--- /dev/null
+/*
+ * Driver for the Analog Devices AXI-DMAC core
+ *
+ * Copyright 2013-2015 Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/dma/axi-dmac.h>
+
+#include "dmaengine.h"
+#include "virt-dma.h"
+
+/*
+ * The AXI-DMAC is a soft IP core that is used in FPGA designs. The core has
+ * various instantiation parameters which decided the exact feature set support
+ * by the core.
+ *
+ * Each channel of the core has a source interface and a destination interface.
+ * The number of channels and the type of the channel interfaces is selected at
+ * configuration time. A interface can either be a connected to a central memory
+ * interconnect, which allows access to system memory, or it can be connected to
+ * a dedicated bus which is directly connected to a data port on a peripheral.
+ * Given that those are configuration options of the core that are selected when
+ * it is instantiated this means that they can not be changed by software at
+ * runtime. By extension this means that each channel is uni-directional. It can
+ * either be device to memory or memory to device, but not both. Also since the
+ * device side is a dedicated data bus only connected to a single peripheral
+ * there is no address than can or needs to be configured for the device side.
+ */
+
+#define AXI_DMAC_REG_IRQ_MASK 0x80
+#define AXI_DMAC_REG_IRQ_PENDING 0x84
+#define AXI_DMAC_REG_IRQ_SOURCE 0x88
+
+#define AXI_DMAC_REG_CTRL 0x400
+#define AXI_DMAC_REG_TRANSFER_ID 0x404
+#define AXI_DMAC_REG_START_TRANSFER 0x408
+#define AXI_DMAC_REG_FLAGS 0x40c
+#define AXI_DMAC_REG_DEST_ADDRESS 0x410
+#define AXI_DMAC_REG_SRC_ADDRESS 0x414
+#define AXI_DMAC_REG_X_LENGTH 0x418
+#define AXI_DMAC_REG_Y_LENGTH 0x41c
+#define AXI_DMAC_REG_DEST_STRIDE 0x420
+#define AXI_DMAC_REG_SRC_STRIDE 0x424
+#define AXI_DMAC_REG_TRANSFER_DONE 0x428
+#define AXI_DMAC_REG_ACTIVE_TRANSFER_ID 0x42c
+#define AXI_DMAC_REG_STATUS 0x430
+#define AXI_DMAC_REG_CURRENT_SRC_ADDR 0x434
+#define AXI_DMAC_REG_CURRENT_DEST_ADDR 0x438
+
+#define AXI_DMAC_CTRL_ENABLE BIT(0)
+#define AXI_DMAC_CTRL_PAUSE BIT(1)
+
+#define AXI_DMAC_IRQ_SOT BIT(0)
+#define AXI_DMAC_IRQ_EOT BIT(1)
+
+#define AXI_DMAC_FLAG_CYCLIC BIT(0)
+
+struct axi_dmac_sg {
+ dma_addr_t src_addr;
+ dma_addr_t dest_addr;
+ unsigned int x_len;
+ unsigned int y_len;
+ unsigned int dest_stride;
+ unsigned int src_stride;
+ unsigned int id;
+};
+
+struct axi_dmac_desc {
+ struct virt_dma_desc vdesc;
+ bool cyclic;
+
+ unsigned int num_submitted;
+ unsigned int num_completed;
+ unsigned int num_sgs;
+ struct axi_dmac_sg sg[];
+};
+
+struct axi_dmac_chan {
+ struct virt_dma_chan vchan;
+
+ struct axi_dmac_desc *next_desc;
+ struct list_head active_descs;
+ enum dma_transfer_direction direction;
+
+ unsigned int src_width;
+ unsigned int dest_width;
+ unsigned int src_type;
+ unsigned int dest_type;
+
+ unsigned int max_length;
+ unsigned int align_mask;
+
+ bool hw_cyclic;
+ bool hw_2d;
+};
+
+struct axi_dmac {
+ void __iomem *base;
+ int irq;
+
+ struct clk *clk;
+
+ struct dma_device dma_dev;
+ struct axi_dmac_chan chan;
+
+ struct device_dma_parameters dma_parms;
+};
+
+static struct axi_dmac *chan_to_axi_dmac(struct axi_dmac_chan *chan)
+{
+ return container_of(chan->vchan.chan.device, struct axi_dmac,
+ dma_dev);
+}
+
+static struct axi_dmac_chan *to_axi_dmac_chan(struct dma_chan *c)
+{
+ return container_of(c, struct axi_dmac_chan, vchan.chan);
+}
+
+static struct axi_dmac_desc *to_axi_dmac_desc(struct virt_dma_desc *vdesc)
+{
+ return container_of(vdesc, struct axi_dmac_desc, vdesc);
+}
+
+static void axi_dmac_write(struct axi_dmac *axi_dmac, unsigned int reg,
+ unsigned int val)
+{
+ writel(val, axi_dmac->base + reg);
+}
+
+static int axi_dmac_read(struct axi_dmac *axi_dmac, unsigned int reg)
+{
+ return readl(axi_dmac->base + reg);
+}
+
+static int axi_dmac_src_is_mem(struct axi_dmac_chan *chan)
+{
+ return chan->src_type == AXI_DMAC_BUS_TYPE_AXI_MM;
+}
+
+static int axi_dmac_dest_is_mem(struct axi_dmac_chan *chan)
+{
+ return chan->dest_type == AXI_DMAC_BUS_TYPE_AXI_MM;
+}
+
+static bool axi_dmac_check_len(struct axi_dmac_chan *chan, unsigned int len)
+{
+ if (len == 0 || len > chan->max_length)
+ return false;
+ if ((len & chan->align_mask) != 0) /* Not aligned */
+ return false;
+ return true;
+}
+
+static bool axi_dmac_check_addr(struct axi_dmac_chan *chan, dma_addr_t addr)
+{
+ if ((addr & chan->align_mask) != 0) /* Not aligned */
+ return false;
+ return true;
+}
+
+static void axi_dmac_start_transfer(struct axi_dmac_chan *chan)
+{
+ struct axi_dmac *dmac = chan_to_axi_dmac(chan);
+ struct virt_dma_desc *vdesc;
+ struct axi_dmac_desc *desc;
+ struct axi_dmac_sg *sg;
+ unsigned int flags = 0;
+ unsigned int val;
+
+ val = axi_dmac_read(dmac, AXI_DMAC_REG_START_TRANSFER);
+ if (val) /* Queue is full, wait for the next SOT IRQ */
+ return;
+
+ desc = chan->next_desc;
+
+ if (!desc) {
+ vdesc = vchan_next_desc(&chan->vchan);
+ if (!vdesc)
+ return;
+ list_move_tail(&vdesc->node, &chan->active_descs);
+ desc = to_axi_dmac_desc(vdesc);
+ }
+ sg = &desc->sg[desc->num_submitted];
+
+ desc->num_submitted++;
+ if (desc->num_submitted == desc->num_sgs)
+ chan->next_desc = NULL;
+ else
+ chan->next_desc = desc;
+
+ sg->id = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_ID);
+
+ if (axi_dmac_dest_is_mem(chan)) {
+ axi_dmac_write(dmac, AXI_DMAC_REG_DEST_ADDRESS, sg->dest_addr);
+ axi_dmac_write(dmac, AXI_DMAC_REG_DEST_STRIDE, sg->dest_stride);
+ }
+
+ if (axi_dmac_src_is_mem(chan)) {
+ axi_dmac_write(dmac, AXI_DMAC_REG_SRC_ADDRESS, sg->src_addr);
+ axi_dmac_write(dmac, AXI_DMAC_REG_SRC_STRIDE, sg->src_stride);
+ }
+
+ /*
+ * If the hardware supports cyclic transfers and there is no callback to
+ * call, enable hw cyclic mode to avoid unnecessary interrupts.
