From patchwork Wed Dec 16 22:41:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11978705 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 745FAC0018C for ; Wed, 16 Dec 2020 22:43:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 40A5A233FB for ; Wed, 16 Dec 2020 22:43:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730240AbgLPWnr (ORCPT ); Wed, 16 Dec 2020 17:43:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730250AbgLPWnr (ORCPT ); Wed, 16 Dec 2020 17:43:47 -0500 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66CD9C0611CA for ; Wed, 16 Dec 2020 14:42:34 -0800 (PST) Received: by mail-pg1-x535.google.com with SMTP id n7so18712089pgg.2 for ; Wed, 16 Dec 2020 14:42:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=BPvTnVUDt2kn6sTakfYBUjy6fTGY3iiChEwJjn5yMPk=; b=V+YrL3eDlSpR/G8VTdjzDPz7lurDAsZSM0NDpZYHuVvnphbh3bFnSTxBQ9c6xB2gxh FtwwDesa/1bcdbOeQj4rmElZrpngBmuZxonqT4DwtIJrPM9duEcqkYu0uOL5C5nwC7A2 mOR69YPhn0IgdtAbVmdcEQ0zXSGlGcQ/tsc/k= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=BPvTnVUDt2kn6sTakfYBUjy6fTGY3iiChEwJjn5yMPk=; b=KFhPwYol9dQA1GG1p6+L+1O3A1baC1RnghBHbPp18hM9T8IdLvhu6bZ8s3Zqc+cNAg +hX9FjPQcRlMeNLkLAnEYyJWrJWl+/KuqI/FmKC6YYDDzHVbvSGeZnKFIk/1/AM0RZlo hidKl4/qRxvh6d64TTNmCbO4x1GYXfG+pwPnDOwS5Fs+j9b0TJVBbX4DaHdwVgA+lhVe A9kUs9BCGWtVolBsMqZNO57qUeHXje0Zj72cvVG4Qa/hzOxaGJdebDLOB5FbBFLuiokb daqHk8K4H5GG+lXBER82DVgy+YbjITfnWFgtY9Ix40xu/pj0HKWMCAAkzaVblizl2n+t hGkA== X-Gm-Message-State: AOAM531R9ma5+lW4kF6QJb/u7uL4YRt+fI5N3q+b2l/i1+0FOUhUl6+t nu1YDSnJBx3O89C+adKDYjNeRw== X-Google-Smtp-Source: ABdhPJyi1bO7O6ZJ4EpD/6vHUZ3IyPkOVyCFy1MkYjNh/qLB5Yw7tgN4Y6XDMBR75a27T1ZhkuYPng== X-Received: by 2002:a63:5542:: with SMTP id f2mr4769924pgm.279.1608158553952; Wed, 16 Dec 2020 14:42:33 -0800 (PST) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:42b0:34ff:fe3d:58e6]) by smtp.gmail.com with ESMTPSA id q26sm3561703pfl.219.2020.12.16.14.42.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Dec 2020 14:42:33 -0800 (PST) From: Douglas Anderson To: Mark Brown Cc: msavaliy@qti.qualcomm.com, akashast@codeaurora.org, Stephen Boyd , Roja Rani Yarubandi , Douglas Anderson , Andy Gross , Bjorn Andersson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Subject: [PATCH v2 3/4] spi: spi-geni-qcom: Don't try to set CS if an xfer is pending Date: Wed, 16 Dec 2020 14:41:51 -0800 Message-Id: <20201216144114.v2.3.I07afdedcc49655c5d26880f8df9170aac5792378@changeid> X-Mailer: git-send-email 2.29.2.684.gfbc64c5ab5-goog In-Reply-To: <20201216144114.v2.1.I99ee04f0cb823415df59bd4f550d6ff5756e43d6@changeid> References: <20201216144114.v2.1.I99ee04f0cb823415df59bd4f550d6ff5756e43d6@changeid> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org If we get a timeout sending then this happens: * spi_transfer_wait() will get a timeout. * We'll set the chip select * We'll call handle_err() => handle_fifo_timeout(). Unfortunately that won't work so well on geni. If we got a timeout transferring then it's likely that our interrupt handler is blocked, but we need that same interrupt handler to adjust the chip select. Trying to set the chip select doesn't crash us but ends up confusing our state machine and leads to messages like: Premature done. rx_rem = 32 bpw8 Let's just drop the chip select request in this case. Sure, we might leave the chip select in the wrong state but it's likely it was going to fail anyway and this avoids getting the driver even more confused about what it's doing. The SPI core in general assumes that setting chip select is a simple operation that doesn't fail. Yet another reason to just reconfigure the chip select line as GPIOs. Signed-off-by: Douglas Anderson --- Changes in v2: - ("spi: spi-geni-qcom: Don't try to set CS if an xfer is pending") new for v2. drivers/spi/spi-geni-qcom.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c index d988463e606f..0e4fa52ac017 100644 --- a/drivers/spi/spi-geni-qcom.c +++ b/drivers/spi/spi-geni-qcom.c @@ -204,9 +204,14 @@ static void spi_geni_set_cs(struct spi_device *slv, bool set_flag) goto exit; } - mas->cs_flag = set_flag; - spin_lock_irq(&mas->lock); + if (mas->cur_xfer) { + dev_err(mas->dev, "Can't set CS when prev xfter running\n"); + spin_unlock_irq(&mas->lock); + goto exit; + } + + mas->cs_flag = set_flag; reinit_completion(&mas->cs_done); if (set_flag) geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0);