From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.andi.de1.cc (mail.andi.de1.cc [178.238.236.174]) (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 EAB912236F0; Mon, 10 Aug 2026 20:34:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.238.236.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786394092; cv=none; b=JyQiZkpyVVNKqEH0m5nDMkNeweLG9gSrOb9AeBPdonlf1FiFyCP+bcsHu1FlKAd8Kc/giwOssMkQ78Na1wfsK7kx1xBB3Gezhd0EQbQUU7VaXDxo7AMv1p6Lg9k6Ea2LtImKOUW15q+Ig2D4+8cU6MdQWzqfsSdGNYvvg5BBaFk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786394092; c=relaxed/simple; bh=Z//gjbzolO0j9Ht17OZ+pUqamuxMGAP6Onswa//Ty8s=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=RJ71kTOT+OH80WEwCIQBpXJQdGU4zaFWvNMSbEKq3QYATUrWxzFl7jAHdJxEOeqv0LSY6tNRZY4Zv+WxY1wcHBoF02VuKFyjEROAKBI/riRISBAcg6tMhnFqbYssoy0x7W+PKaV77vZ+/z+s9FxMgjMjNEpoD4cxmzhHpKxg4bw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kemnade.info; spf=pass smtp.mailfrom=kemnade.info; dkim=pass (2048-bit key) header.d=kemnade.info header.i=@kemnade.info header.b=x+SM9lp3; arc=none smtp.client-ip=178.238.236.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kemnade.info Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kemnade.info Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kemnade.info header.i=@kemnade.info header.b="x+SM9lp3" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kemnade.info; s=20220719; h=References:In-Reply-To:Subject:Cc:To:From: Reply-To:Content-ID:Content-Description; bh=5fkRRQESuJogTJbUlw1TtnlKX+cyZWiGY0fHfzIT9Xw=; t=1786394091; x=1787603691; b=x+SM9lp3qedBZNa0ryQpDezSB/inEjpK6a0Ncv/aDg+46a+sIPpCYREV6svIx9DresYp2cn8DaP DnYI8JakFbLqPBzglrKDV5esJvGhrvoVjgjZwSi2lga5D+cW/+sMCNQc6Z6E2G9qARusJxT3T2a/F +uBmivzCBzew11xJ/6x3uVZN4czq7pBtNoWrTfgVLN1xsRISFuxNoiBmltCF227p0PsO29j7dLRQy 0Hun4HhKYWtFMt8LIUnYW/UJNYcDbZc0w7URtHknOnxJmprh5zuJIjI6kpdEeodjA+3PzQiYns2nC PycP+ZbDhi1YBQhsEaIKpRJsvT/QjAjNDhlA==; Date: Mon, 10 Aug 2026 22:34:13 +0200 From: Andreas Kemnade To: "H. Nikolaus Schaller" Cc: Daniel Thompson , Grond , Stefan Leichter , Grazvydas Ignotas , Tony Lindgren , Ethan Nelson-Moore , Jarkko Nikula , Sascha Hauer , Lee Jones , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Liam Girdwood , Mark Brown , Aaro Koskinen , Kevin Hilman , Roger Quadros , Russell King , Jingoo Han , Helge Deller , Jaroslav Kysela , Takashi Iwai , Sen Wang , Richard Fitzgerald , Arnd Bergmann , Srinivas Kandagatla , Kuninori Morimoto , Charles Keepax , Niranjan H Y , letux-kernel@openphoenux.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, kernel@pyra-handheld.com, mfd@lists.linux.dev Subject: Re: [PATCH 15/16] backlight: remove pandora_bl Message-ID: <20260810223413.01af9a6d@kemnade.info> In-Reply-To: <92FE1162-8C61-4186-B073-6AB4B2BDA640@goldelico.com> References: <20260810143914.64d29a5c@kemnade.info> <2C9844A3-3C4C-48E6-863D-BF8328CEE540@goldelico.com> <92FE1162-8C61-4186-B073-6AB4B2BDA640@goldelico.com> X-Mailer: Claws Mail 4.3.1 (GTK 3.24.49; aarch64-unknown-linux-gnu) Precedence: bulk X-Mailing-List: linux-fbdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 10 Aug 2026 20:30:13 +0200 "H. Nikolaus Schaller" wrote: > > > > Yes that is what I mean. It needs to be ported somewhere. If it can be ported to > > some compatible = "pwm_bl_for_tps61161" or what fits best it will be fine. Or it > > could be in some compatible = "pandora_bl" driver. > > > > Has to be worked out when the development machines are not blocked by 3 or 4 other > > projects already running in parallel :) > > Nevertheless I did a quick look into the pandora_bl driver structure. > > Here are my findings: > - the code fragment is part of pandora_backlight_update_status() > - priv->old_state remembers if brighness was set to 0 or not > - so this code triggers on any change from bright = 0 to bright > 0 > - the pandora_bl driver is the only one to use TWL_MODULE_PWM besides twl-pwm > > So the most natural way of transplanting this appears to me: > - add this logic to the twl-pwm driver That chip could be connected to any pwm driver, so it does not make sense to have that in a pwm driver. So it belongs into a backlight driver. And since it shared so much code with the pwm_bl, it could be extended. The compatible should have pwm in the name to be able to also add a w1 driver later. Regards, Andreas