+ */
+ if (chan->hw_cyclic && desc->cyclic && !desc->vdesc.tx.callback)
+ flags |= AXI_DMAC_FLAG_CYCLIC;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, sg->x_len - 1);
+ axi_dmac_write(dmac, AXI_DMAC_REG_Y_LENGTH, sg->y_len - 1);
+ axi_dmac_write(dmac, AXI_DMAC_REG_FLAGS, flags);
+ axi_dmac_write(dmac, AXI_DMAC_REG_START_TRANSFER, 1);
+}
+
+static struct axi_dmac_desc *axi_dmac_active_desc(struct axi_dmac_chan *chan)
+{
+ return list_first_entry_or_null(&chan->active_descs,
+ struct axi_dmac_desc, vdesc.node);
+}
+
+static void axi_dmac_transfer_done(struct axi_dmac_chan *chan,
+ unsigned int completed_transfers)
+{
+ struct axi_dmac_desc *active;
+ struct axi_dmac_sg *sg;
+
+ active = axi_dmac_active_desc(chan);
+ if (!active)
+ return;
+
+ if (active->cyclic) {
+ vchan_cyclic_callback(&active->vdesc);
+ } else {
+ do {
+ sg = &active->sg[active->num_completed];
+ if (!(BIT(sg->id) & completed_transfers))
+ break;
+ active->num_completed++;
+ if (active->num_completed == active->num_sgs) {
+ list_del(&active->vdesc.node);
+ vchan_cookie_complete(&active->vdesc);
+ active = axi_dmac_active_desc(chan);
+ }
+ } while (active);
+ }
+}
+
+static irqreturn_t axi_dmac_interrupt_handler(int irq, void *devid)
+{
+ struct axi_dmac *dmac = devid;
+ unsigned int pending;
+
+ pending = axi_dmac_read(dmac, AXI_DMAC_REG_IRQ_PENDING);
+ axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_PENDING, pending);
+
+ spin_lock(&dmac->chan.vchan.lock);
+ /* One or more transfers have finished */
+ if (pending & AXI_DMAC_IRQ_EOT) {
+ unsigned int completed;
+
+ completed = axi_dmac_read(dmac, AXI_DMAC_REG_TRANSFER_DONE);
+ axi_dmac_transfer_done(&dmac->chan, completed);
+ }
+ /* Space has become available in the descriptor queue */
+ if (pending & AXI_DMAC_IRQ_SOT)
+ axi_dmac_start_transfer(&dmac->chan);
+ spin_unlock(&dmac->chan.vchan.lock);
+
+ return IRQ_HANDLED;
+}
+
+static int axi_dmac_terminate_all(struct dma_chan *c)
+{
+ struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
+ struct axi_dmac *dmac = chan_to_axi_dmac(chan);
+ unsigned long flags;
+ LIST_HEAD(head);
+
+ spin_lock_irqsave(&chan->vchan.lock, flags);
+ axi_dmac_write(dmac, AXI_DMAC_REG_CTRL, 0);
+ chan->next_desc = NULL;
+ vchan_get_all_descriptors(&chan->vchan, &head);
+ list_splice_tail_init(&chan->active_descs, &head);
+ spin_unlock_irqrestore(&chan->vchan.lock, flags);
+
+ vchan_dma_desc_free_list(&chan->vchan, &head);
+
+ return 0;
+}
+
+static void axi_dmac_issue_pending(struct dma_chan *c)
+{
+ struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
+ struct axi_dmac *dmac = chan_to_axi_dmac(chan);
+ unsigned long flags;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_CTRL, AXI_DMAC_CTRL_ENABLE);
+
+ spin_lock_irqsave(&chan->vchan.lock, flags);
+ if (vchan_issue_pending(&chan->vchan))
+ axi_dmac_start_transfer(chan);
+ spin_unlock_irqrestore(&chan->vchan.lock, flags);
+}
+
+static struct axi_dmac_desc *axi_dmac_alloc_desc(unsigned int num_sgs)
+{
+ struct axi_dmac_desc *desc;
+
+ desc = kzalloc(sizeof(struct axi_dmac_desc) +
+ sizeof(struct axi_dmac_sg) * num_sgs, GFP_NOWAIT);
+ if (!desc)
+ return NULL;
+
+ desc->num_sgs = num_sgs;
+
+ return desc;
+}
+
+static struct dma_async_tx_descriptor *axi_dmac_prep_slave_sg(
+ struct dma_chan *c, struct scatterlist *sgl,
+ unsigned int sg_len, enum dma_transfer_direction direction,
+ unsigned long flags, void *context)
+{
+ struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
+ struct axi_dmac_desc *desc;
+ struct scatterlist *sg;
+ unsigned int i;
+
+ if (direction != chan->direction)
+ return NULL;
+
+ desc = axi_dmac_alloc_desc(sg_len);
+ if (!desc)
+ return NULL;
