From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f180.google.com (mail-pf1-f180.google.com [209.85.210.180]) (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 2975833CEB7 for ; Fri, 23 Jan 2026 11:11:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769166666; cv=none; b=IwVSQ9bJh/sVLHCDyOn4QhllgdVCbTQoitww77RZj+FTABbLUwG/6iZMRAfUD2g10cYrFkx5dOUmRSOqmuVSqYoGTk/Y7O+bo22BzUMxzBq5MzY6XVlmu7vvbn5fuECIxShnljYFKkB1fVMI0aj/0qroMBSnUhAkJxdxY9bCYt4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769166666; c=relaxed/simple; bh=JzYSUCqqeWKfNi9rdKkxtfHev0ia4H+r1I/ZRyvcQiI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hkhbp2Hbzu5DNb+dJh3SBz3PkCP6+Ii+Na6oRYoJbh2owZEv4LkdsIBC/asY2b0s8G0nXrOHSmPi8uQ0vKFGeVEkEUxJ1Pm7recEj8rCJV4Rg5nL/YE82Bfct8mV7hmwApBenQ13DqpReaYIjiQwL1UW30SbV23CsYr06jemSU4= 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=hAztp8++; arc=none smtp.client-ip=209.85.210.180 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="hAztp8++" Received: by mail-pf1-f180.google.com with SMTP id d2e1a72fcca58-81f4ba336b4so2276129b3a.1 for ; Fri, 23 Jan 2026 03:11:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1769166663; x=1769771463; 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=54G7XuhdW75vYSZtlnacHikNaLX+O6Mlc4zbY7Y1Luc=; b=hAztp8++AFV3mA0CV5I1xTB6mzXvh0DiZUWpiGqlZOGQvdZZU6qJEc7HprCfpRlM/O P1JP9mpEjogKrEvETqxYGVSrNlQuZ/Y4JoyIzB01x2lKKAM6EBsZ6XlDO0HVxdRB3nr8 ZX85jqkVDgRrfpgLzVYTRIIzs9SmAPoMlY9xf63JUuwC9Krnf02EpO5afVvN6OnVxalw 8rswvL+F9X5RlzfAdLS3vwI68mxSyzKa3XPBWEvDAPrPgkNHWl0qHY0CylpeFP5m1pNa WTSmLmYeFrzOVKYtYgxr5LOC/Pmm399ueF6NFPOLb7ESMCotPxiSuaUh2S4gxmtKCZui HHsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1769166663; x=1769771463; 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=54G7XuhdW75vYSZtlnacHikNaLX+O6Mlc4zbY7Y1Luc=; b=J5Nit86Xu6zxrwNCPUDWjkVO1qEIX/J9tS3C0EkdbcvLSiAJaimFFRBAXJE649ZxJ8 IokCwpymC/VXFi/F4HddYWdk+ycTjwJv2e7Y45vJqYCZRVVTKMK3O6vxu1Dh/Ky8knbe 5o9PUdld46sUTfFQkRrmU87sTjlsUxndpuGFGWN6ivANWVnasih0Tpek6trSJ7RDbpTh w4SCfnye0beJ3u3t4bCX6QU4/9LcpVi37s+fXcet2bSvR/sKCLY1mcJTIlEW1RMpb/Ac N8izB8/5Gy/Fwi4i8aY46iY4MDT4vyWh5VOpv97fZRtOgvNtkFDh+af8gzSd//0kqKaA A6ew== X-Forwarded-Encrypted: i=1; AJvYcCVA2H3PS6p0kIxhQ+04KrfmDLhdJutPMAMwZXn/W2csargiEKuIoBJUbnhk2EQGMPKKaVPHOXe/ZN0I@vger.kernel.org X-Gm-Message-State: AOJu0YxO5ywiW2g7IVASydyQlK2oJ6HCtXn8jqfudzqPFzBGiQJOmQ0K dEzjerrgGv62ddF/J05v0YoawOMcMxZQAPPZK1NnqIWdPRZhRUArTIDP X-Gm-Gg: AZuq6aLsWW9/f9aRaOj4e4Dh+8vso769GlCfIVoKny/JB8k3fGos8xFCZDhuF8QmgVy egY112+jLUvYBOeAQzayjoqcEvo2xGNsM4a9S4wYnJBl/AItSVJJSqZWZO4D0q+YIU8UDQlYgQT 66aaAZ3w7AEQHaaJoUIxZ1hpfeZ2g4+x4Q5mROWx2V5yi05qvdkB1Qsx3Mvwzb7Earh/72s+YBQ IdAsDS8zXo4+8q6sSfiDNvIpmB/34jtvCZA2MtqRN2WfnKDcm4rtOtRP3nTA2jPMEjn+oMaD5hd qkUhWEQOVStgbKavBBTXbRujvgET3iyuMw76FK6K1Q/HWadEIWsotPytfUmYSuYt/74b4g7c539 0c2VBhcFPZ3zQ4Yc5LSDRuMe+2ZwdrWSHxIuXqBTP8Vub2lFZajIgyRP9OQAukh4OQhHW2NUcmH c2F0ytraE5MFgtqSFs8gT+okLWUAeUto62+A== X-Received: by 2002:a05:6a00:bc8c:b0:823:aa5:23f1 with SMTP id d2e1a72fcca58-82317eea693mr2402046b3a.57.1769166663318; Fri, 23 Jan 2026 03:11:03 -0800 (PST) Received: from [172.16.20.12] ([136.226.253.21]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8231864489csm1949221b3a.9.2026.01.23.03.10.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 23 Jan 2026 03:11:02 -0800 (PST) Message-ID: <54d156ba-e177-4059-a808-2505983b4e2e@gmail.com> Date: Fri, 23 Jan 2026 16:41:24 +0530 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] dt-bindings: backlight: gpio-backlight: allow multiple GPIOs To: Krzysztof Kozlowski , lee@kernel.org, danielt@kernel.org, jingoohan1@gmail.com Cc: deller@gmx.de, pavel@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260120125036.2203995-1-tessolveupstream@gmail.com> <20260120125036.2203995-2-tessolveupstream@gmail.com> <3f3c47ea-1660-4bd4-ab89-3bdf58217995@kernel.org> Content-Language: en-US From: tessolveupstream@gmail.com In-Reply-To: <3f3c47ea-1660-4bd4-ab89-3bdf58217995@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 20-01-2026 20:01, Krzysztof Kozlowski wrote: > On 20/01/2026 13:50, Sudarshan Shetty wrote: >> Update the gpio-backlight binding to support configurations that require >> more than one GPIO for enabling/disabling the backlight. > > > Why? Which devices need it? How a backlight would have three enable > GPIOs? I really do not believe, so you need to write proper hardware > justification. > To clarify our hardware setup: the panel requires one GPIO for the backlight enable signal, and it also has a PWM input. Since the QCS615 does not provide a PWM controller for this use case, the PWM input is connected to a GPIO that is driven high to provide a constant 100% duty cycle, as explained in the link below. https://lore.kernel.org/all/20251028061636.724667-1-tessolveupstream@gmail.com/T/#m93ca4e5c7bf055715ed13316d91f0cd544244cf5 >> >> Signed-off-by: Sudarshan Shetty >> --- >> .../leds/backlight/gpio-backlight.yaml | 24 +++++++++++++++++-- >> 1 file changed, 22 insertions(+), 2 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >> index 584030b6b0b9..4e4a856cbcd7 100644 >> --- a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >> +++ b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml >> @@ -16,8 +16,18 @@ properties: >> const: gpio-backlight >> >> gpios: >> - description: The gpio that is used for enabling/disabling the backlight. >> - maxItems: 1 >> + description: | >> + The gpio that is used for enabling/disabling the backlight. >> + Multiple GPIOs can be specified for panels that require several >> + enable signals. All GPIOs are controlled together. >> + type: array > > There is no such syntax in the bindings, from where did you get it? Type > is already defined. > > items: > minItems: 1 > maxItems: 3 > > >> + minItems: 1 >> + items: >> + type: array >> + minItems: 3 >> + maxItems: 3 >> + items: >> + type: integer > > All this is some odd stuff - just to be clear, don't send us LLM output. > I don't want to waste my time to review microslop. > > Was it done with help of Microslop? > I understand now that the schema changes I proposed were not correct, and I will address this in the next patch series. My intention was to check whether the gpio-backlight binding could support more than one enable-type GPIO. Could you please advise what would be an appropriate maximum number of GPIOs for gpio-backlight in such a scenario? For example, would allowing 2 GPIOs be acceptable, or should this case be handled in a different way? > Best regards, > Krzysztof