From patchwork Thu May 20 23:02:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Keguang Zhang X-Patchwork-Id: 12271507 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 A27AFC433B4 for ; Thu, 20 May 2021 23:02:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D563613B0 for ; Thu, 20 May 2021 23:02:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232827AbhETXEC (ORCPT ); Thu, 20 May 2021 19:04:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232619AbhETXEC (ORCPT ); Thu, 20 May 2021 19:04:02 -0400 Received: from mail-pl1-x632.google.com (mail-pl1-x632.google.com [IPv6:2607:f8b0:4864:20::632]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 944CAC061574; Thu, 20 May 2021 16:02:39 -0700 (PDT) Received: by mail-pl1-x632.google.com with SMTP id b7so5798810plg.0; Thu, 20 May 2021 16:02:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QhESEWNq0QZuoMD/+nbvb2Hxc08lKuOSGspufr3QET4=; b=Bk/WuQ0qDbXrMgK8dvol3N22a1lMiMoO9omeYGFNzXchgnuJ/HZqlGo6s0OZatbpeL v+KV8d4gFSmwEaHfVaV1C+XqoMP1qoAbfYnDm9vhwhBAvJeBgSqi/OjwnH5iv/G2r/Hp zknKuhv/DaPDsMhTmEprVFAqo6ectWkyWVikjsF2DmySI/I9j54TSFnAjPrLjQdYMFYw tjZt9F2eEBcfsNCtj5wbicy2tZVo86UZyHwaFv4i+L6ScHr8lr6XDO/Dg4Ndn1nR8Bix zOj1DXja1V/muNp9g61DWLhAEvEbjCPYu4LSZAktr5Ttw0ZfCk3iMkybBvJ1Kmb8Vm6e lAqQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QhESEWNq0QZuoMD/+nbvb2Hxc08lKuOSGspufr3QET4=; b=EfHYcCI7PleSuMnQAoAtIYC44scasCQjsuGE9PKzz0xxETwxsECpUialY7668iwjCA BCXzFjcU49/Aa/JCKdinAZXjjNWw2U0TD2fhHAYb17htCCXZBQQzK7k8HUuNwcqLme+f xVCegA+blc7dvW7T8JEa0h3DHvSiETeKmKjWnoGvcgQnEzpkJWFLLvAvj1saf7klGU4Z fphLZ2SkNp/qfCa9N83Dw26g0MP9ynyq/Xi3LM2HV3l8IQLyPAZjFXOmLArmRsZaYhEo Yy/DlDwlh8plKI6XqfmCJQa7uCSHfQWclsnnz85wicNvwKWjISVVAi1D3CHcFPlY/xED Xt2g== X-Gm-Message-State: AOAM533rHyAqOva3oTkf6Oe92VXWTg9VcVMM6dS+2em1+peN3/M+jiPZ Ali3ThDhoPbb27hu1cZUpVYt9dLJSgy63g== X-Google-Smtp-Source: ABdhPJwswUlJQ52Yx2IwQucl/Vxrp+E8ukwZ7A4CGNkRPr9kEW1PUuybmkLlov0NVmDTn5wvfNlsYw== X-Received: by 2002:a17:903:4106:b029:e9:244f:9aca with SMTP id r6-20020a1709034106b02900e9244f9acamr8624559pld.58.1621551758300; Thu, 20 May 2021 16:02:38 -0700 (PDT) Received: from kelvin-System-Product-Name.lan ([117.173.227.56]) by smtp.gmail.com with ESMTPSA id e34sm3604276pjk.31.2021.05.20.16.02.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 20 May 2021 16:02:37 -0700 (PDT) From: Keguang Zhang To: dmaengine@vger.kernel.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Vinod Koul , Kelvin Cheung Subject: [PATCH V4 RESEND] dmaengine: Loongson1: Add Loongson1 dmaengine driver Date: Fri, 21 May 2021 07:02:25 +0800 Message-Id: <20210520230225.11911-1-keguang.zhang@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org From: Kelvin Cheung This patch adds DMA Engine driver for Loongson1B. Signed-off-by: Kelvin Cheung --- V3 -> V4: Use dma_slave_map to find the proper channel. Explicitly call devm_request_irq() and tasklet_kill(). Fix namespace issue. Some minor fixes and cleanups. V2 -> V3: Rename ls1x_dma_filter_fn to ls1x_dma_filter. V1 -> V2: Change the config from 'DMA_LOONGSON1' to 'LOONGSON1_DMA', and rearrange it in alphabetical order in Kconfig and Makefile. Fix comment style. --- drivers/dma/Kconfig | 9 + drivers/dma/Makefile | 1 + drivers/dma/loongson1-dma.c | 514 ++++++++++++++++++++++++++++++++++++ 3 files changed, 524 insertions(+) create mode 100644 drivers/dma/loongson1-dma.c base-commit: 6f64aa5746d254f2b9b94b837b7862549f2565a0 diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 6ab9d9a488a6..b3ceeae61483 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -343,6 +343,15 @@ config K3_DMA Support the DMA engine for Hisilicon K3 platform devices. +config LOONGSON1_DMA + tristate "Loongson1 DMA support" + depends on MACH_LOONGSON32 + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + This selects support for the DMA controller in Loongson1 SoCs, + and is required by Loongson1 NAND controller and AC97 support. + config LPC18XX_DMAMUX bool "NXP LPC18xx/43xx DMA MUX for PL080" depends on ARCH_LPC18XX || COMPILE_TEST diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index aa69094e3547..6d54e485036e 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_INTEL_IOATDMA) += ioat/ obj-$(CONFIG_INTEL_IDXD) += idxd/ obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o obj-$(CONFIG_K3_DMA) += k3dma.o +obj-$(CONFIG_LOONGSON1_DMA) += loongson1-dma.o obj-$(CONFIG_LPC18XX_DMAMUX) += lpc18xx-dmamux.o obj-$(CONFIG_MILBEAUT_HDMAC) += milbeaut-hdmac.o obj-$(CONFIG_MILBEAUT_XDMAC) += milbeaut-xdmac.o diff --git a/drivers/dma/loongson1-dma.c b/drivers/dma/loongson1-dma.c new file mode 100644 index 000000000000..5899509125fe --- /dev/null +++ b/drivers/dma/loongson1-dma.c @@ -0,0 +1,514 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * DMA Driver for Loongson 1 SoC + * + * Copyright (C) 2015-2021 Zhang, Keguang + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "dmaengine.h" +#include "virt-dma.h" + +/* Loongson 1 DMA Register Definitions */ +#define LS1X_DMA_CTRL 0x0 + +/* DMA Control Register Bits */ +#define LS1X_DMA_STOP BIT(4) +#define LS1X_DMA_START BIT(3) + +#define LS1X_DMA_ADDR_MASK GENMASK(31, 6) + +/* DMA Command Register Bits */ +#define LS1X_DMA_RAM2DEV BIT(12) +#define LS1X_DMA_TRANS_OVER BIT(3) +#define LS1X_DMA_SINGLE_TRANS_OVER BIT(2) +#define LS1X_DMA_INT BIT(1) +#define LS1X_DMA_INT_MASK BIT(0) + +struct ls1x_dma_lli { + u32 next; /* next descriptor address */ + u32 saddr; /* memory DMA address */ + u32 daddr; /* device DMA address */ + u32 length; + u32 stride; + u32 cycles; + u32 cmd; +} __aligned(64); + +struct ls1x_dma_hwdesc { + struct ls1x_dma_lli *lli; + dma_addr_t phys; +}; + +struct ls1x_dma_desc { + struct virt_dma_desc vdesc; + struct ls1x_dma_chan *chan; + + enum dma_transfer_direction dir; + enum dma_transaction_type type; + + unsigned int nr_descs; /* number of descriptors */ + unsigned int nr_done; /* number of completed descriptors */ + struct ls1x_dma_hwdesc hwdesc[]; /* DMA coherent descriptors */ +}; + +struct ls1x_dma_chan { + struct virt_dma_chan vchan; + struct dma_pool *desc_pool; + struct dma_slave_config cfg; + + unsigned int id; + void __iomem *reg_base; + unsigned int irq; + + struct ls1x_dma_desc *desc; +}; + +struct ls1x_dma { + struct dma_device ddev; + struct clk *clk; + void __iomem *reg_base; + + unsigned int nr_chans; + struct ls1x_dma_chan chan[]; +}; + +#define to_ls1x_dma_chan(dchan) \ + container_of(dchan, struct ls1x_dma_chan, vchan.chan) + +#define to_ls1x_dma_desc(vdesc) \ + container_of(vdesc, struct ls1x_dma_desc, vdesc) + +/* macros for registers read/write */ +#define chan_readl(chan, off) \ + readl((chan)->reg_base + (off)) + +#define chan_writel(chan, off, val) \ + writel((val), (chan)->reg_base + (off)) + +static bool ls1x_dma_filter(struct dma_chan *chan, void *param); + +static inline struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} + +static void ls1x_dma_free_chan_resources(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + + vchan_free_chan_resources(&chan->vchan); + dma_pool_destroy(chan->desc_pool); + chan->desc_pool = NULL; +} + +static int ls1x_dma_alloc_chan_resources(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + + chan->desc_pool = dma_pool_create(dma_chan_name(dchan), + dchan->device->dev, + sizeof(struct ls1x_dma_lli), + __alignof__(struct ls1x_dma_lli), 0); + if (!chan->desc_pool) { + dev_err(chan2dev(dchan), + "failed to alloc DMA descriptor pool!\n"); + return -ENOMEM; + } + + return 0; +} + +static void ls1x_dma_free_desc(struct virt_dma_desc *vdesc) +{ + struct ls1x_dma_desc *desc = to_ls1x_dma_desc(vdesc); + + if (desc->nr_descs) { + unsigned int i = desc->nr_descs; + struct ls1x_dma_hwdesc *hwdesc; + + do { + hwdesc = &desc->hwdesc[--i]; + dma_pool_free(desc->chan->desc_pool, hwdesc->lli, + hwdesc->phys); + } while (i); + } + + kfree(desc); +} + +static struct ls1x_dma_desc *ls1x_dma_alloc_desc(struct ls1x_dma_chan *chan, + int sg_len) +{ + struct ls1x_dma_desc *desc; + struct dma_chan *dchan = &chan->vchan.chan; + + desc = kzalloc(struct_size(desc, hwdesc, sg_len), GFP_NOWAIT); + if (!desc) + dev_err(chan2dev(dchan), "failed to alloc DMA descriptor!\n"); + + return desc; +} + +static struct dma_async_tx_descriptor * +ls1x_dma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, + unsigned int sg_len, + enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + struct dma_slave_config *cfg = &chan->cfg; + struct ls1x_dma_desc *desc; + struct scatterlist *sg; + unsigned int dev_addr, bus_width, cmd, i; + + if (!is_slave_direction(direction)) { + dev_err(chan2dev(dchan), "invalid DMA direction!\n"); + return NULL; + } + + dev_dbg(chan2dev(dchan), "sg_len=%d, dir=%s, flags=0x%lx\n", sg_len, + direction == DMA_MEM_TO_DEV ? "to device" : "from device", + flags); + + switch (direction) { + case DMA_MEM_TO_DEV: + dev_addr = cfg->dst_addr; + bus_width = cfg->dst_addr_width; + cmd = LS1X_DMA_RAM2DEV | LS1X_DMA_INT; + break; + case DMA_DEV_TO_MEM: + dev_addr = cfg->src_addr; + bus_width = cfg->src_addr_width; + cmd = LS1X_DMA_INT; + break; + default: + dev_err(chan2dev(dchan), + "unsupported DMA transfer mode! %d\n", direction); + return NULL; + } + + /* allocate DMA descriptor */ + desc = ls1x_dma_alloc_desc(chan, sg_len); + if (!desc) + return NULL; + + for_each_sg(sgl, sg, sg_len, i) { + dma_addr_t buf_addr = sg_dma_address(sg); + size_t buf_len = sg_dma_len(sg); + struct ls1x_dma_hwdesc *hwdesc = &desc->hwdesc[i]; + struct ls1x_dma_lli *lli; + + if (!is_dma_copy_aligned(dchan->device, buf_addr, 0, buf_len)) { + dev_err(chan2dev(dchan), "%s: buffer is not aligned!\n", + __func__); + goto err; + } + + /* allocate HW DMA descriptors */ + lli = dma_pool_alloc(chan->desc_pool, GFP_NOWAIT, + &hwdesc->phys); + if (!lli) { + dev_err(chan2dev(dchan), + "%s: failed to alloc HW DMA descriptor!\n", + __func__); + goto err; + } + hwdesc->lli = lli; + + /* config HW DMA descriptors */ + lli->saddr = buf_addr; + lli->daddr = dev_addr; + lli->length = buf_len / bus_width; + lli->stride = 0; + lli->cycles = 1; + lli->cmd = cmd; + lli->next = 0; + + if (i) + desc->hwdesc[i - 1].lli->next = hwdesc->phys; + + dev_dbg(chan2dev(dchan), + "hwdesc=%px, saddr=%08x, daddr=%08x, length=%u\n", + hwdesc, buf_addr, dev_addr, buf_len); + } + + /* config DMA descriptor */ + desc->chan = chan; + desc->dir = direction; + desc->type = DMA_SLAVE; + desc->nr_descs = sg_len; + desc->nr_done = 0; + + return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); +err: + desc->nr_descs = i; + ls1x_dma_free_desc(&desc->vdesc); + return NULL; +} + +static int ls1x_dma_slave_config(struct dma_chan *dchan, + struct dma_slave_config *config) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + + if (!dchan) + return -EINVAL; + + chan->cfg = *config; + + return 0; +} + +static int ls1x_dma_terminate_all(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&chan->vchan.lock, flags); + + chan_writel(chan, LS1X_DMA_CTRL, + chan_readl(chan, LS1X_DMA_CTRL) | LS1X_DMA_STOP); + chan->desc = NULL; + vchan_get_all_descriptors(&chan->vchan, &head); + + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + vchan_dma_desc_free_list(&chan->vchan, &head); + + return 0; +} + +static void ls1x_dma_trigger(struct ls1x_dma_chan *chan) +{ + struct dma_chan *dchan = &chan->vchan.chan; + struct ls1x_dma_desc *desc; + struct virt_dma_desc *vdesc; + unsigned int val; + + vdesc = vchan_next_desc(&chan->vchan); + if (!vdesc) { + dev_warn(chan2dev(dchan), "No pending descriptor\n"); + return; + } + chan->desc = desc = to_ls1x_dma_desc(vdesc); + + dev_dbg(chan2dev(dchan), "cookie=%d, %u descs, starting hwdesc=%px\n", + dchan->cookie, desc->nr_descs, &desc->hwdesc[0]); + + val = desc->hwdesc[0].phys & LS1X_DMA_ADDR_MASK; + val |= chan->id; + val |= LS1X_DMA_START; + chan_writel(chan, LS1X_DMA_CTRL, val); +} + +static void ls1x_dma_issue_pending(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + unsigned long flags; + + spin_lock_irqsave(&chan->vchan.lock, flags); + + if (vchan_issue_pending(&chan->vchan) && !chan->desc) + ls1x_dma_trigger(chan); + + spin_unlock_irqrestore(&chan->vchan.lock, flags); +} + +static irqreturn_t ls1x_dma_irq_handler(int irq, void *data) +{ + struct ls1x_dma_chan *chan = data; + struct dma_chan *dchan = &chan->vchan.chan; + + dev_dbg(chan2dev(dchan), "DMA IRQ %d on channel %d\n", irq, chan->id); + if (!chan->desc) { + dev_warn(chan2dev(dchan), + "DMA IRQ with no active descriptor on channel %d\n", + chan->id); + return IRQ_NONE; + } + + spin_lock(&chan->vchan.lock); + + if (chan->desc->type == DMA_CYCLIC) { + vchan_cyclic_callback(&chan->desc->vdesc); + } else { + list_del(&chan->desc->vdesc.node); + vchan_cookie_complete(&chan->desc->vdesc); + chan->desc = NULL; + } + + spin_unlock(&chan->vchan.lock); + return IRQ_HANDLED; +} + +static int ls1x_dma_chan_probe(struct platform_device *pdev, + struct ls1x_dma *dma, int chan_id) +{ + struct device *dev = &pdev->dev; + struct ls1x_dma_chan *chan = &dma->chan[chan_id]; + char *irq_name; + int ret; + + chan->irq = platform_get_irq(pdev, chan_id); + if (chan->irq < 0) { + dev_err(dev, "failed to get IRQ %d!\n", chan->irq); + return ret; + } + + irq_name = devm_kasprintf(dev, GFP_KERNEL, "%s:ch%u", + dev_name(dev), chan_id); + if (!irq_name) + return -ENOMEM; + + ret = devm_request_irq(dev, chan->irq, ls1x_dma_irq_handler, + IRQF_SHARED, irq_name, chan); + if (ret) { + dev_err(dev, "failed to request IRQ %u!\n", chan->irq); + return ret; + } + + chan->id = chan_id; + chan->reg_base = dma->reg_base; + chan->vchan.desc_free = ls1x_dma_free_desc; + vchan_init(&chan->vchan, &dma->ddev); + dev_info(dev, "channel %d (irq %d) initialized\n", chan->id, chan->irq); + + return 0; +} + +static void ls1x_dma_chan_remove(struct ls1x_dma *dma, int chan_id) +{ + struct device *dev = dma->ddev.dev; + struct ls1x_dma_chan *chan = &dma->chan[chan_id]; + + devm_free_irq(dev, chan->irq, chan); + list_del(&chan->vchan.chan.device_node); + tasklet_kill(&chan->vchan.task); +} + +static int ls1x_dma_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct plat_ls1x_dma *pdata; + struct dma_device *ddev; + struct ls1x_dma *dma; + int nr_chans, ret, i; + + pdata = dev_get_platdata(dev); + if (!pdata) { + dev_err(dev, "platform data missing!\n"); + return -EINVAL; + } + + nr_chans = platform_irq_count(pdev); + if (nr_chans <= 0) + return nr_chans; + + dma = devm_kzalloc(dev, struct_size(dma, chan, nr_chans), GFP_KERNEL); + if (!dma) + return -ENOMEM; + + /* initialize DMA device */ + dma->reg_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(dma->reg_base)) + return PTR_ERR(dma->reg_base); + + ddev = &dma->ddev; + ddev->dev = dev; + ddev->copy_align = DMAENGINE_ALIGN_16_BYTES; + ddev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); + ddev->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); + ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; + ddev->device_alloc_chan_resources = ls1x_dma_alloc_chan_resources; + ddev->device_free_chan_resources = ls1x_dma_free_chan_resources; + ddev->device_prep_slave_sg = ls1x_dma_prep_slave_sg; + ddev->device_config = ls1x_dma_slave_config; + ddev->device_terminate_all = ls1x_dma_terminate_all; + ddev->device_tx_status = dma_cookie_status; + ddev->device_issue_pending = ls1x_dma_issue_pending; + ddev->filter.map = pdata->slave_map; + ddev->filter.mapcnt = pdata->slavecnt; + ddev->filter.fn = ls1x_dma_filter; + + dma_cap_set(DMA_SLAVE, ddev->cap_mask); + INIT_LIST_HEAD(&ddev->channels); + + /* initialize DMA channels */ + for (i = 0; i < nr_chans; i++) { + ret = ls1x_dma_chan_probe(pdev, dma, i); + if (ret) + return ret; + } + dma->nr_chans = nr_chans; + + dma->clk = devm_clk_get(dev, pdev->name); + if (IS_ERR(dma->clk)) { + dev_err(dev, "failed to get %s clock!\n", pdev->name); + return PTR_ERR(dma->clk); + } + clk_prepare_enable(dma->clk); + + ret = dma_async_device_register(ddev); + if (ret) { + dev_err(dev, "failed to register DMA device! %d\n", ret); + clk_disable_unprepare(dma->clk); + return ret; + } + + platform_set_drvdata(pdev, dma); + dev_info(dev, "Loongson1 DMA driver registered\n"); + + return 0; +} + +static int ls1x_dma_remove(struct platform_device *pdev) +{ + struct ls1x_dma *dma = platform_get_drvdata(pdev); + int i; + + dma_async_device_unregister(&dma->ddev); + clk_disable_unprepare(dma->clk); + for (i = 0; i < dma->nr_chans; i++) + ls1x_dma_chan_remove(dma, i); + + return 0; +} + +static struct platform_driver ls1x_dma_driver = { + .probe = ls1x_dma_probe, + .remove = ls1x_dma_remove, + .driver = { + .name = "ls1x-dma", + }, +}; + +module_platform_driver(ls1x_dma_driver); + +static bool ls1x_dma_filter(struct dma_chan *dchan, void *param) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + unsigned int chan_id = (unsigned int)param; + + if (dchan->device->dev->driver != &ls1x_dma_driver.driver) + return false; + + return chan_id == chan->id; +} + +MODULE_AUTHOR("Kelvin Cheung "); +MODULE_DESCRIPTION("Loongson1 DMA driver"); +MODULE_LICENSE("GPL");