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ if (!axi_dmac_check_addr(chan, sg_dma_address(sg)) ||
+ !axi_dmac_check_len(chan, sg_dma_len(sg))) {
+ kfree(desc);
+ return NULL;
+ }
+
+ if (direction == DMA_DEV_TO_MEM)
+ desc->sg[i].dest_addr = sg_dma_address(sg);
+ else
+ desc->sg[i].src_addr = sg_dma_address(sg);
+ desc->sg[i].x_len = sg_dma_len(sg);
+ desc->sg[i].y_len = 1;
+ }
+
+ desc->cyclic = false;
+
+ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
+}
+
+static struct dma_async_tx_descriptor *axi_dmac_prep_dma_cyclic(
+ struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
+ size_t period_len, enum dma_transfer_direction direction,
+ unsigned long flags)
+{
+ struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
+ struct axi_dmac_desc *desc;
+ unsigned int num_periods, i;
+
+ if (direction != chan->direction)
+ return NULL;
+
+ if (!axi_dmac_check_len(chan, buf_len) ||
+ !axi_dmac_check_addr(chan, buf_addr))
+ return NULL;
+
+ if (period_len == 0 || buf_len % period_len)
+ return NULL;
+
+ num_periods = buf_len / period_len;
+
+ desc = axi_dmac_alloc_desc(num_periods);
+ if (!desc)
+ return NULL;
+
+ for (i = 0; i < num_periods; i++) {
+ if (direction == DMA_DEV_TO_MEM)
+ desc->sg[i].dest_addr = buf_addr;
+ else
+ desc->sg[i].src_addr = buf_addr;
+ desc->sg[i].x_len = period_len;
+ desc->sg[i].y_len = 1;
+ buf_addr += period_len;
+ }
+
+ desc->cyclic = true;
+
+ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
+}
+
+static struct dma_async_tx_descriptor *axi_dmac_prep_interleaved(
+ struct dma_chan *c, struct dma_interleaved_template *xt,
+ unsigned long flags)
+{
+ struct axi_dmac_chan *chan = to_axi_dmac_chan(c);
+ struct axi_dmac_desc *desc;
+ size_t dst_icg, src_icg;
+
+ if (xt->frame_size != 1)
+ return NULL;
+
+ if (xt->dir != chan->direction)
+ return NULL;
+
+ if (axi_dmac_src_is_mem(chan)) {
+ if (!xt->src_inc || !axi_dmac_check_addr(chan, xt->src_start))
+ return NULL;
+ }
+
+ if (axi_dmac_dest_is_mem(chan)) {
+ if (!xt->dst_inc || !axi_dmac_check_addr(chan, xt->dst_start))
+ return NULL;
+ }
+
+ dst_icg = dmaengine_get_dst_icg(xt, &xt->sgl[0]);
+ src_icg = dmaengine_get_src_icg(xt, &xt->sgl[0]);
+
+ if (chan->hw_2d) {
+ if (!axi_dmac_check_len(chan, xt->sgl[0].size) ||
+ !axi_dmac_check_len(chan, xt->numf))
+ return NULL;
+ if (xt->sgl[0].size + dst_icg > chan->max_length ||
+ xt->sgl[0].size + src_icg > chan->max_length)
+ return NULL;
+ } else {
+ if (dst_icg != 0 || src_icg != 0)
+ return NULL;
+ if (chan->max_length / xt->sgl[0].size < xt->numf)
+ return NULL;
+ if (!axi_dmac_check_len(chan, xt->sgl[0].size * xt->numf))
+ return NULL;
+ }
+
+ desc = axi_dmac_alloc_desc(1);
+ if (!desc)
+ return NULL;
+
+ if (axi_dmac_src_is_mem(chan)) {
+ desc->sg[0].src_addr = xt->src_start;
+ desc->sg[0].src_stride = xt->sgl[0].size + src_icg;
+ }
+
+ if (axi_dmac_dest_is_mem(chan)) {
+ desc->sg[0].dest_addr = xt->dst_start;
+ desc->sg[0].dest_stride = xt->sgl[0].size + dst_icg;
+ }
+
+ if (chan->hw_2d) {
+ desc->sg[0].x_len = xt->sgl[0].size;
+ desc->sg[0].y_len = xt->numf;
+ } else {
+ desc->sg[0].x_len = xt->sgl[0].size * xt->numf;
+ desc->sg[0].y_len = 1;
+ }
+
+ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
+}
+
+static void axi_dmac_free_chan_resources(struct dma_chan *c)
+{
+ vchan_free_chan_resources(to_virt_chan(c));
+}
+
+static void axi_dmac_desc_free(struct virt_dma_desc *vdesc)
+{
+ kfree(container_of(vdesc, struct axi_dmac_desc, vdesc));
+}
+
+/*
+ * The configuration stored in the devicetree matches the configuration
+ * parameters of the peripheral instance and allows the driver to know which
+ * features are implemented and how it should behave.
