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Date: Wed, 19 Mar 2025 18:30:24 -0500
From: Rob Herring <robh@kernel.org>
To: Takahiro Kuwano <tkuw584924@gmail.com>
Cc: Tudor Ambarus <tudor.ambarus@linaro.org>,
	Pratyush Yadav <pratyush@kernel.org>,
	Michael Walle <mwalle@kernel.org>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>, linux-mtd@lists.infradead.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	Bacem Daassi <Bacem.Daassi@infineon.com>,
	Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Subject: Re: [PATCH 2/3] mtd: spi-nor: use rdid-dummy-ncycles DT property
Message-ID: <20250319233024.GA2625856-robh@kernel.org>
References: <20250319-snor-rdid-dummy-ncycles-v1-0-fbf64e4c226a@infineon.com>
 <20250319-snor-rdid-dummy-ncycles-v1-2-fbf64e4c226a@infineon.com>
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In-Reply-To: <20250319-snor-rdid-dummy-ncycles-v1-2-fbf64e4c226a@infineon.com>

On Wed, Mar 19, 2025 at 06:47:44PM +0900, Takahiro Kuwano wrote:
> There are infineon flashes [1] that require 8 dummy cycles for the
> 1-1-1 Read ID command. Since the command is not covered by JESD216
> or any other standard, get the number of dummy cycles from DT and use
> them to correctly identify the flash.

If Read ID fails, then couldn't you just retry with dummy cycles? Or 
would unconditionally adding dummy cycles adversely affect other chips?

Otherwise, add a specific compatible to imply this requirement. Adding 
quirk properties doesn't scale.

Rob