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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,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 3BA24C433E1 for ; Fri, 22 May 2020 14:57:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 14B53207BC for ; Fri, 22 May 2020 14:57:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="RJh8B/6r" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730713AbgEVO5t (ORCPT ); Fri, 22 May 2020 10:57:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731342AbgEVO5r (ORCPT ); Fri, 22 May 2020 10:57:47 -0400 Received: from mail-io1-xd43.google.com (mail-io1-xd43.google.com [IPv6:2607:f8b0:4864:20::d43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DAE2C061A0E; Fri, 22 May 2020 07:57:47 -0700 (PDT) Received: by mail-io1-xd43.google.com with SMTP id j8so11576754iog.13; Fri, 22 May 2020 07:57:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=4E93R1F4OMg9K2XLuc0UwI5BfmV/kB8DZ8DcAqlj91Q=; b=RJh8B/6rHjjbkuji4u+fJ26zGQ2weYdBP8O87V6gBC0R3uO3Cxuxwia4xEC5fiQpVd BVao3bcj3EENB6cqKTKGBQu174xQRasXIfU4q+TkCRor9QpUGn/bNvOhtPgxnpksjF4z 3fsMvYjJfJTHISaJ3cUFiRzeDfD7i3e9PZi6fj0SkJEmzk7TEWtsxWUY/iwJxQpOJ2R4 T9SYcuC5mIwu3BPDv9d/KbkENTdJY9raVR0/065zsK9r46jPvzUkAxudp8zmyxpkPzW8 Mh3IcqqBDWoU5MuQNyfGmuqSaUQzuiK4qAbocc1kDDt5QghsG+0LEtcX/A9knBg3T5Ef pvLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4E93R1F4OMg9K2XLuc0UwI5BfmV/kB8DZ8DcAqlj91Q=; b=A8HAwTy87BkFgPBjC5bZ9vWtb7A3CPFHn+mypgqLRaGzLTcx6LaszXDLvCh6yvCPH3 jM0X6Pmjspr3xcYqx5Qc9pSxKvOa+dGUcCBYjfrACWASbhtJpM8qV5dDph3tN3LxvBDc AvvzBnnTteSNlm4wekzi3T/9hnfHfmu4HMiW+J4+GzJPC7gjcRi6GRJHNl2Y/cnghQ80 PfJJdgnbmq+2OKnpomNjtoe8YQ7q6NjzChJtqOt4NWlzqtZLjnmj7Mpz6VZL817Ck+7x 5Yquj91e6nEwtkPCXUgXSxPT71obhiQ8eKgFRYqN84MWFnZJPSAzqgogMxp4LpVOrORb uflQ== X-Gm-Message-State: AOAM530iIcwXx0ow2TCegm1QtUIfThknF51Av7FqPMYg08j47eKUk3lM O44wTQCrrxMR56+s3QkiFOmGVGrtM5veU/fwpu4= X-Google-Smtp-Source: ABdhPJzIBFSsXPwSSCGw73KtvrqDIXMGD/+GjvxVG0mSEkFCp7BWwg4nqAvzm+UoIsx0S8/uDt84GiJO2N2vFmJg7HM= X-Received: by 2002:a05:6602:2ac9:: with SMTP id m9mr3461002iov.68.1590159466755; Fri, 22 May 2020 07:57:46 -0700 (PDT) MIME-Version: 1.0 References: <1589800165-3271-1-git-send-email-dillon.minfei@gmail.com> <1589800165-3271-4-git-send-email-dillon.minfei@gmail.com> <20200522113634.GE5801@sirena.org.uk> In-Reply-To: <20200522113634.GE5801@sirena.org.uk> From: dillon min Date: Fri, 22 May 2020 22:57:10 +0800 Message-ID: Subject: Re: [PATCH v4 3/8] spi: stm32: Add 'SPI_SIMPLEX_RX', 'SPI_3WIRE_RX' support for stm32f4 To: Mark Brown Cc: Rob Herring , p.zabel@pengutronix.de, Maxime Coquelin , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Alexandre Torgue , thierry.reding@gmail.com, Sam Ravnborg , Dave Airlie , Daniel Vetter , Michael Turquette , Stephen Boyd , Linux ARM , linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, "open list:DRM PANEL DRIVERS" , linux-clk Content-Type: text/plain; charset="UTF-8" Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org hi Mark, Thanks for reviewing. On Fri, May 22, 2020 at 7:36 PM Mark Brown wrote: > > On Mon, May 18, 2020 at 07:09:20PM +0800, dillon.minfei@gmail.com wrote: > > > 2, use stm32 spi's "In full-duplex (BIDIMODE=0 and RXONLY=0)", as tx_buf is > > null, we must add dummy data sent out before read data. > > so, add stm32f4_spi_tx_dummy() to handle this situation. > > There are flags SPI_CONTROLLER_MUST_TX and SPI_CONTROLLER_MUST_RX flags > that the driver can set if it needs to, no need to open code this in the > driver. Yes, after check SPI_CONTROLLER_MUST_TX in drivers/spi/spi.c , it's indeed to meet this situation, i will try it and sumbmit a new patch. thanks. best regards Dillon