Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.33 as permitted sender) client-ip=23.128.96.33;
Received-SPF: Pass (protection.outlook.com: domain of amd.com designates
 165.204.84.17 as permitted sender) receiver=protection.outlook.com;
 client-ip=165.204.84.17; helo=SATLEXMB03.amd.com; pr=C
From:   Manikanta Guntupalli <manikanta.guntupalli@amd.com>
To:     <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>
CC:     <radhey.shyam.pandey@amd.com>, <srinivas.goud@amd.com>,
        <shubhrajyoti.datta@amd.com>, <manion05gk@gmail.com>,
        Manikanta Guntupalli <manikanta.guntupalli@amd.com>
Subject: [PATCH V2 1/2] dt-bindings: Add optional gpio property to uartps node to support rs485
Date:   Wed, 11 Oct 2023 20:26:01 +0530
Message-ID: <20231011145602.3619616-2-manikanta.guntupalli@amd.com>
In-Reply-To: <20231011145602.3619616-1-manikanta.guntupalli@amd.com>
References: <20231011145602.3619616-1-manikanta.guntupalli@amd.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Oct 2023 14:56:18.6902
 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: 912856ee-f516-46e3-151c-08dbca6a39c6
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB03.amd.com]
X-MS-Exchange-CrossTenant-AuthSource: SN1PEPF0002636D.namprd02.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Anonymous
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB8518
X-Spam-Status: No, score=2.7 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED,
	DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,
	MAILING_LIST_MULTI,RCVD_IN_SBL_CSS,SPF_HELO_NONE,SPF_PASS autolearn=no
	autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Wed, 11 Oct 2023 07:56:40 -0700 (PDT)
X-Spam-Level: **

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 shorts 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

xlnx,phy-ctrl-gpios is optional property, because it is not required
for uart console node.

Signed-off-by: Manikanta Guntupalli <manikanta.guntupalli@amd.com>
---
Changes for V2:
Modify optional gpio name to xlnx,phy-ctrl-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 a8b323d7bf94..cf8ef55ba210 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
 
+  xlnx,phy-ctrl-gpios:
+    description: Optional GPIO to control transmit/receive on RS485 phy
+      in halfduplex mode.
+    maxItems: 1
+
 required:
   - compatible
   - reg
@@ -55,6 +60,7 @@ required:
 
 allOf:
   - $ref: serial.yaml#
+  - $ref: rs485.yaml#
   - if:
       properties:
         compatible:
-- 
2.25.1