From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.gmx.net (mout.gmx.net [212.227.15.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6DA171547F5; Thu, 12 Dec 2024 23:56:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.15.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734047792; cv=none; b=tJgfZ5BDRObOvAnLkn8bAsALlgew6n9jKgHp0jlzunWubjLGID0miN9b7/06wNdZsGJBct09xg+rkEKlXGtAr8tekRl9urvSnGEh5DnMkDSjDxEOGK1gfb0K2xVl6gyCE9sM6SCnxIridV8XqN3OWuTFdHsGcyQJZvVBIcPa4LY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734047792; c=relaxed/simple; bh=Y9YqNVWsDuVzEUXdFg3v61keriM70N/RseVxO3PvFg8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=O52aTGIsUABhThyBnJapoF/REFsgrQmxOVeLMATI4u7hECxv5eQqpiuYqtc8DnZwgwHdpWL7RDJpW/b/soqy/00mLWaB4qHqVq2Lak6LXEX5pfnj7eOMUmYR5Gf3lmZ3nYvzioDBLvaehVtUkrFwcl7aP4F8WqkvZS0Y9s9oyr0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=gmx.de; spf=pass smtp.mailfrom=gmx.de; dkim=pass (2048-bit key) header.d=gmx.de header.i=deller@gmx.de header.b=U35My+cN; arc=none smtp.client-ip=212.227.15.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=gmx.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmx.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmx.de header.i=deller@gmx.de header.b="U35My+cN" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmx.de; s=s31663417; t=1734047775; x=1734652575; i=deller@gmx.de; bh=IPHedqRcXgtemeOKgImVqUQipKbdg4WLkUhhernilOo=; h=X-UI-Sender-Class:Message-ID:Date:MIME-Version:Subject:To:Cc: References:From:In-Reply-To:Content-Type: Content-Transfer-Encoding:cc:content-transfer-encoding: content-type:date:from:message-id:mime-version:reply-to:subject: to; b=U35My+cNcqr3STDj2lNu1MkLkY4Q42PCVEtQOr6vajhIB7sPotFvG53D2BP0EOvz bIVnMTM5EcDsxxarG/LETdHcCiast7HCSBZn8jDt1tMdYyMQGQ5CKiM1nUtgVt/Ct JPIduXFYCC2WykCmdLqSQrWTkt5Aayrgydo+tBqSvKZxGZS5JIgNHJX6XNDARQEvj w2HayzxxPfxBzmJaF/zUKuzG1LG21bMHFb7omwsWSoSp+dbR2kMnHhkh5exvS/rFi FoiOV8uGbLzrBZuJDNuMLCJe75lN/x7eyC6CX3QT54wBeD+4cdMvtmEhMpEGQX7DM cYqVwLziHhYmLINlcQ== X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a Received: from [192.168.20.172] ([109.250.63.155]) by mail.gmx.net (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1MRCOE-1t0uGx3Boa-00SHJ2; Fri, 13 Dec 2024 00:56:15 +0100 Message-ID: <2701e824-d330-49c0-88fa-a26658a9710c@gmx.de> Date: Fri, 13 Dec 2024 00:56:13 +0100 Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/3] fbdev: Fix recursive dependencies wrt BACKLIGHT_CLASS_DEVICE To: Jani Nikula , Arnd Bergmann , Thomas Zimmermann , Javier Martinez Canillas , Simona Vetter , Dave Airlie Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-staging@lists.linux.dev, linuxppc-dev@lists.ozlabs.org References: <20241212100636.45875-1-tzimmermann@suse.de> <20241212100636.45875-2-tzimmermann@suse.de> <09edb59a-527a-4ddb-bfaf-ea74fb5a3023@gmx.de> <88ce6863-4458-47cb-9b28-274c91bd8764@app.fastmail.com> <87frmstrhd.fsf@intel.com> Content-Language: en-US From: Helge Deller Autocrypt: addr=deller@gmx.de; keydata= xsFNBF3Ia3MBEAD3nmWzMgQByYAWnb9cNqspnkb2GLVKzhoH2QD4eRpyDLA/3smlClbeKkWT HLnjgkbPFDmcmCz5V0Wv1mKYRClAHPCIBIJgyICqqUZo2qGmKstUx3pFAiztlXBANpRECgwJ r+8w6mkccOM9GhoPU0vMaD/UVJcJQzvrxVHO8EHS36aUkjKd6cOpdVbCt3qx8cEhCmaFEO6u CL+k5AZQoABbFQEBocZE1/lSYzaHkcHrjn4cQjc3CffXnUVYwlo8EYOtAHgMDC39s9a7S90L 69l6G73lYBD/Br5lnDPlG6dKfGFZZpQ1h8/x+Qz366Ojfq9MuuRJg7ZQpe6foiOtqwKym/zV dVvSdOOc5sHSpfwu5+BVAAyBd6hw4NddlAQUjHSRs3zJ9OfrEx2d3mIfXZ7+pMhZ7qX0Axlq Lq+B5cfLpzkPAgKn11tfXFxP+hcPHIts0bnDz4EEp+HraW+oRCH2m57Y9zhcJTOJaLw4YpTY GRUlF076vZ2Hz/xMEvIJddRGId7UXZgH9a32NDf+BUjWEZvFt1wFSW1r7zb7oGCwZMy2LI/G aHQv/N0NeFMd28z+deyxd0k1CGefHJuJcOJDVtcE1rGQ43aDhWSpXvXKDj42vFD2We6uIo9D 1VNre2+uAxFzqqf026H6cH8hin9Vnx7p3uq3Dka/Y/qmRFnKVQARAQABzRxIZWxnZSBEZWxs ZXIgPGRlbGxlckBnbXguZGU+wsGRBBMBCAA7AhsDBQsJCAcCBhUKCQgLAgQWAgMBAh4BAheA FiEERUSCKCzZENvvPSX4Pl89BKeiRgMFAl3J1zsCGQEACgkQPl89BKeiRgNK7xAAg6kJTPje uBm9PJTUxXaoaLJFXbYdSPfXhqX/BI9Xi2VzhwC2nSmizdFbeobQBTtRIz5LPhjk95t11q0s uP5htzNISPpwxiYZGKrNnXfcPlziI2bUtlz4ke34cLK6MIl1kbS0/kJBxhiXyvyTWk2JmkMi REjR84lCMAoJd1OM9XGFOg94BT5aLlEKFcld9qj7B4UFpma8RbRUpUWdo0omAEgrnhaKJwV8 qt0ULaF/kyP5qbI8iA2PAvIjq73dA4LNKdMFPG7Rw8yITQ1Vi0DlDgDT2RLvKxEQC0o3C6O4 iQq7qamsThLK0JSDRdLDnq6Phv+Yahd7sDMYuk3gIdoyczRkXzncWAYq7XTWl7nZYBVXG1D8 gkdclsnHzEKpTQIzn/rGyZshsjL4pxVUIpw/vdfx8oNRLKj7iduf11g2kFP71e9v2PP94ik3 Xi9oszP+fP770J0B8QM8w745BrcQm41SsILjArK+5mMHrYhM4ZFN7aipK3UXDNs3vjN+t0zi qErzlrxXtsX4J6nqjs/mF9frVkpv7OTAzj7pjFHv0Bu8pRm4AyW6Y5/H6jOup6nkJdP/AFDu 5ImdlA0jhr3iLk9s9WnjBUHyMYu+HD7qR3yhX6uWxg2oB2FWVMRLXbPEt2hRGq09rVQS7DBy dbZgPwou7pD8MTfQhGmDJFKm2jvOwU0EXchrcwEQAOsDQjdtPeaRt8EP2pc8tG+g9eiiX9Sh rX87SLSeKF6uHpEJ3VbhafIU6A7hy7RcIJnQz0hEUdXjH774B8YD3JKnAtfAyuIU2/rOGa/v UN4BY6U6TVIOv9piVQByBthGQh4YHhePSKtPzK9Pv/6rd8H3IWnJK/dXiUDQllkedrENXrZp eLUjhyp94ooo9XqRl44YqlsrSUh+BzW7wqwfmu26UjmAzIZYVCPCq5IjD96QrhLf6naY6En3 ++tqCAWPkqKvWfRdXPOz4GK08uhcBp3jZHTVkcbo5qahVpv8Y8mzOvSIAxnIjb+cklVxjyY9 dVlrhfKiK5L+zA2fWUreVBqLs1SjfHm5OGuQ2qqzVcMYJGH/uisJn22VXB1c48yYyGv2HUN5 lC1JHQUV9734I5cczA2Gfo27nTHy3zANj4hy+s/q1adzvn7hMokU7OehwKrNXafFfwWVK3OG 1dSjWtgIv5KJi1XZk5TV6JlPZSqj4D8pUwIx3KSp0cD7xTEZATRfc47Yc+cyKcXG034tNEAc xZNTR1kMi9njdxc1wzM9T6pspTtA0vuD3ee94Dg+nDrH1As24uwfFLguiILPzpl0kLaPYYgB wumlL2nGcB6RVRRFMiAS5uOTEk+sJ/tRiQwO3K8vmaECaNJRfJC7weH+jww1Dzo0f1TP6rUa fTBRABEBAAHCwXYEGAEIACAWIQRFRIIoLNkQ2+89Jfg+Xz0Ep6JGAwUCXchrcwIbDAAKCRA+ Xz0Ep6JGAxtdEAC54NQMBwjUNqBNCMsh6WrwQwbg9tkJw718QHPw43gKFSxFIYzdBzD/YMPH l+2fFiefvmI4uNDjlyCITGSM+T6b8cA7YAKvZhzJyJSS7pRzsIKGjhk7zADL1+PJei9p9idy RbmFKo0dAL+ac0t/EZULHGPuIiavWLgwYLVoUEBwz86ZtEtVmDmEsj8ryWw75ZIarNDhV74s BdM2ffUJk3+vWe25BPcJiaZkTuFt+xt2CdbvpZv3IPrEkp9GAKof2hHdFCRKMtgxBo8Kao6p Ws/Vv68FusAi94ySuZT3fp1xGWWf5+1jX4ylC//w0Rj85QihTpA2MylORUNFvH0MRJx4mlFk XN6G+5jIIJhG46LUucQ28+VyEDNcGL3tarnkw8ngEhAbnvMJ2RTx8vGh7PssKaGzAUmNNZiG MB4mPKqvDZ02j1wp7vthQcOEg08z1+XHXb8ZZKST7yTVa5P89JymGE8CBGdQaAXnqYK3/yWf FwRDcGV6nxanxZGKEkSHHOm8jHwvQWvPP73pvuPBEPtKGLzbgd7OOcGZWtq2hNC6cRtsRdDx 4TAGMCz4j238m+2mdbdhRh3iBnWT5yPFfnv/2IjFAk+sdix1Mrr+LIDF++kiekeq0yUpDdc4 ExBy2xf6dd+tuFFBp3/VDN4U0UfG4QJ2fg19zE5Z8dS4jGIbLg== In-Reply-To: <87frmstrhd.fsf@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:f/tY40eYye9ZgQ21QIZ3UfoGC9TYQj96ENEo121+bOqKcMN70ul +joHPzY3qrEnAcraBFbamjoktxyKHGPQLDroMFrpxKLHxgiiVUXZMDwUzWj31mXLbWDv3Rd Ne4rn8ZuOuiiAqHbV5yW9VCRRwYmpL/Inke/z7QBiTopaAo+IZRK9XcXZC6+OcYZ0W/MGXS D564DlnYp08esiNT3NCyQ== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:Vva+NIhCaCU=;0WtonTJcKg+Sh1IVGvOkSKjma3E q0BqJCz9w5o/bzKVx91i/qtZSAQvDzKppLUmhTGvj0y7KMEuuR7rG+88QyCkryX77O/HWtCI3 DMIM3JhXR3GffmgbvT0h5fER/6uqdhmAAy5HTpg0tu7WK9j6e0XN0WZ5kWhY2YAW7WpfByngZ y8Bts5H5aysQ3tzK0IAM+0K8ZSwnklXyb6VENIFkn3HXENCRooYcwwmncicV4e7nXXLHEUMg/ BHu289LpBJlXDNNNyVDkM5hW7cAbRJU0yI7bL403t/kHmgFGklJFhs+ueeckWRc+kCMmaqZZN aMWoFHwd2Bp8mMdUwojuZ455JhqFZUERp7cszL98gfELf01eona0jdNRbmqIsRNHbbJ/z5QLP Ts7VvNOlxWF0nd+mwXK0OQ8Bk0JmKpqRfjmA3FrpwEKYFT6w2FTQ173U8RZVIgpJQ++qpHvaS nAJG32PzKtzFtIACDs2Bfc9EOrkNy4nwwvYaBuDttS1vAsnUwkrL8vgn5UD7OHIGy9e58R2L6 3utFZoN6Jdf9R0UKYnzF1oJNtYCrY9Y//RoDh+1ZG3DTLPi1aFJ7dVO2PfDivqAVtwQ62EbCP debymYBVwnVruTI5MNaKRa8jrhDD2UTfJ6XPSvHLjHPVptr6QcqlvK40n7QrvUdpR2o17dLzz Vkai1y9zMm16eadd7YPhL1wCWyD6F9eWuc9vTJxd4sLge1XkFP1VQqsyrNTDh7z7kIBD8IKj5 nwh6zExxFq/VVyVUqPadhRmYQ54SdemtcJ+qMq7O2Zw937eXhvEbNvHV7zDAaE6jnYQ7mVqlO KJl2TmoVM26L1EfszwJdIpsqDx6SHZNg9obKWQ9kLDsp7W1ZF4NWRWl7y/3rqQh0cD9jeUn2h rbDHRj+390zF3l0HSY7yrviN/0AD4sXw3WJXXnrVrAk9B/vgv6A3mf3mpaowIsV0XVVs7F0yg 3SI8otev+7Fb6x9h/aHoYvcvV84IJX1FnRxbvjDtzYtTDkuch6N98IJ+oXe+FofM247HinDG9 5Qj7nhhZ7zaz6jJL4q3NhHRErG2hEW0VVA9u31Q+0d/0uuXw8bKOERYhY9xISIgwUcL6UZe9f uu+WHSq9sDPXKRdD+uN4O9zjz/5Iu/ On 12/13/24 00:24, Jani Nikula wrote: > On Thu, 12 Dec 2024, "Arnd Bergmann" wrote: >> On Thu, Dec 12, 2024, at 19:44, Helge Deller wrote: >>> On 12/12/24 11:04, Thomas Zimmermann wrote: >>>> Do not select BACKLIGHT_CLASS_DEVICE from FB_BACKLIGHT. The latter >>>> only controls backlight support within fbdev core code and data >>>> structures. >>>> >>>> Make fbdev drivers depend on BACKLIGHT_CLASS_DEVICE and let users >>>> select it explicitly. Fixes warnings about recursive dependencies, >>>> such as [...] >>> >>> I think in the fbdev drivers themselves you should do: >>> select BACKLIGHT_CLASS_DEVICE >>> instead of "depending" on it. >>> This is the way as it's done in the DRM tiny and the i915/gma500 DRM d= rivers. >>> >>> So, something like: >>> >>> --- a/drivers/staging/fbtft/Kconfig >>> tristate "Support for small TFT LCD display modules" >>> depends on FB && SPI >>> depends on FB_DEVICE >>> + select BACKLIGHT_DEVICE_CLASS >>> depends on GPIOLIB || COMPILE_TEST >>> select FB_BACKLIGHT >>> >>> config FB_BACKLIGHT >>> tristate >>> depends on FB >>> - select BACKLIGHT_CLASS_DEVICE >>> + depends on BACKLIGHT_CLASS_DEVICE >>> >>> >>> Would that fix the dependency warning? >> >> The above is generally a mistake and the root cause of the >> dependency loops. With very few exceptions, the solution in >> these cases is to find the inconsistent 'select' and change >> it into 'depends on'. > > Agreed. That's fine, but my point is that it should be consistent. For example: ~:/git-kernel/linux$ grep -r "select.*BACKLIGHT_CLASS_DEVICE" drivers/gpu/ drivers/gpu/drm/tilcdc/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/nouveau/Kconfig: select BACKLIGHT_CLASS_DEVICE if D= RM_NOUVEAU_BACKLIGHT drivers/gpu/drm/nouveau/Kconfig: select BACKLIGHT_CLASS_DEVICE if A= CPI && X86 drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/tiny/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/fsl-dcu/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/i915/Kconfig: select BACKLIGHT_CLASS_DEVICE if ACPI drivers/gpu/drm/gma500/Kconfig: select BACKLIGHT_CLASS_DEVICE if ACPI drivers/gpu/drm/amd/amdgpu/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/xe/Kconfig: select BACKLIGHT_CLASS_DEVICE if ACPI drivers/gpu/drm/solomon/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/radeon/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/renesas/shmobile/Kconfig: select BACKLIGHT_CLASS_DEV= ICE drivers/gpu/drm/gud/Kconfig: select BACKLIGHT_CLASS_DEVICE drivers/gpu/drm/bridge/Kconfig: select BACKLIGHT_CLASS_DEVICE All major drm graphics drivers *select* BACKLIGHT_CLASS_DEVICE. Are you changing them to "depend on" as well? Helge