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-rw-r--r--drivers/dma/dw/core.c1319
1 files changed, 1319 insertions, 0 deletions
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
new file mode 100644
index 0000000000..5f7d690e3d
--- /dev/null
+++ b/drivers/dma/dw/core.c
@@ -0,0 +1,1319 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Core driver for the Synopsys DesignWare DMA Controller
+ *
+ * Copyright (C) 2007-2008 Atmel Corporation
+ * Copyright (C) 2010-2011 ST Microelectronics
+ * Copyright (C) 2013 Intel Corporation
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+
+#include "../dmaengine.h"
+#include "internal.h"
+
+/*
+ * This supports the Synopsys "DesignWare AHB Central DMA Controller",
+ * (DW_ahb_dmac) which is used with various AMBA 2.0 systems (not all
+ * of which use ARM any more). See the "Databook" from Synopsys for
+ * information beyond what licensees probably provide.
+ */
+
+/* The set of bus widths supported by the DMA controller */
+#define DW_DMA_BUSWIDTHS \
+ BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
+ BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
+ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
+
+/*----------------------------------------------------------------------*/
+
+static struct device *chan2dev(struct dma_chan *chan)
+{
+ return &chan->dev->device;
+}
+
+static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc)
+{
+ return to_dw_desc(dwc->active_list.next);
+}
+
+static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct dw_desc *desc = txd_to_dw_desc(tx);
+ struct dw_dma_chan *dwc = to_dw_dma_chan(tx->chan);
+ dma_cookie_t cookie;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ cookie = dma_cookie_assign(tx);
+
+ /*
+ * REVISIT: We should attempt to chain as many descriptors as
+ * possible, perhaps even appending to those already submitted
+ * for DMA. But this is hard to do in a race-free manner.
+ */
+
+ list_add_tail(&desc->desc_node, &dwc->queue);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n",
+ __func__, desc->txd.cookie);
+
+ return cookie;
+}
+
+static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ struct dw_desc *desc;
+ dma_addr_t phys;
+
+ desc = dma_pool_zalloc(dw->desc_pool, GFP_ATOMIC, &phys);
+ if (!desc)
+ return NULL;
+
+ dwc->descs_allocated++;
+ INIT_LIST_HEAD(&desc->tx_list);
+ dma_async_tx_descriptor_init(&desc->txd, &dwc->chan);
+ desc->txd.tx_submit = dwc_tx_submit;
+ desc->txd.flags = DMA_CTRL_ACK;
+ desc->txd.phys = phys;
+ return desc;
+}
+
+static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ struct dw_desc *child, *_next;
+
+ if (unlikely(!desc))
+ return;
+
+ list_for_each_entry_safe(child, _next, &desc->tx_list, desc_node) {
+ list_del(&child->desc_node);
+ dma_pool_free(dw->desc_pool, child, child->txd.phys);
+ dwc->descs_allocated--;
+ }
+
+ dma_pool_free(dw->desc_pool, desc, desc->txd.phys);
+ dwc->descs_allocated--;
+}
+
+static void dwc_initialize(struct dw_dma_chan *dwc)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+
+ dw->initialize_chan(dwc);
+
+ /* Enable interrupts */
+ channel_set_bit(dw, MASK.XFER, dwc->mask);
+ channel_set_bit(dw, MASK.ERROR, dwc->mask);
+}
+
+/*----------------------------------------------------------------------*/
+
+static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc)
+{
+ dev_err(chan2dev(&dwc->chan),
+ " SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n",
+ channel_readl(dwc, SAR),
+ channel_readl(dwc, DAR),
+ channel_readl(dwc, LLP),
+ channel_readl(dwc, CTL_HI),
+ channel_readl(dwc, CTL_LO));
+}
+
+static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+ while (dma_readl(dw, CH_EN) & dwc->mask)
+ cpu_relax();
+}
+
+/*----------------------------------------------------------------------*/
+
+/* Perform single block transfer */
+static inline void dwc_do_single_block(struct dw_dma_chan *dwc,
+ struct dw_desc *desc)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ u32 ctllo;
+
+ /*
+ * Software emulation of LLP mode relies on interrupts to continue
+ * multi block transfer.
+ */
+ ctllo = lli_read(desc, ctllo) | DWC_CTLL_INT_EN;
+
+ channel_writel(dwc, SAR, lli_read(desc, sar));
+ channel_writel(dwc, DAR, lli_read(desc, dar));
+ channel_writel(dwc, CTL_LO, ctllo);
+ channel_writel(dwc, CTL_HI, lli_read(desc, ctlhi));
+ channel_set_bit(dw, CH_EN, dwc->mask);
+
+ /* Move pointer to next descriptor */
+ dwc->tx_node_active = dwc->tx_node_active->next;
+}
+
+/* Called with dwc->lock held and bh disabled */
+static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ u8 lms = DWC_LLP_LMS(dwc->dws.m_master);
+ unsigned long was_soft_llp;
+
+ /* ASSERT: channel is idle */
+ if (dma_readl(dw, CH_EN) & dwc->mask) {
+ dev_err(chan2dev(&dwc->chan),
+ "%s: BUG: Attempted to start non-idle channel\n",
+ __func__);
+ dwc_dump_chan_regs(dwc);
+
+ /* The tasklet will hopefully advance the queue... */
+ return;
+ }
+
+ if (dwc->nollp) {
+ was_soft_llp = test_and_set_bit(DW_DMA_IS_SOFT_LLP,
+ &dwc->flags);
+ if (was_soft_llp) {
+ dev_err(chan2dev(&dwc->chan),
+ "BUG: Attempted to start new LLP transfer inside ongoing one\n");
+ return;
+ }
+
+ dwc_initialize(dwc);
+
+ first->residue = first->total_len;
+ dwc->tx_node_active = &first->tx_list;
+
+ /* Submit first block */
+ dwc_do_single_block(dwc, first);
+
+ return;
+ }
+
+ dwc_initialize(dwc);
+
+ channel_writel(dwc, LLP, first->txd.phys | lms);
+ channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
+ channel_writel(dwc, CTL_HI, 0);
+ channel_set_bit(dw, CH_EN, dwc->mask);
+}
+
+static void dwc_dostart_first_queued(struct dw_dma_chan *dwc)
+{
+ struct dw_desc *desc;
+
+ if (list_empty(&dwc->queue))
+ return;
+
+ list_move(dwc->queue.next, &dwc->active_list);
+ desc = dwc_first_active(dwc);
+ dev_vdbg(chan2dev(&dwc->chan), "%s: started %u\n", __func__, desc->txd.cookie);
+ dwc_dostart(dwc, desc);
+}
+
+/*----------------------------------------------------------------------*/
+
+static void
+dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
+ bool callback_required)
+{
+ struct dma_async_tx_descriptor *txd = &desc->txd;
+ struct dw_desc *child;
+ unsigned long flags;
+ struct dmaengine_desc_callback cb;
+
+ dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie);
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ dma_cookie_complete(txd);
+ if (callback_required)
+ dmaengine_desc_get_callback(txd, &cb);
+ else
+ memset(&cb, 0, sizeof(cb));
+
+ /* async_tx_ack */
+ list_for_each_entry(child, &desc->tx_list, desc_node)
+ async_tx_ack(&child->txd);
+ async_tx_ack(&desc->txd);
+ dwc_desc_put(dwc, desc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ dmaengine_desc_callback_invoke(&cb, NULL);
+}
+
+static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ struct dw_desc *desc, *_desc;
+ LIST_HEAD(list);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ if (dma_readl(dw, CH_EN) & dwc->mask) {
+ dev_err(chan2dev(&dwc->chan),
+ "BUG: XFER bit set, but channel not idle!\n");
+
+ /* Try to continue after resetting the channel... */
+ dwc_chan_disable(dw, dwc);
+ }
+
+ /*
+ * Submit queued descriptors ASAP, i.e. before we go through
+ * the completed ones.
+ */
+ list_splice_init(&dwc->active_list, &list);
+ dwc_dostart_first_queued(dwc);
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ list_for_each_entry_safe(desc, _desc, &list, desc_node)
+ dwc_descriptor_complete(dwc, desc, true);
+}
+
+/* Returns how many bytes were already received from source */
+static inline u32 dwc_get_sent(struct dw_dma_chan *dwc)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ u32 ctlhi = channel_readl(dwc, CTL_HI);
+ u32 ctllo = channel_readl(dwc, CTL_LO);
+
+ return dw->block2bytes(dwc, ctlhi, ctllo >> 4 & 7);
+}
+
+static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ dma_addr_t llp;
+ struct dw_desc *desc, *_desc;
+ struct dw_desc *child;
+ u32 status_xfer;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ llp = channel_readl(dwc, LLP);
+ status_xfer = dma_readl(dw, RAW.XFER);
+
+ if (status_xfer & dwc->mask) {
+ /* Everything we've submitted is done */
+ dma_writel(dw, CLEAR.XFER, dwc->mask);
+
+ if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) {
+ struct list_head *head, *active = dwc->tx_node_active;
+
+ /*
+ * We are inside first active descriptor.
+ * Otherwise something is really wrong.
