drivers/pci/hotplug/pciehp_ctrl.c - kernel/bruno - Git at Google

 /*
  * PCI Express 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.
  * Copyright (C) 2003-2004 Intel Corporation
  *
  * 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>, <kristen.c.accardi@intel.com>
  *
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/pci.h>
 #include "../pci.h"
 #include "pciehp.h"

 static void interrupt_event_handler(struct work_struct *work);

 void pciehp_queue_interrupt_event(struct slot *p_slot, u32 event_type)
 {
 	struct event_info *info;

 	info = kmalloc(sizeof(*info), GFP_ATOMIC);
 	if (!info) {
 		ctrl_err(p_slot->ctrl, "dropped event %d (ENOMEM)\n", event_type);
 		return;
 	}

 	INIT_WORK(&info->work, interrupt_event_handler);
 	info->event_type = event_type;
 	info->p_slot = p_slot;
 	queue_work(p_slot->wq, &info->work);
 }

 /* The following routines constitute the bulk of the
    hotplug controller logic
  */

 static void set_slot_off(struct controller *ctrl, struct slot *pslot)
 {
 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
 	if (POWER_CTRL(ctrl)) {
 		pciehp_power_off_slot(pslot);

 		/*
 		 * After turning power off, we must wait for at least 1 second
 		 * before taking any action that relies on power having been
 		 * removed from the slot/adapter.
 		 */
 		msleep(1000);
 	}

 	pciehp_green_led_off(pslot);
 	pciehp_set_attention_status(pslot, 1);
 }

 /**
  * board_added - Called after a board has been added to the system.
  * @p_slot: &slot where board is added
  *
  * Turns power on for the board.
  * Configures board.
  */
 static int board_added(struct slot *p_slot)
 {
 	int retval = 0;
 	struct controller *ctrl = p_slot->ctrl;
 	struct pci_bus *parent = ctrl->pcie->port->subordinate;

 	if (POWER_CTRL(ctrl)) {
 		/* Power on slot */
 		retval = pciehp_power_on_slot(p_slot);
 		if (retval)
 			return retval;
 	}

 	pciehp_green_led_blink(p_slot);

 	/* Check link training status */
 	retval = pciehp_check_link_status(ctrl);
 	if (retval) {
 		ctrl_err(ctrl, "Failed to check link status\n");
 		goto err_exit;
 	}

 	/* Check for a power fault */
 	if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
 		ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 		retval = -EIO;
 		goto err_exit;
 	}

 	retval = pciehp_configure_device(p_slot);
 	if (retval) {
 		ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
 			 pci_domain_nr(parent), parent->number);
 		if (retval != -EEXIST)
 			goto err_exit;
 	}

 	pciehp_green_led_on(p_slot);
 	return 0;

 err_exit:
 	set_slot_off(ctrl, p_slot);
 	return retval;
 }

 /**
  * remove_board - Turns off slot and LEDs
  * @p_slot: slot where board is being removed
  */
 static int remove_board(struct slot *p_slot)
 {
 	int retval;
 	struct controller *ctrl = p_slot->ctrl;

 	retval = pciehp_unconfigure_device(p_slot);
 	if (retval)
 		return retval;

 	if (POWER_CTRL(ctrl)) {
 		pciehp_power_off_slot(p_slot);

 		/*
 		 * After turning power off, we must wait for at least 1 second
 		 * before taking any action that relies on power having been
 		 * removed from the slot/adapter.
 		 */
 		msleep(1000);
 	}

 	/* turn off Green LED */
 	pciehp_green_led_off(p_slot);
 	return 0;
 }

 struct power_work_info {
 	struct slot *p_slot;
 	struct work_struct work;
 	unsigned int req;
 #define DISABLE_REQ 0
 #define ENABLE_REQ  1
 };

