Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 784 insertions, 0 deletions

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
new file mode 100644
index 000000000..d3f9a320e
--- /dev/null
+++ b/drivers/acpi/resource.c
@@ -0,0 +1,784 @@
+/*
+ * drivers/acpi/resource.c - ACPI device resources interpretation.
+ *
+ * Copyright (C) 2012, Intel Corp.
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@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.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+
+#ifdef CONFIG_X86
+#define valid_IRQ(i) (((i) != 0) && ((i) != 2))
+static inline bool acpi_iospace_resource_valid(struct resource *res)
+{
+	/* On X86 IO space is limited to the [0 - 64K] IO port range */
+	return res->end < 0x10003;
+}
+#else
+#define valid_IRQ(i) (true)
+/*
+ * ACPI IO descriptors on arches other than X86 contain MMIO CPU physical
+ * addresses mapping IO space in CPU physical address space, IO space
+ * resources can be placed anywhere in the 64-bit physical address space.
+ */
+static inline bool
+acpi_iospace_resource_valid(struct resource *res) { return true; }
+#endif
+
+#if IS_ENABLED(CONFIG_ACPI_GENERIC_GSI)
+static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
+{
+	return ext_irq->resource_source.string_length == 0 &&
+	       ext_irq->producer_consumer == ACPI_CONSUMER;
+}
+#else
+static inline bool is_gsi(struct acpi_resource_extended_irq *ext_irq)
+{
+	return true;
+}
+#endif
+
+static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
+{
+	u64 reslen = end - start + 1;
+
+	/*
+	 * CHECKME: len might be required to check versus a minimum
+	 * length as well. 1 for io is fine, but for memory it does
+	 * not make any sense at all.
+	 * Note: some BIOSes report incorrect length for ACPI address space
+	 * descriptor, so remove check of 'reslen == len' to avoid regression.
+	 */
+	if (len && reslen && start <= end)
+		return true;
+
+	pr_debug("ACPI: invalid or unassigned resource %s [%016llx - %016llx] length [%016llx]\n",
+		io ? "io" : "mem", start, end, len);
+
+	return false;
+}
+
+static void acpi_dev_memresource_flags(struct resource *res, u64 len,
+				       u8 write_protect)
+{
+	res->flags = IORESOURCE_MEM;
+
+	if (!acpi_dev_resource_len_valid(res->start, res->end, len, false))
+		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;
+
+	if (write_protect == ACPI_READ_WRITE_MEMORY)
+		res->flags |= IORESOURCE_MEM_WRITEABLE;
+}
+
+static void acpi_dev_get_memresource(struct resource *res, u64 start, u64 len,
+				     u8 write_protect)
+{
+	res->start = start;
+	res->end = start + len - 1;
+	acpi_dev_memresource_flags(res, len, write_protect);
+}
+
+/**
+ * acpi_dev_resource_memory - Extract ACPI memory resource information.
+ * @ares: Input ACPI resource object.
+ * @res: Output generic resource object.
+ *
+ * Check if the given ACPI resource object represents a memory resource and
+ * if that's the case, use the information in it to populate the generic
+ * resource object pointed to by @res.
