From patchwork Fri Jun 16 07:35:39 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 9790781 X-Patchwork-Delegate: andy.shevchenko@gmail.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0C8DE60326 for ; Fri, 16 Jun 2017 07:35:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0154D283E8 for ; Fri, 16 Jun 2017 07:35:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E77D32841D; Fri, 16 Jun 2017 07:35:58 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7D568283E8 for ; Fri, 16 Jun 2017 07:35:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752375AbdFPHf5 (ORCPT ); Fri, 16 Jun 2017 03:35:57 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:48093 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752124AbdFPHf5 (ORCPT ); Fri, 16 Jun 2017 03:35:57 -0400 Received: from [175.41.48.77] (helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1dLlnK-0001nA-Ur; Fri, 16 Jun 2017 07:35:51 +0000 From: Kai-Heng Feng To: pali.rohar@gmail.com Cc: mjg59@srcf.ucam.org, dvhart@infradead.org, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, Kai-Heng Feng Subject: [PATCH] platform/x86: dell-laptop: Fix bogus keyboard backlight sysfs interface Date: Fri, 16 Jun 2017 15:35:39 +0800 Message-Id: <20170616073539.1185-1-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.13.1 Sender: platform-driver-x86-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Dell Latitude 3160 does not have keyboard backlight, but there is a sysfs interface for it, which does nothing at all. KBD_LED_OFF_TOKEN is the only token can be found. Since it doesn't have KBD_LED_ON_TOKEN or KBD_LED_AUTO_*_TOKEN, it should be safe to assume it does not support keyboard backlight. Reports keyboard backlight is supported only when tokens other than KBD_LED_OFF_TOKEN can be found. Signed-off-by: Kai-Heng Feng --- drivers/platform/x86/dell-laptop.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c index ec202094bd50..743d7ce8c0c8 100644 --- a/drivers/platform/x86/dell-laptop.c +++ b/drivers/platform/x86/dell-laptop.c @@ -1510,7 +1510,11 @@ static void kbd_init(void) ret = kbd_init_info(); kbd_init_tokens(); - if (kbd_token_bits != 0 || ret == 0) + /* + * If KBD_LED_OFF_TOKEN is the only token, + * consider there is no keyboard backlight. + */ + if ((kbd_token_bits & ~BIT(5)) != 0 || ret == 0) kbd_led_present = true; }