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 D1C52C0015E for ; Mon, 3 Jul 2023 09:32:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229889AbjGCJc2 (ORCPT ); Mon, 3 Jul 2023 05:32:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230377AbjGCJcY (ORCPT ); Mon, 3 Jul 2023 05:32:24 -0400 Received: from mail-ej1-x62e.google.com (mail-ej1-x62e.google.com [IPv6:2a00:1450:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F0B64E5F; Mon, 3 Jul 2023 02:32:14 -0700 (PDT) Received: by mail-ej1-x62e.google.com with SMTP id a640c23a62f3a-99357737980so132666466b.2; Mon, 03 Jul 2023 02:32:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1688376733; x=1690968733; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=nvMYtyGoPKg6lXYME5kTaweQWa3SmJSNHqMo+u8KFsU=; b=dIkHXlNBrl4QT1Wq6cGx2O//dXR7xrTSUmMrvX72UYDHrGSXH+hGFGyzM12EV538BJ MmIE+ct0EyhP7rgDy3/GYe4Js4gZS7OIr41Xx/uW+Pdfx77qJe69vtLFJh8Yd9PbZiFC 2Khse9xxeDcRj3nkPidkIoXgPqgO+z+TO93jY9E/1A3pTuoBEyEV8+pJoVSgtBGi9182 WMrpsRtfhBkFV3tlpKXwCcM66Fy7Ol0j7ilCZwvRwDsTZia+kqDzs3jtvQyLn4GPXE7h qTn6vk0s0RErUej4Lax0zL1OBfwZRy6BpDKa8CXE/F9L0wg1JIm/cMekD+l49Pv53bms 6byQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688376733; x=1690968733; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=nvMYtyGoPKg6lXYME5kTaweQWa3SmJSNHqMo+u8KFsU=; b=bEbCex0vb+p4Qr/c50LCdfqsy5DjhvIzAFuZIt8+IAOXYbdAYnty6GUybNTlEIHHKG 3VNs6WgBLwzYH5QanSSH3dpdE74fLnDm/PlPzVlVkRZo76RetdEYcN3kQAk8c+wPdhF5 x9i9g5s2wSsTbrtZ7sCv5NhPXGRbwiQ6acP8/kEjbV0eAIYyIeWLeqftdCC1zzr4SXa+ Z2forRxYSn/bNSND6Zot75ZO80nVI0YLJja3wIotX+fVC1tdgaowSllVfh+a+Xq9Jz5Z Jhym6dPFyIqhufv5Lw8dx5qYBp5CHoFL0q7LplyvQe5UeahMuyfub3t2R+wpXqEUQSoZ IlxA== X-Gm-Message-State: AC+VfDzuYRKUyGnJolP3JYCPNAceetl1beso2Jo1/1Lz8gJb9fBwk/V2 GKQOLs15r6Mw+hQepBWTBHY= X-Google-Smtp-Source: APBJJlEcBKQ92RfoGW7SIFH16Jl0HjbFTc0Yq5AAdkQl1oFPhntKF1P0GT311c3u4jAVA5XnVGeSYw== X-Received: by 2002:a17:907:766c:b0:982:ab8d:1e08 with SMTP id kk12-20020a170907766c00b00982ab8d1e08mr7027164ejc.59.1688376732881; Mon, 03 Jul 2023 02:32:12 -0700 (PDT) Received: from [192.168.0.131] ([194.183.54.57]) by smtp.gmail.com with ESMTPSA id v26-20020a170906859a00b0099304c10fd3sm3709091ejx.196.2023.07.03.02.32.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 03 Jul 2023 02:32:12 -0700 (PDT) Message-ID: <0d2dcb62-8475-8b2a-7ba9-bdabab3d0aa4@gmail.com> Date: Mon, 3 Jul 2023 11:32:10 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH v2 1/2] led: led-class: Read max-brightness from devicetree To: Astrid Rost , Astrid Rost , Andy Shevchenko , Krzysztof Kozlowski , Rob Herring , Pavel Machek , Lee Jones Cc: kernel@axis.com, linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230630092248.4146169-1-astrid.rost@axis.com> <20230630092248.4146169-2-astrid.rost@axis.com> <3e8e7834-fe0e-7e92-5472-cb9fd223980e@gmail.com> Content-Language: en-US From: Jacek Anaszewski In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Astrid, On 7/3/23 09:53, Astrid Rost wrote: > Hello Jacek, > > I am having problems with the PWM controller LP5024. > > https://www.ti.com/product/LP5024 > > There is no such a calculation in the data-sheet like: > max_brightness = max_current / constant. > > I also assume it is depending on the type of LEDs and circuit, which are > connected. > > It supports two current modes: 25,5 mA and and 35 mA, both is to high > for the LEDs I have. > > For max_brightness seems to be everything inside the kernel, but reading > the value from devicetree. I first thought I could add it in the lp50xx > driver, but Andy and Rob thought that I better put it into the general > parts. And of course drivers having led-max-microamp should better use it. > > Please, let me know if you have a better suggestion. OK, since this LED controller is PWM-driven then there is no current per brightness level granulation. Bindings of leds-pwm driver also use max-brightness DT property. So, yeah, let's make it a common property, but state clearly that it is mainly for drivers like PWM ones, where it is not possible to map brightness level to the amount of current. -- Best regards, Jacek Anaszewski