+ *
+ * Return:
+ * 1) false with res->flags setting to zero: not the expected resource type
+ * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
+ * 3) true: valid assigned resource
+ */
+bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res)
+{
+	struct acpi_resource_memory24 *memory24;
+	struct acpi_resource_memory32 *memory32;
+	struct acpi_resource_fixed_memory32 *fixed_memory32;
+
+	switch (ares->type) {
+	case ACPI_RESOURCE_TYPE_MEMORY24:
+		memory24 = &ares->data.memory24;
+		acpi_dev_get_memresource(res, memory24->minimum << 8,
+					 memory24->address_length << 8,
+					 memory24->write_protect);
+		break;
+	case ACPI_RESOURCE_TYPE_MEMORY32:
+		memory32 = &ares->data.memory32;
+		acpi_dev_get_memresource(res, memory32->minimum,
+					 memory32->address_length,
+					 memory32->write_protect);
+		break;
+	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
+		fixed_memory32 = &ares->data.fixed_memory32;
+		acpi_dev_get_memresource(res, fixed_memory32->address,
+					 fixed_memory32->address_length,
+					 fixed_memory32->write_protect);
+		break;
+	default:
+		res->flags = 0;
+		return false;
+	}
+
+	return !(res->flags & IORESOURCE_DISABLED);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_resource_memory);
+
+static void acpi_dev_ioresource_flags(struct resource *res, u64 len,
+				      u8 io_decode, u8 translation_type)
+{
+	res->flags = IORESOURCE_IO;
+
+	if (!acpi_dev_resource_len_valid(res->start, res->end, len, true))
+		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;
+
+	if (!acpi_iospace_resource_valid(res))
+		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;
+
+	if (io_decode == ACPI_DECODE_16)
+		res->flags |= IORESOURCE_IO_16BIT_ADDR;
+	if (translation_type == ACPI_SPARSE_TRANSLATION)
+		res->flags |= IORESOURCE_IO_SPARSE;
+}
+
+static void acpi_dev_get_ioresource(struct resource *res, u64 start, u64 len,
+				    u8 io_decode)
+{
+	res->start = start;
+	res->end = start + len - 1;
+	acpi_dev_ioresource_flags(res, len, io_decode, 0);
+}
+
+/**
+ * acpi_dev_resource_io - Extract ACPI I/O resource information.
+ * @ares: Input ACPI resource object.
+ * @res: Output generic resource object.
+ *
+ * Check if the given ACPI resource object represents an I/O resource and
+ * if that's the case, use the information in it to populate the generic
+ * resource object pointed to by @res.
+ *
+ * Return:
+ * 1) false with res->flags setting to zero: not the expected resource type
+ * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
+ * 3) true: valid assigned resource
+ */
+bool acpi_dev_resource_io(struct acpi_resource *ares, struct resource *res)
+{
+	struct acpi_resource_io *io;
+	struct acpi_resource_fixed_io *fixed_io;
+
+	switch (ares->type) {
+	case ACPI_RESOURCE_TYPE_IO:
+		io = &ares->data.io;
+		acpi_dev_get_ioresource(res, io->minimum,
+					io->address_length,
+					io->io_decode);
+		break;
+	case ACPI_RESOURCE_TYPE_FIXED_IO:
+		fixed_io = &ares->data.fixed_io;
+		acpi_dev_get_ioresource(res, fixed_io->address,
+					fixed_io->address_length,
+					ACPI_DECODE_10);
+		break;
+	default:
+		res->flags = 0;
+		return false;
+	}
+
+	return !(res->flags & IORESOURCE_DISABLED);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_resource_io);
+
+static bool acpi_decode_space(struct resource_win *win,
+			      struct acpi_resource_address *addr,
+			      struct acpi_address64_attribute *attr)
+{
+	u8 iodec = attr->granularity == 0xfff ? ACPI_DECODE_10 : ACPI_DECODE_16;
+	bool wp = addr->info.mem.write_protect;
+	u64 len = attr->address_length;
+	u64 start, end, offset = 0;
+	struct resource *res = &win->res;
+
+	/*
+	 * Filter out invalid descriptor according to ACPI Spec 5.0, section
+	 * 6.4.3.5 Address Space Resource Descriptors.
+	 */
+	if ((addr->min_address_fixed != addr->max_address_fixed && len) ||
+	    (addr->min_address_fixed && addr->max_address_fixed && !len))
+		pr_debug("ACPI: Invalid address space min_addr_fix %d, max_addr_fix %d, len %llx\n",
+			 addr->min_address_fixed, addr->max_address_fixed, len);
+
+	/*
+	 * For bridges that translate addresses across the bridge,
+	 * translation_offset is the offset that must be added to the
+	 * address on the secondary side to obtain the address on the
+	 * primary side. Non-bridge devices must list 0 for all Address
+	 * Translation offset bits.
+	 */
+	if (addr->producer_consumer == ACPI_PRODUCER)
+		offset = attr->translation_offset;
+	else if (attr->translation_offset)
+		pr_debug("ACPI: translation_offset(%lld) is invalid for non-bridge device.\n",
+			 attr->translation_offset);
+	start = attr->minimum + offset;
+	end = attr->maximum + offset;
+
+	win->offset = offset;
+	res->start = start;
+	res->end = end;
+	if (sizeof(resource_size_t) < sizeof(u64) &&
+	    (offset != win->offset || start != res->start || end != res->end)) {
+		pr_warn("acpi resource window ([%#llx-%#llx] ignored, not CPU addressable)\n",
+			attr->minimum, attr->maximum);
+		return false;
+	}
+
+	switch (addr->resource_type) {
+	case ACPI_MEMORY_RANGE:
+		acpi_dev_memresource_flags(res, len, wp);
+		break;
+	case ACPI_IO_RANGE:
+		acpi_dev_ioresource_flags(res, len, iodec,
+					  addr->info.io.translation_type);
+		break;
+	case ACPI_BUS_NUMBER_RANGE:
+		res->flags = IORESOURCE_BUS;
+		break;
+	default:
+		return false;
+	}
+
+	if (addr->producer_consumer == ACPI_PRODUCER)
+		res->flags |= IORESOURCE_WINDOW;
+
+	if (addr->info.mem.caching == ACPI_PREFETCHABLE_MEMORY)
+		res->flags |= IORESOURCE_PREFETCH;
+
+	return !(res->flags & IORESOURCE_DISABLED);
+}
+
+/**
+ * acpi_dev_resource_address_space - Extract ACPI address space information.
+ * @ares: Input ACPI resource object.
+ * @win: Output generic resource object.
+ *
+ * Check if the given ACPI resource object represents an address space resource
+ * and if that's the case, use the information in it to populate the generic
+ * resource object pointed to by @win.
+ *
+ * Return:
+ * 1) false with win->res.flags setting to zero: not the expected resource type
+ * 2) false with IORESOURCE_DISABLED in win->res.flags: valid unassigned
+ *    resource
+ * 3) true: valid assigned resource
+ */
+bool acpi_dev_resource_address_space(struct acpi_resource *ares,
+				     struct resource_win *win)
+{
+	struct acpi_resource_address64 addr;
+
+	win->res.flags = 0;
+	if (ACPI_FAILURE(acpi_resource_to_address64(ares, &addr)))
+		return false;
+
+	return acpi_decode_space(win, (struct acpi_resource_address *)&addr,
+				 &addr.address);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_resource_address_space);
+
+/**
+ * acpi_dev_resource_ext_address_space - Extract ACPI address space information.
+ * @ares: Input ACPI resource object.
+ * @win: Output generic resource object.
+ *
+ * Check if the given ACPI resource object represents an extended address space
+ * resource and if that's the case, use the information in it to populate the
+ * generic resource object pointed to by @win.
+ *
+ * Return:
+ * 1) false with win->res.flags setting to zero: not the expected resource type
+ * 2) false with IORESOURCE_DISABLED in win->res.flags: valid unassigned
+ *    resource
+ * 3) true: valid assigned resource
+ */
+bool acpi_dev_resource_ext_address_space(struct acpi_resource *ares,
+					 struct resource_win *win)
+{
+	struct acpi_resource_extended_address64 *ext_addr;
+
+	win->res.flags = 0;
+	if (ares->type != ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64)
+		return false;
+
+	ext_addr = &ares->data.ext_address64;
+
+	return acpi_decode_space(win, (struct acpi_resource_address *)ext_addr,
+				 &ext_addr->address);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_resource_ext_address_space);
+
+/**
+ * acpi_dev_irq_flags - Determine IRQ resource flags.
