserved the address space for itself. + * We don't want to fail driver instantiation because of that, + * so display a warning and keep going. + */ + dev_warn(&pdev->dev, + "Can not read VID data: Failed to enable SuperIO access\n"); + return res; + } + superio_select(sio_data, W83627HF_LD_HWM); /* Make sure these GPIO pins are enabled */