 /**
  * pciehp_power_thread - handle pushbutton events
  * @work: &struct work_struct describing work to be done
  *
  * Scheduled procedure to handle blocking stuff for the pushbuttons.
  * Handles all pending events and exits.
  */
 static void pciehp_power_thread(struct work_struct *work)
 {
 	struct power_work_info *info =
 		container_of(work, struct power_work_info, work);
 	struct slot *p_slot = info->p_slot;
 	int ret;

 	switch (info->req) {
 	case DISABLE_REQ:
 		mutex_lock(&p_slot->hotplug_lock);
 		pciehp_disable_slot(p_slot);
 		mutex_unlock(&p_slot->hotplug_lock);
 		mutex_lock(&p_slot->lock);
 		p_slot->state = STATIC_STATE;
 		mutex_unlock(&p_slot->lock);
 		break;
 	case ENABLE_REQ:
 		mutex_lock(&p_slot->hotplug_lock);
 		ret = pciehp_enable_slot(p_slot);
 		mutex_unlock(&p_slot->hotplug_lock);
 		if (ret)
 			pciehp_green_led_off(p_slot);
 		mutex_lock(&p_slot->lock);
 		p_slot->state = STATIC_STATE;
 		mutex_unlock(&p_slot->lock);
 		break;
 	default:
 		break;
 	}

 	kfree(info);
 }

 static void pciehp_queue_power_work(struct slot *p_slot, int req)
 {
 	struct power_work_info *info;

 	p_slot->state = (req == ENABLE_REQ) ? POWERON_STATE : POWEROFF_STATE;

 	info = kmalloc(sizeof(*info), GFP_KERNEL);
 	if (!info) {
 		ctrl_err(p_slot->ctrl, "no memory to queue %s request\n",
 			 (req == ENABLE_REQ) ? "poweron" : "poweroff");
 		return;
 	}
 	info->p_slot = p_slot;
 	INIT_WORK(&info->work, pciehp_power_thread);
 	info->req = req;
 	queue_work(p_slot->wq, &info->work);
 }

 void pciehp_queue_pushbutton_work(struct work_struct *work)
 {
 	struct slot *p_slot = container_of(work, struct slot, work.work);

 	mutex_lock(&p_slot->lock);
 	switch (p_slot->state) {
 	case BLINKINGOFF_STATE:
 		pciehp_queue_power_work(p_slot, DISABLE_REQ);
 		break;
 	case BLINKINGON_STATE:
 		pciehp_queue_power_work(p_slot, ENABLE_REQ);
 		break;
 	default:
 		break;
 	}
 	mutex_unlock(&p_slot->lock);
 }

 /*
  * Note: This function must be called with slot->lock held
  */
 static void handle_button_press_event(struct slot *p_slot)
 {
 	struct controller *ctrl = p_slot->ctrl;
 	u8 getstatus;

 	switch (p_slot->state) {
 	case STATIC_STATE:
 		pciehp_get_power_status(p_slot, &getstatus);
 		if (getstatus) {
 			p_slot->state = BLINKINGOFF_STATE;
 			ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
 				  slot_name(p_slot));
 		} else {
 			p_slot->state = BLINKINGON_STATE;
 			ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
 				  slot_name(p_slot));
 		}
 		/* blink green LED and turn off amber */
 		pciehp_green_led_blink(p_slot);
 		pciehp_set_attention_status(p_slot, 0);
 		queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
 		break;
 	case BLINKINGOFF_STATE:
 	case BLINKINGON_STATE:
 		/*
 		 * Cancel if we are still blinking; this means that we
 		 * press the attention again before the 5 sec. limit
 		 * expires to cancel hot-add or hot-remove
 		 */
 		ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
 		cancel_delayed_work(&p_slot->work);
 		if (p_slot->state == BLINKINGOFF_STATE)
 			pciehp_green_led_on(p_slot);
 		else
 			pciehp_green_led_off(p_slot);
 		pciehp_set_attention_status(p_slot, 0);
 		ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
 			  slot_name(p_slot));
 		p_slot->state = STATIC_STATE;
 		break;
 	case POWEROFF_STATE:
 	case POWERON_STATE:
 		/*
 		 * Ignore if the slot is on power-on or power-off state;
 		 * this means that the previous attention button action
 		 * to hot-add or hot-remove is undergoing
 		 */
 		ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
 		break;
 	default:
 		ctrl_warn(ctrl, "ignoring invalid state %#x\n", p_slot->state);
 		break;
 	}
 }

