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_PASS,URIBL_BLOCKED autolearn=ham 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 04A27C282D7 for ; Wed, 30 Jan 2019 15:08:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA9542083B for ; Wed, 30 Jan 2019 15:08:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548860934; bh=7tSXuv1G3q0TZTT11mY3TM9600zhP/Lt29G6XlH6Kvg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=A/xhLH1joXru9t3cVmvKGx2m9Yb1Uh37IiSI698CjbpJ+opc93ptgoxxdBTPyB3oi ZVTg/tVlLAQzRz5aNfOv41cMSkqZ+aq9eU99/JwepuBAhzVL1uvf7qovTKMYvT+6Te ENBvy+IzEB3YMIbx7S5PZmiXN/u+zIQv5fsj3HOQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731618AbfA3PIx (ORCPT ); Wed, 30 Jan 2019 10:08:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:55760 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731596AbfA3PIu (ORCPT ); Wed, 30 Jan 2019 10:08:50 -0500 Received: from bbrezillon (91-160-177-164.subs.proxad.net [91.160.177.164]) (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 2A6F720989; Wed, 30 Jan 2019 15:08:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548860929; bh=7tSXuv1G3q0TZTT11mY3TM9600zhP/Lt29G6XlH6Kvg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=zJa+P08V6zahu54Z+HGd75lTdIj/T+74SYRgRGPlnEWi6yJXfEbdzChLO00T4VR5j GrnCi/uWar3GTTSFFbEhKAOKmjZ1mxcmpjzcVOobcDZJZztW9eWlzzw+sloSxNCZj6 Y9U/CZj6ahHYenu5hXpbzPDKnnWTWHEQUnkIsdtw= Date: Wed, 30 Jan 2019 16:08:39 +0100 From: Boris Brezillon To: Greg Kroah-Hartman Cc: Geert Uytterhoeven , Geert Uytterhoeven , Arnd Bergmann , MTD Maling List , Nguyen An Hoan , Linux Kernel Mailing List , linux-spi Subject: Re: [PATCH v2 0/2] eeprom: at25: SPI transfer improvements Message-ID: <20190130160839.55f99e63@bbrezillon> In-Reply-To: <20190130145054.GA990@kroah.com> References: <20190118140525.29189-1-geert+renesas@glider.be> <20190118230740.44239fcf@bbrezillon> <20190130145054.GA990@kroah.com> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Greg, On Wed, 30 Jan 2019 15:50:54 +0100 Greg Kroah-Hartman wrote: > On Tue, Jan 29, 2019 at 08:02:37PM +0100, Geert Uytterhoeven wrote: > > Hi Boris, > > > > On Fri, Jan 18, 2019 at 11:07 PM Boris Brezillon wrote: > > > Did you consider converting this driver to spimem? Looks like the > > > protocol used to communicate with the memory resembles the one used on > > > SPI NANDs/NORs and fits pretty well in the spi_mem_op representation. > > > > > > By doing this conversion you'd allow people to connect an AT25 EEPROM > > > to an advanced SPI controller that does not support regular SPI > > > transfers and you wouldn't have to forge SPI messages manually. > > > > > > Here is a patch (only compile tested) doing that. The diffstat is not in > > > favor of this conversion, but I find the resulting code cleaner and more > > > future proof. > > > > Thanks, seems to work fine, with the 512-byte 25LC040 I have! > > > > Tested-by: Geert Uytterhoeven > > > > I did notice that the first two-byte transfer (command+offset) of each > > message is now split in two one-byte transfers, though. > > Ok, I'll drop this patch series and wait for the updated version to be > sent out :) I'd like to further simplify the patch by using the recently introduced devm_spi_mem_dirmap_create() function (queued to Mark's spi/for-5.1 branch), which means I'll have to wait v5.1-rc1 before sending a new version. I'll let you decide if it's worth applying Geert's patches in the meantime. Regards, Boris