+ */
+static int axi_dmac_parse_chan_dt(struct device_node *of_chan,
+ struct axi_dmac_chan *chan)
+{
+ u32 val;
+ int ret;
+
+ ret = of_property_read_u32(of_chan, "reg", &val);
+ if (ret)
+ return ret;
+
+ /* We only support 1 channel for now */
+ if (val != 0)
+ return -EINVAL;
+
+ ret = of_property_read_u32(of_chan, "adi,source-bus-type", &val);
+ if (ret)
+ return ret;
+ if (val > AXI_DMAC_BUS_TYPE_FIFO)
+ return -EINVAL;
+ chan->src_type = val;
+
+ ret = of_property_read_u32(of_chan, "adi,destination-bus-type", &val);
+ if (ret)
+ return ret;
+ if (val > AXI_DMAC_BUS_TYPE_FIFO)
+ return -EINVAL;
+ chan->dest_type = val;
+
+ ret = of_property_read_u32(of_chan, "adi,source-bus-width", &val);
+ if (ret)
+ return ret;
+ chan->src_width = val / 8;
+
+ ret = of_property_read_u32(of_chan, "adi,destination-bus-width", &val);
+ if (ret)
+ return ret;
+ chan->dest_width = val / 8;
+
+ ret = of_property_read_u32(of_chan, "adi,length-width", &val);
+ if (ret)
+ return ret;
+
+ if (val >= 32)
+ chan->max_length = UINT_MAX;
+ else
+ chan->max_length = (1ULL << val) - 1;
+
+ chan->align_mask = max(chan->dest_width, chan->src_width) - 1;
+
+ if (axi_dmac_dest_is_mem(chan) && axi_dmac_src_is_mem(chan))
+ chan->direction = DMA_MEM_TO_MEM;
+ else if (!axi_dmac_dest_is_mem(chan) && axi_dmac_src_is_mem(chan))
+ chan->direction = DMA_MEM_TO_DEV;
+ else if (axi_dmac_dest_is_mem(chan) && !axi_dmac_src_is_mem(chan))
+ chan->direction = DMA_DEV_TO_MEM;
+ else
+ chan->direction = DMA_DEV_TO_DEV;
+
+ chan->hw_cyclic = of_property_read_bool(of_chan, "adi,cyclic");
+ chan->hw_2d = of_property_read_bool(of_chan, "adi,2d");
+
+ return 0;
+}
+
+static int axi_dmac_probe(struct platform_device *pdev)
+{
+ struct device_node *of_channels, *of_chan;
+ struct dma_device *dma_dev;
+ struct axi_dmac *dmac;
+ struct resource *res;
+ int ret;
+
+ dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL);
+ if (!dmac)
+ return -ENOMEM;
+
+ dmac->irq = platform_get_irq(pdev, 0);
+ if (dmac->irq <= 0)
+ return -EINVAL;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ dmac->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(dmac->base))
+ return PTR_ERR(dmac->base);
+
+ dmac->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(dmac->clk))
+ return PTR_ERR(dmac->clk);
+
+ INIT_LIST_HEAD(&dmac->chan.active_descs);
+
+ of_channels = of_get_child_by_name(pdev->dev.of_node, "adi,channels");
+ if (of_channels == NULL)
+ return -ENODEV;
+
+ for_each_child_of_node(of_channels, of_chan) {
+ ret = axi_dmac_parse_chan_dt(of_chan, &dmac->chan);
+ if (ret) {
+ of_node_put(of_chan);
+ of_node_put(of_channels);
+ return -EINVAL;
+ }
+ }
+ of_node_put(of_channels);
+
