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=-2.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 DF88CECDFB8 for ; Wed, 18 Jul 2018 09:28:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D1F62075A for ; Wed, 18 Jul 2018 09:28:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="d8nSAKHq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8D1F62075A Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=ti.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730943AbeGRKF2 (ORCPT ); Wed, 18 Jul 2018 06:05:28 -0400 Received: from lelv0142.ext.ti.com ([198.47.23.249]:49038 "EHLO lelv0142.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730112AbeGRKF2 (ORCPT ); Wed, 18 Jul 2018 06:05:28 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id w6I9SPn6070890; Wed, 18 Jul 2018 04:28:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1531906105; bh=9Juan+gsib1qp+5tidK3/xZxUUiyr97+f79NSQmcAkA=; h=From:To:CC:Subject:Date; b=d8nSAKHqYEyUKO3CP8SptKWQ5HwI1A5/JfeZ1DHl2RrKTYdlfg+i00A7KuoS89RFm mV+K6oOSF59kNt/WMh9UwQ+EGlzhi3QELz8S0G6X219Cvvl4lS/nPkjpufd30ddRVh eMzgxtKWbjlknuTaay5HhztmxpfoAej0L79fESuM= Received: from DFLE105.ent.ti.com (dfle105.ent.ti.com [10.64.6.26]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id w6I9SP3F027010; Wed, 18 Jul 2018 04:28:25 -0500 Received: from DFLE110.ent.ti.com (10.64.6.31) by DFLE105.ent.ti.com (10.64.6.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1466.3; Wed, 18 Jul 2018 04:28:24 -0500 Received: from dflp33.itg.ti.com (10.64.6.16) by DFLE110.ent.ti.com (10.64.6.31) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1466.3 via Frontend Transport; Wed, 18 Jul 2018 04:28:24 -0500 Received: from feketebors.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp33.itg.ti.com (8.14.3/8.13.8) with ESMTP id w6I9SMT9027651; Wed, 18 Jul 2018 04:28:23 -0500 From: Peter Ujfalusi To: , CC: , Subject: [PATCH] dmaengine: dma_request_chan_by_mask() to handle deferred probing Date: Wed, 18 Jul 2018 12:29:57 +0300 Message-ID: <20180718092957.1934-1-peter.ujfalusi@ti.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 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 If there are no DMA devices registered yet, return with EPROBE_DEFER similarly to the case when requesting a slave channel. Signed-off-by: Peter Ujfalusi --- drivers/dma/dmaengine.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index d8fc7b58e506..f62e59e1a264 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -768,8 +768,14 @@ struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask) return ERR_PTR(-ENODEV); chan = __dma_request_channel(mask, NULL, NULL); - if (!chan) - chan = ERR_PTR(-ENODEV); + if (!chan) { + mutex_lock(&dma_list_mutex); + if (list_empty(&dma_device_list)) + chan = ERR_PTR(-EPROBE_DEFER); + else + chan = ERR_PTR(-ENODEV); + mutex_unlock(&dma_list_mutex); + } return chan; } -- Peter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki