From patchwork Wed Sep 25 09:11:42 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukasz Majewski X-Patchwork-Id: 11160255 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id EBE2713BD for ; Wed, 25 Sep 2019 09:12:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D3CDF20673 for ; Wed, 25 Sep 2019 09:12:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387963AbfIYJMH (ORCPT ); Wed, 25 Sep 2019 05:12:07 -0400 Received: from mail-out.m-online.net ([212.18.0.10]:34819 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387772AbfIYJMG (ORCPT ); Wed, 25 Sep 2019 05:12:06 -0400 Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 46dXPc51y9z1s1VW; Wed, 25 Sep 2019 11:12:04 +0200 (CEST) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 46dXPc4PXrz1qqkT; Wed, 25 Sep 2019 11:12:04 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id 2EBbxmp59U0j; Wed, 25 Sep 2019 11:12:02 +0200 (CEST) X-Auth-Info: PbuO3twiSHYkDC7a/Or/NRyzLBWFn1JSjsNp6URmSb4= Received: from localhost.localdomain (85-222-111-42.dynamic.chello.pl [85.222.111.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Wed, 25 Sep 2019 11:12:02 +0200 (CEST) From: Lukasz Majewski To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, krzk@kernel.org, Lukasz Majewski Subject: [PATCH v2 1/2] spi: Add call to spi_slave_abort() function when spidev driver is released Date: Wed, 25 Sep 2019 11:11:42 +0200 Message-Id: <20190925091143.15468-2-lukma@denx.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190925091143.15468-1-lukma@denx.de> References: <20190924110547.14770-1-lukma@denx.de> <20190925091143.15468-1-lukma@denx.de> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org This change is necessary for spidev devices (e.g. /dev/spidev3.0) working in the slave mode (like NXP's dspi driver for Vybrid SoC). When SPI HW works in this mode - the master is responsible for providing CS and CLK signals. However, when some fault happens - like for example distortion on SPI lines - the SPI Linux driver needs a chance to recover from this abnormal situation and prepare itself for next (correct) transmission. This change doesn't pose any threat on drivers working in master mode as spi_slave_abort() function checks if SPI slave mode is supported. Signed-off-by: Lukasz Majewski Link: https://lore.kernel.org/r/20190924110547.14770-2-lukma@denx.de Signed-off-by: Mark Brown Reported-by: kbuild test robot --- Changes for v2: - Add #ifdef CONFIG_SPI_SLAVE to not compile in spi_slave_abort() on systems which are only using master mode. (The spi_slave_abort() is 'protected' by this Kconfig define in drivers/spi.c file). This error was spotted by kbuild test robot from Intel. --- drivers/spi/spidev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c index 255786f2e844..3ea9d8a3e6e8 100644 --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -627,6 +627,9 @@ static int spidev_release(struct inode *inode, struct file *filp) if (dofree) kfree(spidev); } +#ifdef CONFIG_SPI_SLAVE + spi_slave_abort(spidev->spi); +#endif mutex_unlock(&device_list_lock); return 0; From patchwork Wed Sep 25 09:11:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukasz Majewski X-Patchwork-Id: 11160253 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4CC9314DB for ; Wed, 25 Sep 2019 09:12:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3519720673 for ; Wed, 25 Sep 2019 09:12:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388162AbfIYJMI (ORCPT ); Wed, 25 Sep 2019 05:12:08 -0400 Received: from mail-out.m-online.net ([212.18.0.9]:47167 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387927AbfIYJMH (ORCPT ); Wed, 25 Sep 2019 05:12:07 -0400 Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 46dXPf4fyyz1rSBb; Wed, 25 Sep 2019 11:12:06 +0200 (CEST) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 46dXPf4DQfz1qqkL; Wed, 25 Sep 2019 11:12:06 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id FXGkXWStI10e; Wed, 25 Sep 2019 11:12:04 +0200 (CEST) X-Auth-Info: o4u4qXuuFLlQh1zBWTsqWbrOIzRBQ+Y0XzcSt5tgRFY= Received: from localhost.localdomain (85-222-111-42.dynamic.chello.pl [85.222.111.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Wed, 25 Sep 2019 11:12:04 +0200 (CEST) From: Lukasz Majewski To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, krzk@kernel.org, Lukasz Majewski Subject: [PATCH v2 2/2] spi: Introduce dspi_slave_abort() function for NXP's dspi SPI driver Date: Wed, 25 Sep 2019 11:11:43 +0200 Message-Id: <20190925091143.15468-3-lukma@denx.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190925091143.15468-1-lukma@denx.de> References: <20190924110547.14770-1-lukma@denx.de> <20190925091143.15468-1-lukma@denx.de> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org This change provides the dspi_slave_abort() function, which is a callback for slave_abort() method of SPI controller generic driver. As in the SPI slave mode the transmission is driven by master, any distortion may cause the slave to enter undefined internal state. To avoid this problem the dspi_slave_abort() terminates all pending and ongoing DMA transactions (with sync) and clears internal FIFOs. Signed-off-by: Lukasz Majewski --- Changes for v2: - None --- drivers/spi/spi-fsl-dspi.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index bec758e978fb..2c0f211eed87 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -1006,6 +1006,25 @@ static void dspi_init(struct fsl_dspi *dspi) SPI_CTARE_FMSZE(0) | SPI_CTARE_DTCP(1)); } +static int dspi_slave_abort(struct spi_master *master) +{ + struct fsl_dspi *dspi = spi_master_get_devdata(master); + + /* + * Terminate all pending DMA transactions for the SPI working + * in SLAVE mode. + */ + dmaengine_terminate_sync(dspi->dma->chan_rx); + dmaengine_terminate_sync(dspi->dma->chan_tx); + + /* Clear the internal DSPI RX and TX FIFO buffers */ + regmap_update_bits(dspi->regmap, SPI_MCR, + SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF, + SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF); + + return 0; +} + static int dspi_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; @@ -1030,6 +1049,7 @@ static int dspi_probe(struct platform_device *pdev) ctlr->dev.of_node = pdev->dev.of_node; ctlr->cleanup = dspi_cleanup; + ctlr->slave_abort = dspi_slave_abort; ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; pdata = dev_get_platdata(&pdev->dev);