Merge branch 'acpi-pm'

* acpi-pm:
  ACPI / bus: Move duplicate code to a separate new function
  mfd: Add support for Intel Sunrisepoint LPSS devices
  dmaengine: add a driver for Intel integrated DMA 64-bit
  mfd: make mfd_remove_devices() iterate in reverse order
  driver core: implement device_for_each_child_reverse()
  klist: implement klist_prev()
  Driver core: wakeup the parent device before trying probe
  ACPI / PM: Attach ACPI power domain only once
  PM / QoS: Make it possible to expose device latency tolerance to userspace
  ACPI / PM: Update the copyright notice and description of power.c

25 files changed, 1981 insertions, 24 deletions

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 54a2e66ce236..46506e7687cd 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -482,6 +482,43 @@ static void acpi_device_remove_notify_handler(struct acpi_device *device)
                              Device Matching
    -------------------------------------------------------------------------- */
 
+static struct acpi_device *acpi_primary_dev_companion(struct acpi_device *adev,
+						      const struct device *dev)
+{
+	struct mutex *physical_node_lock = &adev->physical_node_lock;
+
+	mutex_lock(physical_node_lock);
+	if (list_empty(&adev->physical_node_list)) {
+		adev = NULL;
+	} else {
+		const struct acpi_device_physical_node *node;
+
+		node = list_first_entry(&adev->physical_node_list,
+					struct acpi_device_physical_node, node);
+		if (node->dev != dev)
+			adev = NULL;
+	}
+	mutex_unlock(physical_node_lock);
+	return adev;
+}
+
+/**
+ * acpi_device_is_first_physical_node - Is given dev first physical node
+ * @adev: ACPI companion device
+ * @dev: Physical device to check
+ *
+ * Function checks if given @dev is the first physical devices attached to
+ * the ACPI companion device. This distinction is needed in some cases
+ * where the same companion device is shared between many physical devices.
+ *
+ * Note that the caller have to provide valid @adev pointer.
+ */
+bool acpi_device_is_first_physical_node(struct acpi_device *adev,
+					const struct device *dev)
+{
+	return !!acpi_primary_dev_companion(adev, dev);
+}
+
 /*
  * acpi_companion_match() - Can we match via ACPI companion device
  * @dev: Device in question
@@ -506,7 +543,6 @@ static void acpi_device_remove_notify_handler(struct acpi_device *device)
 struct acpi_device *acpi_companion_match(const struct device *dev)
 {
 	struct acpi_device *adev;
-	struct mutex *physical_node_lock;
 
 	adev = ACPI_COMPANION(dev);
 	if (!adev)
@@ -515,21 +551,7 @@ struct acpi_device *acpi_companion_match(const struct device *dev)
 	if (list_empty(&adev->pnp.ids))
 		return NULL;
 
-	physical_node_lock = &adev->physical_node_lock;
-	mutex_lock(physical_node_lock);
-	if (list_empty(&adev->physical_node_list)) {
-		adev = NULL;
-	} else {
-		const struct acpi_device_physical_node *node;
-
-		node = list_first_entry(&adev->physical_node_list,
-					struct acpi_device_physical_node, node);
-		if (node->dev != dev)
-			adev = NULL;
-	}
-	mutex_unlock(physical_node_lock);
-
-	return adev;
+	return acpi_primary_dev_companion(adev, dev);
 }
 
 /**
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index da0867899d10..4806b7f856c4 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -1119,6 +1119,14 @@ int acpi_dev_pm_attach(struct device *dev, bool power_on)
 	if (dev->pm_domain)
 		return -EEXIST;
 
+	/*
+	 * Only attach the power domain to the first device if the
+	 * companion is shared by multiple. This is to prevent doing power
+	 * management twice.
+	 */
+	if (!acpi_device_is_first_physical_node(adev, dev))
+		return -EBUSY;
+
 	acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
 	dev->pm_domain = &acpi_general_pm_domain;
 	if (power_on) {
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 2c195cd5ab1b..9e426210c2a8 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -96,6 +96,8 @@ void acpi_device_add_finalize(struct acpi_device *device);
 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp);
 bool acpi_device_is_present(struct acpi_device *adev);
 bool acpi_device_is_battery(struct acpi_device *adev);
+bool acpi_device_is_first_physical_node(struct acpi_device *adev,
+					const struct device *dev);
 
 /* --------------------------------------------------------------------------
                      Device Matching and Notification
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 45b47f2c9f03..fcd4ce6f78d5 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -1,8 +1,10 @@
 /*
- *  acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
+ * drivers/acpi/power.c - ACPI Power Resources management.
  *
- *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
- *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2001 - 2015 Intel Corp.
+ * Author: Andy Grover <andrew.grover@intel.com>
+ * Author: Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  *
@@ -23,10 +25,11 @@
  * ACPI power-managed devices may be controlled in two ways:
  * 1. via "Device Specific (D-State) Control"
  * 2. via "Power Resource Control".
- * This module is used to manage devices relying on Power Resource Control.
+ * The code below deals with ACPI Power Resources control.
  * 
- * An ACPI "power resource object" describes a software controllable power
- * plane, clock plane, or other resource used by a power managed device.
+ * An ACPI "power resource object" represents a software controllable power
+ * plane, clock plane, or other resource depended on by a device.
+ *
  * A device may rely on multiple power resources, and a power resource
  * may be shared by multiple devices.
  */
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 2fe5a37c385c..01136b879038 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -115,7 +115,6 @@ int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
 	return 0;
 }
 
-
 bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
 {
 	struct acpi_device_physical_node *pn;
diff --git a/drivers/base/core.c b/drivers/base/core.c
index dafae6d2f7ac..7d6279554afc 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1252,6 +1252,19 @@ void device_unregister(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(device_unregister);
 
+static struct device *prev_device(struct klist_iter *i)
+{
+	struct klist_node *n = klist_prev(i);
+	struct device *dev = NULL;
+	struct device_private *p;
+
+	if (n) {
+		p = to_device_private_parent(n);
+		dev = p->device;
+	}
+	return dev;
+}
+
 static struct device *next_device(struct klist_iter *i)
 {
 	struct klist_node *n = klist_next(i);
@@ -1341,6 +1354,36 @@ int device_for_each_child(struct device *parent, void *data,
 EXPORT_SYMBOL_GPL(device_for_each_child);
 
 /**
+ * device_for_each_child_reverse - device child iterator in reversed order.
+ * @parent: parent struct device.
+ * @fn: function to be called for each device.
+ * @data: data for the callback.
+ *
+ * Iterate over @parent's child devices, and call @fn for each,
+ * passing it @data.
+ *
+ * We check the return of @fn each time. If it returns anything
+ * other than 0, we break out and return that value.
+ */
+int device_for_each_child_reverse(struct device *parent, void *data,
+				  int (*fn)(struct device *dev, void *data))
+{
+	struct klist_iter i;
+	struct device *child;
+	int error = 0;
+
+	if (!parent->p)
+		return 0;
+
+	klist_iter_init(&parent->p->klist_children, &i);
+	while ((child = prev_device(&i)) && !error)
+		error = fn(child, data);
+	klist_iter_exit(&i);
+	return error;
+}
+EXPORT_SYMBOL_GPL(device_for_each_child_reverse);
+
+/**
  * device_find_child - device iterator for locating a particular device.
  * @parent: parent struct device
  * @match: Callback function to check device
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index a638bbb1a27a..2d6df1dd3852 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -399,6 +399,8 @@ EXPORT_SYMBOL_GPL(wait_for_device_probe);
  *
  * This function must be called with @dev lock held.  When called for a
  * USB interface, @dev->parent lock must be held as well.
+ *
+ * If the device has a parent, runtime-resume the parent before driver probing.
  */
 int driver_probe_device(struct device_driver *drv, struct device *dev)
 {
@@ -410,10 +412,16 @@ int driver_probe_device(struct device_driver *drv, struct device *dev)
 	pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
 		 drv->bus->name, __func__, dev_name(dev), drv->name);
 
+	if (dev->parent)
+		pm_runtime_get_sync(dev->parent);
+
 	pm_runtime_barrier(dev);
 	ret = really_probe(dev, drv);
 	pm_request_idle(dev);
 
+	if (dev->parent)
+		pm_runtime_put(dev->parent);
+
 	return ret;
 }
 
@@ -507,11 +515,17 @@ static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
 
 	device_lock(dev);
 
+	if (dev->parent)
+		pm_runtime_get_sync(dev->parent);
+
 	bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver);
 	dev_dbg(dev, "async probe completed\n");
 
 	pm_request_idle(dev);
 
+	if (dev->parent)
+		pm_runtime_put(dev->parent);
+
 	device_unlock(dev);
 
 	put_device(dev);
@@ -541,6 +555,9 @@ static int __device_attach(struct device *dev, bool allow_async)
 			.want_async = false,
 		};
 
+		if (dev->parent)
+			pm_runtime_get_sync(dev->parent);
+
 		ret = bus_for_each_drv(dev->bus, NULL, &data,
 					__device_attach_driver);
 		if (!ret && allow_async && data.have_async) {
@@ -557,6 +574,9 @@ static int __device_attach(struct device *dev, bool allow_async)
 		} else {
 			pm_request_idle(dev);
 		}
+
+		if (dev->parent)
+			pm_runtime_put(dev->parent);
 	}
 out_unlock:
 	device_unlock(dev);
diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index f1a5d95e7b20..998fa6b23084 100644
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -73,6 +73,8 @@ extern int pm_qos_sysfs_add_resume_latency(struct device *dev);
 extern void pm_qos_sysfs_remove_resume_latency(struct device *dev);
 extern int pm_qos_sysfs_add_flags(struct device *dev);
 extern void pm_qos_sysfs_remove_flags(struct device *dev);
+extern int pm_qos_sysfs_add_latency_tolerance(struct device *dev);
+extern void pm_qos_sysfs_remove_latency_tolerance(struct device *dev);
 
 #else /* CONFIG_PM */
 
diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
index e56d538d039e..7f3646e459cb 100644
--- a/drivers/base/power/qos.c
+++ b/drivers/base/power/qos.c
@@ -883,3 +883,40 @@ int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val)
 	mutex_unlock(&dev_pm_qos_mtx);
 	return ret;
 }
+
+/**
+ * dev_pm_qos_expose_latency_tolerance - Expose latency tolerance to userspace
+ * @dev: Device whose latency tolerance to expose
+ */
+int dev_pm_qos_expose_latency_tolerance(struct device *dev)
+{
+	int ret;
+
+	if (!dev->power.set_latency_tolerance)
+		return -EINVAL;
+
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
+	ret = pm_qos_sysfs_add_latency_tolerance(dev);
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_tolerance);
+
+/**
+ * dev_pm_qos_hide_latency_tolerance - Hide latency tolerance from userspace
+ * @dev: Device whose latency tolerance to hide
+ */
+void dev_pm_qos_hide_latency_tolerance(struct device *dev)
+{
+	mutex_lock(&dev_pm_qos_sysfs_mtx);
+	pm_qos_sysfs_remove_latency_tolerance(dev);
+	mutex_unlock(&dev_pm_qos_sysfs_mtx);
+
+	/* Remove the request from user space now */
+	pm_runtime_get_sync(dev);
+	dev_pm_qos_update_user_latency_tolerance(dev,
+		PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT);
+	pm_runtime_put(dev);
+}
+EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_tolerance);
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index d2be3f9c211c..a7b46798c81d 100644
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -738,6 +738,17 @@ void pm_qos_sysfs_remove_flags(struct device *dev)
 	sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
 }
 
+int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
+{
+	return sysfs_merge_group(&dev->kobj,
+				 &pm_qos_latency_tolerance_attr_group);
+}
+
+void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
+{
+	sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
+}
+
 void rpm_sysfs_remove(struct device *dev)
 {
 	sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 88d474b78076..bdbbe5bcfb83 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -85,6 +85,14 @@ config INTEL_IOP_ADMA
 	help
 	  Enable support for the Intel(R) IOP Series RAID engines.
 
+config IDMA64
+	tristate "Intel integrated DMA 64-bit support"
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  Enable DMA support for Intel Low Power Subsystem such as found on
+	  Intel Skylake PCH.
+
 source "drivers/dma/dw/Kconfig"
 
 config AT_HDMAC
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 6a4d6f2827da..56ff8c705c00 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_HSU_DMA) += hsu/
 obj-$(CONFIG_MPC512X_DMA) += mpc512x_dma.o
 obj-$(CONFIG_PPC_BESTCOMM) += bestcomm/
 obj-$(CONFIG_MV_XOR) += mv_xor.o
+obj-$(CONFIG_IDMA64) += idma64.o
 obj-$(CONFIG_DW_DMAC_CORE) += dw/
 obj-$(CONFIG_AT_HDMAC) += at_hdmac.o
 obj-$(CONFIG_AT_XDMAC) += at_xdmac.o
diff --git a/drivers/dma/idma64.c b/drivers/dma/idma64.c
new file mode 100644
index 000000000000..18c14e1f1414
--- /dev/null
+++ b/drivers/dma/idma64.c
@@ -0,0 +1,710 @@
+/*
+ * Core driver for the Intel integrated DMA 64-bit
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#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 "idma64.h"
+
+/* Platform driver name */
+#define DRV_NAME		"idma64"
+
+/* 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;
+
+	/* Enforce FIFO drain when channel is suspended */
+	cfglo |= IDMA64C_CFGL_CH_DRAIN;
+
+	/* 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 idma64_desc *desc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&idma64c->vchan.lock, flags);
+	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);
+			idma64_start_transfer(idma64c);
+		}
+
+		/* idma64_start_transfer() updates idma64c->desc */
+		if (idma64c->desc == NULL || desc->status == DMA_ERROR)
+			idma64_stop_transfer(idma64c);
+	}
+	spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
+}
+
+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;
+
+	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;
+
+	/* Disable interrupts */
+	channel_clear_bit(idma64, MASK(XFER), idma64->all_chan_mask);
+	channel_clear_bit(idma64, MASK(ERROR), idma64->all_chan_mask);
+
+	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);
+
+	/* Re-enable interrupts */
+	channel_set_bit(idma64, MASK(XFER), idma64->all_chan_mask);
+	channel_set_bit(idma64, MASK(ERROR), idma64->all_chan_mask);
+
+	return IRQ_HANDLED;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
+{
+	struct idma64_desc *desc;
+
+	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
+	if (!desc)
+		return NULL;
+
+	desc->hw = kcalloc(ndesc, sizeof(*desc->hw), 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 u64 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 = min_t(u32, 2, __fls(sar | hw->len));
+		dst_width = __fls(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 = __fls(config->src_addr_width);
+		dst_width = min_t(u32, 2, __fls(dar | hw->len));
+	}
+
+	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;
+	return hw->llp;
+}
+
+static void idma64_desc_fill(struct idma64_chan *idma64c,
+		struct idma64_desc *desc)
+{
+	struct dma_slave_config *config = &idma64c->config;
+	struct idma64_hw_desc *hw = &desc->hw[desc->ndesc - 1];
+	struct idma64_lli *lli = hw->lli;
+	u64 llp = 0;
+	unsigned int i = desc->ndesc;
+
+	/* Fill the hardware descriptors and link them to a list */
+	do {
+		hw = &desc->hw[--i];
+		llp = idma64_hw_desc_fill(hw, config, desc->direction, llp);
+		desc->length += hw->len;
+	} while (i);
+
+	/* Trigger interrupt after last block */
+	lli->ctllo |= IDMA64C_CTLL_INT_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;
+	u32 ctlhi;
+	unsigned int i = 0;
+
+	llp = channel_readq(idma64c, LLP);
+	do {
+		hw = &desc->hw[i];
+	} while ((hw->llp != llp) && (++i < desc->ndesc));
+
+	if (!i)
+		return bytes;
+
+	do {
+		bytes -= desc->hw[--i].len;
+	} while (i);
+
+	ctlhi = channel_readl(idma64c, CTL_HI);
+	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);
+
+	/* Check if chan will be configured for slave transfers */
+	if (!is_slave_direction(config->direction))
+		return -EINVAL;
+
+	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)
+{
+	unsigned short count = 100;
+	u32 cfglo;
+
+	cfglo = channel_readl(idma64c, CFG_LO);
+	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);
+		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);
+	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 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.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->dev;
+
+	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 int 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);
+	}
+
+	return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+
+static int idma64_platform_probe(struct platform_device *pdev)
+{
+	struct idma64_chip *chip;
+	struct device *dev = &pdev->dev;
+	struct resource *mem;
+	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;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	chip->regs = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(chip->regs))
+		return PTR_ERR(chip->regs);
+
+	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (ret)
+		return ret;
+
+	chip->dev = dev;
+
+	ret = idma64_probe(chip);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, chip);
+	return 0;
+}
+
+static int idma64_platform_remove(struct platform_device *pdev)
+{
+	struct idma64_chip *chip = platform_get_drvdata(pdev);
+
+	return idma64_remove(chip);
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int idma64_pm_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct idma64_chip *chip = platform_get_drvdata(pdev);
+
+	idma64_off(chip->idma64);
+	return 0;
+}
+
+static int idma64_pm_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct idma64_chip *chip = platform_get_drvdata(pdev);
+
+	idma64_on(chip->idma64);
+	return 0;
+}
+
+#endif /* CONFIG_PM_SLEEP */
+
+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	= DRV_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:" DRV_NAME);
diff --git a/drivers/dma/idma64.h b/drivers/dma/idma64.h
new file mode 100644
index 000000000000..a4d99685a7c4
--- /dev/null
+++ b/drivers/dma/idma64.h
@@ -0,0 +1,233 @@
+/*
+ * Driver for the Intel integrated DMA 64-bit
+ *
+ * Copyright (C) 2015 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __DMA_IDMA64_H__
+#define __DMA_IDMA64_H__
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include "virt-dma.h"
+
+/* Channel registers */
+
+#define IDMA64_CH_SAR		0x00	/* Source Address Register */
+#define IDMA64_CH_DAR		0x08	/* Destination Address Register */
+#define IDMA64_CH_LLP		0x10	/* Linked List Pointer */
+#define IDMA64_CH_CTL_LO	0x18	/* Control Register Low */
+#define IDMA64_CH_CTL_HI	0x1c	/* Control Register High */
+#define IDMA64_CH_SSTAT		0x20
+#define IDMA64_CH_DSTAT		0x28
+#define IDMA64_CH_SSTATAR	0x30
+#define IDMA64_CH_DSTATAR	0x38
+#define IDMA64_CH_CFG_LO	0x40	/* Configuration Register Low */
+#define IDMA64_CH_CFG_HI	0x44	/* Configuration Register High */
+#define IDMA64_CH_SGR		0x48
+#define IDMA64_CH_DSR		0x50
+
+#define IDMA64_CH_LENGTH	0x58
+
+/* Bitfields in CTL_LO */
+#define IDMA64C_CTLL_INT_EN		(1 << 0)	/* irqs enabled? */
+#define IDMA64C_CTLL_DST_WIDTH(x)	((x) << 1)	/* bytes per element */
+#define IDMA64C_CTLL_SRC_WIDTH(x)	((x) << 4)
+#define IDMA64C_CTLL_DST_INC		(0 << 8)	/* DAR update/not */
+#define IDMA64C_CTLL_DST_FIX		(1 << 8)
+#define IDMA64C_CTLL_SRC_INC		(0 << 10)	/* SAR update/not */
+#define IDMA64C_CTLL_SRC_FIX		(1 << 10)
+#define IDMA64C_CTLL_DST_MSIZE(x)	((x) << 11)	/* burst, #elements */
+#define IDMA64C_CTLL_SRC_MSIZE(x)	((x) << 14)
+#define IDMA64C_CTLL_FC_M2P		(1 << 20)	/* mem-to-periph */
+#define IDMA64C_CTLL_FC_P2M		(2 << 20)	/* periph-to-mem */
+#define IDMA64C_CTLL_LLP_D_EN		(1 << 27)	/* dest block chain */
+#define IDMA64C_CTLL_LLP_S_EN		(1 << 28)	/* src block chain */
+
+/* Bitfields in CTL_HI */
+#define IDMA64C_CTLH_BLOCK_TS(x)	((x) & ((1 << 17) - 1))
+#define IDMA64C_CTLH_DONE		(1 << 17)
+
+/* Bitfields in CFG_LO */
+#define IDMA64C_CFGL_DST_BURST_ALIGN	(1 << 0)	/* dst burst align */
+#define IDMA64C_CFGL_SRC_BURST_ALIGN	(1 << 1)	/* src burst align */
+#define IDMA64C_CFGL_CH_SUSP		(1 << 8)
+#define IDMA64C_CFGL_FIFO_EMPTY		(1 << 9)
+#define IDMA64C_CFGL_CH_DRAIN		(1 << 10)	/* drain FIFO */
+#define IDMA64C_CFGL_DST_OPT_BL		(1 << 20)	/* optimize dst burst length */
+#define IDMA64C_CFGL_SRC_OPT_BL		(1 << 21)	/* optimize src burst length */
+
+/* Bitfields in CFG_HI */
+#define IDMA64C_CFGH_SRC_PER(x)		((x) << 0)	/* src peripheral */
+#define IDMA64C_CFGH_DST_PER(x)		((x) << 4)	/* dst peripheral */
+#define IDMA64C_CFGH_RD_ISSUE_THD(x)	((x) << 8)
+#define IDMA64C_CFGH_RW_ISSUE_THD(x)	((x) << 18)
+
+/* Interrupt registers */
+
+#define IDMA64_INT_XFER		0x00
+#define IDMA64_INT_BLOCK	0x08
+#define IDMA64_INT_SRC_TRAN	0x10
+#define IDMA64_INT_DST_TRAN	0x18
+#define IDMA64_INT_ERROR	0x20
+
+#define IDMA64_RAW(x)		(0x2c0 + IDMA64_INT_##x)	/* r */
+#define IDMA64_STATUS(x)	(0x2e8 + IDMA64_INT_##x)	/* r (raw & mask) */
+#define IDMA64_MASK(x)		(0x310 + IDMA64_INT_##x)	/* rw (set = irq enabled) */
+#define IDMA64_CLEAR(x)		(0x338 + IDMA64_INT_##x)	/* w (ack, affects "raw") */
+
+/* Common registers */
+
+#define IDMA64_STATUS_INT	0x360	/* r */
+#define IDMA64_CFG		0x398
+#define IDMA64_CH_EN		0x3a0
+
+/* Bitfields in CFG */
+#define IDMA64_CFG_DMA_EN		(1 << 0)
+
+/* Hardware descriptor for Linked LIst transfers */
+struct idma64_lli {
+	u64		sar;
+	u64		dar;
+	u64		llp;
+	u32		ctllo;
+	u32		ctlhi;
+	u32		sstat;
+	u32		dstat;
+};
+
+struct idma64_hw_desc {
+	struct idma64_lli *lli;
+	dma_addr_t llp;
+	dma_addr_t phys;
+	unsigned int len;
+};
+
+struct idma64_desc {
+	struct virt_dma_desc vdesc;
+	enum dma_transfer_direction direction;
+	struct idma64_hw_desc *hw;
+	unsigned int ndesc;
+	size_t length;
+	enum dma_status status;
+};
+
+static inline struct idma64_desc *to_idma64_desc(struct virt_dma_desc *vdesc)
+{
+	return container_of(vdesc, struct idma64_desc, vdesc);
+}
+
+struct idma64_chan {
+	struct virt_dma_chan vchan;
+
+	void __iomem *regs;
+
+	/* hardware configuration */
+	enum dma_transfer_direction direction;
+	unsigned int mask;
+	struct dma_slave_config config;
+
+	void *pool;
+	struct idma64_desc *desc;
+};
+
+static inline struct idma64_chan *to_idma64_chan(struct dma_chan *chan)
+{
+	return container_of(chan, struct idma64_chan, vchan.chan);
+}
+
+#define channel_set_bit(idma64, reg, mask)	\
+	dma_writel(idma64, reg, ((mask) << 8) | (mask))
+#define channel_clear_bit(idma64, reg, mask)	\
+	dma_writel(idma64, reg, ((mask) << 8) | 0)
+
+static inline u32 idma64c_readl(struct idma64_chan *idma64c, int offset)
+{
+	return readl(idma64c->regs + offset);
+}
+
+static inline void idma64c_writel(struct idma64_chan *idma64c, int offset,
+				  u32 value)
+{
+	writel(value, idma64c->regs + offset);
+}
+
+#define channel_readl(idma64c, reg)		\
+	idma64c_readl(idma64c, IDMA64_CH_##reg)
+#define channel_writel(idma64c, reg, value)	\
+	idma64c_writel(idma64c, IDMA64_CH_##reg, (value))
+
+static inline u64 idma64c_readq(struct idma64_chan *idma64c, int offset)
+{
+	u64 l, h;
+
+	l = idma64c_readl(idma64c, offset);
+	h = idma64c_readl(idma64c, offset + 4);
+
+	return l | (h << 32);
+}
+
+static inline void idma64c_writeq(struct idma64_chan *idma64c, int offset,
+				  u64 value)
+{
+	idma64c_writel(idma64c, offset, value);
+	idma64c_writel(idma64c, offset + 4, value >> 32);
+}
+
+#define channel_readq(idma64c, reg)		\
+	idma64c_readq(idma64c, IDMA64_CH_##reg)
+#define channel_writeq(idma64c, reg, value)	\
+	idma64c_writeq(idma64c, IDMA64_CH_##reg, (value))
+
+struct idma64 {
+	struct dma_device dma;
+
+	void __iomem *regs;
+
+	/* channels */
+	unsigned short all_chan_mask;
+	struct idma64_chan *chan;
+};
+
+static inline struct idma64 *to_idma64(struct dma_device *ddev)
+{
+	return container_of(ddev, struct idma64, dma);
+}
+
+static inline u32 idma64_readl(struct idma64 *idma64, int offset)
+{
+	return readl(idma64->regs + offset);
+}
+
+static inline void idma64_writel(struct idma64 *idma64, int offset, u32 value)
+{
+	writel(value, idma64->regs + offset);
+}
+
+#define dma_readl(idma64, reg)			\
+	idma64_readl(idma64, IDMA64_##reg)
+#define dma_writel(idma64, reg, value)		\
+	idma64_writel(idma64, IDMA64_##reg, (value))
+
+/**
+ * struct idma64_chip - representation of DesignWare DMA controller hardware
+ * @dev:		struct device of the DMA controller
+ * @irq:		irq line
+ * @regs:		memory mapped I/O space
+ * @idma64:		struct idma64 that is filed by idma64_probe()
+ */
+struct idma64_chip {
+	struct device	*dev;
+	int		irq;
+	void __iomem	*regs;
+	struct idma64	*idma64;
+};
+
+#endif /* __DMA_IDMA64_H__ */
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 3f68dd251ce8..076f593f90d3 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -328,6 +328,29 @@ config INTEL_SOC_PMIC
 	  thermal, charger and related power management functions
 	  on these systems.
 
