From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-0301.mail-europe.com (mail-0301.mail-europe.com [188.165.51.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F6691EB5CE for ; Tue, 29 Apr 2025 14:12:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=188.165.51.139 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745935927; cv=none; b=sDMsHhKKO4pvpoZYN6p75RmvP5gYbkPEE1OlU8B1U6gQZCjavX0KHtZdPaR571nGgyBXqZibIZbiQWVU+TZhoeaKMj3tmbThkDWU2QPVxEBORn0iOJWvwCVQnbXIjbMbQfWWIlMjueP5t2/oicsvttB6lcj4a6l/Rjf9CxLG+e8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745935927; c=relaxed/simple; bh=EedXxP4H/gP9dZwClr0nJhcaeU3loAc85FlGQSOdHXo=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=q0klv1DRPOVmy01MqZyWdK0VJ+HomKaji/OukKt/jLFjRcBBH5QgrECoqWbWjfG5oaZe7MiRKoRBhOfav6uEwfoblDsQ3QfumREB/jLa7sHZNqm8lJbIIjZDu0ZbhkLYtLHao/AkjBA63yaIiwtjckqqYLPc8grcnmPNf+8xLvY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=geanix.com; spf=pass smtp.mailfrom=geanix.com; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b=C8sz6Hri; arc=none smtp.client-ip=188.165.51.139 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=geanix.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=geanix.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=geanix.com header.i=@geanix.com header.b="C8sz6Hri" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=geanix.com; s=protonmail; t=1745935911; x=1746195111; bh=EedXxP4H/gP9dZwClr0nJhcaeU3loAc85FlGQSOdHXo=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID:From:To: Cc:Date:Subject:Reply-To:Feedback-ID:Message-ID:BIMI-Selector: List-Unsubscribe:List-Unsubscribe-Post; b=C8sz6Hri6mhi7xT+Mx/PB/QQLCwvYIlcemsD0Dpvu366TnBRw6uQ8jtJBvMv0J9ZI LDcxJldaQyPWeEhWwDOFqZe20NYDkgUAbj2o3xSiLf1IgQ6rHbwt/NoNN+S9Wqy3S5 t9wtOQWsHQkW4QV/sdyCdaIBrqMCWdfvix3mZNzYxYkf5qiwdnnJ3PGR911jgqXaSu T+ElYKfDScUICac9Xp5vS8fXp4qmCQ8xIx5bd1FrGRaHwnCjDTTrDjBDZgAOTgodfC 7EaEMLHsrEgHstlpM2kUu3PlCHJOuUgwXUREyQ/UfXVfFp6m6QhZoIHF2JMUeaazNV psbjOxvbkQNqw== X-Pm-Submission-Id: 4Zn2LY4yQxz4wx0L From: Esben Haabendal To: "Dmitry Torokhov" Cc: "Krzysztof Kozlowski" , "Rob Herring" , "Krzysztof Kozlowski" , "Conor Dooley" , "Hans de Goede" , , , Subject: Re: [PATCH 1/2] dt-bindings: input: touchscreen: goodix: Add no-reset-pull-up property In-Reply-To: <23onpttl3w2wo3625c7flbljahojipsb4xznrx6xynr7rrzofr@2bcvjji7dpu6> (Dmitry Torokhov's message of "Mon, 28 Apr 2025 12:30:47 -0700") References: <20250422-goodix-no-reset-pull-up-v1-0-3983bb65a1bf@geanix.com> <20250422-goodix-no-reset-pull-up-v1-1-3983bb65a1bf@geanix.com> <20250428-logical-successful-spoonbill-cd1c6b@kuoka> <23onpttl3w2wo3625c7flbljahojipsb4xznrx6xynr7rrzofr@2bcvjji7dpu6> Date: Tue, 29 Apr 2025 16:11:48 +0200 Message-ID: <87wmb3t5uj.fsf@geanix.com> User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain "Dmitry Torokhov" writes: > On Mon, Apr 28, 2025 at 07:58:55AM +0000, Esben Haabendal wrote: >> On Monday, April 28th, 2025 at 09:48, Krzysztof Kozlowski wrote: >> > On Tue, Apr 22, 2025 at 05:15:02PM GMT, Esben Haabendal wrote: >> > >> > > This should be added for boards where there is no pull-up on the reset pin, >> > > as the driver will otherwise switch the reset signal to high-impedance to >> > > save power, which obviously not safe without pull-up. >> > > >> > > Signed-off-by: Esben Haabendal esben@geanix.com >> > > --- >> > > Documentation/devicetree/bindings/input/touchscreen/goodix.yaml | 4 ++++ >> > > 1 file changed, 4 insertions(+) >> > > >> > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml >> > > index eb4992f708b70fef93bd4b59b9565123f7c6ad5d..7e5c4b98f2cb1ef61798252ea5c573068a46d4aa 100644 >> > > --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml >> > > +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.yaml >> > > @@ -45,6 +45,10 @@ properties: >> > > reset-gpios: >> > > maxItems: 1 >> > > >> > > + no-reset-pull-up: >> > >> > Is this common property? Where is it defined? Otherwise missing vendor >> > prefix. >> >> Good question. When is something a common property? >> >> The idea of marking something as not having a pull-up on the reset pin could be considered a common thing I guess. >> But for now, I am defining it for the goodix driver only, as I am only aware of these devices needing to handle it in a special way. >> >> Should I rename it to goodix,no-reset-pull-up? > > We already have GPIO_PULL_UP/GPIO_PULL_DOWN flags available in GPIO > bindings. So maybe the correct way is to have the driver rely on them > and only leave the reset line in high-impedance mode if GPIO tells it > that there is a pull-up? As I understand GPIO_PULL_UP/GPIO_PULL_DOWN flags in bindings, they indicate that pull-up/pull-down is to be configured for the gpio. This is different to what I am expressing with goodix,no-reset-pull-up, as I am expressing the lack of external pull-up on the signal. Without that, the goodix driver assumes that an external pull-up is mounted, and that the gpio pin can be set to high impedance, and the external pull-up will ensure that it stays high. How do you propose that we can use GPIO_PULL_UP/GPIO_PULL_DOWN flags for this purpose? /Esben