From patchwork Fri Sep 6 14:18:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Ujfalusi X-Patchwork-Id: 11135359 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 D6EDA112B for ; Fri, 6 Sep 2019 14:18:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B710D214E0 for ; Fri, 6 Sep 2019 14:18:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="iK2R5BfL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394362AbfIFOR6 (ORCPT ); Fri, 6 Sep 2019 10:17:58 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:60278 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394290AbfIFOR5 (ORCPT ); Fri, 6 Sep 2019 10:17:57 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id x86EHs8R033208; Fri, 6 Sep 2019 09:17:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1567779474; bh=Q0YSzmtvj7sqG004BV4lez3XreU1ptGoRlCRKi0kkXE=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=iK2R5BfLmLoYQap6f051TME+qiH2qqg6MAM9FFHgfLpiiMrKzF1qqgB5KaVZrpLbf vm81b+vTVeokvamwL1wAiQWWgdZP5WxrwDGxT2z1y1J5iHD2VBIH0Qz3J286oDDRW2 zDMT/O3VG5LwVPZl9Y+hpoqsfO7k0Uvxqrc0OsZo= Received: from DFLE100.ent.ti.com (dfle100.ent.ti.com [10.64.6.21]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x86EHsY8065345 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 6 Sep 2019 09:17:54 -0500 Received: from DFLE101.ent.ti.com (10.64.6.22) by DFLE100.ent.ti.com (10.64.6.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Fri, 6 Sep 2019 09:17:54 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DFLE101.ent.ti.com (10.64.6.22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Fri, 6 Sep 2019 09:17:54 -0500 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 x86EHlOf032723; Fri, 6 Sep 2019 09:17:52 -0500 From: Peter Ujfalusi To: , CC: , , , Subject: [RFC 2/3] dmaengine: of_dma: Function to look up the DMA domain of a client Date: Fri, 6 Sep 2019 17:18:15 +0300 Message-ID: <20190906141816.24095-3-peter.ujfalusi@ti.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190906141816.24095-1-peter.ujfalusi@ti.com> References: <20190906141816.24095-1-peter.ujfalusi@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Find the DMA domain controller of the client device by iterating up in device tree looking for the closest 'dma-domain-controller' property. If the client's node is not provided then check the DT root for the controller. Signed-off-by: Peter Ujfalusi --- drivers/dma/of-dma.c | 42 ++++++++++++++++++++++++++++++++++++++++++ include/linux/of_dma.h | 7 +++++++ 2 files changed, 49 insertions(+) diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c index c2d779daa4b5..04b5795cd76b 100644 --- a/drivers/dma/of-dma.c +++ b/drivers/dma/of-dma.c @@ -18,6 +18,48 @@ static LIST_HEAD(of_dma_list); static DEFINE_MUTEX(of_dma_lock); +/** + * of_find_dma_domain - Get the domain DMA controller + * @np: device node of the client device + * + * Look up the DMA controller of the domain the client device is part of. + * Finds the dma-domain controller the client device belongs to. It is used when + * requesting non slave channels (like channel for memcpy) to make sure that the + * channel can be request from a DMA controller which can service the given + * domain best. + * + * Returns the device_node pointer of the DMA controller or succes or NULL on + * error. + */ +struct device_node *of_find_dma_domain(struct device_node *np) +{ + struct device_node *dma_domain = NULL; + phandle dma_phandle; + + /* + * If no device_node is provided look at the root level for system + * default DMA controller for modules. + */ + if (!np) + np = of_root; + + if (!np || !of_node_get(np)) + return NULL; + + do { + if (of_property_read_u32(np, "dma-domain-controller", + &dma_phandle)) + np = of_get_next_parent(np); + else { + dma_domain = of_find_node_by_phandle(dma_phandle); + of_node_put(np); + } + } while (!dma_domain && np); + + return dma_domain; +} +EXPORT_SYMBOL_GPL(of_find_dma_domain); + /** * of_dma_find_controller - Get a DMA controller in DT DMA helpers list * @dma_spec: pointer to DMA specifier as found in the device tree diff --git a/include/linux/of_dma.h b/include/linux/of_dma.h index fd706cdf255c..6eab0a8d3335 100644 --- a/include/linux/of_dma.h +++ b/include/linux/of_dma.h @@ -32,6 +32,8 @@ struct of_dma_filter_info { }; #ifdef CONFIG_DMA_OF +extern struct device_node *of_find_dma_domain(struct device_node *np); + extern int of_dma_controller_register(struct device_node *np, struct dma_chan *(*of_dma_xlate) (struct of_phandle_args *, struct of_dma *), @@ -52,6 +54,11 @@ extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec struct of_dma *ofdma); #else +static inline struct device_node *of_find_dma_domain(struct device_node *np) +{ + return NULL; +} + static inline int of_dma_controller_register(struct device_node *np, struct dma_chan *(*of_dma_xlate) (struct of_phandle_args *, struct of_dma *),