Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 708 insertions, 0 deletions

diff --git a/drivers/dma/idma64.c b/drivers/dma/idma64.c
new file mode 100644
index 000000000..5fcd1befc
--- /dev/null
+++ b/drivers/dma/idma64.c
@@ -0,0 +1,708 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Core driver for the Intel integrated DMA 64-bit
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <linux/dma/idma64.h>
+
+#include "idma64.h"
+
+/* For now we support only two channels */
+#define IDMA64_NR_CHAN		2
+
+/* ---------------------------------------------------------------------- */
+
+static struct device *chan2dev(struct dma_chan *chan)
+{
+	return &chan->dev->device;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static void idma64_off(struct idma64 *idma64)
+{
+	unsigned short count = 100;
+
+	dma_writel(idma64, CFG, 0);
+
+	channel_clear_bit(idma64, MASK(XFER), idma64->all_chan_mask);
+	channel_clear_bit(idma64, MASK(BLOCK), idma64->all_chan_mask);
+	channel_clear_bit(idma64, MASK(SRC_TRAN), idma64->all_chan_mask);
+	channel_clear_bit(idma64, MASK(DST_TRAN), idma64->all_chan_mask);
+	channel_clear_bit(idma64, MASK(ERROR), idma64->all_chan_mask);
+
+	do {
+		cpu_relax();
+	} while (dma_readl(idma64, CFG) & IDMA64_CFG_DMA_EN && --count);
+}
+
+static void idma64_on(struct idma64 *idma64)
+{
+	dma_writel(idma64, CFG, IDMA64_CFG_DMA_EN);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static void idma64_chan_init(struct idma64 *idma64, struct idma64_chan *idma64c)
+{
+	u32 cfghi = IDMA64C_CFGH_SRC_PER(1) | IDMA64C_CFGH_DST_PER(0);
+	u32 cfglo = 0;
+
+	/* Set default burst alignment */
+	cfglo |= IDMA64C_CFGL_DST_BURST_ALIGN | IDMA64C_CFGL_SRC_BURST_ALIGN;
+
+	channel_writel(idma64c, CFG_LO, cfglo);
+	channel_writel(idma64c, CFG_HI, cfghi);
+
+	/* Enable interrupts */
+	channel_set_bit(idma64, MASK(XFER), idma64c->mask);
+	channel_set_bit(idma64, MASK(ERROR), idma64c->mask);
+
+	/*
+	 * Enforce the controller to be turned on.
+	 *
+	 * The iDMA is turned off in ->probe() and looses context during system
+	 * suspend / resume cycle. That's why we have to enable it each time we
+	 * use it.
+	 */
+	idma64_on(idma64);
+}
+
+static void idma64_chan_stop(struct idma64 *idma64, struct idma64_chan *idma64c)
+{
+	channel_clear_bit(idma64, CH_EN, idma64c->mask);
+}
+
+static void idma64_chan_start(struct idma64 *idma64, struct idma64_chan *idma64c)
+{
+	struct idma64_desc *desc = idma64c->desc;
+	struct idma64_hw_desc *hw = &desc->hw[0];
+
+	channel_writeq(idma64c, SAR, 0);
+	channel_writeq(idma64c, DAR, 0);
+
+	channel_writel(idma64c, CTL_HI, IDMA64C_CTLH_BLOCK_TS(~0UL));
+	channel_writel(idma64c, CTL_LO, IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
+
+	channel_writeq(idma64c, LLP, hw->llp);
+
+	channel_set_bit(idma64, CH_EN, idma64c->mask);
+}
+
+static void idma64_stop_transfer(struct idma64_chan *idma64c)
+{
+	struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
+
+	idma64_chan_stop(idma64, idma64c);
+}
+
+static void idma64_start_transfer(struct idma64_chan *idma64c)
+{
+	struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
+	struct virt_dma_desc *vdesc;
+
+	/* Get the next descriptor */
+	vdesc = vchan_next_desc(&idma64c->vchan);
+	if (!vdesc) {
+		idma64c->desc = NULL;
+		return;
+	}
+
+	list_del(&vdesc->node);
+	idma64c->desc = to_idma64_desc(vdesc);
+
+	/* Configure the channel */
+	idma64_chan_init(idma64, idma64c);
+
+	/* Start the channel with a new descriptor */
+	idma64_chan_start(idma64, idma64c);
+}
+
+/* ---------------------------------------------------------------------- */
+