+config MFD_INTEL_LPSS
+	tristate
+	select COMMON_CLK
+	select MFD_CORE
+
+config MFD_INTEL_LPSS_ACPI
+	tristate "Intel Low Power Subsystem support in ACPI mode"
+	select MFD_INTEL_LPSS
+	depends on X86 && ACPI
+	help
+	  This driver supports Intel Low Power Subsystem (LPSS) devices such as
+	  I2C, SPI and HS-UART starting from Intel Sunrisepoint (Intel Skylake
+	  PCH) in ACPI mode.
+
+config MFD_INTEL_LPSS_PCI
+	tristate "Intel Low Power Subsystem support in PCI mode"
+	select MFD_INTEL_LPSS
+	depends on X86 && PCI
+	help
+	  This driver supports Intel Low Power Subsystem (LPSS) devices such as
+	  I2C, SPI and HS-UART starting from Intel Sunrisepoint (Intel Skylake
+	  PCH) in PCI mode.
+
 config MFD_INTEL_MSIC
 	bool "Intel MSIC"
 	depends on INTEL_SCU_IPC
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index ea40e076cb61..9d730a2d1878 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -161,6 +161,9 @@ obj-$(CONFIG_TPS65911_COMPARATOR)	+= tps65911-comparator.o
 obj-$(CONFIG_MFD_TPS65090)	+= tps65090.o
 obj-$(CONFIG_MFD_AAT2870_CORE)	+= aat2870-core.o
 obj-$(CONFIG_MFD_ATMEL_HLCDC)	+= atmel-hlcdc.o
+obj-$(CONFIG_MFD_INTEL_LPSS)	+= intel-lpss.o
+obj-$(CONFIG_MFD_INTEL_LPSS_PCI)	+= intel-lpss-pci.o
+obj-$(CONFIG_MFD_INTEL_LPSS_ACPI)	+= intel-lpss-acpi.o
 obj-$(CONFIG_MFD_INTEL_MSIC)	+= intel_msic.o
 obj-$(CONFIG_MFD_PALMAS)	+= palmas.o
 obj-$(CONFIG_MFD_VIPERBOARD)    += viperboard.o
diff --git a/drivers/mfd/intel-lpss-acpi.c b/drivers/mfd/intel-lpss-acpi.c
new file mode 100644
index 000000000000..0d92d73bfa0e
--- /dev/null
+++ b/drivers/mfd/intel-lpss-acpi.c
@@ -0,0 +1,84 @@
+/*
+ * Intel LPSS ACPI support.
+ *
+ * Copyright (C) 2015, Intel Corporation
+ *
+ * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+#include <linux/platform_device.h>
+
+#include "intel-lpss.h"
+
+static const struct intel_lpss_platform_info spt_info = {
+	.clk_rate = 120000000,
+};
+
+static const struct acpi_device_id intel_lpss_acpi_ids[] = {
+	/* SPT */
+	{ "INT3446", (kernel_ulong_t)&spt_info },
+	{ "INT3447", (kernel_ulong_t)&spt_info },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, intel_lpss_acpi_ids);
+
+static int intel_lpss_acpi_probe(struct platform_device *pdev)
+{
+	struct intel_lpss_platform_info *info;
+	const struct acpi_device_id *id;
+
+	id = acpi_match_device(intel_lpss_acpi_ids, &pdev->dev);
+	if (!id)
+		return -ENODEV;
+
+	info = devm_kmemdup(&pdev->dev, (void *)id->driver_data, sizeof(*info),
+			    GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	info->irq = platform_get_irq(pdev, 0);
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	return intel_lpss_probe(&pdev->dev, info);
+}
+
+static int intel_lpss_acpi_remove(struct platform_device *pdev)
+{
+	intel_lpss_remove(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static INTEL_LPSS_PM_OPS(intel_lpss_acpi_pm_ops);
+
+static struct platform_driver intel_lpss_acpi_driver = {
+	.probe = intel_lpss_acpi_probe,
+	.remove = intel_lpss_acpi_remove,
+	.driver = {
+		.name = "intel-lpss",
+		.acpi_match_table = intel_lpss_acpi_ids,
+		.pm = &intel_lpss_acpi_pm_ops,
+	},
+};
+
+module_platform_driver(intel_lpss_acpi_driver);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_DESCRIPTION("Intel LPSS ACPI driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
new file mode 100644
index 000000000000..9236dffeb4d6
--- /dev/null
+++ b/drivers/mfd/intel-lpss-pci.c
@@ -0,0 +1,113 @@
+/*
+ * Intel LPSS PCI support.
+ *
+ * Copyright (C) 2015, Intel Corporation
+ *
+ * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+
+#include "intel-lpss.h"
+
+static int intel_lpss_pci_probe(struct pci_dev *pdev,
+				const struct pci_device_id *id)
+{
+	struct intel_lpss_platform_info *info;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return ret;
+
+	info = devm_kmemdup(&pdev->dev, (void *)id->driver_data, sizeof(*info),
+			    GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->mem = &pdev->resource[0];
+	info->irq = pdev->irq;
+
+	/* Probably it is enough to set this for iDMA capable devices only */
+	pci_set_master(pdev);
+
+	ret = intel_lpss_probe(&pdev->dev, info);
+	if (ret)
+		return ret;
+
+	pm_runtime_put(&pdev->dev);
+	pm_runtime_allow(&pdev->dev);
+
+	return 0;
+}
+
+static void intel_lpss_pci_remove(struct pci_dev *pdev)
+{
+	pm_runtime_forbid(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	intel_lpss_remove(&pdev->dev);
+}
+
+static INTEL_LPSS_PM_OPS(intel_lpss_pci_pm_ops);
+
+static const struct intel_lpss_platform_info spt_info = {
+	.clk_rate = 120000000,
+};
+
+static const struct intel_lpss_platform_info spt_uart_info = {
+	.clk_rate = 120000000,
+	.clk_con_id = "baudclk",
+};
+
+static const struct pci_device_id intel_lpss_pci_ids[] = {
+	/* SPT-LP */
+	{ PCI_VDEVICE(INTEL, 0x9d27), (kernel_ulong_t)&spt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0x9d28), (kernel_ulong_t)&spt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0x9d29), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d2a), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d60), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d61), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d62), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d63), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d64), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d65), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0x9d66), (kernel_ulong_t)&spt_uart_info },
+	/* SPT-H */
+	{ PCI_VDEVICE(INTEL, 0xa127), (kernel_ulong_t)&spt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0xa128), (kernel_ulong_t)&spt_uart_info },
+	{ PCI_VDEVICE(INTEL, 0xa129), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0xa12a), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0xa160), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0xa161), (kernel_ulong_t)&spt_info },
+	{ PCI_VDEVICE(INTEL, 0xa166), (kernel_ulong_t)&spt_uart_info },
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, intel_lpss_pci_ids);
+
+static struct pci_driver intel_lpss_pci_driver = {
+	.name = "intel-lpss",
+	.id_table = intel_lpss_pci_ids,
+	.probe = intel_lpss_pci_probe,
+	.remove = intel_lpss_pci_remove,
+	.driver = {
+		.pm = &intel_lpss_pci_pm_ops,
+	},
+};
+
+module_pci_driver(intel_lpss_pci_driver);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_DESCRIPTION("Intel LPSS PCI driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c
new file mode 100644
index 000000000000..fdf4d5c1add2
--- /dev/null
+++ b/drivers/mfd/intel-lpss.c
@@ -0,0 +1,524 @@
+/*
+ * Intel Sunrisepoint LPSS core support.
+ *
+ * Copyright (C) 2015, Intel Corporation
+ *
+ * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *          Heikki Krogerus <heikki.krogerus@linux.intel.com>
+ *          Jarkko Nikula <jarkko.nikula@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/debugfs.h>
+#include <linux/idr.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mfd/core.h>
+#include <linux/pm_qos.h>
+#include <linux/pm_runtime.h>
+#include <linux/seq_file.h>
+
+#include "intel-lpss.h"
+
+#define LPSS_DEV_OFFSET		0x000
+#define LPSS_DEV_SIZE		0x200
+#define LPSS_PRIV_OFFSET	0x200
+#define LPSS_PRIV_SIZE		0x100
+#define LPSS_IDMA64_OFFSET	0x800
+#define LPSS_IDMA64_SIZE	0x800
+
+/* Offsets from lpss->priv */
+#define LPSS_PRIV_RESETS		0x04
+#define LPSS_PRIV_RESETS_FUNC		BIT(2)
+#define LPSS_PRIV_RESETS_IDMA		0x3
+
+#define LPSS_PRIV_ACTIVELTR		0x10
+#define LPSS_PRIV_IDLELTR		0x14
+
+#define LPSS_PRIV_LTR_REQ		BIT(15)
+#define LPSS_PRIV_LTR_SCALE_MASK	0xc00
+#define LPSS_PRIV_LTR_SCALE_1US		0x800
+#define LPSS_PRIV_LTR_SCALE_32US	0xc00
+#define LPSS_PRIV_LTR_VALUE_MASK	0x3ff
+
+#define LPSS_PRIV_SSP_REG		0x20
+#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN	BIT(0)
+
+#define LPSS_PRIV_REMAP_ADDR_LO		0x40
+#define LPSS_PRIV_REMAP_ADDR_HI		0x44
+
+#define LPSS_PRIV_CAPS			0xfc
+#define LPSS_PRIV_CAPS_NO_IDMA		BIT(8)
+#define LPSS_PRIV_CAPS_TYPE_SHIFT	4
+#define LPSS_PRIV_CAPS_TYPE_MASK	(0xf << LPSS_PRIV_CAPS_TYPE_SHIFT)
+
+/* This matches the type field in CAPS register */
+enum intel_lpss_dev_type {
+	LPSS_DEV_I2C = 0,
+	LPSS_DEV_UART,
+	LPSS_DEV_SPI,
+};
+
+struct intel_lpss {
+	const struct intel_lpss_platform_info *info;
+	enum intel_lpss_dev_type type;
+	struct clk *clk;
+	struct clk_lookup *clock;
+	const struct mfd_cell *cell;
+	struct device *dev;
+	void __iomem *priv;
+	int devid;
+	u32 caps;
+	u32 active_ltr;
+	u32 idle_ltr;
+	struct dentry *debugfs;
+};
+
+static const struct resource intel_lpss_dev_resources[] = {
+	DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
+	DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
+	DEFINE_RES_IRQ(0),
+};
+
+static const struct resource intel_lpss_idma64_resources[] = {
+	DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
+	DEFINE_RES_IRQ(0),
+};
+
+#define LPSS_IDMA64_DRIVER_NAME		"idma64"
+
+/*
+ * Cells needs to be ordered so that the iDMA is created first. This is
+ * because we need to be sure the DMA is available when the host controller
+ * driver is probed.
+ */
+static const struct mfd_cell intel_lpss_idma64_cell = {
+	.name = LPSS_IDMA64_DRIVER_NAME,
+	.num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
+	.resources = intel_lpss_idma64_resources,
+};
+
+static const struct mfd_cell intel_lpss_i2c_cell = {
+	.name = "i2c_designware",
+	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
+	.resources = intel_lpss_dev_resources,
+};
+
+static const struct mfd_cell intel_lpss_uart_cell = {
+	.name = "dw-apb-uart",
+	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
+	.resources = intel_lpss_dev_resources,
+};
+
+static const struct mfd_cell intel_lpss_spi_cell = {
+	.name = "pxa2xx-spi",
+	.num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
+	.resources = intel_lpss_dev_resources,
+};
+
+static DEFINE_IDA(intel_lpss_devid_ida);
+static struct dentry *intel_lpss_debugfs;
+
+static int intel_lpss_request_dma_module(const char *name)
+{
+	static bool intel_lpss_dma_requested;
+
+	if (intel_lpss_dma_requested)
+		return 0;
+
+	intel_lpss_dma_requested = true;
+	return request_module("%s", name);
+}
+
+static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
+{
+	lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
+	lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
+}
+
+static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
+{
+	struct dentry *dir;
+
+	dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
+	if (IS_ERR(dir))
+		return PTR_ERR(dir);
+
+	/* Cache the values into lpss structure */
+	intel_lpss_cache_ltr(lpss);
+
+	debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
+	debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
+	debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
+
+	lpss->debugfs = dir;
+	return 0;
+}
+
+static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
+{
+	debugfs_remove_recursive(lpss->debugfs);
+}
+
+static void intel_lpss_ltr_set(struct device *dev, s32 val)
+{
+	struct intel_lpss *lpss = dev_get_drvdata(dev);
+	u32 ltr;
+
+	/*
+	 * Program latency tolerance (LTR) accordingly what has been asked
+	 * by the PM QoS layer or disable it in case we were passed
+	 * negative value or PM_QOS_LATENCY_ANY.
+	 */
+	ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
+
+	if (val == PM_QOS_LATENCY_ANY || val < 0) {
+		ltr &= ~LPSS_PRIV_LTR_REQ;
+	} else {
+		ltr |= LPSS_PRIV_LTR_REQ;
+		ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
+		ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
+
+		if (val > LPSS_PRIV_LTR_VALUE_MASK)
+			ltr |= LPSS_PRIV_LTR_SCALE_32US | val >> 5;
+		else
+			ltr |= LPSS_PRIV_LTR_SCALE_1US | val;
+	}
+
+	if (ltr == lpss->active_ltr)
+		return;
+
+	writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
+	writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
+
+	/* Cache the values into lpss structure */
+	intel_lpss_cache_ltr(lpss);
+}
+
+static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
+{
+	lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
+	dev_pm_qos_expose_latency_tolerance(lpss->dev);
+}
+
+static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
+{
+	dev_pm_qos_hide_latency_tolerance(lpss->dev);
+	lpss->dev->power.set_latency_tolerance = NULL;
+}
+
+static int intel_lpss_assign_devs(struct intel_lpss *lpss)
+{
+	unsigned int type;
+
+	type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
+	type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
+
+	switch (type) {
+	case LPSS_DEV_I2C:
+		lpss->cell = &intel_lpss_i2c_cell;
+		break;
+	case LPSS_DEV_UART:
+		lpss->cell = &intel_lpss_uart_cell;
+		break;
+	case LPSS_DEV_SPI:
+		lpss->cell = &intel_lpss_spi_cell;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	lpss->type = type;
+
+	return 0;
+}
+
+static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
+{
+	return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
+}
+
+static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
+{
+	resource_size_t addr = lpss->info->mem->start;
+
+	writel(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR_LO);
+#if BITS_PER_LONG > 32
+	writel(addr >> 32, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
+#else
+	writel(0, lpss->priv + LPSS_PRIV_REMAP_ADDR_HI);
+#endif
+}
+
+static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
+{
+	u32 value = LPSS_PRIV_RESETS_FUNC | LPSS_PRIV_RESETS_IDMA;
+
+	/* Bring out the device from reset */
+	writel(value, lpss->priv + LPSS_PRIV_RESETS);
+}
+
+static void intel_lpss_init_dev(const struct intel_lpss *lpss)
+{
+	u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
+
+	intel_lpss_deassert_reset(lpss);
+
+	if (!intel_lpss_has_idma(lpss))
+		return;
+
+	intel_lpss_set_remap_addr(lpss);
+
+	/* Make sure that SPI multiblock DMA transfers are re-enabled */
+	if (lpss->type == LPSS_DEV_SPI)
+		writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
+}
+
+static void intel_lpss_unregister_clock_tree(struct clk *clk)
+{
+	struct clk *parent;
+
+	while (clk) {
+		parent = clk_get_parent(clk);
+		clk_unregister(clk);
+		clk = parent;
+	}
+}
+
+static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
+					     const char *devname,
+					     struct clk **clk)
