From patchwork Thu Oct 11 16:41:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 10637009 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 19F4F1508 for ; Thu, 11 Oct 2018 16:45:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F14222BC30 for ; Thu, 11 Oct 2018 16:45:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E18272BC33; Thu, 11 Oct 2018 16:45:01 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id F374C2BC30 for ; Thu, 11 Oct 2018 16:45:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=aBv8c9XB5APLPkURgOjMmuDLy9d0ySua+FgDwG7XIts=; b=lofLs6mrCsXHP20ARY/oQx9GZa PSpa+IBKGADDOiYFTXarBcyrFH6oVxfNzqOQOxS+E4X1zIiXeexf0NEhNM4i03283RW+tdCPa5hJW 9QtiMoImN+oHp5wWKcyy/Hcp5jKAh7jFK0Uj4gKs4ITXKgs6zWgjv5+LANPNFQ7qBll54EnKWum4m GiQcQASfQ5ck1zgUOtdQ06zXJ25xmSr297MIWw3fQ4O8HKyt5Qh6dHDDE3uatqN8TeRqd/V+I1KCw JE7/1zF7axd3mJW5fQ+BRcTM55KDQ+YhKycK1MEGTxSQVUpzolfWxkr1EUVi13Uq+ibvdUD3IfUKK J3Ubee0A==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gAe52-0007NS-T3; Thu, 11 Oct 2018 16:44:57 +0000 Received: from conuserg-07.nifty.com ([210.131.2.74]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gAe27-00063M-7b for linux-arm-kernel@lists.infradead.org; Thu, 11 Oct 2018 16:42:34 +0000 Received: from grover.tkatk1.zaq.ne.jp (zaqdadce369.zaq.ne.jp [218.220.227.105]) (authenticated) by conuserg-07.nifty.com with ESMTP id w9BGf9bA007909; Fri, 12 Oct 2018 01:41:12 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-07.nifty.com w9BGf9bA007909 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1539276072; bh=nuh+v8r6xOBP8NZgToHTB89YpD1cHdrRs60TJBD5hhg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eZANGEfpZL2I/zyw9xbp8vEmmFG8L2vrXgILEcIPsiNR1agSFsRvg6Pf5Tw84Qkrn BJCkkEiGRi7CBNmkMy6xkDyRCxZTASaI04poL/BGFuzXymdK00XG54ufHgJ9L7jWcU lau/URSHB+Kswl/VmQEgHc55uis8qwI8rovbJLR1valo3wdmx16YM7v9arQ/oJmJ+1 X8xs9k077SmQlFbsxYqhiDbUD/1686Y6AjXKQ21VyvNywzjEam+bYly8ir4hfE7Hwb dV82rSN/r4LneTtcpG9W7JmvnsK2onCIRbNrTKiAiJpIOTmM7ovMAar2g/3FJAaIRD eMF8G2lfozqmw== X-Nifty-SrcIP: [218.220.227.105] From: Masahiro Yamada To: Vinod Koul , dmaengine@vger.kernel.org Subject: [PATCH v4 2/2] dmaengine: uniphier-mdmac: add UniPhier MIO DMAC driver Date: Fri, 12 Oct 2018 01:41:03 +0900 Message-Id: <1539276063-5103-3-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1539276063-5103-1-git-send-email-yamada.masahiro@socionext.com> References: <1539276063-5103-1-git-send-email-yamada.masahiro@socionext.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181011_094155_567131_58847503 X-CRM114-Status: GOOD ( 23.80 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Masahiro Yamada , linux-kernel@vger.kernel.org, Jassi Brar , Masami Hiramatsu , Dan Williams , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The MIO DMAC (Media IO DMA Controller) is used in UniPhier LD4, Pro4, and sLD8 SoCs. Signed-off-by: Masahiro Yamada --- Changes in v4: - Use C style comments instead of C++ ones - Move long return types to the previous line - Remove distracting double-underscore prefixing - Fix a double-spacing between sentences - Remove the empty ->device_config hook - Fix residue calculation - Fix ->{src,dst}_addr_widths - Add ->device_free_chan_resources() hook - Make sure to stop the hardware in .remove hook and avoid memory leak Changes in v3: - Get residue from on-flight chunk - Use GFP_NOWAIT instead of GFP_KERNEL in prep_slave_sg - Use device_config hook - Add NULL pointer check for txstate Changes in v2: - Use platform_irq_count() to get the number of channels MAINTAINERS | 1 + drivers/dma/Kconfig | 11 + drivers/dma/Makefile | 1 + drivers/dma/uniphier-mdmac.c | 506 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 519 insertions(+) create mode 100644 drivers/dma/uniphier-mdmac.c diff --git a/MAINTAINERS b/MAINTAINERS index e38ba7e..847fa12 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2192,6 +2192,7 @@ F: arch/arm/mm/cache-uniphier.c F: arch/arm64/boot/dts/socionext/uniphier* F: drivers/bus/uniphier-system-bus.c F: drivers/clk/uniphier/ +F: drivers/dmaengine/uniphier-mdmac.c F: drivers/gpio/gpio-uniphier.c F: drivers/i2c/busses/i2c-uniphier* F: drivers/irqchip/irq-uniphier-aidet.c diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index dacf3f4..8b8c7f0 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -576,6 +576,17 @@ config TIMB_DMA help Enable support for the Timberdale FPGA DMA engine. +config UNIPHIER_MDMAC + tristate "UniPhier MIO DMAC" + depends on ARCH_UNIPHIER || COMPILE_TEST + depends on OF + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + Enable support for the MIO DMAC (Media I/O DMA controller) on the + UniPhier platform. This DMA controller is used as the external + DMA engine of the SD/eMMC controllers of the LD4, Pro4, sLD8 SoCs. + config XGENE_DMA tristate "APM X-Gene DMA support" depends on ARCH_XGENE || COMPILE_TEST diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index c91702d..973a170 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -69,6 +69,7 @@ obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o obj-$(CONFIG_TEGRA210_ADMA) += tegra210-adma.o obj-$(CONFIG_TIMB_DMA) += timb_dma.o +obj-$(CONFIG_UNIPHIER_MDMAC) += uniphier-mdmac.o obj-$(CONFIG_XGENE_DMA) += xgene-dma.o obj-$(CONFIG_ZX_DMA) += zx_dma.o obj-$(CONFIG_ST_FDMA) += st_fdma.o diff --git a/drivers/dma/uniphier-mdmac.c b/drivers/dma/uniphier-mdmac.c new file mode 100644 index 0000000..ec65a7430 --- /dev/null +++ b/drivers/dma/uniphier-mdmac.c @@ -0,0 +1,506 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (C) 2018 Socionext Inc. +// Author: Masahiro Yamada + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "virt-dma.h" + +/* registers common for all channels */ +#define UNIPHIER_MDMAC_CMD 0x000 /* issue DMA start/abort */ +#define UNIPHIER_MDMAC_CMD_ABORT BIT(31) /* 1: abort, 0: start */ + +/* per-channel registers */ +#define UNIPHIER_MDMAC_CH_OFFSET 0x100 +#define UNIPHIER_MDMAC_CH_STRIDE 0x040 + +#define UNIPHIER_MDMAC_CH_IRQ_STAT 0x010 /* current hw status (RO) */ +#define UNIPHIER_MDMAC_CH_IRQ_REQ 0x014 /* latched STAT (WOC) */ +#define UNIPHIER_MDMAC_CH_IRQ_EN 0x018 /* IRQ enable