+ pdev->dev.dma_parms = &dmac->dma_parms;
+ dma_set_max_seg_size(&pdev->dev, dmac->chan.max_length);
+
+ dma_dev = &dmac->dma_dev;
+ dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
+ dma_cap_set(DMA_CYCLIC, dma_dev->cap_mask);
+ dma_dev->device_free_chan_resources = axi_dmac_free_chan_resources;
+ dma_dev->device_tx_status = dma_cookie_status;
+ dma_dev->device_issue_pending = axi_dmac_issue_pending;
+ dma_dev->device_prep_slave_sg = axi_dmac_prep_slave_sg;
+ dma_dev->device_prep_dma_cyclic = axi_dmac_prep_dma_cyclic;
+ dma_dev->device_prep_interleaved_dma = axi_dmac_prep_interleaved;
+ dma_dev->device_terminate_all = axi_dmac_terminate_all;
+ dma_dev->dev = &pdev->dev;
+ dma_dev->chancnt = 1;
+ dma_dev->src_addr_widths = BIT(dmac->chan.src_width);
+ dma_dev->dst_addr_widths = BIT(dmac->chan.dest_width);
+ dma_dev->directions = BIT(dmac->chan.direction);
+ dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+ INIT_LIST_HEAD(&dma_dev->channels);
+
+ dmac->chan.vchan.desc_free = axi_dmac_desc_free;
+ vchan_init(&dmac->chan.vchan, dma_dev);
+
+ ret = clk_prepare_enable(dmac->clk);
+ if (ret < 0)
+ return ret;
+
+ axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, 0x00);
+
+ ret = dma_async_device_register(dma_dev);
+ if (ret)
+ goto err_clk_disable;
+
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ of_dma_xlate_by_chan_id, dma_dev);
+ if (ret)
+ goto err_unregister_device;
+
+ ret = request_irq(dmac->irq, axi_dmac_interrupt_handler, 0,
+ dev_name(&pdev->dev), dmac);
+ if (ret)
+ goto err_unregister_of;
+
+ platform_set_drvdata(pdev, dmac);
+
+ return 0;
+
+err_unregister_of:
+ of_dma_controller_free(pdev->dev.of_node);
+err_unregister_device:
+ dma_async_device_unregister(&dmac->dma_dev);
+err_clk_disable:
+ clk_disable_unprepare(dmac->clk);
+
+ return ret;
+}
+
+static int axi_dmac_remove(struct platform_device *pdev)
+{
+ struct axi_dmac *dmac = platform_get_drvdata(pdev);
+
+ of_dma_controller_free(pdev->dev.of_node);
+ free_irq(dmac->irq, dmac);
+ tasklet_kill(&dmac->chan.vchan.task);
+ dma_async_device_unregister(&dmac->dma_dev);
+ clk_disable_unprepare(dmac->clk);
+
+ return 0;
+}
+
+static const struct of_device_id axi_dmac_of_match_table[] = {
+ { .compatible = "adi,axi-dmac-1.00.a" },
+ { },
+};
+
+static struct platform_driver axi_dmac_driver = {
+ .driver = {
+ .name = "dma-axi-dmac",
+ .of_match_table = axi_dmac_of_match_table,
+ },
+ .probe = axi_dmac_probe,
+ .remove = axi_dmac_remove,
+};
+module_platform_driver(axi_dmac_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("DMA controller driver for the AXI-DMAC controller");
+MODULE_LICENSE("GPL v2");
git.openpandora.org / pandora-kernel.git / commitdiff