+ * @triggering: Triggering type as provided by ACPI.
+ * @polarity: Interrupt polarity as provided by ACPI.
+ * @shareable: Whether or not the interrupt is shareable.
+ */
+unsigned long acpi_dev_irq_flags(u8 triggering, u8 polarity, u8 shareable)
+{
+	unsigned long flags;
+
+	if (triggering == ACPI_LEVEL_SENSITIVE)
+		flags = polarity == ACPI_ACTIVE_LOW ?
+			IORESOURCE_IRQ_LOWLEVEL : IORESOURCE_IRQ_HIGHLEVEL;
+	else
+		flags = polarity == ACPI_ACTIVE_LOW ?
+			IORESOURCE_IRQ_LOWEDGE : IORESOURCE_IRQ_HIGHEDGE;
+
+	if (shareable == ACPI_SHARED)
+		flags |= IORESOURCE_IRQ_SHAREABLE;
+
+	return flags | IORESOURCE_IRQ;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_irq_flags);
+
+/**
+ * acpi_dev_get_irq_type - Determine irq type.
+ * @triggering: Triggering type as provided by ACPI.
+ * @polarity: Interrupt polarity as provided by ACPI.
+ */
+unsigned int acpi_dev_get_irq_type(int triggering, int polarity)
+{
+	switch (polarity) {
+	case ACPI_ACTIVE_LOW:
+		return triggering == ACPI_EDGE_SENSITIVE ?
+		       IRQ_TYPE_EDGE_FALLING :
+		       IRQ_TYPE_LEVEL_LOW;
+	case ACPI_ACTIVE_HIGH:
+		return triggering == ACPI_EDGE_SENSITIVE ?
+		       IRQ_TYPE_EDGE_RISING :
+		       IRQ_TYPE_LEVEL_HIGH;
+	case ACPI_ACTIVE_BOTH:
+		if (triggering == ACPI_EDGE_SENSITIVE)
+			return IRQ_TYPE_EDGE_BOTH;
+		/* fall through */
+	default:
+		return IRQ_TYPE_NONE;
+	}
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_irq_type);
+
+static void acpi_dev_irqresource_disabled(struct resource *res, u32 gsi)
+{
+	res->start = gsi;
+	res->end = gsi;
+	res->flags = IORESOURCE_IRQ | IORESOURCE_DISABLED | IORESOURCE_UNSET;
+}
+
+static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
+				     u8 triggering, u8 polarity, u8 shareable,
+				     bool legacy)
+{
+	int irq, p, t;
+
+	if (!valid_IRQ(gsi)) {
+		acpi_dev_irqresource_disabled(res, gsi);
+		return;
+	}
+
+	/*
+	 * In IO-APIC mode, use overridden attribute. Two reasons:
+	 * 1. BIOS bug in DSDT
+	 * 2. BIOS uses IO-APIC mode Interrupt Source Override
+	 *
+	 * We do this only if we are dealing with IRQ() or IRQNoFlags()
+	 * resource (the legacy ISA resources). With modern ACPI 5 devices
+	 * using extended IRQ descriptors we take the IRQ configuration
+	 * from _CRS directly.
+	 */
+	if (legacy && !acpi_get_override_irq(gsi, &t, &p)) {
+		u8 trig = t ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
+		u8 pol = p ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
+
+		if (triggering != trig || polarity != pol) {
+			pr_warning("ACPI: IRQ %d override to %s, %s\n", gsi,
+				   t ? "level" : "edge", p ? "low" : "high");
+			triggering = trig;
+			polarity = pol;
+		}
+	}
+
+	res->flags = acpi_dev_irq_flags(triggering, polarity, shareable);
+	irq = acpi_register_gsi(NULL, gsi, triggering, polarity);
+	if (irq >= 0) {
+		res->start = irq;
+		res->end = irq;
+	} else {
+		acpi_dev_irqresource_disabled(res, gsi);
+	}
+}
+
+/**
+ * acpi_dev_resource_interrupt - Extract ACPI interrupt resource information.
+ * @ares: Input ACPI resource object.
+ * @index: Index into the array of GSIs represented by the resource.
+ * @res: Output generic resource object.
+ *
+ * Check if the given ACPI resource object represents an interrupt resource
+ * and @index does not exceed the resource's interrupt count (true is returned
+ * in that case regardless of the results of the other checks)).  If that's the
+ * case, register the GSI corresponding to @index from the array of interrupts
+ * represented by the resource and populate the generic resource object pointed
+ * to by @res accordingly.  If the registration of the GSI is not successful,
+ * IORESOURCE_DISABLED will be set it that object's flags.
+ *
+ * Return:
+ * 1) false with res->flags setting to zero: not the expected resource type
+ * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
+ * 3) true: valid assigned resource
+ */
+bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
+				 struct resource *res)
+{
+	struct acpi_resource_irq *irq;
+	struct acpi_resource_extended_irq *ext_irq;
+
+	switch (ares->type) {
+	case ACPI_RESOURCE_TYPE_IRQ:
+		/*
+		 * Per spec, only one interrupt per descriptor is allowed in
+		 * _CRS, but some firmware violates this, so parse them all.
+		 */
+		irq = &ares->data.irq;
+		if (index >= irq->interrupt_count) {
+			acpi_dev_irqresource_disabled(res, 0);
+			return false;
+		}
+		acpi_dev_get_irqresource(res, irq->interrupts[index],
+					 irq->triggering, irq->polarity,
+					 irq->sharable, true);
+		break;
+	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+		ext_irq = &ares->data.extended_irq;
+		if (index >= ext_irq->interrupt_count) {
+			acpi_dev_irqresource_disabled(res, 0);
+			return false;
+		}
+		if (is_gsi(ext_irq))
+			acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
+					 ext_irq->triggering, ext_irq->polarity,
+					 ext_irq->sharable, false);
+		else
+			acpi_dev_irqresource_disabled(res, 0);
+		break;
+	default:
+		res->flags = 0;
+		return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_resource_interrupt);
+
+/**
+ * acpi_dev_free_resource_list - Free resource from %acpi_dev_get_resources().
+ * @list: The head of the resource list to free.
+ */
+void acpi_dev_free_resource_list(struct list_head *list)
+{
+	resource_list_free(list);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_free_resource_list);
+
+struct res_proc_context {
+	struct list_head *list;
+	int (*preproc)(struct acpi_resource *, void *);
+	void *preproc_data;
+	int count;
+	int error;
+};
+
+static acpi_status acpi_dev_new_resource_entry(struct resource_win *win,
+					       struct res_proc_context *c)
+{
+	struct resource_entry *rentry;
+
+	rentry = resource_list_create_entry(NULL, 0);
+	if (!rentry) {
+		c->error = -ENOMEM;
+		return AE_NO_MEMORY;
+	}
+	*rentry->res = win->res;
+	rentry->offset = win->offset;
+	resource_list_add_tail(rentry, c->list);
+	c->count++;
+	return AE_OK;
+}
+
+static acpi_status acpi_dev_process_resource(struct acpi_resource *ares,
+					     void *context)
+{
+	struct res_proc_context *c = context;
+	struct resource_win win;
+	struct resource *res = &win.res;
+	int i;
+
+	if (c->preproc) {
+		int ret;
+
+		ret = c->preproc(ares, c->preproc_data);
+		if (ret < 0) {
+			c->error = ret;
+			return AE_ABORT_METHOD;
+		} else if (ret > 0) {
+			return AE_OK;
+		}
+	}
+
+	memset(&win, 0, sizeof(win));
+
+	if (acpi_dev_resource_memory(ares, res)
+	    || acpi_dev_resource_io(ares, res)
+	    || acpi_dev_resource_address_space(ares, &win)
+	    || acpi_dev_resource_ext_address_space(ares, &win))
+		return acpi_dev_new_resource_entry(&win, c);