+{
+	char name[32];
+	struct clk *tmp = *clk;
+
+	snprintf(name, sizeof(name), "%s-enable", devname);
+	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
+				lpss->priv, 0, 0, NULL);
+	if (IS_ERR(tmp))
+		return PTR_ERR(tmp);
+
+	snprintf(name, sizeof(name), "%s-div", devname);
+	tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
+					      0, lpss->priv, 1, 15, 16, 15, 0,
+					      NULL);
+	if (IS_ERR(tmp))
+		return PTR_ERR(tmp);
+	*clk = tmp;
+
+	snprintf(name, sizeof(name), "%s-update", devname);
+	tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
+				CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
+	if (IS_ERR(tmp))
+		return PTR_ERR(tmp);
+	*clk = tmp;
+
+	return 0;
+}
+
+static int intel_lpss_register_clock(struct intel_lpss *lpss)
+{
+	const struct mfd_cell *cell = lpss->cell;
+	struct clk *clk;
+	char devname[24];
+	int ret;
+
+	if (!lpss->info->clk_rate)
+		return 0;
+
+	/* Root clock */
+	clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL,
+				      CLK_IS_ROOT, lpss->info->clk_rate);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
+
+	/*
+	 * Support for clock divider only if it has some preset value.
+	 * Otherwise we assume that the divider is not used.
+	 */
+	if (lpss->type != LPSS_DEV_I2C) {
+		ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
+		if (ret)
+			goto err_clk_register;
+	}
+
+	ret = -ENOMEM;
+
+	/* Clock for the host controller */
+	lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
+	if (!lpss->clock)
+		goto err_clk_register;
+
+	lpss->clk = clk;
+
+	return 0;
+
+err_clk_register:
+	intel_lpss_unregister_clock_tree(clk);
+
+	return ret;
+}
+
+static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
+{
+	if (IS_ERR_OR_NULL(lpss->clk))
+		return;
+
+	clkdev_drop(lpss->clock);
+	intel_lpss_unregister_clock_tree(lpss->clk);
+}
+
+int intel_lpss_probe(struct device *dev,
+		     const struct intel_lpss_platform_info *info)
+{
+	struct intel_lpss *lpss;
+	int ret;
+
+	if (!info || !info->mem || info->irq <= 0)
+		return -EINVAL;
+
+	lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
+	if (!lpss)
+		return -ENOMEM;
+
+	lpss->priv = devm_ioremap(dev, info->mem->start + LPSS_PRIV_OFFSET,
+				  LPSS_PRIV_SIZE);
+	if (!lpss->priv)
+		return -ENOMEM;
+
+	lpss->info = info;
+	lpss->dev = dev;
+	lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
+
+	dev_set_drvdata(dev, lpss);
+
+	ret = intel_lpss_assign_devs(lpss);
+	if (ret)
+		return ret;
+
+	intel_lpss_init_dev(lpss);
+
+	lpss->devid = ida_simple_get(&intel_lpss_devid_ida, 0, 0, GFP_KERNEL);
+	if (lpss->devid < 0)
+		return lpss->devid;
+
+	ret = intel_lpss_register_clock(lpss);
+	if (ret)
+		goto err_clk_register;
+
+	intel_lpss_ltr_expose(lpss);
+
+	ret = intel_lpss_debugfs_add(lpss);
+	if (ret)
+		dev_warn(dev, "Failed to create debugfs entries\n");
+
+	if (intel_lpss_has_idma(lpss)) {
+		/*
+		 * Ensure the DMA driver is loaded before the host
+		 * controller device appears, so that the host controller
+		 * driver can request its DMA channels as early as
+		 * possible.
+		 *
+		 * If the DMA module is not there that's OK as well.
+		 */
+		intel_lpss_request_dma_module(LPSS_IDMA64_DRIVER_NAME);
+
+		ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
+				      1, info->mem, info->irq, NULL);
+		if (ret)
+			dev_warn(dev, "Failed to add %s, fallback to PIO\n",
+				 LPSS_IDMA64_DRIVER_NAME);
+	}
+
+	ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
+			      1, info->mem, info->irq, NULL);
+	if (ret)
+		goto err_remove_ltr;
+
+	return 0;
+
+err_remove_ltr:
+	intel_lpss_debugfs_remove(lpss);
+	intel_lpss_ltr_hide(lpss);
+
+err_clk_register:
+	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(intel_lpss_probe);
+
+void intel_lpss_remove(struct device *dev)
+{
+	struct intel_lpss *lpss = dev_get_drvdata(dev);
+
+	mfd_remove_devices(dev);
+	intel_lpss_debugfs_remove(lpss);
+	intel_lpss_ltr_hide(lpss);
+	intel_lpss_unregister_clock(lpss);
+	ida_simple_remove(&intel_lpss_devid_ida, lpss->devid);
+}
+EXPORT_SYMBOL_GPL(intel_lpss_remove);
+
+static int resume_lpss_device(struct device *dev, void *data)
+{
+	pm_runtime_resume(dev);
+	return 0;
+}
+
+int intel_lpss_prepare(struct device *dev)
+{
+	/*
+	 * Resume both child devices before entering system sleep. This
+	 * ensures that they are in proper state before they get suspended.
+	 */
+	device_for_each_child_reverse(dev, NULL, resume_lpss_device);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_lpss_prepare);
+
+int intel_lpss_suspend(struct device *dev)
+{
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_lpss_suspend);
+
+int intel_lpss_resume(struct device *dev)
+{
+	struct intel_lpss *lpss = dev_get_drvdata(dev);
+
+	intel_lpss_init_dev(lpss);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(intel_lpss_resume);
+
+static int __init intel_lpss_init(void)
+{
+	intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
+	return 0;
+}
+module_init(intel_lpss_init);
+
+static void __exit intel_lpss_exit(void)
+{
+	debugfs_remove(intel_lpss_debugfs);
+}
+module_exit(intel_lpss_exit);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
+MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
+MODULE_DESCRIPTION("Intel LPSS core driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/mfd/intel-lpss.h b/drivers/mfd/intel-lpss.h
new file mode 100644
index 000000000000..f28cb28a62f8
--- /dev/null
+++ b/drivers/mfd/intel-lpss.h
@@ -0,0 +1,62 @@
+/*
+ * Intel LPSS core support.
+ *
+ * Copyright (C) 2015, Intel Corporation
+ *
+ * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __MFD_INTEL_LPSS_H
+#define __MFD_INTEL_LPSS_H
+
+struct device;
+struct resource;
+
+struct intel_lpss_platform_info {
+	struct resource *mem;
+	int irq;
+	unsigned long clk_rate;
+	const char *clk_con_id;
+};
+
+int intel_lpss_probe(struct device *dev,
+		     const struct intel_lpss_platform_info *info);
+void intel_lpss_remove(struct device *dev);
+
+#ifdef CONFIG_PM
+int intel_lpss_prepare(struct device *dev);
+int intel_lpss_suspend(struct device *dev);
+int intel_lpss_resume(struct device *dev);
+
+#ifdef CONFIG_PM_SLEEP
+#define INTEL_LPSS_SLEEP_PM_OPS			\
+	.prepare = intel_lpss_prepare,		\
+	.suspend = intel_lpss_suspend,		\
+	.resume = intel_lpss_resume,		\
+	.freeze = intel_lpss_suspend,		\
+	.thaw = intel_lpss_resume,		\
+	.poweroff = intel_lpss_suspend,		\
+	.restore = intel_lpss_resume,
+#endif
+
+#define INTEL_LPSS_RUNTIME_PM_OPS		\
+	.runtime_suspend = intel_lpss_suspend,	\
+	.runtime_resume = intel_lpss_resume,
+
+#else /* !CONFIG_PM */
+#define INTEL_LPSS_SLEEP_PM_OPS
+#define INTEL_LPSS_RUNTIME_PM_OPS
+#endif /* CONFIG_PM */
+
+#define INTEL_LPSS_PM_OPS(name)			\
+const struct dev_pm_ops name = {		\
+	INTEL_LPSS_SLEEP_PM_OPS			\
+	INTEL_LPSS_RUNTIME_PM_OPS		\
+}
+
+#endif /* __MFD_INTEL_LPSS_H */
diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
index 14fd5cbcf0f2..c17635d3e504 100644
--- a/drivers/mfd/mfd-core.c
+++ b/drivers/mfd/mfd-core.c
@@ -302,7 +302,7 @@ void mfd_remove_devices(struct device *parent)
 {
 	atomic_t *cnts = NULL;
 
-	device_for_each_child(parent, &cnts, mfd_remove_devices_fn);
+	device_for_each_child_reverse(parent, &cnts, mfd_remove_devices_fn);
 	kfree(cnts);
 }
 EXPORT_SYMBOL(mfd_remove_devices);
diff --git a/include/linux/device.h b/include/linux/device.h
index a2b4ea70a946..9d212fee4158 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -959,6 +959,8 @@ extern int __must_check device_add(struct device *dev);
 extern void device_del(struct device *dev);
 extern int device_for_each_child(struct device *dev, void *data,
 		     int (*fn)(struct device *dev, void *data));
+extern int device_for_each_child_reverse(struct device *dev, void *data,
+		     int (*fn)(struct device *dev, void *data));
 extern struct device *device_find_child(struct device *dev, void *data,
 				int (*match)(struct device *dev, void *data));
 extern int device_rename(struct device *dev, const char *new_name);
diff --git a/include/linux/klist.h b/include/linux/klist.h
index 61e5b723ae73..953f283f8451 100644
--- a/include/linux/klist.h
+++ b/include/linux/klist.h
@@ -63,6 +63,7 @@ extern void klist_iter_init(struct klist *k, struct klist_iter *i);
 extern void klist_iter_init_node(struct klist *k, struct klist_iter *i,
 				 struct klist_node *n);
 extern void klist_iter_exit(struct klist_iter *i);
+extern struct klist_node *klist_prev(struct klist_iter *i);
 extern struct klist_node *klist_next(struct klist_iter *i);
 