mask */ +#define UNIPHIER_MDMAC_CH_IRQ_DET 0x01c /* REQ & EN (RO) */ +#define UNIPHIER_MDMAC_CH_IRQ__ABORT BIT(13) +#define UNIPHIER_MDMAC_CH_IRQ__DONE BIT(1) +#define UNIPHIER_MDMAC_CH_SRC_MODE 0x020 /* mode of source */ +#define UNIPHIER_MDMAC_CH_DEST_MODE 0x024 /* mode of destination */ +#define UNIPHIER_MDMAC_CH_MODE__ADDR_INC (0 << 4) +#define UNIPHIER_MDMAC_CH_MODE__ADDR_DEC (1 << 4) +#define UNIPHIER_MDMAC_CH_MODE__ADDR_FIXED (2 << 4) +#define UNIPHIER_MDMAC_CH_SRC_ADDR 0x028 /* source address */ +#define UNIPHIER_MDMAC_CH_DEST_ADDR 0x02c /* destination address */ +#define UNIPHIER_MDMAC_CH_SIZE 0x030 /* transfer bytes */ + +#define UNIPHIER_MDMAC_SLAVE_BUSWIDTHS \ + (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) + +struct uniphier_mdmac_desc { + struct virt_dma_desc vd; + struct scatterlist *sgl; + unsigned int sg_len; + unsigned int sg_cur; + enum dma_transfer_direction dir; +}; + +struct uniphier_mdmac_chan { + struct virt_dma_chan vc; + struct uniphier_mdmac_device *mdev; + struct uniphier_mdmac_desc *md; + void __iomem *reg_ch_base; + unsigned int chan_id; +}; + +struct uniphier_mdmac_device { + struct dma_device ddev; + struct clk *clk; + void __iomem *reg_base; + struct uniphier_mdmac_chan channels[0]; +}; + +static struct uniphier_mdmac_chan * +to_uniphier_mdmac_chan(struct virt_dma_chan *vc) +{ + return container_of(vc, struct uniphier_mdmac_chan, vc); +} + +static struct uniphier_mdmac_desc * +to_uniphier_mdmac_desc(struct virt_dma_desc *vd) +{ + return container_of(vd, struct uniphier_mdmac_desc, vd); +} + +/* mc->vc.lock must be held by caller */ +static struct uniphier_mdmac_desc * +uniphier_mdmac_next_desc(struct uniphier_mdmac_chan *mc) +{ + struct virt_dma_desc *vd; + + vd = vchan_next_desc(&mc->vc); + if (!vd) { + mc->md = NULL; + return NULL; + } + + list_del(&vd->node); + + mc->md = to_uniphier_mdmac_desc(vd); + + return mc->md; +} + +/* mc->vc.lock must be held by caller */ +static void uniphier_mdmac_handle(struct uniphier_mdmac_chan *mc, + struct uniphier_mdmac_desc *md) +{ + struct uniphier_mdmac_device *mdev = mc->mdev; + struct scatterlist *sg; + u32 irq_flag = UNIPHIER_MDMAC_CH_IRQ__DONE; + u32 src_mode, src_addr, dest_mode, dest_addr, chunk_size; + + sg = &md->sgl[md->sg_cur]; + + if (md->dir == DMA_MEM_TO_DEV) { + src_mode = UNIPHIER_MDMAC_CH_MODE__ADDR_INC; + src_addr = sg_dma_address(sg); + dest_mode = UNIPHIER_MDMAC_CH_MODE__ADDR_FIXED; + dest_addr = 0; + } else { + src_mode = UNIPHIER_MDMAC_CH_MODE__ADDR_FIXED; + src_addr = 0; + dest_mode = UNIPHIER_MDMAC_CH_MODE__ADDR_INC; + dest_addr = sg_dma_address(sg); + } + + chunk_size = sg_dma_len(sg); + + writel(src_mode, mc->reg_ch_base + UNIPHIER_MDMAC_CH_SRC_MODE); + writel(dest_mode, mc->reg_ch_base + UNIPHIER_MDMAC_CH_DEST_MODE); + writel(src_addr, mc->reg_ch_base + UNIPHIER_MDMAC_CH_SRC_ADDR); + writel(dest_addr, mc->reg_ch_base + UNIPHIER_MDMAC_CH_DEST_ADDR); + writel(chunk_size, mc->reg_ch_base + UNIPHIER_MDMAC_CH_SIZE); + + /* write 1 to clear */ + writel(irq_flag, mc->reg_ch_base + UNIPHIER_MDMAC_CH_IRQ_REQ); + + writel(irq_flag, mc->reg_ch_base + UNIPHIER_MDMAC_CH_IRQ_EN); + + writel(BIT(mc->chan_id), mdev->reg_base + UNIPHIER_MDMAC_CMD); +} + +/* mc->vc.lock must be held by caller */ +static void uniphier_mdmac_start(struct uniphier_mdmac_chan *mc) +{ + struct uniphier_mdmac_desc *md; + + md = uniphier_mdmac_next_desc(mc); + if (md) + uniphier_mdmac_handle(mc, md); +} + +/* mc->vc.lock must be held by caller */ +static int uniphier_mdmac_abort(struct uniphier_mdmac_chan *mc) +{ + struct uniphier_mdmac_device *mdev = mc->mdev; + u32 irq_flag = UNIPHIER_MDMAC_CH_IRQ__ABORT; + u32 val; + + /* write 1 to clear */ + writel(irq_flag, mc->reg_ch_base + UNIPHIER_MDMAC_CH_IRQ_REQ); + + writel(UNIPHIER_MDMAC_CMD_ABORT | BIT(mc->chan_id), + mdev->reg_base + UNIPHIER_MDMAC_CMD); + + /* + * Abort should be accepted soon. We poll the bit here instead of + * waiting for the interrupt. + */ + return readl_poll_timeout(mc->reg_ch_base + UNIPHIER_MDMAC_CH_IRQ_REQ, + val, val & irq_flag, 0, 20); +} + +static irqreturn_t uniphier_mdmac_interrupt(int irq, void *dev_id) +{ + struct uniphier_mdmac_chan *mc = dev_id; + struct uniphier_mdmac_desc *md; + irqreturn_t ret = IRQ_HANDLED; + u32 irq_stat; + + spin_lock(&mc->vc.lock); + + irq_stat = readl(mc->reg_ch_base + UNIPHIER_MDMAC_CH_IRQ_DET); + + /* + * Some channels share a single interrupt line. If the IRQ status is 0, + * this is probably triggered by a different channel. + */ + if (!irq_stat) { + ret = IRQ_NONE; + goto out; + } + + /* write 1 to clear */ + writel(irq_stat, mc->reg_ch_base + UNIPHIER_MDMAC_CH_IRQ_REQ); + + /* + * UNIPHIER_MDMAC_CH_IRQ__DONE interrupt is asserted even when the DMA + * is aborted. To distinguish the normal completion and the abort, + * check mc->md. If it is NULL, we are aborting. + */ + md = mc->md; + if (!md) + goto out; + + md->sg_cur++; + + if (md->sg_cur >= md->sg_len) { + vchan_cookie_complete(&md->vd); + md = uniphier_mdmac_next_desc(mc); + if (!md) + goto out; + } + + uniphier_mdmac_handle(mc, md); + +out: + spin_unlock(&mc->vc.lock); + + return ret; +} + +static void uniphier_mdmac_free_chan_resources(struct dma_chan *chan) +{ + vchan_free_chan_resources(to_virt_chan(chan)); +} + +static struct dma_async_tx_descriptor * +uniphier_mdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, + unsigned int sg_len, + enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct uniphier_mdmac_desc *md; + + if (!is_slave_direction(direction)) + return NULL; + + md = kzalloc(sizeof(*md), GFP_NOWAIT); + if (!md) + return NULL; + + md->sgl = sgl; + md->sg_len = sg_len; + md->dir = direction; + + return vchan_tx_prep(vc, &md->vd, flags); +} + +static int uniphier_mdmac_terminate_all(struct dma_chan *chan) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct uniphier_mdmac_chan *mc = to_uniphier_mdmac_chan(vc); + unsigned long flags; + int ret = 0; + LIST_HEAD(head); + + spin_lock_irqsave(&vc->lock, flags); + + if (mc->md) { + vchan_terminate_vdesc(&mc->md->vd); + mc->md = NULL; + ret = uniphier_mdmac_abort(mc); + } + vchan_get_all_descriptors(vc, &head); + + spin_unlock_irqrestore(&vc->lock, flags); + + vchan_dma_desc_free_list(vc, &head); + + return ret; +} + +static void uniphier_mdmac_synchronize(struct dma_chan *chan) +{ + vchan_synchronize(to_virt_chan(chan)); +} + +static enum dma_status uniphier_mdmac_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct virt_dma_chan *vc; + struct virt_dma_desc *vd; + struct uniphier_mdmac_chan *mc; + struct uniphier_mdmac_desc *md = NULL; + enum dma_status stat; + unsigned long flags; + int i; + + stat = dma_cookie_status(chan, cookie, txstate); + /* Return immediately if we do not need to compute the residue. */ + if (stat == DMA_COMPLETE || !txstate) + return stat; + + vc = to_virt_chan(chan); + + spin_lock_irqsave(&vc->lock, flags); + + mc = to_uniphier_mdmac_chan(vc); + + if (mc->md && mc->md->vd.tx.cookie == cookie) { + /* residue from the on-flight chunk */ + txstate->residue = readl(mc->reg_ch_base + + UNIPHIER_MDMAC_CH_SIZE); + md = mc->md; + } + + if (!md) { + vd = vchan_find_desc(vc, cookie); + if (vd) + md = to_uniphier_mdmac_desc(vd); + } + + if (md) { + /* residue from the queued chunks */ + for (i = md->sg_cur; i < md->sg_len; i++) + txstate->residue += sg_dma_len(&md->sgl[i]); + } + + spin_unlock_irqrestore(&vc->lock, flags); + + return stat; +} + +static void uniphier_mdmac_issue_pending(struct dma_chan *chan) +{ + struct virt_dma_chan *vc = to_virt_chan(chan); + struct uniphier_mdmac_chan *mc = to_uniphier_mdmac_chan(vc); + unsigned long flags; + + spin_lock_irqsave(&vc->lock, flags); + + if (vchan_issue_pending(vc) && !mc->md) + uniphier_mdmac_start(mc); + + spin_unlock_irqrestore(&vc->lock, flags); +} + +static void uniphier_mdmac_desc_free(struct virt_dma_desc *vd) +{ + kfree(to_uniphier_mdmac_desc(vd)); +} + +static int uniphier_mdmac_chan_init(struct platform_device *pdev, + struct uniphier_mdmac_device *mdev, + int chan_id) +{ + struct device *dev = &pdev->dev; + struct uniphier_mdmac_chan *mc = &mdev->channels[chan_id]; + char *irq_name; + int irq, ret; + + irq = platform_get_irq(pdev, chan_id); + if (irq < 0) { + dev_err(&pdev->dev, "failed to get IRQ number for ch%d\n", + chan_id); + return irq; + } + + irq_name = devm_kasprintf(dev, GFP_KERNEL, "uniphier-mio-dmac-ch%d", + chan_id); + if (!irq_name) + return -ENOMEM; + + ret = devm_request_irq(dev, irq, uniphier_mdmac_interrupt, + IRQF_SHARED, irq_name, mc); + if (ret) + return ret; + + mc->mdev = mdev; + mc->reg_ch_base = mdev->reg_base + UNIPHIER_MDMAC_CH_OFFSET + + UNIPHIER_MDMAC_CH_STRIDE * chan_id; + mc->chan_id = chan_id; + mc->vc.desc_free = uniphier_mdmac_desc_free; + vchan_init(&mc->vc, &mdev->ddev); + + return 0; +} + +static int uniphier_mdmac_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct uniphier_mdmac_device *mdev; + struct dma_device *ddev; + struct resource *res; + int nr_chans, ret, i; + + nr_chans = platform_irq_count(pdev); + if (nr_chans < 0) + return nr_chans; + + ret = dma_set_mask(dev, DMA_BIT_MASK(32)); + if (ret) + return ret; + + mdev = devm_kzalloc(dev, struct_size(mdev, channels, nr_chans), + GFP_KERNEL); + if (!mdev) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mdev->reg_base = devm_ioremap_resource(dev, res); + if (IS_ERR(mdev->reg_base)) + return PTR_ERR(mdev->reg_base); + + mdev->clk = devm_clk_get(dev, NULL); + if (IS_ERR(mdev->clk)) { + dev_err(dev, "failed to get clock\n"); + return PTR_ERR(mdev->clk); + } + + ret = clk_prepare_enable(mdev->clk); + if (ret) + return ret; + + ddev = &mdev->ddev; + ddev->dev = dev; + dma_cap_set(DMA_PRIVATE, ddev->cap_mask); + ddev->src_addr_widths = UNIPHIER_MDMAC_SLAVE_BUSWIDTHS; + ddev->dst_addr_widths = UNIPHIER_MDMAC_SLAVE_BUSWIDTHS; + ddev->directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM); + ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; + ddev->device_free_chan_resources = uniphier_mdmac_free_chan_resources; + ddev->device_prep_slave_sg = uniphier_mdmac_prep_slave_sg; + ddev->device_terminate_all = uniphier_mdmac_terminate_all; + ddev->device_synchronize = uniphier_mdmac_synchronize; + ddev->device_tx_status = uniphier_mdmac_tx_status; + ddev->device_issue_pending = uniphier_mdmac_issue_pending; + INIT_LIST_HEAD(&ddev->channels); + + for (i = 0; i < nr_chans; i++) { + ret = uniphier_mdmac_chan_init(pdev, mdev, i); + if (ret) + goto disable_clk; + } + + ret = dma_async_device_register(ddev); + if (ret) + goto disable_clk; + + ret = of_dma_controller_register(dev->of_node, of_dma_xlate_by_chan_id, + ddev); + if (ret) + goto unregister_dmac; + + platform_set_drvdata(pdev, mdev); + + return 0; + +unregister_dmac: + dma_async_device_unregister(ddev); +disable_clk: + clk_disable_unprepare(mdev->clk); + + return ret; +} + +static int uniphier_mdmac_remove(struct platform_device *pdev) +{ + struct uniphier_mdmac_device *mdev = platform_get_drvdata(pdev); + struct dma_chan *chan; + int ret; + + /* + * Before reaching here, almost all descriptors have been freed by the + * ->device_free_chan_resources() hook. However, each channel might + * be still holding one descriptor that was on-flight at that moment. + * Terminate it to make sure this hardware is no longer running. Then, + * free the channel resources once again to avoid memory leak. + */ + list_for_each_entry(chan, &mdev->ddev.channels, device_node) { + ret = dmaengine_terminate_sync(chan); + if (ret) + return ret; + uniphier_mdmac_free_chan_resources(chan); + } + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&mdev->ddev); + clk_disable_unprepare(mdev->clk); + + return 0; +} + +static const struct of_device_id uniphier_mdmac_match[] = { + { .compatible = "socionext,uniphier-mio-dmac" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, uniphier_mdmac_match); + +static struct platform_driver uniphier_mdmac_driver = { + .probe = uniphier_mdmac_probe, + .remove = uniphier_mdmac_remove, + .driver = { + .name = "uniphier-mio-dmac", + .of_match_table = uniphier_mdmac_match, + }, +}; +module_platform_driver(uniphier_mdmac_driver); + +MODULE_AUTHOR("Masahiro Yamada "); +MODULE_DESCRIPTION("UniPhier MIO DMAC driver"); +MODULE_LICENSE("GPL v2");