+
+	for (i = 0; acpi_dev_resource_interrupt(ares, i, res); i++) {
+		acpi_status status;
+
+		status = acpi_dev_new_resource_entry(&win, c);
+		if (ACPI_FAILURE(status))
+			return status;
+	}
+
+	return AE_OK;
+}
+
+static int __acpi_dev_get_resources(struct acpi_device *adev,
+				    struct list_head *list,
+				    int (*preproc)(struct acpi_resource *, void *),
+				    void *preproc_data, char *method)
+{
+	struct res_proc_context c;
+	acpi_status status;
+
+	if (!adev || !adev->handle || !list_empty(list))
+		return -EINVAL;
+
+	if (!acpi_has_method(adev->handle, method))
+		return 0;
+
+	c.list = list;
+	c.preproc = preproc;
+	c.preproc_data = preproc_data;
+	c.count = 0;
+	c.error = 0;
+	status = acpi_walk_resources(adev->handle, method,
+				     acpi_dev_process_resource, &c);
+	if (ACPI_FAILURE(status)) {
+		acpi_dev_free_resource_list(list);
+		return c.error ? c.error : -EIO;
+	}
+
+	return c.count;
+}
+
+/**
+ * acpi_dev_get_resources - Get current resources of a device.
+ * @adev: ACPI device node to get the resources for.
+ * @list: Head of the resultant list of resources (must be empty).
+ * @preproc: The caller's preprocessing routine.
+ * @preproc_data: Pointer passed to the caller's preprocessing routine.
+ *
+ * Evaluate the _CRS method for the given device node and process its output by
+ * (1) executing the @preproc() rountine provided by the caller, passing the
+ * resource pointer and @preproc_data to it as arguments, for each ACPI resource
+ * returned and (2) converting all of the returned ACPI resources into struct
+ * resource objects if possible.  If the return value of @preproc() in step (1)
+ * is different from 0, step (2) is not applied to the given ACPI resource and
+ * if that value is negative, the whole processing is aborted and that value is
+ * returned as the final error code.
+ *
+ * The resultant struct resource objects are put on the list pointed to by
+ * @list, that must be empty initially, as members of struct resource_entry
+ * objects.  Callers of this routine should use %acpi_dev_free_resource_list() to
+ * free that list.
+ *
+ * The number of resources in the output list is returned on success, an error
+ * code reflecting the error condition is returned otherwise.
+ */
+int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
+			   int (*preproc)(struct acpi_resource *, void *),
+			   void *preproc_data)
+{
+	return __acpi_dev_get_resources(adev, list, preproc, preproc_data,
+					METHOD_NAME__CRS);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_resources);
+
+static int is_memory(struct acpi_resource *ares, void *not_used)
+{
+	struct resource_win win;
+	struct resource *res = &win.res;
+
+	memset(&win, 0, sizeof(win));
+
+	return !(acpi_dev_resource_memory(ares, res)
+	       || acpi_dev_resource_address_space(ares, &win)
+	       || acpi_dev_resource_ext_address_space(ares, &win));
+}
+
+/**
+ * acpi_dev_get_dma_resources - Get current DMA resources of a device.
+ * @adev: ACPI device node to get the resources for.
+ * @list: Head of the resultant list of resources (must be empty).
+ *
+ * Evaluate the _DMA method for the given device node and process its
+ * output.
+ *
+ * The resultant struct resource objects are put on the list pointed to
+ * by @list, that must be empty initially, as members of struct
+ * resource_entry objects.  Callers of this routine should use
+ * %acpi_dev_free_resource_list() to free that list.
+ *
+ * The number of resources in the output list is returned on success,
+ * an error code reflecting the error condition is returned otherwise.