+static void idma64_chan_irq(struct idma64 *idma64, unsigned short c,
+		u32 status_err, u32 status_xfer)
+{
+	struct idma64_chan *idma64c = &idma64->chan[c];
+	struct dma_chan_percpu *stat;
+	struct idma64_desc *desc;
+
+	stat = this_cpu_ptr(idma64c->vchan.chan.local);
+
+	spin_lock(&idma64c->vchan.lock);
+	desc = idma64c->desc;
+	if (desc) {
+		if (status_err & (1 << c)) {
+			dma_writel(idma64, CLEAR(ERROR), idma64c->mask);
+			desc->status = DMA_ERROR;
+		} else if (status_xfer & (1 << c)) {
+			dma_writel(idma64, CLEAR(XFER), idma64c->mask);
+			desc->status = DMA_COMPLETE;
+			vchan_cookie_complete(&desc->vdesc);
+			stat->bytes_transferred += desc->length;
+			idma64_start_transfer(idma64c);
+		}
+
+		/* idma64_start_transfer() updates idma64c->desc */
+		if (idma64c->desc == NULL || desc->status == DMA_ERROR)
+			idma64_stop_transfer(idma64c);
+	}
+	spin_unlock(&idma64c->vchan.lock);
+}
+
+static irqreturn_t idma64_irq(int irq, void *dev)
+{
+	struct idma64 *idma64 = dev;
+	u32 status = dma_readl(idma64, STATUS_INT);
+	u32 status_xfer;
+	u32 status_err;
+	unsigned short i;
+
+	/* Since IRQ may be shared, check if DMA controller is powered on */
+	if (status == GENMASK(31, 0))
+		return IRQ_NONE;
+
+	dev_vdbg(idma64->dma.dev, "%s: status=%#x\n", __func__, status);
+
+	/* Check if we have any interrupt from the DMA controller */
+	if (!status)
+		return IRQ_NONE;
+
+	status_xfer = dma_readl(idma64, RAW(XFER));
+	status_err = dma_readl(idma64, RAW(ERROR));
+
+	for (i = 0; i < idma64->dma.chancnt; i++)
+		idma64_chan_irq(idma64, i, status_err, status_xfer);
+
+	return IRQ_HANDLED;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
+{
+	struct idma64_desc *desc;
+
+	desc = kzalloc_obj(*desc, GFP_NOWAIT);
+	if (!desc)
+		return NULL;
+
+	desc->hw = kzalloc_objs(*desc->hw, ndesc, GFP_NOWAIT);
+	if (!desc->hw) {
+		kfree(desc);
+		return NULL;
+	}
+
+	return desc;
+}
+
+static void idma64_desc_free(struct idma64_chan *idma64c,
+		struct idma64_desc *desc)
+{
+	struct idma64_hw_desc *hw;
+
+	if (desc->ndesc) {
+		unsigned int i = desc->ndesc;
+
+		do {
+			hw = &desc->hw[--i];
+			dma_pool_free(idma64c->pool, hw->lli, hw->llp);
+		} while (i);
+	}
+
+	kfree(desc->hw);
+	kfree(desc);
+}
+
+static void idma64_vdesc_free(struct virt_dma_desc *vdesc)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(vdesc->tx.chan);
+
+	idma64_desc_free(idma64c, to_idma64_desc(vdesc));
+}
+
+static void idma64_hw_desc_fill(struct idma64_hw_desc *hw,
+		struct dma_slave_config *config,
+		enum dma_transfer_direction direction, u64 llp)
+{
+	struct idma64_lli *lli = hw->lli;
+	u64 sar, dar;
+	u32 ctlhi = IDMA64C_CTLH_BLOCK_TS(hw->len);
+	u32 ctllo = IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN;
+	u32 src_width, dst_width;
+
+	if (direction == DMA_MEM_TO_DEV) {
+		sar = hw->phys;
+		dar = config->dst_addr;
+		ctllo |= IDMA64C_CTLL_DST_FIX | IDMA64C_CTLL_SRC_INC |
+			 IDMA64C_CTLL_FC_M2P;
+		src_width = __ffs(sar | hw->len | 4);
+		dst_width = __ffs(config->dst_addr_width);
+	} else {	/* DMA_DEV_TO_MEM */
+		sar = config->src_addr;
+		dar = hw->phys;
+		ctllo |= IDMA64C_CTLL_DST_INC | IDMA64C_CTLL_SRC_FIX |
+			 IDMA64C_CTLL_FC_P2M;
+		src_width = __ffs(config->src_addr_width);
+		dst_width = __ffs(dar | hw->len | 4);
+	}
+
+	lli->sar = sar;
+	lli->dar = dar;
+
+	lli->ctlhi = ctlhi;
+	lli->ctllo = ctllo |
+		     IDMA64C_CTLL_SRC_MSIZE(config->src_maxburst) |
+		     IDMA64C_CTLL_DST_MSIZE(config->dst_maxburst) |
+		     IDMA64C_CTLL_DST_WIDTH(dst_width) |
+		     IDMA64C_CTLL_SRC_WIDTH(src_width);
+
+	lli->llp = llp;
+}
+
