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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 3CBC9C33C9E for ; Tue, 7 Jan 2020 11:45:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0E0772077B for ; Tue, 7 Jan 2020 11:45:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="XWA0M3sm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727958AbgAGLpO (ORCPT ); Tue, 7 Jan 2020 06:45:14 -0500 Received: from lelv0143.ext.ti.com ([198.47.23.248]:56138 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726690AbgAGLpO (ORCPT ); Tue, 7 Jan 2020 06:45:14 -0500 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id 007Bj55h105265; Tue, 7 Jan 2020 05:45:05 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1578397505; bh=opRM3BxdJrwcWwYPbvHXI+kHoBYD6A8pkYN5zqXedA8=; h=From:To:CC:Subject:Date; b=XWA0M3smZhELM2OjQvdUE1JdjwBZ4QVCtv7vQATPRzSyQ0VbZ6/n40c9wBjLOEram 8m+HfoR9f2iI/AFlp6X2jG0SLk/vRrs/HzQ2Ef7h+HV1nbRkE4ULZRPtLoZxg4THLE +M4e9JOZ1VOe3oRk1C6nyw0g70uFQpKo+RhDAMAs= Received: from DLEE107.ent.ti.com (dlee107.ent.ti.com [157.170.170.37]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 007Bj51m037384 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 7 Jan 2020 05:45:05 -0600 Received: from DLEE108.ent.ti.com (157.170.170.38) by DLEE107.ent.ti.com (157.170.170.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1847.3; Tue, 7 Jan 2020 05:45:04 -0600 Received: from lelv0327.itg.ti.com (10.180.67.183) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1847.3 via Frontend Transport; Tue, 7 Jan 2020 05:45:04 -0600 Received: from feketebors.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 007Bj1Zv073150; Tue, 7 Jan 2020 05:45:02 -0600 From: Peter Ujfalusi To: , , , CC: , , , , Subject: [PATCH v2] iio: adc: stm32-dfsdm: Use dma_request_chan() instead dma_request_slave_channel() Date: Tue, 7 Jan 2020 13:45:32 +0200 Message-ID: <20200107114532.6697-1-peter.ujfalusi@ti.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma_request_slave_channel() is a wrapper on top of dma_request_chan() eating up the error code. By using dma_request_chan() directly the driver can support deferred probing against DMA. Signed-off-by: Peter Ujfalusi --- Hi, Changes since v1: - Fall back to IRQ mode for ADC only in case of ENODEV Regards, Peter drivers/iio/adc/stm32-dfsdm-adc.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index e493242c266e..74a2211bdff4 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -1383,9 +1383,13 @@ static int stm32_dfsdm_dma_request(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); - adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); - if (!adc->dma_chan) - return -EINVAL; + adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx"); + if (IS_ERR(adc->dma_chan)) { + int ret = PTR_ERR(adc->dma_chan); + + adc->dma_chan = NULL; + return ret; + } adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE, @@ -1509,7 +1513,16 @@ static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev) init_completion(&adc->completion); /* Optionally request DMA */ - if (stm32_dfsdm_dma_request(indio_dev)) { + ret = stm32_dfsdm_dma_request(indio_dev); + if (ret) { + if (ret != -ENODEV) { + if (ret != -EPROBE_DEFER) + dev_err(&indio_dev->dev, + "DMA channel request failed with %d\n", + ret); + return ret; + } + dev_dbg(&indio_dev->dev, "No DMA support\n"); return 0; } -- Peter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki