From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1702B2D04F; Sun, 28 Jan 2024 17:38:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706463538; cv=none; b=PE585S+hFzjpS3i5MdJV62L5Bq2hUUgh4SCfR4OfYRkhou4IM123ZWWpVfcBHvlGOyLByUjpVS9mjTA1KEiJCCIkDcPqEM2KVejl59Q/RcGjbG3nFZEJH0zjA0JqsX37TPp61tct7Xg+47RdbVlY+4rTr0q06TPXJPg5KZztiUM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706463538; c=relaxed/simple; bh=IjQ/1TqkmYZebuFP5yVrH0wPzR/hJ4PTWRo5b1Q6T2c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=T4/u15/DD5RbdjXE95ES8QrGcGJb7csQKU7j/sp3gKLirl47jl9z1nbi36avFWR3UWVsOsVi01YElXKpIsxxU5VBy5Ep+UK2O8cXiY1Y/GuZBf6ChS+fyNWZ68lfX3ytLrwt0PLhGxXAJTMlgl5Mld9FacJS6vx+XuTTkYz6gm4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PC3NU5LA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PC3NU5LA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0482C433F1; Sun, 28 Jan 2024 17:38:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706463537; bh=IjQ/1TqkmYZebuFP5yVrH0wPzR/hJ4PTWRo5b1Q6T2c=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PC3NU5LACNJBxfpFA7Iuka8V4DlexS01lk6nHfhY4crAXEFKzph7Ea3BMTKdDD8OU mN0nDgRh9teIeu//jlOYOwekqTTDbwKc3xEPVqrDR9n0vT1AYEcmtwEOIUqMBC7Z4d vQwisJJsADIkEZVg94tY4Dec1c+vNcjVl7nZNr+Q5hogO/oqt/bTOOY395ZZSjdXNj 5passx4f1Up7lxWhDBEbH013lW88itoR4B+GYlKvw6yxZoLsuR4VJ+vL2B4wFoAu14 be8baMLhrfXYunbzdQ9OVGbzNRubG7bUhP7r91SSXDkuPG9Z2uk6lFmMSA9WlQ9DpM 2hRy93oGsUtUw== Date: Sun, 28 Jan 2024 17:38:52 +0000 From: Conor Dooley To: Farouk Bouabid Cc: Greg Kroah-Hartman , Jiri Slaby , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner , Rob Herring , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, quentin.schulz@theobroma-systems.com Subject: Re: [PATCH v4 3/6] dt-bindings: serial: add binding for rs485 rx-enable state when rs485 is disabled Message-ID: <20240128-vagabond-mutilator-cf8dc6ac8a41@spud> References: <20240126-dev-rx-enable-v4-0-45aaf4d96328@theobroma-systems.com> <20240126-dev-rx-enable-v4-3-45aaf4d96328@theobroma-systems.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="DzRBhgrdidHhTC1B" Content-Disposition: inline In-Reply-To: <20240126-dev-rx-enable-v4-3-45aaf4d96328@theobroma-systems.com> --DzRBhgrdidHhTC1B Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jan 26, 2024 at 03:55:12PM +0100, Farouk Bouabid wrote: > RS485 can have a receiver-enable gpio (rx-enable-gpios). When rs485 is > enabled, this gpio, if provided, must be driven active while receiving. > However when RS485 is disabled this gpio should not have an undefined > state. In that case, as DE and RE pins can be connected both to this gpio, > if its state is not properly defined, can cause unexpected transceiver > behavior. > This binding depend on rx-enable-gpios to be implemented. Why do you need a dedicated property for this when there exists a device specific compatible for the uart on both of the affected rockchip systems? Thanks, Conor. >=20 > Signed-off-by: Farouk Bouabid > --- > Documentation/devicetree/bindings/serial/rs485.yaml | 5 +++++ > 1 file changed, 5 insertions(+) >=20 > diff --git a/Documentation/devicetree/bindings/serial/rs485.yaml b/Docume= ntation/devicetree/bindings/serial/rs485.yaml > index b64577036b5c..4c79dfaaf460 100644 > --- a/Documentation/devicetree/bindings/serial/rs485.yaml > +++ b/Documentation/devicetree/bindings/serial/rs485.yaml > @@ -55,6 +55,11 @@ properties: > description: GPIO to handle a separate RS485 receive enable signal > maxItems: 1 > =20 > + rs485-rx-enable-inactive-when-rs485-disabled: > + description: rx-enable GPIO is not active when RS485 is disabled. If= missing, active-state > + is assumed. > + $ref: /schemas/types.yaml#/definitions/flag > + > rs485-term-gpios: > description: GPIO pin to enable RS485 bus termination. > maxItems: 1 >=20 > --=20 > 2.34.1 >=20 --DzRBhgrdidHhTC1B Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZbaRLAAKCRB4tDGHoIJi 0lVcAP9p7fg8n4e6rLO8EL2Eb1sSnS3GQtn1fONEOpidqgF31AEAvoJXIDhzhnRF r/P/IvBUvRkQTjXM4O4aoPKsdLrOQwM= =9qkJ -----END PGP SIGNATURE----- --DzRBhgrdidHhTC1B--