Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1BFAC433F5 for ; Tue, 23 Nov 2021 10:28:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235482AbhKWKby (ORCPT ); Tue, 23 Nov 2021 05:31:54 -0500 Received: from mail.kernel.org ([198.145.29.99]:46798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235327AbhKWKbx (ORCPT ); Tue, 23 Nov 2021 05:31:53 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id E3C1360F24; Tue, 23 Nov 2021 10:28:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637663325; bh=aCyFsSv+caYDKha71mKtcOg3uvXod4Die69+RoIR32A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aR+RJldWPXGGZ4UH3byTcFFJXcOkHE6AYM/JPnMImOuKiWNcy+yRi9tkuLtmfCWNW bFOYRlDuvaqbghjxR/BqH2tt1n2fmYJ68oKaqunDUtY+wOCBTSuIWQ56sPGT332scu L+EJhboNB6RYDDXlvJt0NDPDto3gX0thGO/luEv3tooNM0eqhRIGoEZgjT+bcnoAX+ /qJhVIe5L9lSRswAoBQ3mP+VeMVjBrVgLUD9I+8HKwDBu9488zmI62hZgZAo+aUvGP VTjMp9EJBCJIc8tym3o0h+Osv+opkBEOiIve42MiRJm4gbvbFw8ihRI2GbBYLuS7qv OdStCDtPzctTQ== Date: Tue, 23 Nov 2021 11:28:41 +0100 From: Wolfram Sang To: minyard@acm.org Cc: Oleksij Rempel , Pengutronix Kernel Team , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Manley Subject: Re: [PATCH v2 2/2] i2c:imx: Add an extra read at the end of an I2C slave read Message-ID: Mail-Followup-To: Wolfram Sang , minyard@acm.org, Oleksij Rempel , Pengutronix Kernel Team , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Manley References: <20211112133956.655179-1-minyard@acm.org> <20211112133956.655179-3-minyard@acm.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="3xCL2hZWPLkobz1m" Content-Disposition: inline In-Reply-To: <20211112133956.655179-3-minyard@acm.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --3xCL2hZWPLkobz1m Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Nov 12, 2021 at 07:39:56AM -0600, minyard@acm.org wrote: > From: Corey Minyard >=20 > The I2C slave interface expects that the driver will read ahead one > byte. The IMX driver/device doesn't do this, but simulate it so that > read operations get their index set correctly. =46rom what I understand, the patch is correct but the description may be wrong? AFAIU the patch adds the slave event I2C_SLAVE_READ_PROCESSED to the case when the last byte was transferred. We as the client got a NAK from the controller. However, the byte WAS processed, so the event is ok and not a dummy? --3xCL2hZWPLkobz1m Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmGcwlUACgkQFA3kzBSg KbZGgw/8DlcaJv9fIcLR3la/fnN4Rm2J73zeXFaF4MVb4+SgUHMw9QvOzoMR55oY SjWmja7YASFK0xmIb92pPvVBce6l64BDhmaEPLQwmuvU+QbuOamKX0cYZLjcnHE0 NrMbUtSoG9nIfpO+bcfvLyFuh/y1Nx2eFHplYd2bMz7eO9fESD6jcvXviRQ0bxEB Ex6rtXmMCtzx4FVHq7yQ4hfVAFO89U/7DKkBQ/kQPuDVKPsOgouFOMa1A9zlai/R Mcmn+eVJlbP3WtJzx/yAtsWchlCg/XQJUe0bOjDX+rrrZECEEX8HCpXFWw9bginx tEdKbY1/CCUoXfSeI7qlJi5+MoJkndiCLlisjkagmD40rY4d2L8DxAokC5g1Uqt8 M4BF3mO2l2guhgURuWIguAdpgt13lTXnwrcae2fwvqrtqcjyUMzk5znByjDrAe9P hUhrXeGnkIYU0tCCl8Ciu/Slq739pJzh5dJjSH9Mpsg+zPZJzgjYPbNuN+VPHeWL xgdxK1b3OEcQFrpqtsvcmuJmOpqI4KAGJj3ilAsDNoEgnjhlXhAW5ef/IAjtirqs EkwBRuL+uijrI2FcBuwLTkNl1H4+9ayjVxkzOiD+uad4B6UeVl/w5xqWuDtg31x8 tusF9b34TliUkdiMl4kU4kwV9TmrDforEqbZks4BUmHmyFXoItg= =n2jQ -----END PGP SIGNATURE----- --3xCL2hZWPLkobz1m--