Re: [PATCH] ARM: dts: at91: add serial MFD sub-node for usart
From: <Codrin.Ciubotariu@microchip.com>
Date: 2020-10-30 14:24:31
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On 30.10.2020 15:38, Nicolas Ferre wrote:
On 30/10/2020 at 12:07, Codrin Ciubotariu wrote:quoted
The "atmel,at91sam9260-usart" driver is a MFD driver, so it needs sub-nodes to match the registered platform device. For this reason, we add a serial subnode to all the "atmel,at91sam9260-usart" serial compatible nods. This will also remove the boot warning: "atmel_usart_serial: Failed to locate of_node [id: -2]"I don't remember this warning was raised previously even if the MFD driver was added a while ago (Sept. 2018). I would say it's due to 466a62d7642f ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes") which was added on mid August and corrected with 22380b65dc70 ("mfd: mfd-core: Ensure disabled devices are ignored without error") but maybe not covering our case.
Well, it's not covering our enabled devices.
So, well, I don't know what's the best option to this change. Moreover, I would say that all other USART related properties go into the child not if there is a need for one. Lee, I suspect that we're not the only ones experiencing this ugly warning during the boot log: can you point us out how to deal with it for our existing atmel_serial.c users?
My understading is that platform devices registered by MFD should have a correspondig DT node. The parrent properties are also available for the other usart device (usart-spi), so I think we should keep them in the parrent. Best regards, Codrin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel