cpqphp_ctrl.c

/*
 * Compaq Hot Plug Controller Driver
 *
 * Copyright (C) 1995,2001 Compaq Computer Corporation
 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2001 IBM Corp.
 *
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * 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, GOOD TITLE or
 * NON INFRINGEMENT.  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Send feedback to <greg@kroah.com>
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/kthread.h>
#include "cpqphp.h"

static u32 configure_new_device(struct controller* ctrl, struct pci_func *func,
			u8 behind_bridge, struct resource_lists *resources);
static int configure_new_function(struct controller* ctrl, struct pci_func *func,
			u8 behind_bridge, struct resource_lists *resources);
static void interrupt_event_handler(struct controller *ctrl);


static struct task_struct *cpqhp_event_thread;
static unsigned long pushbutton_pending;	/* = 0 */

/* delay is in jiffies to wait for */
static void long_delay(int delay)
{
	/*
	 * XXX(hch): if someone is bored please convert all callers
	 * to call msleep_interruptible directly.  They really want
	 * to specify timeouts in natural units and spend a lot of
	 * effort converting them to jiffies..
	 */
	msleep_interruptible(jiffies_to_msecs(delay));
}


/* FIXME: The following line needs to be somewhere else... */
#define WRONG_BUS_FREQUENCY 0x07
static u8 handle_switch_change(u8 change, struct controller * ctrl)
{
	int hp_slot;
	u8 rc = 0;
	u16 temp_word;
	struct pci_func *func;
	struct event_info *taskInfo;

	if (!change)
		return 0;

	/* Switch Change */
	dbg("cpqsbd:  Switch interrupt received.\n");

	for (hp_slot = 0; hp_slot < 6; hp_slot++) {
		if (change & (0x1L << hp_slot)) {
			/*
			 * this one changed.
			 */
			func = cpqhp_slot_find(ctrl->bus,
				(hp_slot + ctrl->slot_device_offset), 0);

			/* this is the structure that tells the worker thread
			 * what to do
			 */
			taskInfo = &(ctrl->event_queue[ctrl->next_event]);
			ctrl->next_event = (ctrl->next_event + 1) % 10;
			taskInfo->hp_slot = hp_slot;

			rc++;

			temp_word = ctrl->ctrl_int_comp >> 16;
			func->presence_save = (temp_word >> hp_slot) & 0x01;
			func->presence_save |= (temp_word >> (hp_slot + 7)) & 0x02;

			if (ctrl->ctrl_int_comp & (0x1L << hp_slot)) {
				/*
				 * Switch opened
				 */

				func->switch_save = 0;

				taskInfo->event_type = INT_SWITCH_OPEN;
			} else {
				/*
				 * Switch closed
				 */

				func->switch_save = 0x10;

				taskInfo->event_type = INT_SWITCH_CLOSE;
			}
		}
	}

	return rc;
}

/**
 * cpqhp_find_slot - find the struct slot of given device
 * @ctrl: scan lots of this controller
 * @device: the device id to find
 */
static struct slot *cpqhp_find_slot(struct controller *ctrl, u8 device)
{
	struct slot *slot = ctrl->slot;

	while (slot && (slot->device != device))
		slot = slot->next;

	return slot;
}


static u8 handle_presence_change(u16 change, struct controller * ctrl)
{
	int hp_slot;
	u8 rc = 0;
	u8 temp_byte;
	u16 temp_word;
	struct pci_func *func;
	struct event_info *taskInfo;
	struct slot *p_slot;

	if (!change)
		return 0;

	/*
	 * Presence Change
	 */
	dbg("cpqsbd:  Presence/Notify input change.\n");
	dbg("         Changed bits are 0x%4.4x\n", change );

	for (hp_slot = 0; hp_slot < 6; hp_slot++) {
		if (change & (0x0101 << hp_slot)) {
			/*
			 * this one changed.
			 */
			func = cpqhp_slot_find(ctrl->bus,
				(hp_slot + ctrl->slot_device_offset), 0);

			taskInfo = &(ctrl->event_queue[ctrl->next_event]);
			ctrl->next_event = (ctrl->next_event + 1) % 10;
			taskInfo->hp_slot = hp_slot;

			rc++;

			p_slot = cpqhp_find_slot(ctrl, hp_slot + (readb(ctrl->hpc_reg + SLOT_MASK) >> 4));
			if (!p_slot)
				return 0;

