From patchwork Fri Feb 19 07:43:04 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sascha Hauer X-Patchwork-Id: 8357271 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 712DBC0553 for ; Fri, 19 Feb 2016 07:50:34 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A05A9203B1 for ; Fri, 19 Feb 2016 07:50:33 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 700ED203AD for ; Fri, 19 Feb 2016 07:50:32 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aWfnw-0005aK-3u; Fri, 19 Feb 2016 07:48:44 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aWfjJ-0000Ic-HO for linux-arm-kernel@lists.infradead.org; Fri, 19 Feb 2016 07:43:59 +0000 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.80) (envelope-from ) id 1aWfid-0003Sz-Va; Fri, 19 Feb 2016 08:43:15 +0100 Received: from sha by dude.hi.pengutronix.de with local (Exim 4.86) (envelope-from ) id 1aWfid-0007xS-3S; Fri, 19 Feb 2016 08:43:15 +0100 From: Sascha Hauer To: linux-spi@vger.kernel.org Subject: [PATCH 04/12] spi: imx: drop fallback to PIO Date: Fri, 19 Feb 2016 08:43:04 +0100 Message-Id: <1455867792-26389-5-git-send-email-s.hauer@pengutronix.de> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1455867792-26389-1-git-send-email-s.hauer@pengutronix.de> References: <1455867792-26389-1-git-send-email-s.hauer@pengutronix.de> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160218_234357_958023_E9057622 X-CRM114-Status: GOOD ( 15.86 ) X-Spam-Score: -1.9 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sascha Hauer , Mark Brown , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP At the moment the driver decides to fallback to PIO mode the buffers are already mapped for DMA. It's a bug to access them with the CPU afterwards, so we cannot just fallback to PIO mode. It should not be necessary anyway, since we only use DMA when we verified that it's possible in the fist place, so when prep_slave_sg fails it's a bug, either in the SDMA driver or in the can_dma implementation. Signed-off-by: Sascha Hauer --- drivers/spi/spi-imx.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index b277375..5a48d07 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -945,7 +945,7 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, tx->sgl, tx->nents, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_tx) - goto no_dma; + return -EINVAL; desc_tx->callback = spi_imx_dma_tx_callback; desc_tx->callback_param = (void *)spi_imx; @@ -957,7 +957,7 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, rx->sgl, rx->nents, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_rx) - goto no_dma; + return -EINVAL; desc_rx->callback = spi_imx_dma_rx_callback; desc_rx->callback_param = (void *)spi_imx; @@ -1010,10 +1010,6 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, ret = transfer->len; return ret; - -no_dma: - dev_warn_once(spi_imx->dev, "DMA not available, falling back to PIO\n"); - return -EAGAIN; } static int spi_imx_pio_transfer(struct spi_device *spi, @@ -1040,15 +1036,12 @@ static int spi_imx_pio_transfer(struct spi_device *spi, static int spi_imx_transfer(struct spi_device *spi, struct spi_transfer *transfer) { - int ret; struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master); if (spi_imx->bitbang.master->can_dma && spi_imx_can_dma(spi_imx->bitbang.master, spi, transfer)) { spi_imx->usedma = true; - ret = spi_imx_dma_transfer(spi_imx, transfer); - if (ret != -EAGAIN) - return ret; + return spi_imx_dma_transfer(spi_imx, transfer); } spi_imx->usedma = false;