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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A49F2C5AD55 for ; Mon, 10 Aug 2026 20:35:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=5fkRRQESuJogTJbUlw1TtnlKX+cyZWiGY0fHfzIT9Xw=; b=p1bC13eKlBb/l+0QmmDo22H7zF scsdcMzicHLIunGwWTTagMWx+GpPLQ8bf6o8gUSPfaNPMjlqtpqBZuMKGBe/xgMSiFaAVJjJcFJjj kJxg2BQz7IXQr3eOLcP504VHVc25kM3GG2Eqp9NL43ZH0/4DJpkl5CLbK+Zmqdrda1PBVi4q8fFx9 pCsG2o/H+hpffx2TDBvFcFl25zAq+wlHG3purIWycUlxe81cPjCwr3JNeRG2zqBF/gmo0aYLf6Zvi zoyQWS+rX/1EYNpKcmckjrkKCvU/LwqPfXFWp18EfLpAM1JG9e+tjjp8WB41pae3GAG0+wvx63Ul5 Y03HI0Cw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wtWhu-0000000CqIH-3pGz; Mon, 10 Aug 2026 20:34:50 +0000 Received: from mail.andi.de1.cc ([2a02:c205:3004:2154::1]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wtWhs-0000000CqHw-3fWx for linux-arm-kernel@lists.infradead.org; Mon, 10 Aug 2026 20:34:50 +0000 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=1786394088; x=1787603688; b=dPldqICuN9PL/26ZE6jDyxPMn0dFNkGDV292XxKH9gQV+MVM+BO7BxVBnyg2BBYEvxsOCiv+st6 GAvjgW8okc3s9sUr3SxJAxf/TH6e61RFNFS818CXfDIFWqM00SZvZhgCTc2OR2grAKgZr3PJ4Yt3t wXlm1onGhvBYFaPdzTds7ITPIl5lbqCCt3JexrvmwB9EJPSrtBPwuNOpp4Pq3djXe05gcV6YRGKkY qEvZNqw+dDHZmPVTw1N+QbgHlTjGuHgVlJimb3HjXKB7MWrLN38FmUFHi6dVoJDcJECFpUeFc3Exs XfLYE6Nni6jRcrQK5kGFex81uAm/CdKkLFrg==; 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) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260810_133448_931230_0D0C7251 X-CRM114-Status: GOOD ( 22.29 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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