From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CFC4EC433ED for ; Fri, 7 May 2021 15:32:56 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 26CD061469 for ; Fri, 7 May 2021 15:32:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 26CD061469 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=5gV8VS/78L3cdoMnlPZ5OM1N2dzTx0iYopaDsfXCTEk=; b=WYgc/8HnXGUwI6v27U4LS/vmy G24w0r4BNqHr8jdLCl9AOU/W56i2yBFHEv5Rjl6gEKabAXZoqwtqWYoQ0T4JzO9QgcGL9XravRcoc 2bqBp2XHzKT0WISwwjY5ho5EhgtQdbYMAim9BBJd9Cknk/2r+Xp+hMheGkNd7MrCAZUnrh/q/2azl T3wDHAekKJtN2JoH108ATdYWWtTOK/z0RJZAKohpNesoMy9M9sbFc1ZNxA5G4Q4V01dXFdenbBKmL 6EBa3mb3FzbLglmOXSGhf9qTqF8EBdSCoYxH6/3iwMPMAEk3hutuzsYiCIKoyatYgEAadbWNutYlK 3vRq78f0Q==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lf2Sd-007QhQ-Fa; Fri, 07 May 2021 15:32:15 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lf2Sb-007Qh3-LC for linux-mtd@desiato.infradead.org; Fri, 07 May 2021 15:32:13 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=O3zHx8gGy8AU49D+Cnr2TBWRAoXneuMN59DU/Ks3vhs=; b=kmuzNOQo86QZuONmxWVJTCgytY Ox/J0y/Cy20ja8npwmOE8P2SFF6tpizqcqDi6t/PZEHnMBI4Q3zw/SEpqR+ENI6/DjGJfpodHBpZF uYwQY6tWSUo2B8s21gDMdhpE9o+LPbxnLz8V2NITE1CqCAp3l1nBBF+WMiNeSDVUxVOneFaqScBzL 0R1pl/DNze36Zmr9DJxzmQM3LbQ6bOgRp0tt4DpPSyeCD/oIrrkr3hohyRBzcuyODjGwRABVmAjeS RvDAOE4Egu3cM7Mc7upowLpk572bq6Lokv1+Xkhea+eKIX1thZnFSVDZ7PT8KtKMBkHaOcEjb4QJs qWphOE/Q==; Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lf2SZ-006xut-2S for linux-mtd@lists.infradead.org; Fri, 07 May 2021 15:32:12 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id E3F4B61460; Fri, 7 May 2021 15:32:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1620401530; bh=O3zHx8gGy8AU49D+Cnr2TBWRAoXneuMN59DU/Ks3vhs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RjOYIsvAC5gLtDgOeipF0F06gxKKV6y4oHApV4eIapZor+2Jwj5gHQ1ya1MhHIyme bn61u5vsDc+ZcuMPSOH8v51zHMySSD8emcgVya6okdgrrzXFEwxxa//ImRHWGV1gJl sHauyc5dg4V1lXYoUc+almVuAt38m/6XSH8ERigfRMQ7VQWrj8BibB6n8Q5FsVZ/cm kvZ+evUd1a3JB8VP9Zh54XD9EHXQxm4XwVvCPMJ7P1rOOdwGkb7AAM04G8tAH2OFlK 0eu0oPZlAUEz/mqY+wnHxXUmeLJj3RCmP9mID3ZsScJvArFw7MoNkFYFTMyEy+EEP3 QZZHlc+e1zE9A== Date: Fri, 7 May 2021 16:31:32 +0100 From: Mark Brown To: Pratyush Yadav Cc: Tudor Ambarus , Michael Walle , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Subject: Re: [PATCH 4/6] spi: spi-mem: reject partial cycle transfers in 8D-8D-8D mode Message-ID: <20210507153132.GC6383@sirena.org.uk> References: <20210506191829.8271-1-p.yadav@ti.com> <20210506191829.8271-5-p.yadav@ti.com> <20210507125533.GA6383@sirena.org.uk> <20210507135631.maue7gorfzsv4qpk@ti.com> MIME-Version: 1.0 In-Reply-To: <20210507135631.maue7gorfzsv4qpk@ti.com> X-Cookie: Postage will be paid by addressee. User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210507_083211_176038_D4C48A93 X-CRM114-Status: GOOD ( 10.11 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============6424216153090011107==" Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org --===============6424216153090011107== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="/e2eDi0V/xtL+Mc8" Content-Disposition: inline --/e2eDi0V/xtL+Mc8 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, May 07, 2021 at 07:26:33PM +0530, Pratyush Yadav wrote: > Patches 2 and 3 are a slightly different matter. They add an extra=20 > register write. But most controllers I've come across don't support=20 > 1-byte writes in 8D mode. It is likely that they are sending=20 > bogus/undefined values in the second byte and deasserting CS only after= =20 > the cycle is done. So they should _in theory_ change undefined behaviour= =20 > to defined behaviour. > Still, they introduce an extra register write. I'm not sure how=20 > risk-tolerant you want to be for stable backports. I will leave the=20 > judgement to you or Tudor or Vignesh. Ah, given that if nobody's seeing any issues I'd probably just hold off there TBH. --/e2eDi0V/xtL+Mc8 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmCVXVQACgkQJNaLcl1U h9B8HAf9GZh6wXoQyIjqchDq4kgwLgCdMTMAnT1LjmrcRaeTiLr30MVfyjO+eLan tCZYatA9w4eVKm2NbXI1G0JqZ+ZlmuGlgFEb1kRrSdWn/A6rUF0fHlCjygq6wQTR GBqZ4wWImXKcry+Wc8GsZWggtV7XCkQYE3bp4l2QfXkhFtASgPkSYtLfYbOOKjOP 1Xpc4kqpfpaZIRDPJKqwTykeJaeTxY+T3Lfz/IUjFUa9mtr0RC6FjnA5+ekboY4C pEMICHbnrt2WDRAk6HXqypb5N+HJ2V84XLi3Q/uMjFlgC4+2lLe/OEIkgzGDJns3 8/2LTp0aNJ+CgvTMYbnSmdorhvF2wA== =+ofb -----END PGP SIGNATURE----- --/e2eDi0V/xtL+Mc8-- --===============6424216153090011107== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/ --===============6424216153090011107==--