From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f42.google.com (mail-wr1-f42.google.com [209.85.221.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 57BB3363C49 for ; Wed, 25 Mar 2026 20:41:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774471298; cv=none; b=jVG4Ci0VCyCEPqLRFJXCdbtjftOs7Nxy0OX+ctKtklBASw+LUM2dCwknyWfmOvvm3bJBRqZKflZ8/bMi1JAcREpubC50CRRXCZZSwuzSscdO/CbW6P5tebK9tYR/1D/N9jXUuXa3FOD+rKQIS8qaYgO7/pn4cGrNxYva/Mh15go= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774471298; c=relaxed/simple; bh=VVqlxxHZRb8tZz7boU+dlmsJ/0Syk+ZaUNbpJjU3WX0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=VkCzpnWpD5MXOs6mgad+8hTaPS5FPLqmSNJkvOIEY73ixqZ98f03IrVBaLHffwfd1W7r4CyEVkcl9zV9IO0vd/4HZ4e8DpZKpH6mOtK2Mgvad4QdUM/fPrnUNjEYaSfbQ+EUjg1VPtVBtlRzqKmI0w+vgR4CREpl9tmt3eLYmnk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=U724P3T4; arc=none smtp.client-ip=209.85.221.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="U724P3T4" Received: by mail-wr1-f42.google.com with SMTP id ffacd0b85a97d-439bcec8613so156117f8f.3 for ; Wed, 25 Mar 2026 13:41:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1774471295; x=1775076095; darn=vger.kernel.org; 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=z+jLlAQMFJeoih+XE7tLpkictTKxnhNTWJHKi8OqzAA=; b=U724P3T45RJC2d4Z1hSbP7gJa4CMMNTbuJlajn5tzNW+q9fmQjE1KOSltxCcUI5sBc fSmYYA2k86eqz7hOEXQtu/EbcqsoIvxTdOa3AxM2rA+CDooE1XsgFZcPxjPoDBPS3Sz9 dFpC85PTSPDwi2LUtzknujzPIXfolL+rT0zb24rUgyGovRUOoI+twQsTWOj/sr7aQE+f O1f0AgXqYkj/EppHosIO6t80e+BHB8AviL0qTSS9E8H6cvAm0OAlVMdhby/Dqr1sk/yh mUIIhVfk434FKUE2pKltoPEebTt05zhvf9/uWurTNXk+oK5Rjpf+zIBjR8+JQaoAgoLl rFeQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774471295; x=1775076095; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=z+jLlAQMFJeoih+XE7tLpkictTKxnhNTWJHKi8OqzAA=; b=O0OBA9ujQjnRt6w7SgJaMvTikj2RwQrCnaY6yjO1vw25HoMHTfIKwmBAwMVAjQeTmQ fPHC7I8RNvqPlhUOl5zI+TO2VqJgwgDwilzDJ+Hq2nX4Q7N00ggXdQg8TktbOqxNk129 bgsWnt/QhuhHt64LTGORvxLc/EXx6VzrRwUrd+LAhWmLlKOlSgRoezK5KDgY7xr9s9jn xuQqbqIroW2fE9aXeGLJLo03/wzHRkrJ3vh4F7A48aQUyRlvvpgkSlxg6R4DGQodW9Y1 p2Yme2g61nwIexcMJfXnOaLXXYdJwdoWPOmPihGxESEVYdTe6Sy+YO7g3Kr1wFe88DyL vCfQ== X-Forwarded-Encrypted: i=1; AJvYcCUcAmbBY+qPPRg0PEwu/I93Ys5uSmOIRC5OJM/YiAXNqRpFwNIxe6ah0678b3Ev4JgjiSvD6Qnv5IA=@vger.kernel.org X-Gm-Message-State: AOJu0YwKfhxkPVfgo4rBAkCGnU0tYC71dzlgy/ZtvjqBUrV4kJLI2PCD 9vwcyL2H9Zegix1MDnEa6zBpM9TmFqP4kyuJtTAKjoE3QOIxfRIdkXap X-Gm-Gg: ATEYQzxYgGuJ5BfvZz7sXmJHwIp5utKtE8dV3vtFk8QdKpjsGryevApZiYUezeaKHss lvIVn8cX68nTaThTR37egaAyAa5MX4xEiwF65xo+D+p8501nn39eebks0HpBHlPGfHxkdbIXNy8 LW31alS/psPu5vkjWfZHmNRPBnardpx/SQDKZKfjv71Ag7lI9OcawpSqzh3MmWRQHqRKRCj6oyN wFp0GHq07Ft2QPTE+/Zwy04e/paKrLGpJqaDvfa4pp6eUlVsQw2r5epsRyortR0RGwZLnuxjZ8D IY5QEajkXKBHdkej5z3h16hK/6nk+3FdKyqzaI7N8LR6T9J6EJMGGmnFxPMh3kgZ0EEiUxalONO TyaFjcnFr3rxk7f+f9IUUmVMx6OIBAmku0sH+7/KPUIZiCyx6qHcC8SE5e7InBcBZint64eBNFg 2mAHV3Fyj+FkQ+IVQX9wRuHw10D+PAXkl/z1lpkltVzdceuw== X-Received: by 2002:a05:600c:35c6:b0:486:fb69:4960 with SMTP id 5b1f17b1804b1-4871603508fmr80589005e9.19.1774471295365; Wed, 25 Mar 2026 13:41:35 -0700 (PDT) Received: from [192.168.0.193] ([194.183.54.57]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4871fb3fc8esm6706615e9.11.2026.03.25.13.41.