+ */
+ desc = dwc_first_active(dwc);
+
+ head = &desc->tx_list;
+ if (active != head) {
+ /* Update residue to reflect last sent descriptor */
+ if (active == head->next)
+ desc->residue -= desc->len;
+ else
+ desc->residue -= to_dw_desc(active->prev)->len;
+
+ child = to_dw_desc(active);
+
+ /* Submit next block */
+ dwc_do_single_block(dwc, child);
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return;
+ }
+
+ /* We are done here */
+ clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
+ }
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ dwc_complete_all(dw, dwc);
+ return;
+ }
+
+ if (list_empty(&dwc->active_list)) {
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return;
+ }
+
+ if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) {
+ dev_vdbg(chan2dev(&dwc->chan), "%s: soft LLP mode\n", __func__);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return;
+ }
+
+ dev_vdbg(chan2dev(&dwc->chan), "%s: llp=%pad\n", __func__, &llp);
+
+ list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
+ /* Initial residue value */
+ desc->residue = desc->total_len;
+
+ /* Check first descriptors addr */
+ if (desc->txd.phys == DWC_LLP_LOC(llp)) {
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return;
+ }
+
+ /* Check first descriptors llp */
+ if (lli_read(desc, llp) == llp) {
+ /* This one is currently in progress */
+ desc->residue -= dwc_get_sent(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return;
+ }
+
+ desc->residue -= desc->len;
+ list_for_each_entry(child, &desc->tx_list, desc_node) {
+ if (lli_read(child, llp) == llp) {
+ /* Currently in progress */
+ desc->residue -= dwc_get_sent(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return;
+ }
+ desc->residue -= child->len;
+ }
+
+ /*
+ * No descriptors so far seem to be in progress, i.e.
+ * this one must be done.
+ */
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ dwc_descriptor_complete(dwc, desc, true);
+ spin_lock_irqsave(&dwc->lock, flags);
+ }
+
+ dev_err(chan2dev(&dwc->chan),
+ "BUG: All descriptors done, but channel not idle!\n");
+
+ /* Try to continue after resetting the channel... */
+ dwc_chan_disable(dw, dwc);
+
+ dwc_dostart_first_queued(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+}
+
+static inline void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_desc *desc)
+{
+ dev_crit(chan2dev(&dwc->chan), " desc: s0x%x d0x%x l0x%x c0x%x:%x\n",
+ lli_read(desc, sar),
+ lli_read(desc, dar),
+ lli_read(desc, llp),
+ lli_read(desc, ctlhi),
+ lli_read(desc, ctllo));
+}
+
+static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ struct dw_desc *bad_desc;
+ struct dw_desc *child;
+ unsigned long flags;
+
+ dwc_scan_descriptors(dw, dwc);
+
+ spin_lock_irqsave(&dwc->lock, flags);
+
+ /*
+ * The descriptor currently at the head of the active list is
+ * borked. Since we don't have any way to report errors, we'll
+ * just have to scream loudly and try to carry on.
+ */
+ bad_desc = dwc_first_active(dwc);
+ list_del_init(&bad_desc->desc_node);
+ list_move(dwc->queue.next, dwc->active_list.prev);
+
+ /* Clear the error flag and try to restart the controller */
+ dma_writel(dw, CLEAR.ERROR, dwc->mask);
+ if (!list_empty(&dwc->active_list))
+ dwc_dostart(dwc, dwc_first_active(dwc));
+
+ /*
+ * WARN may seem harsh, but since this only happens
+ * when someone submits a bad physical address in a
+ * descriptor, we should consider ourselves lucky that the
+ * controller flagged an error instead of scribbling over
+ * random memory locations.
+ */
+ dev_WARN(chan2dev(&dwc->chan), "Bad descriptor submitted for DMA!\n"
+ " cookie: %d\n", bad_desc->txd.cookie);
+ dwc_dump_lli(dwc, bad_desc);
+ list_for_each_entry(child, &bad_desc->tx_list, desc_node)
+ dwc_dump_lli(dwc, child);
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ /* Pretend the descriptor completed successfully */
+ dwc_descriptor_complete(dwc, bad_desc, true);
+}
+
+static void dw_dma_tasklet(struct tasklet_struct *t)
+{
+ struct dw_dma *dw = from_tasklet(dw, t, tasklet);
+ struct dw_dma_chan *dwc;
+ u32 status_xfer;
+ u32 status_err;
+ unsigned int i;
+
+ status_xfer = dma_readl(dw, RAW.XFER);
+ status_err = dma_readl(dw, RAW.ERROR);
+
+ dev_vdbg(dw->dma.dev, "%s: status_err=%x\n", __func__, status_err);
+
+ for (i = 0; i < dw->dma.chancnt; i++) {
+ dwc = &dw->chan[i];
+ if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags))
+ dev_vdbg(dw->dma.dev, "Cyclic xfer is not implemented\n");
+ else if (status_err & (1 << i))
+ dwc_handle_error(dw, dwc);
+ else if (status_xfer & (1 << i))
+ dwc_scan_descriptors(dw, dwc);
+ }
+
+ /* Re-enable interrupts */
+ channel_set_bit(dw, MASK.XFER, dw->all_chan_mask);
+ channel_set_bit(dw, MASK.ERROR, dw->all_chan_mask);
+}
+
+static irqreturn_t dw_dma_interrupt(int irq, void *dev_id)
+{
+ struct dw_dma *dw = dev_id;
+ u32 status;
+
+ /* Check if we have any interrupt from the DMAC which is not in use */
+ if (!dw->in_use)
+ return IRQ_NONE;
+
+ status = dma_readl(dw, STATUS_INT);
+ dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__, status);
+
+ /* Check if we have any interrupt from the DMAC */
+ if (!status)
+ return IRQ_NONE;
+
+ /*
+ * Just disable the interrupts. We'll turn them back on in the
+ * softirq handler.
+ */
+ channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
+ channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
+ channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);
+
+ status = dma_readl(dw, STATUS_INT);
+ if (status) {
+ dev_err(dw->dma.dev,
+ "BUG: Unexpected interrupts pending: 0x%x\n",
+ status);
+
+ /* Try to recover */
+ channel_clear_bit(dw, MASK.XFER, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK.BLOCK, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK.SRC_TRAN, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK.DST_TRAN, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK.ERROR, (1 << 8) - 1);
+ }
+
+ tasklet_schedule(&dw->tasklet);
+
+ return IRQ_HANDLED;
+}
+
+/*----------------------------------------------------------------------*/
+
+static struct dma_async_tx_descriptor *
+dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+ struct dw_desc *desc;
+ struct dw_desc *first;
+ struct dw_desc *prev;
+ size_t xfer_count;
+ size_t offset;
+ u8 m_master = dwc->dws.m_master;
+ unsigned int src_width;
+ unsigned int dst_width;
+ unsigned int data_width = dw->pdata->data_width[m_master];
+ u32 ctllo, ctlhi;
+ u8 lms = DWC_LLP_LMS(m_master);
+
+ dev_vdbg(chan2dev(chan),
+ "%s: d%pad s%pad l0x%zx f0x%lx\n", __func__,
+ &dest, &src, len, flags);
+
+ if (unlikely(!len)) {
+ dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__);
+ return NULL;
+ }
+
+ dwc->direction = DMA_MEM_TO_MEM;
+
+ src_width = dst_width = __ffs(data_width | src | dest | len);
+
+ ctllo = dw->prepare_ctllo(dwc)
+ | DWC_CTLL_DST_WIDTH(dst_width)
+ | DWC_CTLL_SRC_WIDTH(src_width)
+ | DWC_CTLL_DST_INC
+ | DWC_CTLL_SRC_INC
+ | DWC_CTLL_FC_M2M;
+ prev = first = NULL;
+
+ for (offset = 0; offset < len; offset += xfer_count) {
+ desc = dwc_desc_get(dwc);
+ if (!desc)
+ goto err_desc_get;
+
+ ctlhi = dw->bytes2block(dwc, len - offset, src_width, &xfer_count);
+
+ lli_write(desc, sar, src + offset);
+ lli_write(desc, dar, dest + offset);
+ lli_write(desc, ctllo, ctllo);
+ lli_write(desc, ctlhi, ctlhi);
+ desc->len = xfer_count;
+
+ if (!first) {
+ first = desc;
+ } else {
+ lli_write(prev, llp, desc->txd.phys | lms);
+ list_add_tail(&desc->desc_node, &first->tx_list);
+ }
+ prev = desc;
+ }
+
+ if (flags & DMA_PREP_INTERRUPT)
+ /* Trigger interrupt after last block */
+ lli_set(prev, ctllo, DWC_CTLL_INT_EN);
+
+ prev->lli.llp = 0;
+ lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
+ first->txd.flags = flags;
+ first->total_len = len;
+
+ return &first->txd;
+
+err_desc_get:
+ dwc_desc_put(dwc, first);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+dwc_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 dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+ struct dma_slave_config *sconfig = &dwc->dma_sconfig;
+ struct dw_desc *prev;
+ struct dw_desc *first;
+ u32 ctllo, ctlhi;
+ u8 m_master = dwc->dws.m_master;
+ u8 lms = DWC_LLP_LMS(m_master);
+ dma_addr_t reg;
+ unsigned int reg_width;
+ unsigned int mem_width;
+ unsigned int data_width = dw->pdata->data_width[m_master];
+ unsigned int i;
+ struct scatterlist *sg;
+ size_t total_len = 0;
+
+ dev_vdbg(chan2dev(chan), "%s\n", __func__);
+
+ if (unlikely(!is_slave_direction(direction) || !sg_len))
+ return NULL;
+
+ dwc->direction = direction;
+
+ prev = first = NULL;
+
+ switch (direction) {
+ case DMA_MEM_TO_DEV:
+ reg_width = __ffs(sconfig->dst_addr_width);
+ reg = sconfig->dst_addr;
+ ctllo = dw->prepare_ctllo(dwc)
+ | DWC_CTLL_DST_WIDTH(reg_width)
+ | DWC_CTLL_DST_FIX
+ | DWC_CTLL_SRC_INC;
+
+ ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) :
+ DWC_CTLL_FC(DW_DMA_FC_D_M2P);
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ struct dw_desc *desc;
+ u32 len, mem;
+ size_t dlen;
+
+ mem = sg_dma_address(sg);
+ len = sg_dma_len(sg);
+
+ mem_width = __ffs(data_width | mem | len);
+
+slave_sg_todev_fill_desc:
+ desc = dwc_desc_get(dwc);
+ if (!desc)
+ goto err_desc_get;
+
+ ctlhi = dw->bytes2block(dwc, len, mem_width, &dlen);
+
+ lli_write(desc, sar, mem);
+ lli_write(desc, dar, reg);
+ lli_write(desc, ctlhi, ctlhi);
+ lli_write(desc, ctllo, ctllo | DWC_CTLL_SRC_WIDTH(mem_width));
+ desc->len = dlen;
+
+ if (!first) {
+ first = desc;
+ } else {
+ lli_write(prev, llp, desc->txd.phys | lms);
+ list_add_tail(&desc->desc_node, &first->tx_list);
+ }
+ prev = desc;
+
+ mem += dlen;
+ len -= dlen;
+ total_len += dlen;
+
+ if (len)
+ goto slave_sg_todev_fill_desc;
+ }
+ break;
+ case DMA_DEV_TO_MEM:
+ reg_width = __ffs(sconfig->src_addr_width);
+ reg = sconfig->src_addr;
+ ctllo = dw->prepare_ctllo(dwc)
+ | DWC_CTLL_SRC_WIDTH(reg_width)
+ | DWC_CTLL_DST_INC
+ | DWC_CTLL_SRC_FIX;
+
+ ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) :
+ DWC_CTLL_FC(DW_DMA_FC_D_P2M);
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ struct dw_desc *desc;
+ u32 len, mem;
+ size_t dlen;
+
+ mem = sg_dma_address(sg);
+ len = sg_dma_len(sg);
+
+slave_sg_fromdev_fill_desc:
+ desc = dwc_desc_get(dwc);
+ if (!desc)
+ goto err_desc_get;
+
+ ctlhi = dw->bytes2block(dwc, len, reg_width, &dlen);
+
+ lli_write(desc, sar, reg);
+ lli_write(desc, dar, mem);
+ lli_write(desc, ctlhi, ctlhi);
+ mem_width = __ffs(data_width | mem);
+ lli_write(desc, ctllo, ctllo | DWC_CTLL_DST_WIDTH(mem_width));
+ desc->len = dlen;
+
+ if (!first) {
+ first = desc;
+ } else {
+ lli_write(prev, llp, desc->txd.phys | lms);
+ list_add_tail(&desc->desc_node, &first->tx_list);
+ }
+ prev = desc;
+
+ mem += dlen;
+ len -= dlen;
+ total_len += dlen;
+
+ if (len)
+ goto slave_sg_fromdev_fill_desc;
+ }
+ break;
+ default:
+ return NULL;
+ }
+
+ if (flags & DMA_PREP_INTERRUPT)
+ /* Trigger interrupt after last block */
+ lli_set(prev, ctllo, DWC_CTLL_INT_EN);
+
+ prev->lli.llp = 0;
+ lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
+ first->total_len = total_len;
+
+ return &first->txd;
+
+err_desc_get:
+ dev_err(chan2dev(chan),
+ "not enough descriptors available. Direction %d\n", direction);
+ dwc_desc_put(dwc, first);
+ return NULL;
+}
+
+bool dw_dma_filter(struct dma_chan *chan, void *param)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma_slave *dws = param;
+
+ if (dws->dma_dev != chan->device->dev)
+ return false;
+
+ /* permit channels in accordance with the channels mask */
+ if (dws->channels && !(dws->channels & dwc->mask))
+ return false;
+
+ /* We have to copy data since dws can be temporary storage */
+ memcpy(&dwc->dws, dws, sizeof(struct dw_dma_slave));
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(dw_dma_filter);
+
+static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+
+ memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
+
+ dwc->dma_sconfig.src_maxburst =
+ clamp(dwc->dma_sconfig.src_maxburst, 0U, dwc->max_burst);
+ dwc->dma_sconfig.dst_maxburst =
+ clamp(dwc->dma_sconfig.dst_maxburst, 0U, dwc->max_burst);
+
+ dw->encode_maxburst(dwc, &dwc->dma_sconfig.src_maxburst);
+ dw->encode_maxburst(dwc, &dwc->dma_sconfig.dst_maxburst);
+
+ return 0;
+}
+
+static void dwc_chan_pause(struct dw_dma_chan *dwc, bool drain)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ unsigned int count = 20; /* timeout iterations */
+
+ dw->suspend_chan(dwc, drain);
+
+ while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--)
+ udelay(2);
+
+ set_bit(DW_DMA_IS_PAUSED, &dwc->flags);
+}
+
+static int dwc_pause(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ dwc_chan_pause(dwc, false);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ return 0;
+}
+
+static inline void dwc_chan_resume(struct dw_dma_chan *dwc, bool drain)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+
+ dw->resume_chan(dwc, drain);
+
+ clear_bit(DW_DMA_IS_PAUSED, &dwc->flags);
+}
+
+static int dwc_resume(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+
+ if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags))
+ dwc_chan_resume(dwc, false);
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ return 0;
+}
+
+static int dwc_terminate_all(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+ struct dw_desc *desc, *_desc;
+ unsigned long flags;
+ LIST_HEAD(list);
+
+ spin_lock_irqsave(&dwc->lock, flags);
+
+ clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
+
+ dwc_chan_pause(dwc, true);
+
+ dwc_chan_disable(dw, dwc);
+
+ dwc_chan_resume(dwc, true);
+
+ /* active_list entries will end up before queued entries */
+ list_splice_init(&dwc->queue, &list);
+ list_splice_init(&dwc->active_list, &list);
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ /* Flush all pending and queued descriptors */
+ list_for_each_entry_safe(desc, _desc, &list, desc_node)
+ dwc_descriptor_complete(dwc, desc, false);
+
+ return 0;
+}
+
+static struct dw_desc *dwc_find_desc(struct dw_dma_chan *dwc, dma_cookie_t c)
+{
+ struct dw_desc *desc;
+
+ list_for_each_entry(desc, &dwc->active_list, desc_node)
+ if (desc->txd.cookie == c)
+ return desc;
+
+ return NULL;
+}
+
+static u32 dwc_get_residue_and_status(struct dw_dma_chan *dwc, dma_cookie_t cookie,
+ enum dma_status *status)
+{
+ struct dw_desc *desc;
+ unsigned long flags;
+ u32 residue;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+
+ desc = dwc_find_desc(dwc, cookie);
+ if (desc) {
+ if (desc == dwc_first_active(dwc)) {
+ residue = desc->residue;
+ if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue)
+ residue -= dwc_get_sent(dwc);
+ if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags))
+ *status = DMA_PAUSED;
+ } else {
+ residue = desc->total_len;
+ }
+ } else {
+ residue = 0;
+ }
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+ return residue;
+}
+
+static enum dma_status
+dwc_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ enum dma_status ret;
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ dma_set_residue(txstate, dwc_get_residue_and_status(dwc, cookie, &ret));
+ return ret;
+}
+
+static void dwc_issue_pending(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dwc->lock, flags);
+ if (list_empty(&dwc->active_list))
+ dwc_dostart_first_queued(dwc);
+ spin_unlock_irqrestore(&dwc->lock, flags);
+}
+
+/*----------------------------------------------------------------------*/
+
+void do_dw_dma_off(struct dw_dma *dw)
+{
+ dma_writel(dw, CFG, 0);
+
+ channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
+ channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
+ channel_clear_bit(dw, MASK.SRC_TRAN, dw->all_chan_mask);
+ channel_clear_bit(dw, MASK.DST_TRAN, dw->all_chan_mask);
+ channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);
+
+ while (dma_readl(dw, CFG) & DW_CFG_DMA_EN)
+ cpu_relax();
+}
+
+void do_dw_dma_on(struct dw_dma *dw)
+{
+ dma_writel(dw, CFG, DW_CFG_DMA_EN);
+}
+
+static int dwc_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+
+ dev_vdbg(chan2dev(chan), "%s\n", __func__);
+
+ /* ASSERT: channel is idle */
+ if (dma_readl(dw, CH_EN) & dwc->mask) {
+ dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
+ return -EIO;
+ }
+
+ dma_cookie_init(chan);
+
+ /*
+ * NOTE: some controllers may have additional features that we
+ * need to initialize here, like "scatter-gather" (which
+ * doesn't mean what you think it means), and status writeback.
+ */
+
+ /*
+ * We need controller-specific data to set up slave transfers.
+ */
+ if (chan->private && !dw_dma_filter(chan, chan->private)) {
+ dev_warn(chan2dev(chan), "Wrong controller-specific data\n");
+ return -EINVAL;
+ }
+
+ /* Enable controller here if needed */
+ if (!dw->in_use)
+ do_dw_dma_on(dw);
+ dw->in_use |= dwc->mask;
+
+ return 0;
+}
+
+static void dwc_free_chan_resources(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+ unsigned long flags;
+
+ dev_dbg(chan2dev(chan), "%s: descs allocated=%u\n", __func__,
+ dwc->descs_allocated);
+
+ /* ASSERT: channel is idle */
+ BUG_ON(!list_empty(&dwc->active_list));
+ BUG_ON(!list_empty(&dwc->queue));
+ BUG_ON(dma_readl(to_dw_dma(chan->device), CH_EN) & dwc->mask);
+
+ spin_lock_irqsave(&dwc->lock, flags);
+
+ /* Clear custom channel configuration */
+ memset(&dwc->dws, 0, sizeof(struct dw_dma_slave));
+
+ /* Disable interrupts */
+ channel_clear_bit(dw, MASK.XFER, dwc->mask);
+ channel_clear_bit(dw, MASK.BLOCK, dwc->mask);
+ channel_clear_bit(dw, MASK.ERROR, dwc->mask);
+
+ spin_unlock_irqrestore(&dwc->lock, flags);
+
+ /* Disable controller in case it was a last user */
+ dw->in_use &= ~dwc->mask;
+ if (!dw->in_use)
+ do_dw_dma_off(dw);
+
+ dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
+}
+
+static void dwc_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+
+ caps->max_burst = dwc->max_burst;
+
+ /*
+ * It might be crucial for some devices to have the hardware
+ * accelerated multi-block transfers supported, aka LLPs in DW DMAC
+ * notation. So if LLPs are supported then max_sg_burst is set to
+ * zero which means unlimited number of SG entries can be handled in a
+ * single DMA transaction, otherwise it's just one SG entry.
+ */
+ if (dwc->nollp)
+ caps->max_sg_burst = 1;
+ else
+ caps->max_sg_burst = 0;
+}
+
+int do_dma_probe(struct dw_dma_chip *chip)
+{
+ struct dw_dma *dw = chip->dw;
+ struct dw_dma_platform_data *pdata;
+ bool autocfg = false;
+ unsigned int dw_params;
+ unsigned int i;
+ int err;
+
+ dw->pdata = devm_kzalloc(chip->dev, sizeof(*dw->pdata), GFP_KERNEL);
+ if (!dw->pdata)
+ return -ENOMEM;
+
+ dw->regs = chip->regs;
+
+ pm_runtime_get_sync(chip->dev);
+
+ if (!chip->pdata) {
+ dw_params = dma_readl(dw, DW_PARAMS);
+ dev_dbg(chip->dev, "DW_PARAMS: 0x%08x\n", dw_params);
+
+ autocfg = dw_params >> DW_PARAMS_EN & 1;
+ if (!autocfg) {
+ err = -EINVAL;
+ goto err_pdata;
+ }
+
+ /* Reassign the platform data pointer */
+ pdata = dw->pdata;
+
+ /* Get hardware configuration parameters */
+ pdata->nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 7) + 1;
+ pdata->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1;
+ for (i = 0; i < pdata->nr_masters; i++) {
+ pdata->data_width[i] =
+ 4 << (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3);
+ }
+ pdata->block_size = dma_readl(dw, MAX_BLK_SIZE);
+
+ /* Fill platform data with the default values */
+ pdata->chan_allocation_order = CHAN_ALLOCATION_ASCENDING;
+ pdata->chan_priority = CHAN_PRIORITY_ASCENDING;
+ } else if (chip->pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS) {
+ err = -EINVAL;
+ goto err_pdata;
+ } else {
+ memcpy(dw->pdata, chip->pdata, sizeof(*dw->pdata));
+
+ /* Reassign the platform data pointer */
+ pdata = dw->pdata;
+ }
+
+ dw->chan = devm_kcalloc(chip->dev, pdata->nr_channels, sizeof(*dw->chan),
+ GFP_KERNEL);
+ if (!dw->chan) {
+ err = -ENOMEM;
+ goto err_pdata;
+ }
+
+ /* Calculate all channel mask before DMA setup */
+ dw->all_chan_mask = (1 << pdata->nr_channels) - 1;
+
+ /* Force dma off, just in case */
+ dw->disable(dw);
+
+ /* Device and instance ID for IRQ and DMA pool */
+ dw->set_device_name(dw, chip->id);
+
+ /* Create a pool of consistent memory blocks for hardware descriptors */
+ dw->desc_pool = dmam_pool_create(dw->name, chip->dev,
+ sizeof(struct dw_desc), 4, 0);
+ if (!dw->desc_pool) {
+ dev_err(chip->dev, "No memory for descriptors dma pool\n");
+ err = -ENOMEM;
+ goto err_pdata;
+ }
+
+ tasklet_setup(&dw->tasklet, dw_dma_tasklet);
+
+ err = request_irq(chip->irq, dw_dma_interrupt, IRQF_SHARED,
+ dw->name, dw);
+ if (err)
+ goto err_pdata;
+
+ INIT_LIST_HEAD(&dw->dma.channels);
+ for (i = 0; i < pdata->nr_channels; i++) {
+ struct dw_dma_chan *dwc = &dw->chan[i];
+
+ dwc->chan.device = &dw->dma;
+ dma_cookie_init(&dwc->chan);
+ if (pdata->chan_allocation_order == CHAN_ALLOCATION_ASCENDING)
+ list_add_tail(&dwc->chan.device_node,
+ &dw->dma.channels);
+ else
+ list_add(&dwc->chan.device_node, &dw->dma.channels);
+
+ /* 7 is highest priority & 0 is lowest. */
+ if (pdata->chan_priority == CHAN_PRIORITY_ASCENDING)
+ dwc->priority = pdata->nr_channels - i - 1;
+ else
+ dwc->priority = i;
+
+ dwc->ch_regs = &__dw_regs(dw)->CHAN[i];
+ spin_lock_init(&dwc->lock);
+ dwc->mask = 1 << i;
+
+ INIT_LIST_HEAD(&dwc->active_list);
+ INIT_LIST_HEAD(&dwc->queue);
+
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+
+ dwc->direction = DMA_TRANS_NONE;
+
+ /* Hardware configuration */
+ if (autocfg) {
+ unsigned int r = DW_DMA_MAX_NR_CHANNELS - i - 1;
+ void __iomem *addr = &__dw_regs(dw)->DWC_PARAMS[r];
+ unsigned int dwc_params = readl(addr);
+
+ dev_dbg(chip->dev, "DWC_PARAMS[%d]: 0x%08x\n", i,
+ dwc_params);
+
+ /*
+ * Decode maximum block size for given channel. The
+ * stored 4 bit value represents blocks from 0x00 for 3
+ * up to 0x0a for 4095.
+ */
+ dwc->block_size =
+ (4 << ((pdata->block_size >> 4 * i) & 0xf)) - 1;
+
+ /*
+ * According to the DW DMA databook the true scatter-
+ * gether LLPs aren't available if either multi-block
+ * config is disabled (CHx_MULTI_BLK_EN == 0) or the
+ * LLP register is hard-coded to zeros
+ * (CHx_HC_LLP == 1).
+ */
+ dwc->nollp =
+ (dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0 ||
+ (dwc_params >> DWC_PARAMS_HC_LLP & 0x1) == 1;
+ dwc->max_burst =
+ (0x4 << (dwc_params >> DWC_PARAMS_MSIZE & 0x7));
+ } else {
+ dwc->block_size = pdata->block_size;
+ dwc->nollp = !pdata->multi_block[i];
+ dwc->max_burst = pdata->max_burst[i] ?: DW_DMA_MAX_BURST;
+ }
+ }
+
+ /* Clear all interrupts on all channels. */
+ dma_writel(dw, CLEAR.XFER, dw->all_chan_mask);
+ dma_writel(dw, CLEAR.BLOCK, dw->all_chan_mask);
+ dma_writel(dw, CLEAR.SRC_TRAN, dw->all_chan_mask);
+ dma_writel(dw, CLEAR.DST_TRAN, dw->all_chan_mask);
+ dma_writel(dw, CLEAR.ERROR, dw->all_chan_mask);
+
+ /* Set capabilities */
+ dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
+ dma_cap_set(DMA_PRIVATE, dw->dma.cap_mask);
+ dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
+
+ dw->dma.dev = chip->dev;
+ dw->dma.device_alloc_chan_resources = dwc_alloc_chan_resources;
+ dw->dma.device_free_chan_resources = dwc_free_chan_resources;
+
+ dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy;
+ dw->dma.device_prep_slave_sg = dwc_prep_slave_sg;
+
+ dw->dma.device_caps = dwc_caps;
+ dw->dma.device_config = dwc_config;
+ dw->dma.device_pause = dwc_pause;
+ dw->dma.device_resume = dwc_resume;
+ dw->dma.device_terminate_all = dwc_terminate_all;
+
+ dw->dma.device_tx_status = dwc_tx_status;
+ dw->dma.device_issue_pending = dwc_issue_pending;
+
+ /* DMA capabilities */
+ dw->dma.min_burst = DW_DMA_MIN_BURST;
+ dw->dma.max_burst = DW_DMA_MAX_BURST;
+ dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS;
+ dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS;
+ dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) |
+ BIT(DMA_MEM_TO_MEM);
+ dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+ /*
+ * For now there is no hardware with non uniform maximum block size
+ * across all of the device channels, so we set the maximum segment
+ * size as the block size found for the very first channel.
+ */
+ dma_set_max_seg_size(dw->dma.dev, dw->chan[0].block_size);
+
+ err = dma_async_device_register(&dw->dma);
+ if (err)
+ goto err_dma_register;
+
+ dev_info(chip->dev, "DesignWare DMA Controller, %d channels\n",
+ pdata->nr_channels);
+
+ pm_runtime_put_sync_suspend(chip->dev);
+
+ return 0;
+
+err_dma_register:
+ free_irq(chip->irq, dw);
+err_pdata:
+ pm_runtime_put_sync_suspend(chip->dev);
+ return err;
+}
+
+int do_dma_remove(struct dw_dma_chip *chip)
+{
+ struct dw_dma *dw = chip->dw;
+ struct dw_dma_chan *dwc, *_dwc;
+
+ pm_runtime_get_sync(chip->dev);
+
+ do_dw_dma_off(dw);
+ dma_async_device_unregister(&dw->dma);
+
+ free_irq(chip->irq, dw);
+ tasklet_kill(&dw->tasklet);
+
+ list_for_each_entry_safe(dwc, _dwc, &dw->dma.channels,
+ chan.device_node) {
+ list_del(&dwc->chan.device_node);
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+ }
+
+ pm_runtime_put_sync_suspend(chip->dev);
+ return 0;
+}
+
+int do_dw_dma_disable(struct dw_dma_chip *chip)
+{
+ struct dw_dma *dw = chip->dw;
+
+ dw->disable(dw);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(do_dw_dma_disable);
+
+int do_dw_dma_enable(struct dw_dma_chip *chip)
+{
+ struct dw_dma *dw = chip->dw;
+
+ dw->enable(dw);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(do_dw_dma_enable);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller core driver");
+MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
+MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");