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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61C8CC001B0 for ; Mon, 14 Aug 2023 12:08:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232821AbjHNMIK (ORCPT ); Mon, 14 Aug 2023 08:08:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232699AbjHNMHo (ORCPT ); Mon, 14 Aug 2023 08:07:44 -0400 Received: from wxsgout04.xfusion.com (wxsgout04.xfusion.com [36.139.87.180]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07930DD for ; Mon, 14 Aug 2023 05:07:41 -0700 (PDT) Received: from wuxshcsitd00600.xfusion.com (unknown [10.32.133.213]) by wxsgout04.xfusion.com (SkyGuard) with ESMTPS id 4RPY5N0dxFz9xHjf; Mon, 14 Aug 2023 20:06:00 +0800 (CST) Received: from localhost (10.82.147.3) by wuxshcsitd00600.xfusion.com (10.32.133.213) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Mon, 14 Aug 2023 20:07:17 +0800 Date: Mon, 14 Aug 2023 20:07:17 +0800 From: Wang Jinchao To: Jani Nikula CC: Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Daniel Vetter , , , , Subject: Re: [PATCH] drm/i915: Fix Kconfig error for CONFIG_DRM_I915 Message-ID: References: <87o7jaythm.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <87o7jaythm.fsf@intel.com> X-Originating-IP: [10.82.147.3] X-ClientProxiedBy: wuxshcsitd00601.xfusion.com (10.32.135.241) To wuxshcsitd00600.xfusion.com (10.32.133.213) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 14, 2023 at 10:26:45AM +0300, Jani Nikula wrote: > On Sat, 12 Aug 2023, Wang Jinchao wrote: > > When CONFIG_DRM_I915 is set to 'y' and CONFIG_BACKLIGHT_CLASS_DEVICE > > is set to 'm', we encountered an ld.lld error during the build process: > > > > ld.lld: error: undefined symbol: backlight_device_get_by_name > > >>> referenced by intel_backlight.c:955 > > >>> vmlinux.o:(intel_backlight_device_register) > > > > ld.lld: error: undefined symbol: backlight_device_register > > >>> referenced by intel_backlight.c:971 > > >>> vmlinux.o:(intel_backlight_device_register) > > > > ld.lld: error: undefined symbol: backlight_device_unregister > > >>> referenced by intel_backlight.c:999 > > >>> vmlinux.o:(intel_backlight_device_unregister) > > > > This issue occurred because intel_backlight_device_register and > > intel_backlight_device_unregister were enclosed within > > However, according to Kconfig, CONFIG_DRM_I915 will select > > BACKLIGHT_CLASS_DEVICE only if ACPI is enabled. > > This led to an error, which can be resolved by removing the > > conditional statements related to ACPI. > > The real fix is to use > > depends on BACKLIGHT_CLASS_DEVICE || BACKLIGHT_CLASS_DEVICE=n it works. > > but in order to do that, you need to change a lot of places to depend Why, what are the other places? > on, not select BACKLIGHT_CLASS_DEVICE, because otherwise you end up with got it. > other dependency issues. > > BR, > Jani. > > > > > Signed-off-by: Wang Jinchao > > --- > > drivers/gpu/drm/i915/Kconfig | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig > > index 01b5a8272a27..5003de921bf7 100644 > > --- a/drivers/gpu/drm/i915/Kconfig > > +++ b/drivers/gpu/drm/i915/Kconfig > > @@ -24,7 +24,7 @@ config DRM_I915 > > select IRQ_WORK > > # i915 depends on ACPI_VIDEO when ACPI is enabled > > # but for select to work, need to select ACPI_VIDEO's dependencies, ick > > - select BACKLIGHT_CLASS_DEVICE if ACPI > > + select BACKLIGHT_CLASS_DEVICE > > select INPUT if ACPI > > select X86_PLATFORM_DEVICES if ACPI > > select ACPI_WMI if ACPI > > -- > Jani Nikula, Intel Open Source Graphics Center