 /*
  * Note: This function must be called with slot->lock held
  */
 static void handle_surprise_event(struct slot *p_slot)
 {
 	u8 getstatus;

 	pciehp_get_adapter_status(p_slot, &getstatus);
 	if (!getstatus)
 		pciehp_queue_power_work(p_slot, DISABLE_REQ);
 	else
 		pciehp_queue_power_work(p_slot, ENABLE_REQ);
 }

 /*
  * Note: This function must be called with slot->lock held
  */
 static void handle_link_event(struct slot *p_slot, u32 event)
 {
 	struct controller *ctrl = p_slot->ctrl;

 	switch (p_slot->state) {
 	case BLINKINGON_STATE:
 	case BLINKINGOFF_STATE:
 		cancel_delayed_work(&p_slot->work);
 		/* Fall through */
 	case STATIC_STATE:
 		pciehp_queue_power_work(p_slot, event == INT_LINK_UP ?
 					ENABLE_REQ : DISABLE_REQ);
 		break;
 	case POWERON_STATE:
 		if (event == INT_LINK_UP) {
 			ctrl_info(ctrl,
 				  "Link Up event ignored on slot(%s): already powering on\n",
 				  slot_name(p_slot));
 		} else {
 			ctrl_info(ctrl,
 				  "Link Down event queued on slot(%s): currently getting powered on\n",
 				  slot_name(p_slot));
 			pciehp_queue_power_work(p_slot, DISABLE_REQ);
 		}
 		break;
 	case POWEROFF_STATE:
 		if (event == INT_LINK_UP) {
 			ctrl_info(ctrl,
 				  "Link Up event queued on slot(%s): currently getting powered off\n",
 				  slot_name(p_slot));
 			pciehp_queue_power_work(p_slot, ENABLE_REQ);
 		} else {
 			ctrl_info(ctrl,
 				  "Link Down event ignored on slot(%s): already powering off\n",
 				  slot_name(p_slot));
 		}
 		break;
 	default:
 		ctrl_err(ctrl, "ignoring invalid state %#x on slot(%s)\n",
 			 p_slot->state, slot_name(p_slot));
 		break;
 	}
 }

 static void interrupt_event_handler(struct work_struct *work)
 {
 	struct event_info *info = container_of(work, struct event_info, work);
 	struct slot *p_slot = info->p_slot;
 	struct controller *ctrl = p_slot->ctrl;

 	mutex_lock(&p_slot->lock);
 	switch (info->event_type) {
 	case INT_BUTTON_PRESS:
 		handle_button_press_event(p_slot);
 		break;
 	case INT_POWER_FAULT:
 		if (!POWER_CTRL(ctrl))
 			break;
 		pciehp_set_attention_status(p_slot, 1);
 		pciehp_green_led_off(p_slot);
 		break;
 	case INT_PRESENCE_ON:
 		handle_surprise_event(p_slot);
 		break;
 	case INT_PRESENCE_OFF:
 		/*
 		 * Regardless of surprise capability, we need to
 		 * definitely remove a card that has been pulled out!
 		 */
 		handle_surprise_event(p_slot);
 		break;
 	case INT_LINK_UP:
 	case INT_LINK_DOWN:
 		handle_link_event(p_slot, info->event_type);
 		break;
 	default:
 		break;
 	}
 	mutex_unlock(&p_slot->lock);

 	kfree(info);
 }

 /*
  * Note: This function must be called with slot->hotplug_lock held
  */
 int pciehp_enable_slot(struct slot *p_slot)
 {
 	u8 getstatus = 0;
 	int rc;
 	struct controller *ctrl = p_slot->ctrl;

 	pciehp_get_adapter_status(p_slot, &getstatus);
 	if (!getstatus) {
 		ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
 		return -ENODEV;
 	}
 	if (MRL_SENS(p_slot->ctrl)) {
 		pciehp_get_latch_status(p_slot, &getstatus);
 		if (getstatus) {
 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
 				  slot_name(p_slot));
 			return -ENODEV;
 		}
 	}

 	if (POWER_CTRL(p_slot->ctrl)) {
 		pciehp_get_power_status(p_slot, &getstatus);
 		if (getstatus) {
 			ctrl_info(ctrl, "Already enabled on slot(%s)\n",
 				  slot_name(p_slot));
 			return -EINVAL;
 		}
 	}

