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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65CB0C433EF for ; Wed, 3 Nov 2021 17:18:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D10560F02 for ; Wed, 3 Nov 2021 17:18:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231298AbhKCRUj (ORCPT ); Wed, 3 Nov 2021 13:20:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231305AbhKCRUi (ORCPT ); Wed, 3 Nov 2021 13:20:38 -0400 Received: from mail-wm1-x334.google.com (mail-wm1-x334.google.com [IPv6:2a00:1450:4864:20::334]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B68D9C061203 for ; Wed, 3 Nov 2021 10:18:01 -0700 (PDT) Received: by mail-wm1-x334.google.com with SMTP id y196so2556689wmc.3 for ; Wed, 03 Nov 2021 10:18:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=QmVc9Je73rZQ/JXi2kSeHK45robtjQUCtsTvhzPdR/Q=; b=f1kzxmILHxk6ryEldtMA/STMiylac96ou/kUudthn9UoTm1IWCCwnmHEwKaBbm+mrk qG0XG8lcutYXlOXFoi8GSwcV1qKdrVA/KNM4K2Ba2aPGJbQo38gReTEG8jt1cvhLA/3A uNtFn0QgRGcvb0zOkD6TQsvAcG3NDbyjcOw9XaydNhzLKEQOB4DAtxDs+BqP6N9bSmoV vfTiDSVUnLTyP/U5b0swS3Ih2G9wzRztSRqCTaJ4fIjtuOg5a6/0Rm8lLKITUfMZPRg8 6KgBA8zosImuHahkRQi9Q0ecFSEw+RWytxDe9DBpsu3UFSfm1owaO+sPWVRLBF9u1ScQ GDBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=QmVc9Je73rZQ/JXi2kSeHK45robtjQUCtsTvhzPdR/Q=; b=GSRfx0oh4iy9zC4E4cCf1ZqKwhcGkVVgPim3l0n2ng0ppK/ISVMNv0Nstltr/GRfJR eS+R5/rxXLcWSxtBVp534NNTksF0UY9qBf5aJIWw8JFuiwJpDTZoBllfTEQO9b78P+z3 l9pHBC3VtCxBPNMxmWgp2ouA7AIJhBq6GvlTUjtrsZBr5xLI3K3RJ/VwmZz5utaN49GS NFMfOKMOOuxjcCEQ5VlUHJItczOkDTQU745VXuodqImUqxyhjflAyYRPVt5Mh/J4Iyoc J2b6Dilk7Hy36DSG3l5MG9k+3/6rS4Faybkp1vF/pZBXx2oe8mXNNSKar2jtXMFKcFeR Iglw== X-Gm-Message-State: AOAM533AsVt8Ff0wbp4wMSwtfbB8TYMxqhO8MTUQFqVxl+qnhMBA909Q MUzGeIn0rYZObnYm8IouxnYBSQ== X-Google-Smtp-Source: ABdhPJytEVA3WQjrHJG2sA/bxnMXKTuDgE7l0CN2G/o7J4Vi5JAQr4pbv0uZCl/6aR4hMNxR40Tmlg== X-Received: by 2002:a1c:9dc7:: with SMTP id g190mr17055937wme.130.1635959880277; Wed, 03 Nov 2021 10:18:00 -0700 (PDT) Received: from maple.lan (cpc141216-aztw34-2-0-cust174.18-1.cable.virginm.net. [80.7.220.175]) by smtp.gmail.com with ESMTPSA id b10sm2637233wrt.36.2021.11.03.10.17.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Nov 2021 10:17:57 -0700 (PDT) Date: Wed, 3 Nov 2021 17:17:56 +0000 From: Daniel Thompson To: Hans de Goede Cc: Lee Jones , Jingoo Han , Tsuchiya Yuto , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/3] backlight: lp855x: Add support ACPI enumeration Message-ID: <20211103171756.wxthncse2f4syeiz@maple.lan> References: <20211102225504.18920-1-hdegoede@redhat.com> <20211102225504.18920-3-hdegoede@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211102225504.18920-3-hdegoede@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 02, 2021 at 11:55:04PM +0100, Hans de Goede wrote: > The Xiaomi Mi Pad 2 tablet uses an ACPI enumerated LP8556 backlight > controller for its LCD-panel, with a Xiaomi specific ACPI HID of > "XMCC0001", add support for this. > > Note the new "if (id)" check also fixes a NULL pointer deref when a user > tries to manually bind the driver from sysfs. > > When CONFIG_ACPI is disabled acpi_match_device() will always return NULL, > so the lp855x_parse_acpi() call will get optimized away. > > Signed-off-by: Hans de Goede Reviewed-by: Daniel Thompson Daniel.