drivers/acpi/resource.c - kernel/msm-4.9 - Gitiles

 /*
  * 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.
  *
  *  You should have received a copy of the GNU General Public License along
  *  with this program; if not, write to the Free Software Foundation, Inc.,
  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */

 #include <linux/acpi.h>
 #include <linux/device.h>
 #include <linux/export.h>
 #include <linux/ioport.h>
 #include <linux/slab.h>

 #ifdef CONFIG_X86
 #define valid_IRQ(i) (((i) != 0) && ((i) != 2))
 #else
 #define valid_IRQ(i) (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.
 	 */
 	if (len && reslen && reslen == len && 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)
 {
 	res->flags = IORESOURCE_IO;

 	if (!acpi_dev_resource_len_valid(res->start, res->end, len, true))
 		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;

 	if (res->end >= 0x10003)
 		res->flags |= IORESOURCE_DISABLED | IORESOURCE_UNSET;

 	if (io_decode == ACPI_DECODE_16)
 		res->flags |= IORESOURCE_IO_16BIT_ADDR;
 }

 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);
 }

 /**
  * 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;
 	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);

 	res->start = attr->minimum;
 	res->end = attr->maximum;

 	/*
 	 * 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) {
 		res->start += attr->translation_offset;
 		res->end += attr->translation_offset;
 	} else if (attr->translation_offset) {
 		pr_debug("ACPI: translation_offset(%lld) is invalid for non-bridge device.\n",
 			 attr->translation_offset);
 	}

 	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);
 		break;
 	case ACPI_BUS_NUMBER_RANGE:
 		res->flags = IORESOURCE_BUS;
 		break;
 	default:
 		return false;
 	}

 	win->offset = attr->translation_offset;

 	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);

 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 overrided 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;
 		}
 		acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
 					 ext_irq->triggering, ext_irq->polarity,
 					 ext_irq->sharable, false);
 		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_CTRL_TERMINATE;
 		} 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;
 }

 /**
  * 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)
 {
 	struct res_proc_context c;
 	acpi_status status;

 	if (!adev || !adev->handle || !list_empty(list))
 		return -EINVAL;

 	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS))
 		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_NAME__CRS,
 				     acpi_dev_process_resource, &c);
 	if (ACPI_FAILURE(status)) {
 		acpi_dev_free_resource_list(list);
 		return c.error ? c.error : -EIO;
 	}

 	return c.count;
 }
 EXPORT_SYMBOL_GPL(acpi_dev_get_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 hepler 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);
	/*
	* 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.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, write to the Free Software Foundation, Inc.,
	* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
	*
	* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	*/

	#include <linux/acpi.h>
	#include <linux/device.h>
	#include <linux/export.h>
	#include <linux/ioport.h>
	#include <linux/slab.h>

	#ifdef CONFIG_X86
	#define valid_IRQ(i) (((i) != 0) && ((i) != 2))
	#else
	#define valid_IRQ(i) (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.
	*/
	if (len && reslen && reslen == len && 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)
	{
	res->flags = IORESOURCE_IO;

	if (!acpi_dev_resource_len_valid(res->start, res->end, len, true))
	res->flags \|= IORESOURCE_DISABLED \| IORESOURCE_UNSET;

	if (res->end >= 0x10003)
	res->flags \|= IORESOURCE_DISABLED \| IORESOURCE_UNSET;

	if (io_decode == ACPI_DECODE_16)
	res->flags \|= IORESOURCE_IO_16BIT_ADDR;
	}

	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);
	}

	/**
	* 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;
	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);

	res->start = attr->minimum;
	res->end = attr->maximum;

	/*
	* 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) {
	res->start += attr->translation_offset;
	res->end += attr->translation_offset;
	} else if (attr->translation_offset) {
	pr_debug("ACPI: translation_offset(%lld) is invalid for non-bridge device.\n",
	attr->translation_offset);
	}

	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);
	break;
	case ACPI_BUS_NUMBER_RANGE:
	res->flags = IORESOURCE_BUS;
	break;
	default:
	return false;
	}

	win->offset = attr->translation_offset;

	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);

	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 overrided 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;
	}
	acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
	ext_irq->triggering, ext_irq->polarity,
	ext_irq->sharable, false);
	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_CTRL_TERMINATE;
	} 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;
	}

	/**
	* 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)
	{
	struct res_proc_context c;
	acpi_status status;

	if (!adev \|\| !adev->handle \|\| !list_empty(list))
	return -EINVAL;

	if (!acpi_has_method(adev->handle, METHOD_NAME__CRS))
	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_NAME__CRS,
	acpi_dev_process_resource, &c);
	if (ACPI_FAILURE(status)) {
	acpi_dev_free_resource_list(list);
	return c.error ? c.error : -EIO;
	}

	return c.count;
	}
	EXPORT_SYMBOL_GPL(acpi_dev_get_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 hepler 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);