From patchwork Sat Aug 10 16:52:19 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Mack X-Patchwork-Id: 2842489 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 9BFE99F271 for ; Sat, 10 Aug 2013 17:25:13 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B5C0F201BB for ; Sat, 10 Aug 2013 17:25:12 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B950F2015E for ; Sat, 10 Aug 2013 17:25:11 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V8CRb-0004HH-HF; Sat, 10 Aug 2013 16:55:12 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V8CQn-00008h-Tt; Sat, 10 Aug 2013 16:54:21 +0000 Received: from svenfoo.org ([82.94.215.22] helo=mail.zonque.de) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V8CPn-0008SM-5r for linux-arm-kernel@lists.infradead.org; Sat, 10 Aug 2013 16:53:27 +0000 Received: from localhost (localhost [127.0.0.1]) by mail.zonque.de (Postfix) with ESMTP id C01D5C08E9; Sat, 10 Aug 2013 18:52:35 +0200 (CEST) Received: from mail.zonque.de ([127.0.0.1]) by localhost (rambrand.bugwerft.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id W_DeBwXxFrQp; Sat, 10 Aug 2013 18:52:35 +0200 (CEST) Received: from tamtam.fritz.box (p5DDC5C11.dip0.t-ipconnect.de [93.220.92.17]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.zonque.de (Postfix) with ESMTPSA id 000D5C08E3; Sat, 10 Aug 2013 18:52:34 +0200 (CEST) From: Daniel Mack To: vinod.koul@intel.com, djbw@fb.com Subject: [PATCH v2 05/11] dma: mmp_pdma: make the controller a DMA provider Date: Sat, 10 Aug 2013 18:52:19 +0200 Message-Id: <1376153545-14361-6-git-send-email-zonque@gmail.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1376153545-14361-1-git-send-email-zonque@gmail.com> References: <1376153545-14361-1-git-send-email-zonque@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130810_125319_844594_9DB585B5 X-CRM114-Status: GOOD ( 15.32 ) X-Spam-Score: 1.6 (+) Cc: wangx@marvell.com, eric.y.miao@gmail.com, arnd@arndb.de, nico@fluxnic.net, haojian.zhuang@gmail.com, Daniel Mack , cxie4@marvell.com, ezequiel.garcia@free-electrons.com, linux@arm.linux.org.uk, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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=-2.4 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, FREEMAIL_FROM,KHOP_BIG_TO_CC,RCVD_IN_DNSWL_MED,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham 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 This patch makes the mmp_pdma controller able to provide DMA resources in DT environments by providing an dma xlate function. of_dma_simple_xlate() isn't used here, because if fails to handle multiple different DMA engines or several instances of the same controller. Instead, a private implementation is provided that makes use of the newly introduced dma_get_slave_channel() call. Signed-off-by: Daniel Mack --- drivers/dma/mmp_pdma.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c index 9dda27e..0ec5c21 100644 --- a/drivers/dma/mmp_pdma.c +++ b/drivers/dma/mmp_pdma.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -784,6 +785,39 @@ static struct of_device_id mmp_pdma_dt_ids[] = { }; MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids); +static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct mmp_pdma_device *d = ofdma->of_dma_data; + struct dma_chan *chan, *candidate; + +retry: + candidate = NULL; + + /* walk the list of channels registered with the current instance and + * find one that is currently unused */ + list_for_each_entry(chan, &d->device.channels, device_node) + if (chan->client_count == 0) { + candidate = chan; + break; + } + + if (!candidate) + return NULL; + + /* dma_get_slave_channel will return NULL if we lost a race between + * the lookup and the reservation */ + chan = dma_get_slave_channel(candidate); + + if (chan) { + struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan); + c->drcmr = dma_spec->args[0]; + return chan; + } + + goto retry; +} + static int mmp_pdma_probe(struct platform_device *op) { struct mmp_pdma_device *pdev; @@ -870,6 +904,16 @@ static int mmp_pdma_probe(struct platform_device *op) return ret; } + if (op->dev.of_node) { + /* Device-tree DMA controller registration */ + ret = of_dma_controller_register(op->dev.of_node, + mmp_pdma_dma_xlate, pdev); + if (ret < 0) { + dev_err(&op->dev, "of_dma_controller_register failed\n"); + return ret; + } + } + dev_info(pdev->device.dev, "initialized\n"); return 0; }