+static void idma64_desc_fill(struct idma64_chan *idma64c,
+		struct idma64_desc *desc)
+{
+	struct dma_slave_config *config = &idma64c->config;
+	unsigned int i = desc->ndesc;
+	struct idma64_hw_desc *hw = &desc->hw[i - 1];
+	struct idma64_lli *lli = hw->lli;
+	u64 llp = 0;
+
+	/* Fill the hardware descriptors and link them to a list */
+	do {
+		hw = &desc->hw[--i];
+		idma64_hw_desc_fill(hw, config, desc->direction, llp);
+		llp = hw->llp;
+		desc->length += hw->len;
+	} while (i);
+
+	/* Trigger an interrupt after the last block is transferred */
+	lli->ctllo |= IDMA64C_CTLL_INT_EN;
+
+	/* Disable LLP transfer in the last block */
+	lli->ctllo &= ~(IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
+}
+
+static struct dma_async_tx_descriptor *idma64_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 idma64_chan *idma64c = to_idma64_chan(chan);
+	struct idma64_desc *desc;
+	struct scatterlist *sg;
+	unsigned int i;
+
+	desc = idma64_alloc_desc(sg_len);
+	if (!desc)
+		return NULL;
+
+	for_each_sg(sgl, sg, sg_len, i) {
+		struct idma64_hw_desc *hw = &desc->hw[i];
+
+		/* Allocate DMA capable memory for hardware descriptor */
+		hw->lli = dma_pool_alloc(idma64c->pool, GFP_NOWAIT, &hw->llp);
+		if (!hw->lli) {
+			desc->ndesc = i;
+			idma64_desc_free(idma64c, desc);
+			return NULL;
+		}
+
+		hw->phys = sg_dma_address(sg);
+		hw->len = sg_dma_len(sg);
+	}
+
+	desc->ndesc = sg_len;
+	desc->direction = direction;
+	desc->status = DMA_IN_PROGRESS;
+
+	idma64_desc_fill(idma64c, desc);
+	return vchan_tx_prep(&idma64c->vchan, &desc->vdesc, flags);
+}
+
+static void idma64_issue_pending(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&idma64c->vchan.lock, flags);
+	if (vchan_issue_pending(&idma64c->vchan) && !idma64c->desc)
+		idma64_start_transfer(idma64c);
+	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
+}
+
+static size_t idma64_active_desc_size(struct idma64_chan *idma64c)
+{
+	struct idma64_desc *desc = idma64c->desc;
+	struct idma64_hw_desc *hw;
+	size_t bytes = desc->length;
+	u64 llp = channel_readq(idma64c, LLP);
+	u32 ctlhi = channel_readl(idma64c, CTL_HI);
+	unsigned int i = 0;
+
+	do {
+		hw = &desc->hw[i];
+		if (hw->llp == llp)
+			break;
+		bytes -= hw->len;
+	} while (++i < desc->ndesc);
+
+	if (!i)
+		return bytes;
+
+	/* The current chunk is not fully transferred yet */
+	bytes += desc->hw[--i].len;
+
+	return bytes - IDMA64C_CTLH_BLOCK_TS(ctlhi);
+}
+
+static enum dma_status idma64_tx_status(struct dma_chan *chan,
+		dma_cookie_t cookie, struct dma_tx_state *state)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+	struct virt_dma_desc *vdesc;
+	enum dma_status status;
+	size_t bytes;
+	unsigned long flags;
+
+	status = dma_cookie_status(chan, cookie, state);
+	if (status == DMA_COMPLETE)
+		return status;
+
+	spin_lock_irqsave(&idma64c->vchan.lock, flags);
+	vdesc = vchan_find_desc(&idma64c->vchan, cookie);
+	if (idma64c->desc && cookie == idma64c->desc->vdesc.tx.cookie) {
+		bytes = idma64_active_desc_size(idma64c);
+		dma_set_residue(state, bytes);
+		status = idma64c->desc->status;
+	} else if (vdesc) {
+		bytes = to_idma64_desc(vdesc)->length;
+		dma_set_residue(state, bytes);
+	}
+	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
+
+	return status;
+}
+
+static void convert_burst(u32 *maxburst)
+{
+	if (*maxburst)
+		*maxburst = __fls(*maxburst);
+	else
+		*maxburst = 0;
+}
+
+static int idma64_slave_config(struct dma_chan *chan,
+		struct dma_slave_config *config)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+
+	memcpy(&idma64c->config, config, sizeof(idma64c->config));
+
+	convert_burst(&idma64c->config.src_maxburst);