 #endif
diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 7b3ae0cffc05..0f65d36c2a75 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -161,6 +161,8 @@ void dev_pm_qos_hide_flags(struct device *dev);
 int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set);
 s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev);
 int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val);
+int dev_pm_qos_expose_latency_tolerance(struct device *dev);
+void dev_pm_qos_hide_latency_tolerance(struct device *dev);
 
 static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev)
 {
@@ -229,6 +231,9 @@ static inline s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev)
 			{ return PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; }
 static inline int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val)
 			{ return 0; }
+static inline int dev_pm_qos_expose_latency_tolerance(struct device *dev)
+			{ return 0; }
+static inline void dev_pm_qos_hide_latency_tolerance(struct device *dev) {}
 
 static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev) { return 0; }
 static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; }
diff --git a/lib/klist.c b/lib/klist.c
index 89b485a2a58d..d74cf7a29afd 100644
--- a/lib/klist.c
+++ b/lib/klist.c
@@ -324,6 +324,47 @@ static struct klist_node *to_klist_node(struct list_head *n)
 }
 
 /**
+ * klist_prev - Ante up prev node in list.
+ * @i: Iterator structure.
+ *
+ * First grab list lock. Decrement the reference count of the previous
+ * node, if there was one. Grab the prev node, increment its reference
+ * count, drop the lock, and return that prev node.
+ */
+struct klist_node *klist_prev(struct klist_iter *i)
+{
+	void (*put)(struct klist_node *) = i->i_klist->put;
+	struct klist_node *last = i->i_cur;
+	struct klist_node *prev;
+
+	spin_lock(&i->i_klist->k_lock);
+
+	if (last) {
+		prev = to_klist_node(last->n_node.prev);
+		if (!klist_dec_and_del(last))
+			put = NULL;
+	} else
+		prev = to_klist_node(i->i_klist->k_list.prev);
+
+	i->i_cur = NULL;
+	while (prev != to_klist_node(&i->i_klist->k_list)) {
+		if (likely(!knode_dead(prev))) {
+			kref_get(&prev->n_ref);
+			i->i_cur = prev;
+			break;
+		}
+		prev = to_klist_node(prev->n_node.prev);
+	}
+
+	spin_unlock(&i->i_klist->k_lock);
+
+	if (put && last)
+		put(last);
+	return i->i_cur;
+}
+EXPORT_SYMBOL_GPL(klist_prev);
+
+/**
  * klist_next - Ante up next node in list.
  * @i: Iterator structure.
  *