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=-3.0 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_GIT 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 5638CC282C0 for ; Fri, 25 Jan 2019 11:44:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A41F218E2 for ; Fri, 25 Jan 2019 11:44:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=norrbonn-se.20150623.gappssmtp.com header.i=@norrbonn-se.20150623.gappssmtp.com header.b="hgRyAVQR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727868AbfAYLoe (ORCPT ); Fri, 25 Jan 2019 06:44:34 -0500 Received: from mail-lf1-f68.google.com ([209.85.167.68]:35406 "EHLO mail-lf1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726095AbfAYLoe (ORCPT ); Fri, 25 Jan 2019 06:44:34 -0500 Received: by mail-lf1-f68.google.com with SMTP id e26so6719534lfc.2 for ; Fri, 25 Jan 2019 03:44:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=norrbonn-se.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1uZgeytfHcFfoxxwaJPRe+nMKCIYtTyciuS0VyMLAl0=; b=hgRyAVQR/JxBzSyWetarj8knMgSFD/WDjVWg2isDKSBIcHphNqDQ6YKu0fQrTStlMB OJs07Os9s+jYwPXfnunj0E6FcqaR8dF9uV/80UzoXBwx96kR28irhLy6ya3hrVoLdpNd vQP/7LPfKv5xGe8crcqx7Lvok3M3alOkkcVsDgPdQqXjGr5cAQdWt6a5BzIF4fO6Ue2E huIAq4YljM0u4Nbo1MQL+pthruIv8YKTrmY5MLHPAvOk43vM8z03RX3iyvGyrobUadz9 Y7zxY+zH9yWQeBraXCCv9Lh3t/4DrBxsF/v/nrmrUsE908AHfEojZjvJqPf10laOE6Sp bQOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1uZgeytfHcFfoxxwaJPRe+nMKCIYtTyciuS0VyMLAl0=; b=dLu2In+HP5Dh9rArmMzz5AmvrD0PYfoVG5yGb4QCvbn7duKrCFM6QAdf9bWJlgPyVx wHed9R+V6KG2Fugg3dTbyHCF9Z83DxZzO1lhMzS76zswpXuKSc7bs5uDJRi8TGIsAjCT 5kOMvNJCXDZ7rSx1QiTmQI8lYKA7tpuw/vV34/+SAHWbX8AqxuvPiqsdxDl9b45PoALw togQqdAJe4LrS3+EzRaOuN1V1e6HGRMUvG/pqegjf/ouFUBzSKJD4I5fSZ9vusMzseAp reOJ9+sCpRzVP4bFsyShOAHcbQMsEsnndXlJyiIyTBA8tcWDE9VVSy7xKKDPo/nzue8f bfyA== X-Gm-Message-State: AJcUukdKHA0XnKaXaet05zIz7AphLNkmtwEZbuEbetlPE2ycLdnBo18O Zr+zliwvKGFblaMjVVHtXJm60BhkRGA= X-Google-Smtp-Source: ALg8bN7V9lQNIdgdU/gKYAG2vuhxH/ygZj73KJNHy/qQ8qoTx/5/KuI/oqFD2D3HUAbQwymgN22O/g== X-Received: by 2002:a19:7352:: with SMTP id o79mr8668259lfc.104.1548416672309; Fri, 25 Jan 2019 03:44:32 -0800 (PST) Received: from mimer.lan (h-29-16.A159.priv.bahnhof.se. [79.136.29.16]) by smtp.gmail.com with ESMTPSA id l3-v6sm1490962ljg.21.2019.01.25.03.44.31 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 25 Jan 2019 03:44:31 -0800 (PST) From: Jonas Bonn To: linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Cc: Jonas Bonn Subject: [PATCH 0/2] spi: support inter-word delays Date: Fri, 25 Jan 2019 12:44:27 +0100 Message-Id: <20190125114429.20066-1-jonas@norrbonn.se> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This short series adds support for SPI inter-word delays and configures the spi-atmel driver to honour the setting. Some SPI slaves are so slow that they are unable to keep up even at the SPI controller's lowest available clock frequency. I have such a configuration where an AVR-based SPI slave is unable to feed the SPI bus fast enough even the SPI master runs at the lowest possible clock speed. Jonas Bonn (2): spi: support inter-word delay requirement for devices spi-atmel: support inter-word delay Documentation/devicetree/bindings/spi/spi-bus.txt | 1 + drivers/spi/spi-atmel.c | 11 ++++++----- drivers/spi/spi.c | 4 ++++ include/linux/spi/spi.h | 1 + 4 files changed, 12 insertions(+), 5 deletions(-) -- 2.19.1