From patchwork Wed Jun 28 19:25:12 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 9815203 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 809D760365 for ; Wed, 28 Jun 2017 19:26:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 71D7F1FF1E for ; Wed, 28 Jun 2017 19:26:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 653D1280DE; Wed, 28 Jun 2017 19:26:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 082CD1FF1E for ; Wed, 28 Jun 2017 19:26:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751656AbdF1TZm (ORCPT ); Wed, 28 Jun 2017 15:25:42 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:48260 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751545AbdF1TZ0 (ORCPT ); Wed, 28 Jun 2017 15:25:26 -0400 Received: from [176.12.107.140] (helo=finisterre) by mezzanine.sirena.org.uk with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1dQIaR-0001ZF-Gr; Wed, 28 Jun 2017 19:25:18 +0000 Received: from broonie by finisterre with local (Exim 4.89) (envelope-from ) id 1dQIaO-0004bE-7Y; Wed, 28 Jun 2017 20:25:12 +0100 From: Mark Brown To: Amelie Delaunay Cc: Mark Brown , Mark Brown , Rob Herring , Mark Rutland , Maxime Coquelin , Alexandre Torgue , linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org In-Reply-To: <1498578321-13980-8-git-send-email-amelie.delaunay@st.com> Message-Id: Date: Wed, 28 Jun 2017 20:25:12 +0100 X-SA-Exim-Connect-IP: 176.12.107.140 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Applied "spi: stm32: enhance DMA error management" to the spi tree X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: No (on mezzanine.sirena.org.uk); Unknown failure Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The patch spi: stm32: enhance DMA error management has been applied to the spi tree at git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark From c67ad368cf75d4999d5ef86543d082b4b35dd2d7 Mon Sep 17 00:00:00 2001 From: Amelie Delaunay Date: Tue, 27 Jun 2017 17:45:19 +0200 Subject: [PATCH] spi: stm32: enhance DMA error management This patch reworks DMA error management. In case the DMA callback is called while EOT (End Of Transfer) flag is not set, that means that DMA encountered an error. This error will result in an auto-suspend of SPI flow, which could also result in an overrun. So, in DMA mode, SUSP and OVR flags are a condition to stop the current transfer. Moreover, stm32_spi_can_dma doesn't care about the state of dma channels. During driver probe, master->can_dma is initialised if dma channel request is successful. That's why we must use master->can_dma to know if dma use is possible (dma channel are successfully requested and the transfer size is greater than fifo size). Signed-off-by: Amelie Delaunay Signed-off-by: Mark Brown --- drivers/spi/spi-stm32.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 392c9453c2e6..8a6bff379b21 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -514,6 +514,12 @@ static irqreturn_t stm32_spi_irq(int irq, void *dev_id) dev_warn(spi->dev, "Communication suspended\n"); if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0))) stm32_spi_read_rxfifo(spi, false); + /* + * If communication is suspended while using DMA, it means + * that something went wrong, so stop the current transfer + */ + if (spi->cur_usedma) + end = true; } if (sr & SPI_SR_MODF) { @@ -525,6 +531,12 @@ static irqreturn_t stm32_spi_irq(int irq, void *dev_id) dev_warn(spi->dev, "Overrun: received value discarded\n"); if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0))) stm32_spi_read_rxfifo(spi, false); + /* + * If overrun is detected while using DMA, it means that + * something went wrong, so stop the current transfer + */ + if (spi->cur_usedma) + end = true; } if (sr & SPI_SR_EOT) { @@ -645,12 +657,10 @@ static void stm32_spi_dma_cb(void *data) spin_unlock_irqrestore(&spi->lock, flags); - if (!(sr & SPI_SR_EOT)) { - dev_warn(spi->dev, "DMA callback (sr=0x%08x)\n", sr); + if (!(sr & SPI_SR_EOT)) + dev_warn(spi->dev, "DMA error (sr=0x%08x)\n", sr); - spi_finalize_current_transfer(spi->master); - stm32_spi_disable(spi); - } + /* Now wait for EOT, or SUSP or OVR in case of error */ } /** @@ -986,7 +996,8 @@ static int stm32_spi_transfer_one(struct spi_master *master, spi->tx_len = spi->tx_buf ? transfer->len : 0; spi->rx_len = spi->rx_buf ? transfer->len : 0; - spi->cur_usedma = stm32_spi_can_dma(master, spi_dev, transfer); + spi->cur_usedma = (master->can_dma && + stm32_spi_can_dma(master, spi_dev, transfer)); ret = stm32_spi_transfer_one_setup(spi, spi_dev, transfer); if (ret) {