+	convert_burst(&idma64c->config.dst_maxburst);
+
+	return 0;
+}
+
+static void idma64_chan_deactivate(struct idma64_chan *idma64c, bool drain)
+{
+	unsigned short count = 100;
+	u32 cfglo;
+
+	cfglo = channel_readl(idma64c, CFG_LO);
+	if (drain)
+		cfglo |= IDMA64C_CFGL_CH_DRAIN;
+	else
+		cfglo &= ~IDMA64C_CFGL_CH_DRAIN;
+
+	channel_writel(idma64c, CFG_LO, cfglo | IDMA64C_CFGL_CH_SUSP);
+	do {
+		udelay(1);
+		cfglo = channel_readl(idma64c, CFG_LO);
+	} while (!(cfglo & IDMA64C_CFGL_FIFO_EMPTY) && --count);
+}
+
+static void idma64_chan_activate(struct idma64_chan *idma64c)
+{
+	u32 cfglo;
+
+	cfglo = channel_readl(idma64c, CFG_LO);
+	channel_writel(idma64c, CFG_LO, cfglo & ~IDMA64C_CFGL_CH_SUSP);
+}
+
+static int idma64_pause(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&idma64c->vchan.lock, flags);
+	if (idma64c->desc && idma64c->desc->status == DMA_IN_PROGRESS) {
+		idma64_chan_deactivate(idma64c, false);
+		idma64c->desc->status = DMA_PAUSED;
+	}
+	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
+
+	return 0;
+}
+
+static int idma64_resume(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&idma64c->vchan.lock, flags);
+	if (idma64c->desc && idma64c->desc->status == DMA_PAUSED) {
+		idma64c->desc->status = DMA_IN_PROGRESS;
+		idma64_chan_activate(idma64c);
+	}
+	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
+
+	return 0;
+}
+
+static int idma64_terminate_all(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+	unsigned long flags;
+	LIST_HEAD(head);
+
+	spin_lock_irqsave(&idma64c->vchan.lock, flags);
+	idma64_chan_deactivate(idma64c, true);
+	idma64_stop_transfer(idma64c);
+	if (idma64c->desc) {
+		idma64_vdesc_free(&idma64c->desc->vdesc);
+		idma64c->desc = NULL;
+	}
+	vchan_get_all_descriptors(&idma64c->vchan, &head);
+	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
+
+	vchan_dma_desc_free_list(&idma64c->vchan, &head);
+	return 0;
+}
+
+static void idma64_synchronize(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+
+	vchan_synchronize(&idma64c->vchan);
+}
+
+static int idma64_alloc_chan_resources(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+
+	/* Create a pool of consistent memory blocks for hardware descriptors */
+	idma64c->pool = dma_pool_create(dev_name(chan2dev(chan)),
+					chan->device->dev,
+					sizeof(struct idma64_lli), 8, 0);
+	if (!idma64c->pool) {
+		dev_err(chan2dev(chan), "No memory for descriptors\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void idma64_free_chan_resources(struct dma_chan *chan)
+{
+	struct idma64_chan *idma64c = to_idma64_chan(chan);
+
+	vchan_free_chan_resources(to_virt_chan(chan));
+	dma_pool_destroy(idma64c->pool);
+	idma64c->pool = NULL;
+}
+
+/* ---------------------------------------------------------------------- */
+
+#define IDMA64_BUSWIDTHS				\
+	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
+
+static int idma64_probe(struct idma64_chip *chip)
+{
+	struct idma64 *idma64;
+	unsigned short nr_chan = IDMA64_NR_CHAN;
+	unsigned short i;
+	int ret;
+
+	idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL);
+	if (!idma64)
+		return -ENOMEM;
+
+	idma64->regs = chip->regs;
+	chip->idma64 = idma64;
+
+	idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan),
+				    GFP_KERNEL);
+	if (!idma64->chan)
+		return -ENOMEM;
+
+	idma64->all_chan_mask = (1 << nr_chan) - 1;
+
+	/* Turn off iDMA controller */
+	idma64_off(idma64);
+
+	ret = devm_request_irq(chip->dev, chip->irq, idma64_irq, IRQF_SHARED,
+			       dev_name(chip->dev), idma64);
+	if (ret)
+		return ret;
+
+	INIT_LIST_HEAD(&idma64->dma.channels);