+ */
+int acpi_dev_get_dma_resources(struct acpi_device *adev, struct list_head *list)
+{
+	return __acpi_dev_get_resources(adev, list, is_memory, NULL,
+					METHOD_NAME__DMA);
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_dma_resources);
+
+/**
+ * acpi_dev_filter_resource_type - Filter ACPI resource according to resource
+ *				   types
+ * @ares: Input ACPI resource object.
+ * @types: Valid resource types of IORESOURCE_XXX
+ *
+ * This is a helper function to support acpi_dev_get_resources(), which filters
+ * ACPI resource objects according to resource types.
+ */
+int acpi_dev_filter_resource_type(struct acpi_resource *ares,
+				  unsigned long types)
+{
+	unsigned long type = 0;
+
+	switch (ares->type) {
+	case ACPI_RESOURCE_TYPE_MEMORY24:
+	case ACPI_RESOURCE_TYPE_MEMORY32:
+	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
+		type = IORESOURCE_MEM;
+		break;
+	case ACPI_RESOURCE_TYPE_IO:
+	case ACPI_RESOURCE_TYPE_FIXED_IO:
+		type = IORESOURCE_IO;
+		break;
+	case ACPI_RESOURCE_TYPE_IRQ:
+	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+		type = IORESOURCE_IRQ;
+		break;
+	case ACPI_RESOURCE_TYPE_DMA:
+	case ACPI_RESOURCE_TYPE_FIXED_DMA:
+		type = IORESOURCE_DMA;
+		break;
+	case ACPI_RESOURCE_TYPE_GENERIC_REGISTER:
+		type = IORESOURCE_REG;
+		break;
+	case ACPI_RESOURCE_TYPE_ADDRESS16:
+	case ACPI_RESOURCE_TYPE_ADDRESS32:
+	case ACPI_RESOURCE_TYPE_ADDRESS64:
+	case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
+		if (ares->data.address.resource_type == ACPI_MEMORY_RANGE)
+			type = IORESOURCE_MEM;
+		else if (ares->data.address.resource_type == ACPI_IO_RANGE)
+			type = IORESOURCE_IO;
+		else if (ares->data.address.resource_type ==
+			 ACPI_BUS_NUMBER_RANGE)
+			type = IORESOURCE_BUS;
+		break;
+	default:
+		break;
+	}
+
+	return (type & types) ? 0 : 1;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_filter_resource_type);
+
+static int acpi_dev_consumes_res(struct acpi_device *adev, struct resource *res)
+{
+	struct list_head resource_list;
+	struct resource_entry *rentry;
+	int ret, found = 0;
+
+	INIT_LIST_HEAD(&resource_list);
+	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
+	if (ret < 0)
+		return 0;
+
+	list_for_each_entry(rentry, &resource_list, node) {
+		if (resource_contains(rentry->res, res)) {
+			found = 1;
+			break;
+		}
+
+	}
+
+	acpi_dev_free_resource_list(&resource_list);
+	return found;
+}
+
+static acpi_status acpi_res_consumer_cb(acpi_handle handle, u32 depth,
+					 void *context, void **ret)
+{
+	struct resource *res = context;
+	struct acpi_device **consumer = (struct acpi_device **) ret;
+	struct acpi_device *adev;
+
+	if (acpi_bus_get_device(handle, &adev))
+		return AE_OK;
+
+	if (acpi_dev_consumes_res(adev, res)) {
+		*consumer = adev;
+		return AE_CTRL_TERMINATE;
+	}
+
+	return AE_OK;
+}
+
+/**
+ * acpi_resource_consumer - Find the ACPI device that consumes @res.
+ * @res: Resource to search for.
+ *
+ * Search the current resource settings (_CRS) of every ACPI device node
+ * for @res.  If we find an ACPI device whose _CRS includes @res, return
+ * it.  Otherwise, return NULL.
+ */
+struct acpi_device *acpi_resource_consumer(struct resource *res)
+{
+	struct acpi_device *consumer = NULL;
+
+	acpi_get_devices(NULL, acpi_res_consumer_cb, res, (void **) &consumer);
+	return consumer;
+}