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dkim=none (message not signed) header.d=none;dmarc=fail action=none header.from=foss.st.com; Received-SPF: Fail (protection.outlook.com: domain of foss.st.com does not designate 164.130.1.59 as permitted sender) receiver=protection.outlook.com; client-ip=164.130.1.59; helo=smtpO365.st.com; Received: from smtpO365.st.com (164.130.1.59) by AMS1EPF00000041.mail.protection.outlook.com (10.167.16.38) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.25.13 via Frontend Transport; Mon, 11 May 2026 07:10:32 +0000 Received: from STKDAG1NODE2.st.com (10.75.128.133) by smtpo365.st.com (10.250.44.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.35; Mon, 11 May 2026 09:14:19 +0200 Received: from [10.48.87.127] (10.48.87.127) by STKDAG1NODE2.st.com (10.75.128.133) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.35; Mon, 11 May 2026 09:10:30 +0200 Message-ID: <92a8e53e-412a-4475-89dc-62caf12e8c56@foss.st.com> Date: Mon, 11 May 2026 09:10:28 +0200 Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v13 3/4] gpio: rpmsg: add generic rpmsg GPIO driver To: Mathieu Poirier CC: Beleswar Prasad Padhi , Shenwei Wang , Andrew Lunn , Linus Walleij , Bartosz Golaszewski , Jonathan Corbet , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Bjorn Andersson , Frank Li , Sascha Hauer , Shuah Khan , "linux-gpio@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Pengutronix Kernel Team" , Fabio Estevam , "Peng Fan" , "devicetree@vger.kernel.org" , "linux-remoteproc@vger.kernel.org" , "imx@lists.linux.dev" , "linux-arm-kernel@lists.infradead.org" , dl-linux-imx , Bartosz Golaszewski References: <472f85bd-42c2-40c6-abfd-b76924797069@ti.com> <21de8440-adf7-454b-acfc-06e50882e075@ti.com> <4c526816-b127-43e7-86e9-eee4dc1152bc@foss.st.com> <268f8e00-91bc-43ea-ba95-077cf859e7f3@ti.com> <9e2492d3-8753-46c7-8db6-5f1a80b4f2e9@foss.st.com> <6917e3d7-8c6c-4e63-8eca-5308621ec3e8@foss.st.com> Content-Language: en-US From: Arnaud POULIQUEN In-Reply-To: Content-Type: text/plain; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 2ag6a8+a2dCUMeGxPVIFyf8qRS8Si7BYvPj9A3w7oq7Mg1M5WVUHy0oKUMALYR6uQIsdaiaQrfrRv0TNKOQTaEahq5ok3atJdSrqnF6mR+dHc/fIRIMZEFKwIEwmRaYpDAY+GdsP35KEuhTZQbwVAuAF2F0fe54jBwfuB/hP36n0vailt5MyD/OYOTrigD4d1Gz3Zx9UxswEvkjOsO585hWVDIW6VEMteFB0L+aae0urTipKH/y9mYU7sE9UilpBIgwukeB9QN3+SJSIakxRg+PI+lt+SWYwAeSuyfNQrlIQw/ZqwZdH77YowZ+iK9ocJPXbGIn6alL84aeCIeoZDl+517ther3HuiBP6oPxREQzNEhHyyP5YZY5XOlTVQMQnXcGPM/nGQgSEEvK53o1JWSn3Z/Ba8/Rl0xom0ujCCSZbaBC3xQPAfsNkxLyB4gR X-OriginatorOrg: foss.st.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 May 2026 07:10:32.6847 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 9319f76a-efdb-4a3d-2e98-08deaf2c6433 X-MS-Exchange-CrossTenant-Id: 75e027c9-20d5-47d5-b82f-77d7cd041e8f X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=75e027c9-20d5-47d5-b82f-77d7cd041e8f;Ip=[164.130.1.59];Helo=[smtpO365.st.com] X-MS-Exchange-CrossTenant-AuthSource: AMS1EPF00000041.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: GVXPR10MB8664 Hello Mathieu, [...] >> >> A third option would be a combination of both approaches: instantiate the >> device using the same name service from the remote side, as done in >> rpmsg-tty. In that case, a get_config message, or a similar mechanism, would >> also be needed to retrieve the port information from the remote side. >> > > I'm not overly fond of a get_config message because it is one more thing we > have to define and maintain. > > Arnaud: is there a get_config message already defined for rpmsg_tty? No there isn't. Regards, Arnaud > > Beleswar: Can you provide a link to a virtio device that would use a get_config > message? > >> Tanmaya also proposed another alternative based on reserved addresses. >> >> At this point, I suggest letting Mathieu review the discussion and recommend >> the most suitable approach. >> >> Thanks, >> Arnaud >> >>>> >>>> At the end, whatever solution is implemented, my main concern is that the >>>> Linux driver design should, if possible, avoid adding unnecessary complexity >>>> or limitations on the remote side (for instance in openAMP project). >>> >>> >>> Yes definitely, I want the same. Feel free to let me know if this does >>> not suit with the OpenAMP project. >>> >>> Thanks, >>> Beleswar >>> >>>> >>>> Thanks, >>>> Arnaud >>>> >>>> >>>>> So Linux does not need to send the port idx everytime while sending a >>>>> gpio message anymore. >>>>> >>>>> Thanks, >>>>> Beleswar >>>>> >>>>> [...] >>>>> >>>> >>