			/* If the switch closed, must be a button
			 * If not in button mode, nevermind
			 */
			if (func->switch_save && (ctrl->push_button == 1)) {
				temp_word = ctrl->ctrl_int_comp >> 16;
				temp_byte = (temp_word >> hp_slot) & 0x01;
				temp_byte |= (temp_word >> (hp_slot + 7)) & 0x02;

				if (temp_byte != func->presence_save) {
					/*
					 * button Pressed (doesn't do anything)
					 */
					dbg("hp_slot %d button pressed\n", hp_slot);
					taskInfo->event_type = INT_BUTTON_PRESS;
				} else {
					/*
					 * button Released - TAKE ACTION!!!!
					 */
					dbg("hp_slot %d button released\n", hp_slot);
					taskInfo->event_type = INT_BUTTON_RELEASE;

					/* Cancel if we are still blinking */
					if ((p_slot->state == BLINKINGON_STATE)
					    || (p_slot->state == BLINKINGOFF_STATE)) {
						taskInfo->event_type = INT_BUTTON_CANCEL;
						dbg("hp_slot %d button cancel\n", hp_slot);
					} else if ((p_slot->state == POWERON_STATE)
						   || (p_slot->state == POWEROFF_STATE)) {
						/* info(msg_button_ignore, p_slot->number); */
						taskInfo->event_type = INT_BUTTON_IGNORE;
						dbg("hp_slot %d button ignore\n", hp_slot);
					}
				}
			} else {
				/* Switch is open, assume a presence change
				 * Save the presence state
				 */
				temp_word = ctrl->ctrl_int_comp >> 16;
				func->presence_save = (temp_word >> hp_slot) & 0x01;
				func->presence_save |= (temp_word >> (hp_slot + 7)) & 0x02;

				if ((!(ctrl->ctrl_int_comp & (0x010000 << hp_slot))) ||
				    (!(ctrl->ctrl_int_comp & (0x01000000 << hp_slot)))) {
					/* Present */
					taskInfo->event_type = INT_PRESENCE_ON;
				} else {
					/* Not Present */
					taskInfo->event_type = INT_PRESENCE_OFF;
				}
			}
		}
	}

	return rc;
}


static u8 handle_power_fault(u8 change, struct controller * ctrl)
{
	int hp_slot;
	u8 rc = 0;
	struct pci_func *func;
	struct event_info *taskInfo;

	if (!change)
		return 0;

	/*
	 * power fault
	 */

	info("power fault interrupt\n");

	for (hp_slot = 0; hp_slot < 6; hp_slot++) {
		if (change & (0x01 << hp_slot)) {
			/*
			 * this one changed.
			 */
			func = cpqhp_slot_find(ctrl->bus,
				(hp_slot + ctrl->slot_device_offset), 0);

			taskInfo = &(ctrl->event_queue[ctrl->next_event]);
			ctrl->next_event = (ctrl->next_event + 1) % 10;
			taskInfo->hp_slot = hp_slot;

			rc++;

			if (ctrl->ctrl_int_comp & (0x00000100 << hp_slot)) {
				/*
				 * power fault Cleared
				 */
				func->status = 0x00;

				taskInfo->event_type = INT_POWER_FAULT_CLEAR;
			} else {
				/*
				 * power fault
				 */
				taskInfo->event_type = INT_POWER_FAULT;

				if (ctrl->rev < 4) {
					amber_LED_on (ctrl, hp_slot);
					green_LED_off (ctrl, hp_slot);
					set_SOGO (ctrl);

					/* this is a fatal condition, we want
					 * to crash the machine to protect from
					 * data corruption. simulated_NMI
					 * shouldn't ever return */
					/* FIXME
					simulated_NMI(hp_slot, ctrl); */

					/* The following code causes a software
					 * crash just in case simulated_NMI did
					 * return */
					/*FIXME
					panic(msg_power_fault); */
				} else {
					/* set power fault status for this board */
					func->status = 0xFF;
					info("power fault bit %x set\n", hp_slot);
				}
			}
		}
	}

	return rc;
}


/**
 * sort_by_size - sort nodes on the list by their length, smallest first.
 * @head: list to sort
 */
static int sort_by_size(struct pci_resource **head)
{
	struct pci_resource *current_res;
	struct pci_resource *next_res;
	int out_of_order = 1;

	if (!(*head))
		return 1;

	if (!((*head)->next))
		return 0;

	while (out_of_order) {
		out_of_order = 0;

		/* Special case for swapping list head */
		if (((*head)->next) &&
		    ((*head)->length > (*head)->next->length)) {
			out_of_order++;
			current_res = *head;
			*head = (*head)->next;
			current_res->next = (*head)->next;
			(*head)->next = current_res;
		}

		current_res = *head;

		while (current_res->next && current_res->next->next) {
			if (current_res->next->length > current_res->next->next->length) {
				out_of_order++;
				next_res = current_res->next;
				current_res->next = current_res->next->next;
				current_res = current_res->next;
				next_res->next = current_res->next;
				current_res->next = next_res;
			} else
				current_res = current_res->next;
		}
	}  /* End of out_of_order loop */

	return 0;
}


/**
 * sort_by_max_size - sort nodes on the list by their length, largest first.
 * @head: list to sort
 */
static int sort_by_max_size(struct pci_resource **head)
{
	struct pci_resource *current_res;
	struct pci_resource *next_res;
	int out_of_order = 1;

	if (!(*head))
		return 1;

	if (!((*head)->next))
		return 0;

	while (out_of_order) {
		out_of_order = 0;

		/* Special case for swapping list head */
		if (((*head)->next) &&
		    ((*head)->length < (*head)->next->length)) {
			out_of_order++;
			current_res = *head;
			*head = (*head)->next;
			current_res->next = (*head)->next;
			(*head)->next = current_res;
		}

		current_res = *head;

		while (current_res->next && current_res->next->next) {
			if (current_res->next->length < current_res->next->next->length) {
				out_of_order++;
				next_res = current_res->next;
				current_res->next = current_res->next->next;
				current_res = current_res->next;
				next_res->next = current_res->next;
				current_res->next = next_res;
			} else
				current_res = current_res->next;
		}
	}  /* End of out_of_order loop */

	return 0;
}


/**
 * do_pre_bridge_resource_split - find node of resources that are unused
 * @head: new list head
 * @orig_head: original list head
 * @alignment: max node size (?)
 */
static struct pci_resource *do_pre_bridge_resource_split(struct pci_resource **head,
				struct pci_resource **orig_head, u32 alignment)
{
	struct pci_resource *prevnode = NULL;
	struct pci_resource *node;
	struct pci_resource *split_node;
	u32 rc;
	u32 temp_dword;
	dbg("do_pre_bridge_resource_split\n");

	if (!(*head) || !(*orig_head))
		return NULL;

	rc = cpqhp_resource_sort_and_combine(head);

	if (rc)
		return NULL;

	if ((*head)->base != (*orig_head)->base)
		return NULL;

	if ((*head)->length == (*orig_head)->length)
		return NULL;


	/* If we got here, there the bridge requires some of the resource, but
	 * we may be able to split some off of the front
	 */

	node = *head;

	if (node->length & (alignment -1)) {
		/* this one isn't an aligned length, so we'll make a new entry
		 * and split it up.
		 */
		split_node = kmalloc(sizeof(*split_node), GFP_KERNEL);

		if (!split_node)
			return NULL;

		temp_dword = (node->length | (alignment-1)) + 1 - alignment;

		split_node->base = node->base;
		split_node->length = temp_dword;

		node->length -= temp_dword;
		node->base += split_node->length;

		/* Put it in the list */
		*head = split_node;
		split_node->next = node;
	}

	if (node->length < alignment)
		return NULL;

	/* Now unlink it */
	if (*head == node) {
		*head = node->next;
	} else {
		prevnode = *head;
		while (prevnode->next != node)
			prevnode = prevnode->next;

		prevnode->next = node->next;
	}
	node->next = NULL;

	return node;
}


/**
 * do_bridge_resource_split - find one node of resources that aren't in use
 * @head: list head
 * @alignment: max node size (?)
 */
static struct pci_resource *do_bridge_resource_split(struct pci_resource **head, u32 alignment)
{
	struct pci_resource *prevnode = NULL;
	struct pci_resource *node;
	u32 rc;
	u32 temp_dword;

	rc = cpqhp_resource_sort_and_combine(head);

	if (rc)
		return NULL;

	node = *head;

	while (node->next) {
		prevnode = node;
		node = node->next;
		kfree(prevnode);
	}

	if (node->length < alignment)
		goto error;

	if (node->base & (alignment - 1)) {
		/* Short circuit if adjusted size is too small */
		temp_dword = (node->base | (alignment-1)) + 1;
		if ((node->length - (temp_dword - node->base)) < alignment)
			goto error;

		node->length -= (temp_dword - node->base);
		node->base = temp_dword;
	}

	if (node->length & (alignment - 1))
		/* There's stuff in use after this node */
		goto error;

	return node;
error:
	kfree(node);
	return NULL;
}


/**
 * get_io_resource - find first node of given size not in ISA aliasing window.
 * @head: list to search
 * @size: size of node to find, must be a power of two.
 *
 * Description: This function sorts the resource list by size and then returns
 * returns the first node of "size" length that is not in the ISA aliasing
 * window.  If it finds a node larger than "size" it will split it up.
 */
static struct pci_resource *get_io_resource(struct pci_resource **head, u32 size)
{
	struct pci_resource *prevnode;
	struct pci_resource *node;
	struct pci_resource *split_node;
	u32 temp_dword;

	if (!(*head))
		return NULL;

	if (cpqhp_resource_sort_and_combine(head))
		return NULL;

	if (sort_by_size(head))
		return NULL;

	for (node = *head; node; node = node->next) {
		if (node->length < size)
			continue;

		if (node->base & (size - 1)) {
			/* this one isn't base aligned properly
			 * so we'll make a new entry and split it up
			 */
			temp_dword = (node->base | (size-1)) + 1;

			/* Short circuit if adjusted size is too small */
			if ((node->length - (temp_dword - node->base)) < size)
				continue;

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

			if (!split_node)
				return NULL;

			split_node->base = node->base;
			split_node->length = temp_dword - node->base;
			node->base = temp_dword;
			node->length -= split_node->length;

			/* Put it in the list */
			split_node->next = node->next;
			node->next = split_node;
		} /* End of non-aligned base */

		/* Don't need to check if too small since we already did */
		if (node->length > size) {
			/* this one is longer than we need
			 * so we'll make a new entry and split it up
			 */
			split_node = kmalloc(sizeof(*split_node), GFP_KERNEL);

			if (!split_node)
				return NULL;

			split_node->base = node->base + size;
			split_node->length = node->length - size;
			node->length = size;

			/* Put it in the list */
			split_node->next = node->next;
			node->next = split_node;
		}  /* End of too big on top end */

		/* For IO make sure it's not in the ISA aliasing space */
		if (node->base & 0x300L)
			continue;

		/* If we got here, then it is the right size
		 * Now take it out of the list and break
		 */
		if (*head == node) {
			*head = node->next;
		} else {
			prevnode = *head;
			while (prevnode->next != node)
				prevnode = prevnode->next;

			prevnode->next = node->next;
		}
		node->next = NULL;
		break;
	}

	return node;
}


/**
 * get_max_resource - get largest node which has at least the given size.
 * @head: the list to search the node in
 * @size: the minimum size of the node to find
 *
 * Description: Gets the largest node that is at least "size" big from the
 * list pointed to by head.  It aligns the node on top and bottom
 * to "size" alignment before returning it.
 */
static struct pci_resource *get_max_resource(struct pci_resource **head, u32 size)
{
	struct pci_resource *max;
	struct pci_resource *temp;
	struct pci_resource *split_node;
	u32 temp_dword;

	if (cpqhp_resource_sort_and_combine(head))
		return NULL;

	if (sort_by_max_size(head))
		return NULL;

	for (max = *head; max; max = max->next) {
		/* If not big enough we could probably just bail,
		 * instead we'll continue to the next.
		 */
		if (max->length < size)
			continue;

		if (max->base & (size - 1)) {
			/* this one isn't base aligned properly
			 * so we'll make a new entry and split it up
			 */
			temp_dword = (max->base | (size-1)) + 1;

			/* Short circuit if adjusted size is too small */
			if ((max->length - (temp_dword - max->base)) < size)
				continue;

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

			if (!split_node)
				return NULL;

			split_node->base = max->base;
			split_node->length = temp_dword - max->base;
			max->base = temp_dword;
			max->length -= split_node->length;

			split_node->next = max->next;
			max->next = split_node;
		}

		if ((max->base + max->length) & (size - 1)) {
			/* this one isn't end aligned properly at the top
			 * so we'll make a new entry and split it up
			 */
			split_node = kmalloc(sizeof(*split_node), GFP_KERNEL);

			if (!split_node)
				return NULL;
			temp_dword = ((max->base + max->length) & ~(size - 1));
			split_node->base = temp_dword;
			split_node->length = max->length + max->base
					     - split_node->base;
			max->length -= split_node->length;

			split_node->next = max->next;
			max->next = split_node;
		}

		/* Make sure it didn't shrink too much when we aligned it */
		if (max->length < size)
			continue;

		/* Now take it out of the list */
		temp = *head;
		if (temp == max) {
			*head = max->next;
		} else {
			while (temp && temp->next != max) {
				temp = temp->next;
			}

			temp->next = max->next;
		}

		max->next = NULL;
		break;
	}

	return max;
}


/**
 * get_resource - find resource of given size and split up larger ones.
 * @head: the list to search for resources
 * @size: the size limit to use
 *
 * Description: This function sorts the resource list by size and then
 * returns the first node of "size" length.  If it finds a node
 * larger than "size" it will split it up.
 *
 * size must be a power of two.
 */
static struct pci_resource *get_resource(struct pci_resource **head, u32 size)
{
	struct pci_resource *prevnode;
	struct pci_resource *node;
	struct pci_resource *split_node;
	u32 temp_dword;

	if (cpqhp_resource_sort_and_combine(head))
		return NULL;

	if (sort_by_size(head))
		return NULL;

	for (node = *head; node; node = node->next) {
		dbg("%s: req_size =%x node=%p, base=%x, length=%x\n",
		    __func__, size, node, node->base, node->length);
		if (node->length < size)
			continue;

		if (node->base & (size - 1)) {
			dbg("%s: not aligned\n", __func__);
			/* this one isn't base aligned properly
			 * so we'll make a new entry and split it up
			 */
			temp_dword = (node->base | (size-1)) + 1;

			/* Short circuit if adjusted size is too small */
			if ((node->length - (temp_dword - node->base)) < size)
				continue;

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

			if (!split_node)
				return NULL;

			split_node->base = node->base;
			split_node->length = temp_dword - node->base;
			node->base = temp_dword;
			node->length -= split_node->length;

			split_node->next = node->next;
			node->next = split_node;
		} /* End of non-aligned base */

		/* Don't need to check if too small since we already did */
		if (node->length > size) {
			dbg("%s: too big\n", __func__);
			/* this one is longer than we need
			 * so we'll make a new entry and split it up
			 */
			split_node = kmalloc(sizeof(*split_node), GFP_KERNEL);

			if (!split_node)
				return NULL;

			split_node->base = node->base + size;
			split_node->length = node->length - size;
			node->length = size;

			/* Put it in the list */
			split_node->next = node->next;
			node->next = split_node;
		}  /* End of too big on top end */

		dbg("%s: got one!!!\n", __func__);
		/* If we got here, then it is the right size
		 * Now take it out of the list */
		if (*head == node) {
			*head = node->next;
		} else {
			prevnode = *head;
			while (prevnode->next != node)
				prevnode = prevnode->next;

			prevnode->next = node->next;
		}
		node->next = NULL;
		break;
	}
	return node;
}


/**
 * cpqhp_resource_sort_and_combine - sort nodes by base addresses and clean up
 * @head: the list to sort and clean up
 *
 * Description: Sorts all of the nodes in the list in ascending order by
 * their base addresses.  Also does garbage collection by
 * combining adjacent nodes.
 *
 * Returns %0 if success.
 */
int cpqhp_resource_sort_and_combine(struct pci_resource **head)
{
	struct pci_resource *node1;
	struct pci_resource *node2;
	int out_of_order = 1;

	dbg("%s: head = %p, *head = %p\n", __func__, head, *head);

	if (!(*head))
		return 1;

	dbg("*head->next = %p\n",(*head)->next);

	if (!(*head)->next)
		return 0;	/* only one item on the list, already sorted! */

	dbg("*head->base = 0x%x\n",(*head)->base);
	dbg("*head->next->base = 0x%x\n",(*head)->next->base);
	while (out_of_order) {
		out_of_order = 0;

		/* Special case for swapping list head */
		if (((*head)->next) &&
		    ((*head)->base > (*head)->next->base)) {
			node1 = *head;
			(*head) = (*head)->next;
			node1->next = (*head)->next;
			(*head)->next = node1;
			out_of_order++;
		}

		node1 = (*head);

		while (node1->next && node1->next->next) {
			if (node1->next->base > node1->next->next->base) {
				out_of_order++;
				node2 = node1->next;
				node1->next = node1->next->next;
				node1 = node1->next;
				node2->next = node1->next;
				node1->next = node2;
			} else
				node1 = node1->next;
		}
	}  /* End of out_of_order loop */

	node1 = *head;

	while (node1 && node1->next) {
		if ((node1->base + node1->length) == node1->next->base) {
			/* Combine */
			dbg("8..\n");
			node1->length += node1->next->length;
			node2 = node1->next;
			node1->next = node1->next->next;
			kfree(node2);
		} else
			node1 = node1->next;
	}

	return 0;
}


irqreturn_t cpqhp_ctrl_intr(int IRQ, void *data)
{
	struct controller *ctrl = data;
	u8 schedule_flag = 0;
	u8 reset;
	u16 misc;
	u32 Diff;
	u32 temp_dword;


	misc = readw(ctrl->hpc_reg + MISC);
	/*
	 * Check to see if it was our interrupt
	 */
	if (!(misc & 0x000C)) {
		return IRQ_NONE;
	}

	if (misc & 0x0004) {
		/*
		 * Serial Output interrupt Pending
		 */

		/* Clear the interrupt */
		misc |= 0x0004;
		writew(misc, ctrl->hpc_reg + MISC);

		/* Read to clear posted writes */
		misc = readw(ctrl->hpc_reg + MISC);

		dbg ("%s - waking up\n", __func__);
		wake_up_interruptible(&ctrl->queue);
	}

	if (misc & 0x0008) {
		/* General-interrupt-input interrupt Pending */
		Diff = readl(ctrl->hpc_reg + INT_INPUT_CLEAR) ^ ctrl->ctrl_int_comp;

		ctrl->ctrl_int_comp = readl(ctrl->hpc_reg + INT_INPUT_CLEAR);

		/* Clear the interrupt */
		writel(Diff, ctrl->hpc_reg + INT_INPUT_CLEAR);

		/* Read it back to clear any posted writes */
		temp_dword = readl(ctrl->hpc_reg + INT_INPUT_CLEAR);

		if (!Diff)
			/* Clear all interrupts */
			writel(0xFFFFFFFF, ctrl->hpc_reg + INT_INPUT_CLEAR);

		schedule_flag += handle_switch_change((u8)(Diff & 0xFFL), ctrl);
		schedule_flag += handle_presence_change((u16)((Diff & 0xFFFF0000L) >> 16), ctrl);
		schedule_flag += handle_power_fault((u8)((Diff & 0xFF00L) >> 8), ctrl);
	}

	reset = readb(ctrl->hpc_reg + RESET_FREQ_MODE);
	if (reset & 0x40) {
		/* Bus reset has completed */
		reset &= 0xCF;
		writeb(reset, ctrl->hpc_reg + RESET_FREQ_MODE);
		reset = readb(ctrl->hpc_reg + RESET_FREQ_MODE);
		wake_up_interruptible(&ctrl->queue);
	}

	if (schedule_flag) {
		wake_up_process(cpqhp_event_thread);
		dbg("Waking even thread");
	}
	return IRQ_HANDLED;
}


/**
 * cpqhp_slot_create - Creates a node and adds it to the proper bus.
 * @busnumber: bus where new node is to be located
 *
 * Returns pointer to the new node or %NULL if unsuccessful.
 */
struct pci_func *cpqhp_slot_create(u8 busnumber)
{
	struct pci_func *new_slot;
	struct pci_func *next;

	new_slot = kzalloc(sizeof(*new_slot), GFP_KERNEL);
	if (new_slot == NULL)
		return new_slot;

	new_slot->next = NULL;
	new_slot->configured = 1;

	if (cpqhp_slot_list[busnumber] == NULL) {
		cpqhp_slot_list[busnumber] = new_slot;
	} else {
		next = cpqhp_slot_list[busnumber];
		while (next->next != NULL)
			next = next->next;
		next->next = new_slot;
	}
	return new_slot;
}


/**
 * slot_remove - Removes a node from the linked list of slots.
 * @old_slot: slot to remove
 *
 * Returns %0 if successful, !0 otherwise.
 */
static int slot_remove(struct pci_func * old_slot)
{