From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 9BD231FCF for ; Sat, 28 Oct 2023 10:59:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from connect.vanmierlo.com (fieber.vanmierlo.com [84.243.197.177]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04ABCB4; Sat, 28 Oct 2023 03:59:35 -0700 (PDT) X-Footer: dmFubWllcmxvLmNvbQ== Received: from roundcube.vanmierlo.com ([192.168.37.37]) (authenticated user m.brock@vanmierlo.com) by connect.vanmierlo.com (Kerio Connect 10.0.2 patch 1) with ESMTPA; Sat, 28 Oct 2023 12:59:28 +0200 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Sat, 28 Oct 2023 12:59:28 +0200 From: m.brock@vanmierlo.com To: Manikanta Guntupalli Cc: git@amd.com, michal.simek@amd.com, gregkh@linuxfoundation.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, linux-serial@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, jirislaby@kernel.org, linux-arm-kernel@lists.infradead.org, radhey.shyam.pandey@amd.com, srinivas.goud@amd.com, shubhrajyoti.datta@amd.com, manion05gk@gmail.com Subject: Re: [PATCH V3 1/2] dt-bindings: Add optional gpio property to uartps node to support rs485 In-Reply-To: <20231024144847.2316941-2-manikanta.guntupalli@amd.com> References: <20231024144847.2316941-1-manikanta.guntupalli@amd.com> <20231024144847.2316941-2-manikanta.guntupalli@amd.com> Message-ID: X-Sender: m.brock@vanmierlo.com Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Manikanta Guntupalli schreef op 2023-10-24 16:48: > Add optional gpio property to uartps node and reference to rs485.yaml > > On Xilinx/AMD Kria SOM KD240 board rs485 connects via TI ISOW1432 > Transceiver device, where one GPIO is used for driving DE/RE signals. > With rs485 half duplex configuration, DE and RE are shorted to each > other, > and at a time, any node acts as either a driver or a receiver. > > Here, > DE - Driver enable. If pin is floating, driver is disabled. > RE - Receiver enable. If pin is floating, receiver buffer is disabled. > > For more deatils, please find below link which contains Transceiver > device(ISOW1432) datasheet > https://www.ti.com/lit/ds/symlink/isow1432.pdf?ts=1682607122706&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FISOW1432%252Fpart-details%252FISOW1432DFMR%253FkeyMatch%253DISOW1432DFMR%2526tisearch%253Dsearch-everything%2526usecase%253DOPN > > rts-gpios is optional property, because it is not required > for uart console node. > > Signed-off-by: Manikanta Guntupalli > --- > Changes for V2: > Modify optional gpio name to xlnx,phy-ctrl-gpios. > Update commit description. > Changes for V3: > Modify optional gpio name to rts-gpios. > Update commit description. > --- > Documentation/devicetree/bindings/serial/cdns,uart.yaml | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/Documentation/devicetree/bindings/serial/cdns,uart.yaml > b/Documentation/devicetree/bindings/serial/cdns,uart.yaml > index e35ad1109efc..7ee305f9a45f 100644 > --- a/Documentation/devicetree/bindings/serial/cdns,uart.yaml > +++ b/Documentation/devicetree/bindings/serial/cdns,uart.yaml > @@ -46,6 +46,11 @@ properties: > power-domains: > maxItems: 1 > > + rts-gpios: > + description: Optional GPIO to control transmit/receive on RS485 > phy > + in halfduplex mode. > + maxItems: 1 > + Why would this be related to RS485? A user could also have a need for a gpio instead of the native pin to be used as normal rts. All RS485 references can be removed. > required: > - compatible > - reg > @@ -55,6 +60,7 @@ required: > > allOf: > - $ref: serial.yaml# > + - $ref: rs485.yaml# > - if: > properties: > compatible: Maarten