// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   * VME Bridge Framework
   *

   * Author: Martyn Welch <martyn.welch@ge.com>
   * Copyright 2008 GE Intelligent Platforms Embedded Systems, Inc.

   *
   * Based on work by Tom Armistead and Ajit Prem
   * Copyright 2004 Motorola Inc.

   */

  #include <linux/init.h>
  #include <linux/export.h>

  #include <linux/mm.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/pci.h>
  #include <linux/poll.h>
  #include <linux/highmem.h>
  #include <linux/interrupt.h>
  #include <linux/pagemap.h>
  #include <linux/device.h>
  #include <linux/dma-mapping.h>
  #include <linux/syscalls.h>

  #include <linux/mutex.h>

  #include <linux/spinlock.h>

  #include <linux/slab.h>

  #include <linux/vme.h>

  #include "vme_bridge.h"

  /* Bitmask and list of registered buses both protected by common mutex */

  static unsigned int vme_bus_numbers;

  static LIST_HEAD(vme_bus_list);
  static DEFINE_MUTEX(vme_buses_lock);

  static int __init vme_init(void);

  static struct vme_dev *dev_to_vme_dev(struct device *dev)

  {

  	return container_of(dev, struct vme_dev, dev);

  }
  
  /*
   * Find the bridge that the resource is associated with.
   */
  static struct vme_bridge *find_bridge(struct vme_resource *resource)
  {
  	/* Get list to search */
  	switch (resource->type) {
  	case VME_MASTER:
  		return list_entry(resource->entry, struct vme_master_resource,
  			list)->parent;
  		break;
  	case VME_SLAVE:
  		return list_entry(resource->entry, struct vme_slave_resource,
  			list)->parent;
  		break;
  	case VME_DMA:
  		return list_entry(resource->entry, struct vme_dma_resource,
  			list)->parent;
  		break;

  	case VME_LM:
  		return list_entry(resource->entry, struct vme_lm_resource,
  			list)->parent;
  		break;

  	default:
  		printk(KERN_ERR "Unknown resource type
  ");
  		return NULL;
  		break;
  	}
  }

  /**
   * vme_free_consistent - Allocate contiguous memory.
   * @resource: Pointer to VME resource.
   * @size: Size of allocation required.
   * @dma: Pointer to variable to store physical address of allocation.
   *

   * Allocate a contiguous block of memory for use by the driver. This is used to
   * create the buffers for the slave windows.

   *
   * Return: Virtual address of allocation on success, NULL on failure.

   */

  void *vme_alloc_consistent(struct vme_resource *resource, size_t size,

  	dma_addr_t *dma)
  {
  	struct vme_bridge *bridge;

  	if (!resource) {

  		printk(KERN_ERR "No resource
  ");

  		return NULL;
  	}
  
  	bridge = find_bridge(resource);

  	if (!bridge) {

  		printk(KERN_ERR "Can't find bridge
  ");

  		return NULL;
  	}

  	if (!bridge->parent) {

  		printk(KERN_ERR "Dev entry NULL for bridge %s
  ", bridge->name);

  		return NULL;
  	}

  	if (!bridge->alloc_consistent) {

  		printk(KERN_ERR "alloc_consistent not supported by bridge %s
  ",
  		       bridge->name);

  		return NULL;
  	}

  	return bridge->alloc_consistent(bridge->parent, size, dma);

  }
  EXPORT_SYMBOL(vme_alloc_consistent);

  /**
   * vme_free_consistent - Free previously allocated memory.
   * @resource: Pointer to VME resource.
   * @size: Size of allocation to free.
   * @vaddr: Virtual address of allocation.
   * @dma: Physical address of allocation.
   *
   * Free previously allocated block of contiguous memory.

   */
  void vme_free_consistent(struct vme_resource *resource, size_t size,
  	void *vaddr, dma_addr_t dma)
  {
  	struct vme_bridge *bridge;

  	if (!resource) {

  		printk(KERN_ERR "No resource
  ");

  		return;
  	}
  
  	bridge = find_bridge(resource);

  	if (!bridge) {

  		printk(KERN_ERR "Can't find bridge
  ");

  		return;
  	}

  	if (!bridge->parent) {

  		printk(KERN_ERR "Dev entry NULL for bridge %s
  ", bridge->name);

  		return;
  	}

  	if (!bridge->free_consistent) {

  		printk(KERN_ERR "free_consistent not supported by bridge %s
  ",
  		       bridge->name);

  		return;
  	}

  	bridge->free_consistent(bridge->parent, size, vaddr, dma);

  }
  EXPORT_SYMBOL(vme_free_consistent);

  /**
   * vme_get_size - Helper function returning size of a VME window
   * @resource: Pointer to VME slave or master resource.
   *
   * Determine the size of the VME window provided. This is a helper
   * function, wrappering the call to vme_master_get or vme_slave_get
   * depending on the type of window resource handed to it.
   *
   * Return: Size of the window on success, zero on failure.
   */

  size_t vme_get_size(struct vme_resource *resource)
  {
  	int enabled, retval;
  	unsigned long long base, size;
  	dma_addr_t buf_base;

  	u32 aspace, cycle, dwidth;

  
  	switch (resource->type) {
  	case VME_MASTER:
  		retval = vme_master_get(resource, &enabled, &base, &size,
  			&aspace, &cycle, &dwidth);

  		if (retval)
  			return 0;

  
  		return size;
  		break;
  	case VME_SLAVE:
  		retval = vme_slave_get(resource, &enabled, &base, &size,
  			&buf_base, &aspace, &cycle);

  		if (retval)
  			return 0;

  
  		return size;
  		break;
  	case VME_DMA:
  		return 0;
  		break;
  	default:
  		printk(KERN_ERR "Unknown resource type
  ");
  		return 0;
  		break;
  	}
  }
  EXPORT_SYMBOL(vme_get_size);

  int vme_check_window(u32 aspace, unsigned long long vme_base,
  		     unsigned long long size)

  {
  	int retval = 0;

  	if (vme_base + size < size)
  		return -EINVAL;

  	switch (aspace) {
  	case VME_A16:

  		if (vme_base + size > VME_A16_MAX)

  			retval = -EFAULT;
  		break;
  	case VME_A24:

  		if (vme_base + size > VME_A24_MAX)

  			retval = -EFAULT;
  		break;
  	case VME_A32:

  		if (vme_base + size > VME_A32_MAX)

  			retval = -EFAULT;
  		break;
  	case VME_A64:

  		/* The VME_A64_MAX limit is actually U64_MAX + 1 */

  		break;
  	case VME_CRCSR:

  		if (vme_base + size > VME_CRCSR_MAX)

  			retval = -EFAULT;
  		break;
  	case VME_USER1:
  	case VME_USER2:
  	case VME_USER3:
  	case VME_USER4:
  		/* User Defined */
  		break;
  	default:

  		printk(KERN_ERR "Invalid address space
  ");

  		retval = -EINVAL;
  		break;
  	}
  
  	return retval;
  }

  EXPORT_SYMBOL(vme_check_window);

  static u32 vme_get_aspace(int am)
  {
  	switch (am) {
  	case 0x29:
  	case 0x2D:
  		return VME_A16;
  	case 0x38:
  	case 0x39:
  	case 0x3A:
  	case 0x3B:
  	case 0x3C:
  	case 0x3D:
  	case 0x3E:
  	case 0x3F:
  		return VME_A24;
  	case 0x8:
  	case 0x9:
  	case 0xA:
  	case 0xB:
  	case 0xC:
  	case 0xD:
  	case 0xE:
  	case 0xF:
  		return VME_A32;
  	case 0x0:
  	case 0x1:
  	case 0x3:
  		return VME_A64;
  	}
  
  	return 0;
  }

  /**
   * vme_slave_request - Request a VME slave window resource.
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   * @address: Required VME address space.
   * @cycle: Required VME data transfer cycle type.
   *
   * Request use of a VME window resource capable of being set for the requested
   * address space and data transfer cycle.
   *
   * Return: Pointer to VME resource on success, NULL on failure.

   */

  struct vme_resource *vme_slave_request(struct vme_dev *vdev, u32 address,
  	u32 cycle)

  {
  	struct vme_bridge *bridge;
  	struct list_head *slave_pos = NULL;
  	struct vme_slave_resource *allocated_image = NULL;
  	struct vme_slave_resource *slave_image = NULL;
  	struct vme_resource *resource = NULL;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		goto err_bus;
  	}
  
  	/* Loop through slave resources */

  	list_for_each(slave_pos, &bridge->slave_resources) {

  		slave_image = list_entry(slave_pos,
  			struct vme_slave_resource, list);

  		if (!slave_image) {

  			printk(KERN_ERR "Registered NULL Slave resource
  ");

  			continue;
  		}
  
  		/* Find an unlocked and compatible image */

  		mutex_lock(&slave_image->mtx);

  		if (((slave_image->address_attr & address) == address) &&

  			((slave_image->cycle_attr & cycle) == cycle) &&
  			(slave_image->locked == 0)) {
  
  			slave_image->locked = 1;

  			mutex_unlock(&slave_image->mtx);

  			allocated_image = slave_image;
  			break;
  		}

  		mutex_unlock(&slave_image->mtx);

  	}
  
  	/* No free image */

  	if (!allocated_image)

  		goto err_image;

  	resource = kmalloc(sizeof(*resource), GFP_KERNEL);

  	if (!resource)

  		goto err_alloc;

  	resource->type = VME_SLAVE;

  	resource->entry = &allocated_image->list;

  
  	return resource;
  
  err_alloc:
  	/* Unlock image */

  	mutex_lock(&slave_image->mtx);

  	slave_image->locked = 0;

  	mutex_unlock(&slave_image->mtx);

  err_image:
  err_bus:
  	return NULL;
  }
  EXPORT_SYMBOL(vme_slave_request);

  /**
   * vme_slave_set - Set VME slave window configuration.
   * @resource: Pointer to VME slave resource.
   * @enabled: State to which the window should be configured.
   * @vme_base: Base address for the window.
   * @size: Size of the VME window.
   * @buf_base: Based address of buffer used to provide VME slave window storage.
   * @aspace: VME address space for the VME window.
   * @cycle: VME data transfer cycle type for the VME window.
   *
   * Set configuration for provided VME slave window.
   *
   * Return: Zero on success, -EINVAL if operation is not supported on this
   *         device, if an invalid resource has been provided or invalid
   *         attributes are provided. Hardware specific errors may also be
   *         returned.
   */

  int vme_slave_set(struct vme_resource *resource, int enabled,

  	unsigned long long vme_base, unsigned long long size,

  	dma_addr_t buf_base, u32 aspace, u32 cycle)

  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_slave_resource *image;
  	int retval;
  
  	if (resource->type != VME_SLAVE) {

  		printk(KERN_ERR "Not a slave resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_slave_resource, list);

  	if (!bridge->slave_set) {

  		printk(KERN_ERR "Function not supported
  ");

  		return -ENOSYS;
  	}

  	if (!(((image->address_attr & aspace) == aspace) &&

  		((image->cycle_attr & cycle) == cycle))) {

  		printk(KERN_ERR "Invalid attributes
  ");

  		return -EINVAL;
  	}
  
  	retval = vme_check_window(aspace, vme_base, size);

  	if (retval)

  		return retval;
  
  	return bridge->slave_set(image, enabled, vme_base, size, buf_base,
  		aspace, cycle);
  }
  EXPORT_SYMBOL(vme_slave_set);

  /**
   * vme_slave_get - Retrieve VME slave window configuration.
   * @resource: Pointer to VME slave resource.
   * @enabled: Pointer to variable for storing state.
   * @vme_base: Pointer to variable for storing window base address.
   * @size: Pointer to variable for storing window size.
   * @buf_base: Pointer to variable for storing slave buffer base address.
   * @aspace: Pointer to variable for storing VME address space.
   * @cycle: Pointer to variable for storing VME data transfer cycle type.
   *
   * Return configuration for provided VME slave window.
   *
   * Return: Zero on success, -EINVAL if operation is not supported on this
   *         device or if an invalid resource has been provided.
   */

  int vme_slave_get(struct vme_resource *resource, int *enabled,

  	unsigned long long *vme_base, unsigned long long *size,

  	dma_addr_t *buf_base, u32 *aspace, u32 *cycle)

  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_slave_resource *image;
  
  	if (resource->type != VME_SLAVE) {

  		printk(KERN_ERR "Not a slave resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_slave_resource, list);

  	if (!bridge->slave_get) {

  		printk(KERN_ERR "vme_slave_get not supported
  ");

  		return -EINVAL;
  	}
  
  	return bridge->slave_get(image, enabled, vme_base, size, buf_base,
  		aspace, cycle);
  }
  EXPORT_SYMBOL(vme_slave_get);

  /**
   * vme_slave_free - Free VME slave window
   * @resource: Pointer to VME slave resource.
   *
   * Free the provided slave resource so that it may be reallocated.
   */

  void vme_slave_free(struct vme_resource *resource)
  {
  	struct vme_slave_resource *slave_image;
  
  	if (resource->type != VME_SLAVE) {

  		printk(KERN_ERR "Not a slave resource
  ");

  		return;
  	}
  
  	slave_image = list_entry(resource->entry, struct vme_slave_resource,
  		list);

  	if (!slave_image) {

  		printk(KERN_ERR "Can't find slave resource
  ");

  		return;
  	}
  
  	/* Unlock image */

  	mutex_lock(&slave_image->mtx);

  	if (slave_image->locked == 0)
  		printk(KERN_ERR "Image is already free
  ");
  
  	slave_image->locked = 0;

  	mutex_unlock(&slave_image->mtx);

  
  	/* Free up resource memory */
  	kfree(resource);
  }
  EXPORT_SYMBOL(vme_slave_free);

  /**
   * vme_master_request - Request a VME master window resource.
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   * @address: Required VME address space.
   * @cycle: Required VME data transfer cycle type.
   * @dwidth: Required VME data transfer width.
   *
   * Request use of a VME window resource capable of being set for the requested
   * address space, data transfer cycle and width.
   *
   * Return: Pointer to VME resource on success, NULL on failure.

   */

  struct vme_resource *vme_master_request(struct vme_dev *vdev, u32 address,
  	u32 cycle, u32 dwidth)

  {
  	struct vme_bridge *bridge;
  	struct list_head *master_pos = NULL;
  	struct vme_master_resource *allocated_image = NULL;
  	struct vme_master_resource *master_image = NULL;
  	struct vme_resource *resource = NULL;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		goto err_bus;
  	}
  
  	/* Loop through master resources */

  	list_for_each(master_pos, &bridge->master_resources) {

  		master_image = list_entry(master_pos,
  			struct vme_master_resource, list);

  		if (!master_image) {

  			printk(KERN_WARNING "Registered NULL master resource
  ");
  			continue;
  		}
  
  		/* Find an unlocked and compatible image */

  		spin_lock(&master_image->lock);

  		if (((master_image->address_attr & address) == address) &&

  			((master_image->cycle_attr & cycle) == cycle) &&
  			((master_image->width_attr & dwidth) == dwidth) &&
  			(master_image->locked == 0)) {
  
  			master_image->locked = 1;

  			spin_unlock(&master_image->lock);

  			allocated_image = master_image;
  			break;
  		}

  		spin_unlock(&master_image->lock);

  	}
  
  	/* Check to see if we found a resource */

  	if (!allocated_image) {

  		printk(KERN_ERR "Can't find a suitable resource
  ");
  		goto err_image;
  	}

  	resource = kmalloc(sizeof(*resource), GFP_KERNEL);

  	if (!resource)

  		goto err_alloc;

  	resource->type = VME_MASTER;

  	resource->entry = &allocated_image->list;

  
  	return resource;

  err_alloc:
  	/* Unlock image */

  	spin_lock(&master_image->lock);

  	master_image->locked = 0;

  	spin_unlock(&master_image->lock);

  err_image:
  err_bus:
  	return NULL;
  }
  EXPORT_SYMBOL(vme_master_request);

  /**
   * vme_master_set - Set VME master window configuration.
   * @resource: Pointer to VME master resource.
   * @enabled: State to which the window should be configured.
   * @vme_base: Base address for the window.
   * @size: Size of the VME window.
   * @aspace: VME address space for the VME window.
   * @cycle: VME data transfer cycle type for the VME window.
   * @dwidth: VME data transfer width for the VME window.
   *
   * Set configuration for provided VME master window.
   *
   * Return: Zero on success, -EINVAL if operation is not supported on this
   *         device, if an invalid resource has been provided or invalid
   *         attributes are provided. Hardware specific errors may also be
   *         returned.
   */

  int vme_master_set(struct vme_resource *resource, int enabled,

  	unsigned long long vme_base, unsigned long long size, u32 aspace,
  	u32 cycle, u32 dwidth)

  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_master_resource *image;
  	int retval;
  
  	if (resource->type != VME_MASTER) {

  		printk(KERN_ERR "Not a master resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_master_resource, list);

  	if (!bridge->master_set) {

  		printk(KERN_WARNING "vme_master_set not supported
  ");

  		return -EINVAL;
  	}

  	if (!(((image->address_attr & aspace) == aspace) &&

  		((image->cycle_attr & cycle) == cycle) &&
  		((image->width_attr & dwidth) == dwidth))) {

  		printk(KERN_WARNING "Invalid attributes
  ");

  		return -EINVAL;
  	}
  
  	retval = vme_check_window(aspace, vme_base, size);

  	if (retval)

  		return retval;
  
  	return bridge->master_set(image, enabled, vme_base, size, aspace,
  		cycle, dwidth);
  }
  EXPORT_SYMBOL(vme_master_set);

  /**
   * vme_master_get - Retrieve VME master window configuration.
   * @resource: Pointer to VME master resource.
   * @enabled: Pointer to variable for storing state.
   * @vme_base: Pointer to variable for storing window base address.
   * @size: Pointer to variable for storing window size.
   * @aspace: Pointer to variable for storing VME address space.
   * @cycle: Pointer to variable for storing VME data transfer cycle type.
   * @dwidth: Pointer to variable for storing VME data transfer width.
   *
   * Return configuration for provided VME master window.
   *
   * Return: Zero on success, -EINVAL if operation is not supported on this
   *         device or if an invalid resource has been provided.
   */

  int vme_master_get(struct vme_resource *resource, int *enabled,

  	unsigned long long *vme_base, unsigned long long *size, u32 *aspace,
  	u32 *cycle, u32 *dwidth)

  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_master_resource *image;
  
  	if (resource->type != VME_MASTER) {

  		printk(KERN_ERR "Not a master resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_master_resource, list);

  	if (!bridge->master_get) {

  		printk(KERN_WARNING "%s not supported
  ", __func__);

  		return -EINVAL;
  	}
  
  	return bridge->master_get(image, enabled, vme_base, size, aspace,
  		cycle, dwidth);
  }
  EXPORT_SYMBOL(vme_master_get);

  /**
   * vme_master_write - Read data from VME space into a buffer.
   * @resource: Pointer to VME master resource.
   * @buf: Pointer to buffer where data should be transferred.
   * @count: Number of bytes to transfer.
   * @offset: Offset into VME master window at which to start transfer.
   *
   * Perform read of count bytes of data from location on VME bus which maps into
   * the VME master window at offset to buf.
   *
   * Return: Number of bytes read, -EINVAL if resource is not a VME master
   *         resource or read operation is not supported. -EFAULT returned if
   *         invalid offset is provided. Hardware specific errors may also be
   *         returned.

   */

  ssize_t vme_master_read(struct vme_resource *resource, void *buf, size_t count,

  	loff_t offset)
  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_master_resource *image;
  	size_t length;

  	if (!bridge->master_read) {

  		printk(KERN_WARNING "Reading from resource not supported
  ");

  		return -EINVAL;
  	}
  
  	if (resource->type != VME_MASTER) {

  		printk(KERN_ERR "Not a master resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_master_resource, list);
  
  	length = vme_get_size(resource);
  
  	if (offset > length) {

  		printk(KERN_WARNING "Invalid Offset
  ");

  		return -EFAULT;
  	}
  
  	if ((offset + count) > length)
  		count = length - offset;
  
  	return bridge->master_read(image, buf, count, offset);
  
  }
  EXPORT_SYMBOL(vme_master_read);

  /**
   * vme_master_write - Write data out to VME space from a buffer.
   * @resource: Pointer to VME master resource.
   * @buf: Pointer to buffer holding data to transfer.
   * @count: Number of bytes to transfer.
   * @offset: Offset into VME master window at which to start transfer.
   *
   * Perform write of count bytes of data from buf to location on VME bus which
   * maps into the VME master window at offset.
   *
   * Return: Number of bytes written, -EINVAL if resource is not a VME master
   *         resource or write operation is not supported. -EFAULT returned if
   *         invalid offset is provided. Hardware specific errors may also be
   *         returned.

   */

  ssize_t vme_master_write(struct vme_resource *resource, void *buf,

  	size_t count, loff_t offset)
  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_master_resource *image;
  	size_t length;

  	if (!bridge->master_write) {

  		printk(KERN_WARNING "Writing to resource not supported
  ");

  		return -EINVAL;
  	}
  
  	if (resource->type != VME_MASTER) {

  		printk(KERN_ERR "Not a master resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_master_resource, list);
  
  	length = vme_get_size(resource);
  
  	if (offset > length) {

  		printk(KERN_WARNING "Invalid Offset
  ");

  		return -EFAULT;
  	}
  
  	if ((offset + count) > length)
  		count = length - offset;
  
  	return bridge->master_write(image, buf, count, offset);
  }
  EXPORT_SYMBOL(vme_master_write);

  /**
   * vme_master_rmw - Perform read-modify-write cycle.
   * @resource: Pointer to VME master resource.
   * @mask: Bits to be compared and swapped in operation.
   * @compare: Bits to be compared with data read from offset.
   * @swap: Bits to be swapped in data read from offset.
   * @offset: Offset into VME master window at which to perform operation.
   *
   * Perform read-modify-write cycle on provided location:
   * - Location on VME bus is read.
   * - Bits selected by mask are compared with compare.
   * - Where a selected bit matches that in compare and are selected in swap,
   * the bit is swapped.
   * - Result written back to location on VME bus.
   *
   * Return: Bytes written on success, -EINVAL if resource is not a VME master
   *         resource or RMW operation is not supported. Hardware specific
   *         errors may also be returned.

   */

  unsigned int vme_master_rmw(struct vme_resource *resource, unsigned int mask,

  	unsigned int compare, unsigned int swap, loff_t offset)
  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_master_resource *image;

  	if (!bridge->master_rmw) {

  		printk(KERN_WARNING "Writing to resource not supported
  ");

  		return -EINVAL;
  	}
  
  	if (resource->type != VME_MASTER) {

  		printk(KERN_ERR "Not a master resource
  ");

  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_master_resource, list);
  
  	return bridge->master_rmw(image, mask, compare, swap, offset);
  }
  EXPORT_SYMBOL(vme_master_rmw);

  /**
   * vme_master_mmap - Mmap region of VME master window.
   * @resource: Pointer to VME master resource.
   * @vma: Pointer to definition of user mapping.
   *
   * Memory map a region of the VME master window into user space.
   *
   * Return: Zero on success, -EINVAL if resource is not a VME master
   *         resource or -EFAULT if map exceeds window size. Other generic mmap
   *         errors may also be returned.
   */

  int vme_master_mmap(struct vme_resource *resource, struct vm_area_struct *vma)
  {
  	struct vme_master_resource *image;
  	phys_addr_t phys_addr;
  	unsigned long vma_size;
  
  	if (resource->type != VME_MASTER) {
  		pr_err("Not a master resource
  ");
  		return -EINVAL;
  	}
  
  	image = list_entry(resource->entry, struct vme_master_resource, list);
  	phys_addr = image->bus_resource.start + (vma->vm_pgoff << PAGE_SHIFT);
  	vma_size = vma->vm_end - vma->vm_start;
  
  	if (phys_addr + vma_size > image->bus_resource.end + 1) {
  		pr_err("Map size cannot exceed the window size
  ");
  		return -EFAULT;
  	}
  
  	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
  
  	return vm_iomap_memory(vma, phys_addr, vma->vm_end - vma->vm_start);
  }
  EXPORT_SYMBOL(vme_master_mmap);

  /**
   * vme_master_free - Free VME master window
   * @resource: Pointer to VME master resource.
   *
   * Free the provided master resource so that it may be reallocated.
   */

  void vme_master_free(struct vme_resource *resource)
  {
  	struct vme_master_resource *master_image;
  
  	if (resource->type != VME_MASTER) {

  		printk(KERN_ERR "Not a master resource
  ");

  		return;
  	}
  
  	master_image = list_entry(resource->entry, struct vme_master_resource,
  		list);

  	if (!master_image) {

  		printk(KERN_ERR "Can't find master resource
  ");

  		return;
  	}
  
  	/* Unlock image */

  	spin_lock(&master_image->lock);

  	if (master_image->locked == 0)
  		printk(KERN_ERR "Image is already free
  ");
  
  	master_image->locked = 0;

  	spin_unlock(&master_image->lock);

  
  	/* Free up resource memory */
  	kfree(resource);
  }
  EXPORT_SYMBOL(vme_master_free);

  /**
   * vme_dma_request - Request a DMA controller.
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   * @route: Required src/destination combination.
   *
   * Request a VME DMA controller with capability to perform transfers bewteen
   * requested source/destination combination.
   *
   * Return: Pointer to VME DMA resource on success, NULL on failure.

   */

  struct vme_resource *vme_dma_request(struct vme_dev *vdev, u32 route)

  {
  	struct vme_bridge *bridge;
  	struct list_head *dma_pos = NULL;
  	struct vme_dma_resource *allocated_ctrlr = NULL;
  	struct vme_dma_resource *dma_ctrlr = NULL;
  	struct vme_resource *resource = NULL;
  
  	/* XXX Not checking resource attributes */
  	printk(KERN_ERR "No VME resource Attribute tests done
  ");

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		goto err_bus;
  	}
  
  	/* Loop through DMA resources */

  	list_for_each(dma_pos, &bridge->dma_resources) {

  		dma_ctrlr = list_entry(dma_pos,
  			struct vme_dma_resource, list);

  		if (!dma_ctrlr) {

  			printk(KERN_ERR "Registered NULL DMA resource
  ");

  			continue;
  		}

  		/* Find an unlocked and compatible controller */

  		mutex_lock(&dma_ctrlr->mtx);

  		if (((dma_ctrlr->route_attr & route) == route) &&
  			(dma_ctrlr->locked == 0)) {

  			dma_ctrlr->locked = 1;

  			mutex_unlock(&dma_ctrlr->mtx);

  			allocated_ctrlr = dma_ctrlr;
  			break;
  		}

  		mutex_unlock(&dma_ctrlr->mtx);

  	}
  
  	/* Check to see if we found a resource */

  	if (!allocated_ctrlr)

  		goto err_ctrlr;

  	resource = kmalloc(sizeof(*resource), GFP_KERNEL);

  	if (!resource)

  		goto err_alloc;

  	resource->type = VME_DMA;

  	resource->entry = &allocated_ctrlr->list;

  
  	return resource;
  
  err_alloc:
  	/* Unlock image */

  	mutex_lock(&dma_ctrlr->mtx);

  	dma_ctrlr->locked = 0;

  	mutex_unlock(&dma_ctrlr->mtx);

  err_ctrlr:
  err_bus:
  	return NULL;
  }

  EXPORT_SYMBOL(vme_dma_request);

  /**
   * vme_new_dma_list - Create new VME DMA list.
   * @resource: Pointer to VME DMA resource.
   *
   * Create a new VME DMA list. It is the responsibility of the user to free
   * the list once it is no longer required with vme_dma_list_free().
   *
   * Return: Pointer to new VME DMA list, NULL on allocation failure or invalid
   *         VME DMA resource.

   */
  struct vme_dma_list *vme_new_dma_list(struct vme_resource *resource)
  {

  	struct vme_dma_list *dma_list;
  
  	if (resource->type != VME_DMA) {

  		printk(KERN_ERR "Not a DMA resource
  ");

  		return NULL;
  	}

  	dma_list = kmalloc(sizeof(*dma_list), GFP_KERNEL);

  	if (!dma_list)

  		return NULL;

  	INIT_LIST_HEAD(&dma_list->entries);

  	dma_list->parent = list_entry(resource->entry,
  				      struct vme_dma_resource,
  				      list);

  	mutex_init(&dma_list->mtx);

  
  	return dma_list;
  }
  EXPORT_SYMBOL(vme_new_dma_list);

  /**
   * vme_dma_pattern_attribute - Create "Pattern" type VME DMA list attribute.
   * @pattern: Value to use used as pattern
   * @type: Type of pattern to be written.
   *
   * Create VME DMA list attribute for pattern generation. It is the
   * responsibility of the user to free used attributes using
   * vme_dma_free_attribute().
   *
   * Return: Pointer to VME DMA attribute, NULL on failure.

   */

  struct vme_dma_attr *vme_dma_pattern_attribute(u32 pattern, u32 type)

  {
  	struct vme_dma_attr *attributes;
  	struct vme_dma_pattern *pattern_attr;

  	attributes = kmalloc(sizeof(*attributes), GFP_KERNEL);

  	if (!attributes)

  		goto err_attr;

  	pattern_attr = kmalloc(sizeof(*pattern_attr), GFP_KERNEL);

  	if (!pattern_attr)

  		goto err_pat;

  
  	attributes->type = VME_DMA_PATTERN;
  	attributes->private = (void *)pattern_attr;
  
  	pattern_attr->pattern = pattern;
  	pattern_attr->type = type;
  
  	return attributes;

  err_pat:
  	kfree(attributes);
  err_attr:
  	return NULL;
  }
  EXPORT_SYMBOL(vme_dma_pattern_attribute);

  /**
   * vme_dma_pci_attribute - Create "PCI" type VME DMA list attribute.
   * @address: PCI base address for DMA transfer.
   *
   * Create VME DMA list attribute pointing to a location on PCI for DMA
   * transfers. It is the responsibility of the user to free used attributes
   * using vme_dma_free_attribute().
   *
   * Return: Pointer to VME DMA attribute, NULL on failure.

   */
  struct vme_dma_attr *vme_dma_pci_attribute(dma_addr_t address)
  {
  	struct vme_dma_attr *attributes;
  	struct vme_dma_pci *pci_attr;
  
  	/* XXX Run some sanity checks here */

  	attributes = kmalloc(sizeof(*attributes), GFP_KERNEL);

  	if (!attributes)

  		goto err_attr;

  	pci_attr = kmalloc(sizeof(*pci_attr), GFP_KERNEL);

  	if (!pci_attr)

  		goto err_pci;

  
  	attributes->type = VME_DMA_PCI;
  	attributes->private = (void *)pci_attr;
  
  	pci_attr->address = address;
  
  	return attributes;

  err_pci:
  	kfree(attributes);
  err_attr:
  	return NULL;
  }
  EXPORT_SYMBOL(vme_dma_pci_attribute);

  /**
   * vme_dma_vme_attribute - Create "VME" type VME DMA list attribute.
   * @address: VME base address for DMA transfer.
   * @aspace: VME address space to use for DMA transfer.
   * @cycle: VME bus cycle to use for DMA transfer.
   * @dwidth: VME data width to use for DMA transfer.
   *
   * Create VME DMA list attribute pointing to a location on the VME bus for DMA
   * transfers. It is the responsibility of the user to free used attributes
   * using vme_dma_free_attribute().
   *
   * Return: Pointer to VME DMA attribute, NULL on failure.

   */
  struct vme_dma_attr *vme_dma_vme_attribute(unsigned long long address,

  	u32 aspace, u32 cycle, u32 dwidth)

  {
  	struct vme_dma_attr *attributes;
  	struct vme_dma_vme *vme_attr;

  	attributes = kmalloc(sizeof(*attributes), GFP_KERNEL);

  	if (!attributes)

  		goto err_attr;

  	vme_attr = kmalloc(sizeof(*vme_attr), GFP_KERNEL);

  	if (!vme_attr)

  		goto err_vme;

  
  	attributes->type = VME_DMA_VME;
  	attributes->private = (void *)vme_attr;
  
  	vme_attr->address = address;
  	vme_attr->aspace = aspace;
  	vme_attr->cycle = cycle;
  	vme_attr->dwidth = dwidth;
  
  	return attributes;

  err_vme:
  	kfree(attributes);
  err_attr:
  	return NULL;
  }
  EXPORT_SYMBOL(vme_dma_vme_attribute);

  /**
   * vme_dma_free_attribute - Free DMA list attribute.
   * @attributes: Pointer to DMA list attribute.
   *
   * Free VME DMA list attribute. VME DMA list attributes can be safely freed
   * once vme_dma_list_add() has returned.

   */
  void vme_dma_free_attribute(struct vme_dma_attr *attributes)
  {
  	kfree(attributes->private);
  	kfree(attributes);
  }
  EXPORT_SYMBOL(vme_dma_free_attribute);

  /**
   * vme_dma_list_add - Add enty to a VME DMA list.
   * @list: Pointer to VME list.
   * @src: Pointer to DMA list attribute to use as source.
   * @dest: Pointer to DMA list attribute to use as destination.
   * @count: Number of bytes to transfer.
   *
   * Add an entry to the provided VME DMA list. Entry requires pointers to source
   * and destination DMA attributes and a count.
   *
   * Please note, the attributes supported as source and destinations for
   * transfers are hardware dependent.
   *
   * Return: Zero on success, -EINVAL if operation is not supported on this
   *         device or if the link list has already been submitted for execution.
   *         Hardware specific errors also possible.
   */

  int vme_dma_list_add(struct vme_dma_list *list, struct vme_dma_attr *src,
  	struct vme_dma_attr *dest, size_t count)
  {
  	struct vme_bridge *bridge = list->parent->parent;
  	int retval;

  	if (!bridge->dma_list_add) {

  		printk(KERN_WARNING "Link List DMA generation not supported
  ");

  		return -EINVAL;
  	}

  	if (!mutex_trylock(&list->mtx)) {

  		printk(KERN_ERR "Link List already submitted
  ");

  		return -EINVAL;
  	}
  
  	retval = bridge->dma_list_add(list, src, dest, count);

  	mutex_unlock(&list->mtx);

  
  	return retval;
  }
  EXPORT_SYMBOL(vme_dma_list_add);

  /**
   * vme_dma_list_exec - Queue a VME DMA list for execution.
   * @list: Pointer to VME list.
   *
   * Queue the provided VME DMA list for execution. The call will return once the
   * list has been executed.
   *
   * Return: Zero on success, -EINVAL if operation is not supported on this
   *         device. Hardware specific errors also possible.
   */

  int vme_dma_list_exec(struct vme_dma_list *list)
  {
  	struct vme_bridge *bridge = list->parent->parent;
  	int retval;

  	if (!bridge->dma_list_exec) {

  		printk(KERN_ERR "Link List DMA execution not supported
  ");

  		return -EINVAL;
  	}

  	mutex_lock(&list->mtx);

  
  	retval = bridge->dma_list_exec(list);

  	mutex_unlock(&list->mtx);

  
  	return retval;
  }
  EXPORT_SYMBOL(vme_dma_list_exec);

  /**
   * vme_dma_list_free - Free a VME DMA list.
   * @list: Pointer to VME list.
   *
   * Free the provided DMA list and all its entries.
   *
   * Return: Zero on success, -EINVAL on invalid VME resource, -EBUSY if resource
   *         is still in use. Hardware specific errors also possible.
   */

  int vme_dma_list_free(struct vme_dma_list *list)
  {
  	struct vme_bridge *bridge = list->parent->parent;
  	int retval;

  	if (!bridge->dma_list_empty) {

  		printk(KERN_WARNING "Emptying of Link Lists not supported
  ");

  		return -EINVAL;
  	}

  	if (!mutex_trylock(&list->mtx)) {

  		printk(KERN_ERR "Link List in use
  ");

  		return -EBUSY;

  	}
  
  	/*

  	 * Empty out all of the entries from the DMA list. We need to go to the
  	 * low level driver as DMA entries are driver specific.

  	 */
  	retval = bridge->dma_list_empty(list);
  	if (retval) {

  		printk(KERN_ERR "Unable to empty link-list entries
  ");

  		mutex_unlock(&list->mtx);

  		return retval;
  	}

  	mutex_unlock(&list->mtx);

  	kfree(list);
  
  	return retval;
  }
  EXPORT_SYMBOL(vme_dma_list_free);

  /**
   * vme_dma_free - Free a VME DMA resource.
   * @resource: Pointer to VME DMA resource.
   *
   * Free the provided DMA resource so that it may be reallocated.
   *
   * Return: Zero on success, -EINVAL on invalid VME resource, -EBUSY if resource
   *         is still active.
   */

  int vme_dma_free(struct vme_resource *resource)
  {
  	struct vme_dma_resource *ctrlr;
  
  	if (resource->type != VME_DMA) {

  		printk(KERN_ERR "Not a DMA resource
  ");

  		return -EINVAL;
  	}
  
  	ctrlr = list_entry(resource->entry, struct vme_dma_resource, list);

  	if (!mutex_trylock(&ctrlr->mtx)) {

  		printk(KERN_ERR "Resource busy, can't free
  ");

  		return -EBUSY;
  	}

  	if (!(list_empty(&ctrlr->pending) && list_empty(&ctrlr->running))) {

  		printk(KERN_WARNING "Resource still processing transfers
  ");

  		mutex_unlock(&ctrlr->mtx);

  		return -EBUSY;
  	}
  
  	ctrlr->locked = 0;

  	mutex_unlock(&ctrlr->mtx);

  	kfree(resource);

  	return 0;
  }
  EXPORT_SYMBOL(vme_dma_free);

  void vme_bus_error_handler(struct vme_bridge *bridge,

  			   unsigned long long address, int am)

  {

  	struct list_head *handler_pos = NULL;
  	struct vme_error_handler *handler;

  	int handler_triggered = 0;

  	u32 aspace = vme_get_aspace(am);
  
  	list_for_each(handler_pos, &bridge->vme_error_handlers) {
  		handler = list_entry(handler_pos, struct vme_error_handler,
  				     list);
  		if ((aspace == handler->aspace) &&
  		    (address >= handler->start) &&
  		    (address < handler->end)) {
  			if (!handler->num_errors)
  				handler->first_error = address;
  			if (handler->num_errors != UINT_MAX)
  				handler->num_errors++;

  			handler_triggered = 1;

  		}

  	}

  
  	if (!handler_triggered)
  		dev_err(bridge->parent,
  			"Unhandled VME access error at address 0x%llx
  ",
  			address);

  }
  EXPORT_SYMBOL(vme_bus_error_handler);

  struct vme_error_handler *vme_register_error_handler(
  	struct vme_bridge *bridge, u32 aspace,
  	unsigned long long address, size_t len)

  {

  	struct vme_error_handler *handler;

  	handler = kmalloc(sizeof(*handler), GFP_ATOMIC);

  	if (!handler)
  		return NULL;

  	handler->aspace = aspace;
  	handler->start = address;
  	handler->end = address + len;
  	handler->num_errors = 0;
  	handler->first_error = 0;
  	list_add_tail(&handler->list, &bridge->vme_error_handlers);

  	return handler;

  }

  EXPORT_SYMBOL(vme_register_error_handler);

  void vme_unregister_error_handler(struct vme_error_handler *handler)

  {

  	list_del(&handler->list);
  	kfree(handler);

  }

  EXPORT_SYMBOL(vme_unregister_error_handler);

  void vme_irq_handler(struct vme_bridge *bridge, int level, int statid)
  {
  	void (*call)(int, int, void *);
  	void *priv_data;
  
  	call = bridge->irq[level - 1].callback[statid].func;
  	priv_data = bridge->irq[level - 1].callback[statid].priv_data;

  	if (call)

  		call(level, statid, priv_data);
  	else

  		printk(KERN_WARNING "Spurious VME interrupt, level:%x, vector:%x
  ",

  		       level, statid);

  }
  EXPORT_SYMBOL(vme_irq_handler);

  /**
   * vme_irq_request - Request a specific VME interrupt.
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   * @level: Interrupt priority being requested.
   * @statid: Interrupt vector being requested.
   * @callback: Pointer to callback function called when VME interrupt/vector
   *            received.
   * @priv_data: Generic pointer that will be passed to the callback function.
   *
   * Request callback to be attached as a handler for VME interrupts with provided
   * level and statid.
   *
   * Return: Zero on success, -EINVAL on invalid vme device, level or if the
   *         function is not supported, -EBUSY if the level/statid combination is
   *         already in use. Hardware specific errors also possible.
   */

  int vme_irq_request(struct vme_dev *vdev, int level, int statid,

  	void (*callback)(int, int, void *),

  	void *priv_data)
  {
  	struct vme_bridge *bridge;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		return -EINVAL;
  	}

  	if ((level < 1) || (level > 7)) {

  		printk(KERN_ERR "Invalid interrupt level
  ");

  		return -EINVAL;
  	}

  	if (!bridge->irq_set) {

  		printk(KERN_ERR "Configuring interrupts not supported
  ");

  		return -EINVAL;
  	}

  	mutex_lock(&bridge->irq_mtx);

  
  	if (bridge->irq[level - 1].callback[statid].func) {

  		mutex_unlock(&bridge->irq_mtx);

  		printk(KERN_WARNING "VME Interrupt already taken
  ");
  		return -EBUSY;
  	}
  
  	bridge->irq[level - 1].count++;
  	bridge->irq[level - 1].callback[statid].priv_data = priv_data;
  	bridge->irq[level - 1].callback[statid].func = callback;
  
  	/* Enable IRQ level */

  	bridge->irq_set(bridge, level, 1, 1);

  	mutex_unlock(&bridge->irq_mtx);

  
  	return 0;

  }

  EXPORT_SYMBOL(vme_irq_request);

  /**
   * vme_irq_free - Free a VME interrupt.
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   * @level: Interrupt priority of interrupt being freed.
   * @statid: Interrupt vector of interrupt being freed.
   *
   * Remove previously attached callback from VME interrupt priority/vector.
   */

  void vme_irq_free(struct vme_dev *vdev, int level, int statid)

  {
  	struct vme_bridge *bridge;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		return;
  	}

  	if ((level < 1) || (level > 7)) {

  		printk(KERN_ERR "Invalid interrupt level
  ");

  		return;
  	}

  	if (!bridge->irq_set) {

  		printk(KERN_ERR "Configuring interrupts not supported
  ");

  		return;
  	}

  	mutex_lock(&bridge->irq_mtx);

  
  	bridge->irq[level - 1].count--;
  
  	/* Disable IRQ level if no more interrupts attached at this level*/
  	if (bridge->irq[level - 1].count == 0)

  		bridge->irq_set(bridge, level, 0, 1);

  
  	bridge->irq[level - 1].callback[statid].func = NULL;
  	bridge->irq[level - 1].callback[statid].priv_data = NULL;

  	mutex_unlock(&bridge->irq_mtx);

  }

  EXPORT_SYMBOL(vme_irq_free);

  /**
   * vme_irq_generate - Generate VME interrupt.
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   * @level: Interrupt priority at which to assert the interrupt.
   * @statid: Interrupt vector to associate with the interrupt.
   *
   * Generate a VME interrupt of the provided level and with the provided
   * statid.
   *
   * Return: Zero on success, -EINVAL on invalid vme device, level or if the
   *         function is not supported. Hardware specific errors also possible.
   */

  int vme_irq_generate(struct vme_dev *vdev, int level, int statid)

  {
  	struct vme_bridge *bridge;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		return -EINVAL;
  	}

  	if ((level < 1) || (level > 7)) {

  		printk(KERN_WARNING "Invalid interrupt level
  ");
  		return -EINVAL;
  	}

  	if (!bridge->irq_generate) {

  		printk(KERN_WARNING "Interrupt generation not supported
  ");

  		return -EINVAL;
  	}

  	return bridge->irq_generate(bridge, level, statid);

  }

  EXPORT_SYMBOL(vme_irq_generate);

  /**
   * vme_lm_request - Request a VME location monitor
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   *
   * Allocate a location monitor resource to the driver. A location monitor
   * allows the driver to monitor accesses to a contiguous number of
   * addresses on the VME bus.
   *
   * Return: Pointer to a VME resource on success or NULL on failure.

   */

  struct vme_resource *vme_lm_request(struct vme_dev *vdev)

  {
  	struct vme_bridge *bridge;

  	struct list_head *lm_pos = NULL;
  	struct vme_lm_resource *allocated_lm = NULL;
  	struct vme_lm_resource *lm = NULL;
  	struct vme_resource *resource = NULL;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");

  		goto err_bus;
  	}

  	/* Loop through LM resources */

  	list_for_each(lm_pos, &bridge->lm_resources) {

  		lm = list_entry(lm_pos,
  			struct vme_lm_resource, list);

  		if (!lm) {

  			printk(KERN_ERR "Registered NULL Location Monitor resource
  ");

  			continue;
  		}
  
  		/* Find an unlocked controller */

  		mutex_lock(&lm->mtx);

  		if (lm->locked == 0) {
  			lm->locked = 1;

  			mutex_unlock(&lm->mtx);

  			allocated_lm = lm;
  			break;
  		}

  		mutex_unlock(&lm->mtx);

  	}
  
  	/* Check to see if we found a resource */

  	if (!allocated_lm)

  		goto err_lm;

  	resource = kmalloc(sizeof(*resource), GFP_KERNEL);

  	if (!resource)

  		goto err_alloc;

  	resource->type = VME_LM;

  	resource->entry = &allocated_lm->list;

  
  	return resource;
  
  err_alloc:
  	/* Unlock image */

  	mutex_lock(&lm->mtx);

  	lm->locked = 0;

  	mutex_unlock(&lm->mtx);

  err_lm:
  err_bus:
  	return NULL;
  }
  EXPORT_SYMBOL(vme_lm_request);

  /**
   * vme_lm_count - Determine number of VME Addresses monitored
   * @resource: Pointer to VME location monitor resource.
   *
   * The number of contiguous addresses monitored is hardware dependent.
   * Return the number of contiguous addresses monitored by the
   * location monitor.
   *
   * Return: Count of addresses monitored or -EINVAL when provided with an
   *	   invalid location monitor resource.
   */

  int vme_lm_count(struct vme_resource *resource)
  {
  	struct vme_lm_resource *lm;
  
  	if (resource->type != VME_LM) {
  		printk(KERN_ERR "Not a Location Monitor resource
  ");
  		return -EINVAL;
  	}
  
  	lm = list_entry(resource->entry, struct vme_lm_resource, list);
  
  	return lm->monitors;
  }
  EXPORT_SYMBOL(vme_lm_count);

  /**
   * vme_lm_set - Configure location monitor
   * @resource: Pointer to VME location monitor resource.
   * @lm_base: Base address to monitor.
   * @aspace: VME address space to monitor.
   * @cycle: VME bus cycle type to monitor.
   *
   * Set the base address, address space and cycle type of accesses to be
   * monitored by the location monitor.
   *
   * Return: Zero on success, -EINVAL when provided with an invalid location
   *	   monitor resource or function is not supported. Hardware specific
   *	   errors may also be returned.
   */

  int vme_lm_set(struct vme_resource *resource, unsigned long long lm_base,

  	u32 aspace, u32 cycle)

  {
  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_lm_resource *lm;
  
  	if (resource->type != VME_LM) {
  		printk(KERN_ERR "Not a Location Monitor resource
  ");

  		return -EINVAL;
  	}

  	lm = list_entry(resource->entry, struct vme_lm_resource, list);

  	if (!bridge->lm_set) {

  		printk(KERN_ERR "vme_lm_set not supported
  ");

  		return -EINVAL;
  	}

  	return bridge->lm_set(lm, lm_base, aspace, cycle);

  }
  EXPORT_SYMBOL(vme_lm_set);

  /**
   * vme_lm_get - Retrieve location monitor settings
   * @resource: Pointer to VME location monitor resource.
   * @lm_base: Pointer used to output the base address monitored.
   * @aspace: Pointer used to output the address space monitored.
   * @cycle: Pointer used to output the VME bus cycle type monitored.
   *
   * Retrieve the base address, address space and cycle type of accesses to
   * be monitored by the location monitor.
   *
   * Return: Zero on success, -EINVAL when provided with an invalid location
   *	   monitor resource or function is not supported. Hardware specific
   *	   errors may also be returned.
   */

  int vme_lm_get(struct vme_resource *resource, unsigned long long *lm_base,

  	u32 *aspace, u32 *cycle)

  {

  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_lm_resource *lm;

  	if (resource->type != VME_LM) {
  		printk(KERN_ERR "Not a Location Monitor resource
  ");

  		return -EINVAL;
  	}

  	lm = list_entry(resource->entry, struct vme_lm_resource, list);

  	if (!bridge->lm_get) {

  		printk(KERN_ERR "vme_lm_get not supported
  ");

  		return -EINVAL;
  	}

  	return bridge->lm_get(lm, lm_base, aspace, cycle);

  }
  EXPORT_SYMBOL(vme_lm_get);

  /**
   * vme_lm_attach - Provide callback for location monitor address
   * @resource: Pointer to VME location monitor resource.
   * @monitor: Offset to which callback should be attached.
   * @callback: Pointer to callback function called when triggered.
   * @data: Generic pointer that will be passed to the callback function.
   *
   * Attach a callback to the specificed offset into the location monitors
   * monitored addresses. A generic pointer is provided to allow data to be
   * passed to the callback when called.
   *
   * Return: Zero on success, -EINVAL when provided with an invalid location
   *	   monitor resource or function is not supported. Hardware specific
   *	   errors may also be returned.
   */

  int vme_lm_attach(struct vme_resource *resource, int monitor,

  	void (*callback)(void *), void *data)

  {

  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_lm_resource *lm;

  	if (resource->type != VME_LM) {
  		printk(KERN_ERR "Not a Location Monitor resource
  ");

  		return -EINVAL;
  	}

  	lm = list_entry(resource->entry, struct vme_lm_resource, list);

  	if (!bridge->lm_attach) {

  		printk(KERN_ERR "vme_lm_attach not supported
  ");

  		return -EINVAL;
  	}

  	return bridge->lm_attach(lm, monitor, callback, data);

  }
  EXPORT_SYMBOL(vme_lm_attach);

  /**
   * vme_lm_detach - Remove callback for location monitor address
   * @resource: Pointer to VME location monitor resource.
   * @monitor: Offset to which callback should be removed.
   *
   * Remove the callback associated with the specificed offset into the
   * location monitors monitored addresses.
   *
   * Return: Zero on success, -EINVAL when provided with an invalid location
   *	   monitor resource or function is not supported. Hardware specific
   *	   errors may also be returned.
   */

  int vme_lm_detach(struct vme_resource *resource, int monitor)

  {

  	struct vme_bridge *bridge = find_bridge(resource);
  	struct vme_lm_resource *lm;

  	if (resource->type != VME_LM) {
  		printk(KERN_ERR "Not a Location Monitor resource
  ");

  		return -EINVAL;
  	}

  	lm = list_entry(resource->entry, struct vme_lm_resource, list);

  	if (!bridge->lm_detach) {

  		printk(KERN_ERR "vme_lm_detach not supported
  ");

  		return -EINVAL;
  	}

  	return bridge->lm_detach(lm, monitor);

  }
  EXPORT_SYMBOL(vme_lm_detach);

  /**
   * vme_lm_free - Free allocated VME location monitor
   * @resource: Pointer to VME location monitor resource.
   *
   * Free allocation of a VME location monitor.
   *
   * WARNING: This function currently expects that any callbacks that have
   *          been attached to the location monitor have been removed.
   *
   * Return: Zero on success, -EINVAL when provided with an invalid location
   *	   monitor resource.
   */

  void vme_lm_free(struct vme_resource *resource)
  {
  	struct vme_lm_resource *lm;
  
  	if (resource->type != VME_LM) {
  		printk(KERN_ERR "Not a Location Monitor resource
  ");
  		return;
  	}
  
  	lm = list_entry(resource->entry, struct vme_lm_resource, list);

  	mutex_lock(&lm->mtx);

  	/* XXX
  	 * Check to see that there aren't any callbacks still attached, if
  	 * there are we should probably be detaching them!
  	 */

  
  	lm->locked = 0;

  	mutex_unlock(&lm->mtx);

  
  	kfree(resource);

  }
  EXPORT_SYMBOL(vme_lm_free);

  /**
   * vme_slot_num - Retrieve slot ID
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   *
   * Retrieve the slot ID associated with the provided VME device.
   *
   * Return: The slot ID on success, -EINVAL if VME bridge cannot be determined
   *         or the function is not supported. Hardware specific errors may also
   *         be returned.
   */

  int vme_slot_num(struct vme_dev *vdev)

  {
  	struct vme_bridge *bridge;

  	bridge = vdev->bridge;

  	if (!bridge) {

  		printk(KERN_ERR "Can't find VME bus
  ");
  		return -EINVAL;
  	}

  	if (!bridge->slot_get) {

  		printk(KERN_WARNING "vme_slot_num not supported
  ");

  		return -EINVAL;
  	}

  	return bridge->slot_get(bridge);

  }

  EXPORT_SYMBOL(vme_slot_num);

  /**
   * vme_bus_num - Retrieve bus number
   * @vdev: Pointer to VME device struct vme_dev assigned to driver instance.
   *
   * Retrieve the bus enumeration associated with the provided VME device.
   *
   * Return: The bus number on success, -EINVAL if VME bridge cannot be
   *         determined.
   */

  int vme_bus_num(struct vme_dev *vdev)
  {
  	struct vme_bridge *bridge;
  
  	bridge = vdev->bridge;

  	if (!bridge) {

  		pr_err("Can't find VME bus
  ");
  		return -EINVAL;
  	}
  
  	return bridge->num;
  }
  EXPORT_SYMBOL(vme_bus_num);

  
  /* - Bridge Registration --------------------------------------------------- */

  static void vme_dev_release(struct device *dev)
  {
  	kfree(dev_to_vme_dev(dev));
  }

  /* Common bridge initialization */
  struct vme_bridge *vme_init_bridge(struct vme_bridge *bridge)
  {
  	INIT_LIST_HEAD(&bridge->vme_error_handlers);
  	INIT_LIST_HEAD(&bridge->master_resources);
  	INIT_LIST_HEAD(&bridge->slave_resources);
  	INIT_LIST_HEAD(&bridge->dma_resources);
  	INIT_LIST_HEAD(&bridge->lm_resources);
  	mutex_init(&bridge->irq_mtx);
  
  	return bridge;
  }
  EXPORT_SYMBOL(vme_init_bridge);

  int vme_register_bridge(struct vme_bridge *bridge)

  {
  	int i;

  	int ret = -1;

  	mutex_lock(&vme_buses_lock);

  	for (i = 0; i < sizeof(vme_bus_numbers) * 8; i++) {

  		if ((vme_bus_numbers & (1 << i)) == 0) {
  			vme_bus_numbers |= (1 << i);
  			bridge->num = i;

  			INIT_LIST_HEAD(&bridge->devices);

  			list_add_tail(&bridge->bus_list, &vme_bus_list);
  			ret = 0;

  			break;
  		}
  	}

  	mutex_unlock(&vme_buses_lock);

  	return ret;

  }

  EXPORT_SYMBOL(vme_register_bridge);

  void vme_unregister_bridge(struct vme_bridge *bridge)

  {

  	struct vme_dev *vdev;
  	struct vme_dev *tmp;

  	mutex_lock(&vme_buses_lock);
  	vme_bus_numbers &= ~(1 << bridge->num);

  	list_for_each_entry_safe(vdev, tmp, &bridge->devices, bridge_list) {
  		list_del(&vdev->drv_list);
  		list_del(&vdev->bridge_list);
  		device_unregister(&vdev->dev);
  	}

  	list_del(&bridge->bus_list);
  	mutex_unlock(&vme_buses_lock);

  }

  EXPORT_SYMBOL(vme_unregister_bridge);

  /* - Driver Registration --------------------------------------------------- */
  
  static int __vme_register_driver_bus(struct vme_driver *drv,
  	struct vme_bridge *bridge, unsigned int ndevs)
  {
  	int err;
  	unsigned int i;
  	struct vme_dev *vdev;
  	struct vme_dev *tmp;
  
  	for (i = 0; i < ndevs; i++) {

  		vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);

  		if (!vdev) {
  			err = -ENOMEM;

  			goto err_devalloc;
  		}

  		vdev->num = i;

  		vdev->bridge = bridge;

  		vdev->dev.platform_data = drv;
  		vdev->dev.release = vme_dev_release;

  		vdev->dev.parent = bridge->parent;
  		vdev->dev.bus = &vme_bus_type;

  		dev_set_name(&vdev->dev, "%s.%u-%u", drv->name, bridge->num,
  			vdev->num);

  		err = device_register(&vdev->dev);
  		if (err)

  			goto err_reg;

  		if (vdev->dev.platform_data) {
  			list_add_tail(&vdev->drv_list, &drv->devices);
  			list_add_tail(&vdev->bridge_list, &bridge->devices);
  		} else
  			device_unregister(&vdev->dev);
  	}
  	return 0;

  err_reg:

  	put_device(&vdev->dev);

  err_devalloc:

  	list_for_each_entry_safe(vdev, tmp, &drv->devices, drv_list) {
  		list_del(&vdev->drv_list);
  		list_del(&vdev->bridge_list);

  		device_unregister(&vdev->dev);

  	}

  	return err;

  }

  static int __vme_register_driver(struct vme_driver *drv, unsigned int ndevs)

  {

  	struct vme_bridge *bridge;
  	int err = 0;