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 EE92EC433E0 for ; Sat, 13 Jun 2020 19:33:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C0AEC207BC for ; Sat, 13 Jun 2020 19:33:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592076818; bh=sxfke0HVIrZ0Ee3QK78MJ2nbLuoAzvTstF2b/37FDg0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Ak2beXX4NxYp+/rVgdTQy2PrTMu1m2Ta7LKRN5Tpm1Cqkvhw9a8QFJ5fyVBJhnF48 LU0iNlGlNhgt1w0ndc3I/CXJveBc/WQqfbGZuJFNYR56OycxtlKzTqX3UyxVTNjLmB kL56zW4tksLWCdyGLKCrVJgi2UBstXvQeF97kGyw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726533AbgFMTdi (ORCPT ); Sat, 13 Jun 2020 15:33:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:51894 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726304AbgFMTdi (ORCPT ); Sat, 13 Jun 2020 15:33:38 -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 C51CD2074D; Sat, 13 Jun 2020 19:33:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592076817; bh=sxfke0HVIrZ0Ee3QK78MJ2nbLuoAzvTstF2b/37FDg0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VVCBr7wxEtTNNSHKGtmi/LMJ171KCprJJf2qu54CGTZoL84mlUtDs/MeLURExAnDw lGRU17f5R3hgsceWK3QOJiEp5WYQTT3x955bV6OLtX/XKYvZjuV+UohsKdGtVsXlPH j08KqMCFV6J6SJof4LALF/tn+klb3HnZ9J1TX2+A= Date: Sat, 13 Jun 2020 21:33:33 +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: <20200613193333.GA6289@kunai> References: <20200613150751.114595-1-marex@denx.de> <20200613150751.114595-5-marex@denx.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="lrZ03NoBR/3+SXJZ" Content-Disposition: inline In-Reply-To: <20200613150751.114595-5-marex@denx.de> Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --lrZ03NoBR/3+SXJZ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi Marek, On Sat, Jun 13, 2020 at 05:07:51PM +0200, Marek Vasut wrote: > Transferring multiple messages via XIIC suffers from strange interaction > between the interrupt status/enable register flags. These flags are being > reused in the hardware to indicate different things for read and write > transfer, and doing multiple transactions becomes horribly complex. Just > send a single transaction and reload the controller with another message > once the transaction is done in the interrupt handler thread. Do we still get a repeated start between messages of a transfer? Or will it be a STOP/START combination? Happy hacking, Wolfram --lrZ03NoBR/3+SXJZ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIyBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAl7lKgoACgkQFA3kzBSg KbYUeg/4rqQELHp535SCLVG48KLJSBdCC1S4/H04G3fFWdZ83d3BPjiHNVfOdjtt COQfuJ7wg7GwRVzz/8Q/PBbjDJJYJPvBbixK04LlRSWhBGr3mt9wMZ7f016rOiHj 1/Y5jeGhOShrnt4CZn5CjqlDTlQIXryFKfT8nKx5c2cQtlW4Kh0tdB2BkGZCKyM9 o2YZXBarsdodWZUCbCLto5cB5DbreoGvI2GDxaMhFZnh7iBKBznxS+OJHznpRDvH 9iNQhbBs0V5nThIBdiLQ6zcHlHGjKTZhBmU47TWiwGhsguBi8hG3Y+8oUsDuJNFK MNS05dqqzl13x48j531gDyrPwMWnYUMThLsmjQG/6JMb4mIMR+No0tt2HY4OlSA/ 2I9PiFHTDCtllHXLaOPCI9arfquPNhJ65Z66TIogq2ippLsHhDHiMBFWn+A+7+gH 8mC8XqsaBNIViqudgmShJZ971VNTyNDLlWvvnu/vXVSUQL1rVnXAv4f5sA5aikL1 0+p8rZvU2uwW52LHYkIqY/Ikq6p4+yex60G4Vbl8rhjIZL/7/QeLpDh0jnJLx6g0 9ZWG0ya8PZ0Z84oXuLGXSlLQAk5Se4Qf4ZZ1+joHqlajumiaz8+DJXAxmG+te7NR ZfmVko54VA6YxsY2vCcp2ji2nyknOCERtSGvaorkaNQbDxx4mg== =JFmd -----END PGP SIGNATURE----- --lrZ03NoBR/3+SXJZ--