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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3282AC33C9B for ; Mon, 6 Jan 2020 08:45:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05D1220656 for ; Mon, 6 Jan 2020 08:45:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="b6EoJUPx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726264AbgAFIph (ORCPT ); Mon, 6 Jan 2020 03:45:37 -0500 Received: from mail-wr1-f66.google.com ([209.85.221.66]:38301 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725446AbgAFIph (ORCPT ); Mon, 6 Jan 2020 03:45:37 -0500 Received: by mail-wr1-f66.google.com with SMTP id y17so48744311wrh.5 for ; Mon, 06 Jan 2020 00:45:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=E+ZsR7Z6Or+Q9BNSYlv8m9k1i0fDEt4sNmLSr2qVLrE=; b=b6EoJUPx4omgCfCytDHI5M/8GKVGW1pS/Q0ukuUb7HkffVkKyEWFhHUwnA4PXQB1m5 qAUBj9pMGqUSqG4+z/oaABcxhRaKjqTHoqlJkl1X/pWm++WDEUh6zRHoz2qPVNU28txW kyvLH3wU019LV43vRa1wHHGDYaMIpm0Xt2B1Z2u7WT0FnwzkeDDFea6m2Az5EuZ73VaY iHoRWNHfEGFXf3eWklrzVDg4SX4+I2OI74ZuTK4H7grXGv0dj19Pds60dYhLIqIQme9E zaIZfiYyscy0y1Y3a5N8RLfshXOorElBxVojEvb9ruo0GAXpDWGysJDhxOx6hInEaopG ZPnw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=E+ZsR7Z6Or+Q9BNSYlv8m9k1i0fDEt4sNmLSr2qVLrE=; b=c/mjVZmZjGJnbGUr4kwTK+xky21hZWQhQmrti44YJcFsL3mWByJYFNi15S05bHlSG+ arZu6yqD93n7XpqxHsqNnQaX0DP3M7t6TJ0k7RN+9/QLkgqiFubKvaRHoKLM6S2HsIJF ZLNZCohrEzBIitg22hYAH4mc7jG1HF69MMl1jGIyRdBtPUcZPOb3gCEdfeqZ7ZMf5lVt OHYh8er9z01NeT5pLk7d1ODdC8SW9X5LEeHNR+cThc+x7RZQ0b2XZohjZFQNNLvWfvUX iFkXEc6g8gOspD4VivmiiEF0NiQBMtKARIbz23Vm7RxboOCbwjnz2K/Fs/BYlXMJSX32 8Ndw== X-Gm-Message-State: APjAAAVmdQxGsE0wSohvtYcxeQ2u8Z9fxmCe/wwLnGTV7mhX2MLPFuW7 eprEUTaTiSdh8908WjSpZEuYNw== X-Google-Smtp-Source: APXvYqwxcQQlcWtECdQoOFeMi0PnZaRKIl/UK7OQlM3noxtNGd+dNEVLfF5LUtq5jrb7KMBL2hK+Yg== X-Received: by 2002:a05:6000:118e:: with SMTP id g14mr100885486wrx.39.1578300334744; Mon, 06 Jan 2020 00:45:34 -0800 (PST) Received: from dell ([2.27.35.135]) by smtp.gmail.com with ESMTPSA id q6sm76176240wrx.72.2020.01.06.00.45.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Jan 2020 00:45:34 -0800 (PST) Date: Mon, 6 Jan 2020 08:45:49 +0000 From: Lee Jones To: Pavel Machek Cc: kernel list , linux-arm-kernel , linux-omap@vger.kernel.org, tony@atomide.com, sre@kernel.org, nekit1000@gmail.com, mpartap@gmx.net, merlijn@wizzup.org, martin_rysavy@centrum.cz, agx@sigxcpu.org, daniel.thompson@linaro.org, jingoohan1@gmail.com, dri-devel@lists.freedesktop.org, tomi.valkeinen@ti.com, jjhiblot@ti.com Subject: Re: LED backlight on Droid 4 and others Message-ID: <20200106084549.GA14821@dell> References: <20200105183202.GA17784@duo.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200105183202.GA17784@duo.ucw.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 05 Jan 2020, Pavel Machek wrote: > Hi! > > It would be good to get LED backlight to work in clean way for 5.6 > kernel. > > As far as I can see, these are neccessary (but not enough; it does not > work for me): lm3532 changes to register LED with of node, plus device > tree changes for droid 4, and these generic changes: > > commit d457d0c97d6d55fe3e62633791ac05d289a37d2e > Author: Tomi Valkeinen > Date: Thu Oct 3 10:28:12 2019 +0200 > > backlight: add led-backlight driver > > This patch adds a led-backlight driver (led_bl), which is similar to > pwm_bl except the driver uses a LED class driver to adjust the > brightness in the HW. Multiple LEDs can be used for a single backlight. > > Signed-off-by: Tomi Valkeinen > Signed-off-by: Jean-Jacques Hiblot > Acked-by: Pavel Machek > Reviewed-by: Daniel Thompson > > commit 44b7adbf0b07904e4198ae1d0a763917d1c68a23 > Author: Jean-Jacques Hiblot > Date: Thu Oct 3 10:28:10 2019 +0200 > > leds: Add managed API to get a LED from a device driver > > If the LED is acquired by a consumer device with devm_led_get(), it is > automatically released when the device is detached. > > Signed-off-by: Jean-Jacques Hiblot > Acked-by: Pavel Machek > Signed-off-by: Pavel > > commit 93b98c570d7f898063ab6204e1b3950a3335dd12 > Author: Tomi Valkeinen > Date: Thu Oct 3 10:28:09 2019 +0200 > > leds: Add of_led_get() and led_put() > > This patch adds basic support for a kernel driver to get a LED device. > This will be used by the led-backlight driver. > > Only OF version is implemented for now, and the behavior is similar to > PWM's of_pwm_get() and pwm_put(). > > Signed-off-by: Tomi Valkeinen > Signed-off-by: Jean-Jacques Hiblot > Acked-by: Pavel Machek > Signed-off-by: Pavel > > [If you have an idea what else is needed, it would be welcome; it > works for me in development tree but not in tree I'd like to > upstream.] > > Lee, would you be willing to take "backlight: add led-backlight > driver"? Would it help if I got "leds: Add managed API to get a LED > from a device driver" and "leds: Add of_led_get() and led_put()" into > for_next tree of the LED subsystem? It looks like you have an open question from Tony on v10. Is that patch orthogonal, or are there depend{ants,encies}? > It is kind of important as, well, phone without screen looks pretty > much dead, and same issue hits Droid 4 and Librem 5 phones at least... > > Best regards, > Pavel -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog