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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 A80E5C28CBC for ; Thu, 30 Apr 2020 14:01:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86572206D9 for ; Thu, 30 Apr 2020 14:01:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588255264; bh=Mb6CEoGitb2lEIgQ7hVXRgTVv0vpAHGZF1/Z+OeSdqs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YlpPk41MchlVDjzhPsnFhaTen0627UK78HCVJn5iuLPMGyepLazdoo11ay+6GGHsk 21Bdm9ZQS/ILkSQ1uUlzjGrcz+HpKnWvKEIBLmleByYVaqNjrSxB/JmSM4c4LUS4qk TNJ/ktCiaMlwqzcIIQSRjGhdIaWxGdwDwM0qegFg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728313AbgD3OBD (ORCPT ); Thu, 30 Apr 2020 10:01:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:36162 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728886AbgD3NyG (ORCPT ); Thu, 30 Apr 2020 09:54:06 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 53A582072A; Thu, 30 Apr 2020 13:54:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588254845; bh=Mb6CEoGitb2lEIgQ7hVXRgTVv0vpAHGZF1/Z+OeSdqs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E0uDLeQ8wKoW5QOLA1kOxOgBQDn/fG6uI4jqRnZ7GEkvwPBGrcg1NzTaZPX5jAyA0 udKq9SBaKjErzCb7lqxEzeZL2/QEDJUaglqWFZYCE/adcJWX6b9Ce0hwYPMOVmkUb3 kUikAkpwpM1zjhEuu3fW66D7xV0hOX2PanjJX8UI= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Olivier Moysan , Fabrice Gasnier , Stable@vger.kernel.org, Jonathan Cameron , Sasha Levin , linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 4.14 02/27] iio: adc: stm32-adc: fix sleep in atomic context Date: Thu, 30 Apr 2020 09:53:37 -0400 Message-Id: <20200430135402.20994-2-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200430135402.20994-1-sashal@kernel.org> References: <20200430135402.20994-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org From: Olivier Moysan [ Upstream commit e2042d2936dfc84e9c600fe9b9d0039ca0e54b7d ] This commit fixes the following error: "BUG: sleeping function called from invalid context at kernel/irq/chip.c" In DMA mode suppress the trigger irq handler, and make the buffer transfers directly in DMA callback, instead. Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support") Signed-off-by: Olivier Moysan Acked-by: Fabrice Gasnier Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/adc/stm32-adc.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 258a4712167a2..3cfb2d4b24412 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -1311,8 +1311,30 @@ static unsigned int stm32_adc_dma_residue(struct stm32_adc *adc) static void stm32_adc_dma_buffer_done(void *data) { struct iio_dev *indio_dev = data; + struct stm32_adc *adc = iio_priv(indio_dev); + int residue = stm32_adc_dma_residue(adc); + + /* + * In DMA mode the trigger services of IIO are not used + * (e.g. no call to iio_trigger_poll). + * Calling irq handler associated to the hardware trigger is not + * relevant as the conversions have already been done. Data + * transfers are performed directly in DMA callback instead. + * This implementation avoids to call trigger irq handler that + * may sleep, in an atomic context (DMA irq handler context). + */ + dev_dbg(&indio_dev->dev, "%s bufi=%d\n", __func__, adc->bufi); - iio_trigger_poll_chained(indio_dev->trig); + while (residue >= indio_dev->scan_bytes) { + u16 *buffer = (u16 *)&adc->rx_buf[adc->bufi]; + + iio_push_to_buffers(indio_dev, buffer); + + residue -= indio_dev->scan_bytes; + adc->bufi += indio_dev->scan_bytes; + if (adc->bufi >= adc->rx_buf_sz) + adc->bufi = 0; + } } static int stm32_adc_dma_start(struct iio_dev *indio_dev) @@ -1648,6 +1670,7 @@ static int stm32_adc_probe(struct platform_device *pdev) { struct iio_dev *indio_dev; struct device *dev = &pdev->dev; + irqreturn_t (*handler)(int irq, void *p) = NULL; struct stm32_adc *adc; int ret; @@ -1730,9 +1753,11 @@ static int stm32_adc_probe(struct platform_device *pdev) if (ret < 0) goto err_clk_disable; + if (!adc->dma_chan) + handler = &stm32_adc_trigger_handler; + ret = iio_triggered_buffer_setup(indio_dev, - &iio_pollfunc_store_time, - &stm32_adc_trigger_handler, + &iio_pollfunc_store_time, handler, &stm32_adc_buffer_setup_ops); if (ret) { dev_err(&pdev->dev, "buffer setup failed\n"); -- 2.20.1