+	for (i = 0; i < nr_chan; i++) {
+		struct idma64_chan *idma64c = &idma64->chan[i];
+
+		idma64c->vchan.desc_free = idma64_vdesc_free;
+		vchan_init(&idma64c->vchan, &idma64->dma);
+
+		idma64c->regs = idma64->regs + i * IDMA64_CH_LENGTH;
+		idma64c->mask = BIT(i);
+	}
+
+	dma_cap_set(DMA_SLAVE, idma64->dma.cap_mask);
+	dma_cap_set(DMA_PRIVATE, idma64->dma.cap_mask);
+
+	idma64->dma.device_alloc_chan_resources = idma64_alloc_chan_resources;
+	idma64->dma.device_free_chan_resources = idma64_free_chan_resources;
+
+	idma64->dma.device_prep_slave_sg = idma64_prep_slave_sg;
+
+	idma64->dma.device_issue_pending = idma64_issue_pending;
+	idma64->dma.device_tx_status = idma64_tx_status;
+
+	idma64->dma.device_config = idma64_slave_config;
+	idma64->dma.device_pause = idma64_pause;
+	idma64->dma.device_resume = idma64_resume;
+	idma64->dma.device_terminate_all = idma64_terminate_all;
+	idma64->dma.device_synchronize = idma64_synchronize;
+
+	idma64->dma.src_addr_widths = IDMA64_BUSWIDTHS;
+	idma64->dma.dst_addr_widths = IDMA64_BUSWIDTHS;
+	idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+	idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+	idma64->dma.dev = chip->sysdev;
+
+	dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
+
+	ret = dma_async_device_register(&idma64->dma);
+	if (ret)
+		return ret;
+
+	dev_info(chip->dev, "Found Intel integrated DMA 64-bit\n");
+	return 0;
+}
+
+static void idma64_remove(struct idma64_chip *chip)
+{
+	struct idma64 *idma64 = chip->idma64;
+	unsigned short i;
+
+	dma_async_device_unregister(&idma64->dma);
+
+	/*
+	 * Explicitly call devm_request_irq() to avoid the side effects with
+	 * the scheduled tasklets.
+	 */
+	devm_free_irq(chip->dev, chip->irq, idma64);
+
+	for (i = 0; i < idma64->dma.chancnt; i++) {
+		struct idma64_chan *idma64c = &idma64->chan[i];
+
+		tasklet_kill(&idma64c->vchan.task);
+	}
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int idma64_platform_probe(struct platform_device *pdev)
+{
+	struct idma64_chip *chip;
+	struct device *dev = &pdev->dev;
+	struct device *sysdev = dev->parent;
+	int ret;
+
+	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->irq = platform_get_irq(pdev, 0);
+	if (chip->irq < 0)
+		return chip->irq;
+
+	chip->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(chip->regs))
+		return PTR_ERR(chip->regs);
+
+	ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
+	if (ret)
+		return ret;
+
+	chip->dev = dev;
+	chip->sysdev = sysdev;
+
+	ret = idma64_probe(chip);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, chip);
+	return 0;
+}
+
+static void idma64_platform_remove(struct platform_device *pdev)
+{
+	struct idma64_chip *chip = platform_get_drvdata(pdev);
+
+	idma64_remove(chip);
+}
+
+static int __maybe_unused idma64_pm_suspend(struct device *dev)
+{
+	struct idma64_chip *chip = dev_get_drvdata(dev);
+
+	idma64_off(chip->idma64);
+	return 0;
+}
+
+static int __maybe_unused idma64_pm_resume(struct device *dev)
+{
+	struct idma64_chip *chip = dev_get_drvdata(dev);
+
+	idma64_on(chip->idma64);
+	return 0;
+}
+
+static const struct dev_pm_ops idma64_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
+};
+
+static struct platform_driver idma64_platform_driver = {
+	.probe		= idma64_platform_probe,
+	.remove		= idma64_platform_remove,
+	.driver = {
+		.name	= LPSS_IDMA64_DRIVER_NAME,
+		.pm	= &idma64_dev_pm_ops,
+	},
+};
+
+module_platform_driver(idma64_platform_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("iDMA64 core driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_ALIAS("platform:" LPSS_IDMA64_DRIVER_NAME);