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 25 Mar 2026 13:41:34 -0700 (PDT) Message-ID: Date: Wed, 25 Mar 2026 21:41:33 +0100 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/1] leds: Introduce the multi_max_intensity sysfs attribute To: Armin Wolf , lee@kernel.org, pavel@kernel.org Cc: linux-kernel@vger.kernel.org, corbet@lwn.net, skhan@linuxfoundation.org, linux-leds@vger.kernel.org, linux-doc@vger.kernel.org, wse@tuxedocomputers.com, pobrn@protonmail.com, m.tretter@pengutronix.de References: <20260324202751.6486-1-W_Armin@gmx.de> <20260324202751.6486-2-W_Armin@gmx.de> Content-Language: en-US From: Jacek Anaszewski In-Reply-To: <20260324202751.6486-2-W_Armin@gmx.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Armin, Thanks for the update. On 3/24/26 9:27 PM, Armin Wolf wrote: > Some multicolor LEDs support global brightness control in hardware, > meaning that the maximum intensity of the color components is not > connected to the maximum global brightness. Such LEDs cannot be > described properly by the current multicolor LED class interface, > because it assumes that the maximum intensity of each color component > is described by the maximum global brightness of the LED. > > Fix this by introducing a new sysfs attribute called > "multi_max_intensity" holding the maximum intensity values for the > color components of a multicolor LED class device. Drivers can use > the new max_intensity field inside struct mc_subled to tell the > multicolor LED class code about those values. Intensity values written > by userspace applications will be limited to this maximum value. > > Drivers for multicolor LEDs that do not support global brightness > control in hardware might still want to use the maximum global LED > brightness supplied via devicetree as the maximum intensity of each > individual color component. Such drivers should set max_intensity > to 0 so that the multicolor LED core can act accordingly. > > The lp50xx and ncp5623 LED drivers already use hardware-based control > for the global LED brightness. Modify those drivers to correctly > initalize .max_intensity to avoid being limited to the maximum global > brightness supplied via devicetree. > > Signed-off-by: Armin Wolf > --- > .../ABI/testing/sysfs-class-led-multicolor | 19 ++++++-- > Documentation/leds/leds-class-multicolor.rst | 21 ++++++++- > drivers/leds/led-class-multicolor.c | 47 ++++++++++++++++++- > drivers/leds/leds-lp50xx.c | 1 + > drivers/leds/rgb/leds-ncp5623.c | 4 +- > include/linux/led-class-multicolor.h | 30 +++++++++++- > 6 files changed, 113 insertions(+), 9 deletions(-) Reviewed-by: Jacek Anaszewski -- Best regards, Jacek Anaszewski