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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 CAF60C433DF for ; Sat, 13 Jun 2020 19:42:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7A73207BC for ; Sat, 13 Jun 2020 19:42:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592077344; bh=Y0nUZKpO6R9m396gocd+Bl0IwU3ugpNYW0MEt0NBJgA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=YVKz0OCiElSh/GzICWuMCKJIuDmCu1weIMHn8zV7ST5FyDV2pTzCFwaEX9U3u7hbI 8i3cfZgroaGFK5Yuhe8BfICvfGktYeOFU1STpsaldB7hK+jPn52Qvh985aUgjcCzzM xWESYAc4IAOdqSqddDsZHkrkhUAN1ac3sUSzz1OE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726466AbgFMTmY (ORCPT ); Sat, 13 Jun 2020 15:42:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:55736 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726102AbgFMTmX (ORCPT ); Sat, 13 Jun 2020 15:42:23 -0400 Received: from localhost (p5486c936.dip0.t-ipconnect.de [84.134.201.54]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 66A4D20789; Sat, 13 Jun 2020 19:42:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592077342; bh=Y0nUZKpO6R9m396gocd+Bl0IwU3ugpNYW0MEt0NBJgA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=K0bANh5nYHZOHOO5jAZFdiGlRz8ygTWSjZqDr9vQXXfqE1OAyqcPOwJjTgiMRi1ZX M2CAX92kQzXnL/tTIz5j6DFsLTqckxz9pLAf2Lagaxu/JbZcByYN23H6ozJPvbR4cd 4zBwGykUyXqzELpMAPC+Km3b7VD7pzVS6DmyCfUk= Date: Sat, 13 Jun 2020 21:42:20 +0200 From: Wolfram Sang To: Marek Vasut Cc: linux-i2c@vger.kernel.org, Michal Simek , Shubhrajyoti Datta Subject: Re: [PATCH 5/5] i2c: xiic: Only ever transfer single message Message-ID: <20200613194220.GB6289@kunai> References: <20200613150751.114595-1-marex@denx.de> <20200613150751.114595-5-marex@denx.de> <20200613193333.GA6289@kunai> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="6sX45UoQRIJXqkqR" Content-Disposition: inline In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --6sX45UoQRIJXqkqR Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > >> Transferring multiple messages via XIIC suffers from strange interacti= on > >> between the interrupt status/enable register flags. These flags are be= ing > >> reused in the hardware to indicate different things for read and write > >> transfer, and doing multiple transactions becomes horribly complex. Ju= st > >> send a single transaction and reload the controller with another messa= ge > >> once the transaction is done in the interrupt handler thread. > >=20 > > Do we still get a repeated start between messages of a transfer? Or will > > it be a STOP/START combination? >=20 > Repeated start. Good. That was my high level question. I'll leave the rest of the review then for Michal. --6sX45UoQRIJXqkqR Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAl7lLBwACgkQFA3kzBSg KbbuyA//Vm1vw4CrIxpgZ1y/ZwkkYGQa367go3qRY06uadE3MigcwIADs0EDL7RA kAzhtf5SbvraSDiqlkDGaPrvy7pO8K/lEAZN+lBqjQy8iqV3tDW+7ANeW9fsSu3P fJ5Dcluuwx+TBYd5rdkb+8rYPRvekVNDY3nC6iSbNRe43yvh1K2Yfbhwq7/KRhSO RMt38zW0ny0g0RSZMMqMvwbSHPwckPHK9RukmkqwOLuLivg69Ft1tFO9LcX4qSgQ bnk7qoXZdRaXvjx5TSdLyhphOHIeAYDwtwGTrUyj2+A6++U5yPVlTMwcETSdQ7u8 wWM0Wrmlh7qyvBXNlWR96MUL+noh+Z2t01NOs9ErArnTXeP2ubbSA3ebldnsXeUL IIJhmFeiP1a+R7g8ujSa+/MZP9MjfFWzB4nBpsCtTvHNCeqMiTJgi0qzqIMemUgP bbjlU+5+EOYInTRLCTNvOfMUGPZsKrlDSgRdYIQCDpJXjdzwOC2JJcg3vcyqjt34 wmd+LB1vxHA6yI5aT6u73B5PoS6rQWc+6LfUxpI2xaTXxt/m3SChwhIiB83bYnkO m8KmVAX6YpsGNTOzRi3DN37EM6PCbTLZWkt+hnG0w4LxjtPQpLG68Vi1f/whNbQf 3bV4w2C7x34PRoFk6T3KQFxEnNu6BB4stp88wO92JrFfRCnI2GU= =sWZI -----END PGP SIGNATURE----- --6sX45UoQRIJXqkqR--