 	pciehp_get_latch_status(p_slot, &getstatus);

 	rc = board_added(p_slot);
 	if (rc)
 		pciehp_get_latch_status(p_slot, &getstatus);

 	return rc;
 }

 /*
  * Note: This function must be called with slot->hotplug_lock held
  */
 int pciehp_disable_slot(struct slot *p_slot)
 {
 	u8 getstatus = 0;
 	struct controller *ctrl = p_slot->ctrl;

 	if (!p_slot->ctrl)
 		return 1;

 	if (POWER_CTRL(p_slot->ctrl)) {
 		pciehp_get_power_status(p_slot, &getstatus);
 		if (!getstatus) {
 			ctrl_info(ctrl, "Already disabled on slot(%s)\n",
 				  slot_name(p_slot));
 			return -EINVAL;
 		}
 	}

 	return remove_board(p_slot);
 }

 int pciehp_sysfs_enable_slot(struct slot *p_slot)
 {
 	int retval = -ENODEV;
 	struct controller *ctrl = p_slot->ctrl;

 	mutex_lock(&p_slot->lock);
 	switch (p_slot->state) {
 	case BLINKINGON_STATE:
 		cancel_delayed_work(&p_slot->work);
 	case STATIC_STATE:
 		p_slot->state = POWERON_STATE;
 		mutex_unlock(&p_slot->lock);
 		mutex_lock(&p_slot->hotplug_lock);
 		retval = pciehp_enable_slot(p_slot);
 		mutex_unlock(&p_slot->hotplug_lock);
 		mutex_lock(&p_slot->lock);
 		p_slot->state = STATIC_STATE;
 		break;
 	case POWERON_STATE:
 		ctrl_info(ctrl, "Slot %s is already in powering on state\n",
 			  slot_name(p_slot));
 		break;
 	case BLINKINGOFF_STATE:
 	case POWEROFF_STATE:
 		ctrl_info(ctrl, "Already enabled on slot %s\n",
 			  slot_name(p_slot));
 		break;
 	default:
 		ctrl_err(ctrl, "invalid state %#x on slot %s\n",
 			 p_slot->state, slot_name(p_slot));
 		break;
 	}
 	mutex_unlock(&p_slot->lock);

 	return retval;
 }

 int pciehp_sysfs_disable_slot(struct slot *p_slot)
 {
 	int retval = -ENODEV;
 	struct controller *ctrl = p_slot->ctrl;

 	mutex_lock(&p_slot->lock);
 	switch (p_slot->state) {
 	case BLINKINGOFF_STATE:
 		cancel_delayed_work(&p_slot->work);
 	case STATIC_STATE:
 		p_slot->state = POWEROFF_STATE;
 		mutex_unlock(&p_slot->lock);
 		retval = pciehp_disable_slot(p_slot);
 		mutex_lock(&p_slot->lock);
 		p_slot->state = STATIC_STATE;
 		break;
 	case POWEROFF_STATE:
 		ctrl_info(ctrl, "Slot %s is already in powering off state\n",
 			  slot_name(p_slot));
 		break;
 	case BLINKINGON_STATE:
 	case POWERON_STATE:
 		ctrl_info(ctrl, "Already disabled on slot %s\n",
 			  slot_name(p_slot));
 		break;
 	default:
 		ctrl_err(ctrl, "invalid state %#x on slot %s\n",
 			 p_slot->state, slot_name(p_slot));
 		break;
 	}
 	mutex_unlock(&p_slot->lock);

 	return retval;
 }
	/*
	* PCI Express 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.
	* Copyright (C) 2003-2004 Intel Corporation
	*
	* 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>, <kristen.c.accardi@intel.com>
	*
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/types.h>
	#include <linux/slab.h>
	#include <linux/pci.h>
	#include "../pci.h"
	#include "pciehp.h"

	static void interrupt_event_handler(struct work_struct *work);

	void pciehp_queue_interrupt_event(struct slot *p_slot, u32 event_type)
	{
	struct event_info *info;

	info = kmalloc(sizeof(*info), GFP_ATOMIC);
	if (!info) {
	ctrl_err(p_slot->ctrl, "dropped event %d (ENOMEM)\n", event_type);
	return;
	}

	INIT_WORK(&info->work, interrupt_event_handler);
	info->event_type = event_type;
	info->p_slot = p_slot;
	queue_work(p_slot->wq, &info->work);
	}

	/* The following routines constitute the bulk of the
	hotplug controller logic
	*/

	static void set_slot_off(struct controller ctrl, struct slot pslot)
	{
	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
	if (POWER_CTRL(ctrl)) {
	pciehp_power_off_slot(pslot);

	/*
	* After turning power off, we must wait for at least 1 second
	* before taking any action that relies on power having been
	* removed from the slot/adapter.
	*/
	msleep(1000);
	}

	pciehp_green_led_off(pslot);
	pciehp_set_attention_status(pslot, 1);
	}

	/**
	* board_added - Called after a board has been added to the system.
	* @p_slot: &slot where board is added
	*
	* Turns power on for the board.
	* Configures board.
	*/
	static int board_added(struct slot *p_slot)
	{
	int retval = 0;
	struct controller *ctrl = p_slot->ctrl;
	struct pci_bus *parent = ctrl->pcie->port->subordinate;

	if (POWER_CTRL(ctrl)) {
	/* Power on slot */
	retval = pciehp_power_on_slot(p_slot);
	if (retval)
	return retval;
	}

	pciehp_green_led_blink(p_slot);

	/* Check link training status */
	retval = pciehp_check_link_status(ctrl);
	if (retval) {
	ctrl_err(ctrl, "Failed to check link status\n");
	goto err_exit;
	}

	/* Check for a power fault */
	if (ctrl->power_fault_detected \|\| pciehp_query_power_fault(p_slot)) {
	ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
	retval = -EIO;
	goto err_exit;
	}

	retval = pciehp_configure_device(p_slot);
	if (retval) {
	ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
	pci_domain_nr(parent), parent->number);
	if (retval != -EEXIST)
	goto err_exit;
	}

	pciehp_green_led_on(p_slot);
	return 0;

	err_exit:
	set_slot_off(ctrl, p_slot);
	return retval;
	}

	/**
	* remove_board - Turns off slot and LEDs
	* @p_slot: slot where board is being removed
	*/
	static int remove_board(struct slot *p_slot)
	{
	int retval;
	struct controller *ctrl = p_slot->ctrl;

	retval = pciehp_unconfigure_device(p_slot);
	if (retval)
	return retval;

	if (POWER_CTRL(ctrl)) {
	pciehp_power_off_slot(p_slot);

	/*
	* After turning power off, we must wait for at least 1 second
	* before taking any action that relies on power having been
	* removed from the slot/adapter.
	*/
	msleep(1000);
	}

	/* turn off Green LED */
	pciehp_green_led_off(p_slot);
	return 0;
	}

	struct power_work_info {
	struct slot *p_slot;
	struct work_struct work;
	unsigned int req;
	#define DISABLE_REQ 0
	#define ENABLE_REQ 1
	};

	/**
	* pciehp_power_thread - handle pushbutton events
	* @work: &struct work_struct describing work to be done
	*
	* Scheduled procedure to handle blocking stuff for the pushbuttons.
	* Handles all pending events and exits.
	*/
	static void pciehp_power_thread(struct work_struct *work)
	{
	struct power_work_info *info =
	container_of(work, struct power_work_info, work);
	struct slot *p_slot = info->p_slot;
	int ret;

	switch (info->req) {
	case DISABLE_REQ:
	mutex_lock(&p_slot->hotplug_lock);
	pciehp_disable_slot(p_slot);
	mutex_unlock(&p_slot->hotplug_lock);
	mutex_lock(&p_slot->lock);
	p_slot->state = STATIC_STATE;
	mutex_unlock(&p_slot->lock);
	break;
	case ENABLE_REQ:
	mutex_lock(&p_slot->hotplug_lock);
	ret = pciehp_enable_slot(p_slot);
	mutex_unlock(&p_slot->hotplug_lock);
	if (ret)
	pciehp_green_led_off(p_slot);
	mutex_lock(&p_slot->lock);
	p_slot->state = STATIC_STATE;
	mutex_unlock(&p_slot->lock);
	break;
	default:
	break;
	}

	kfree(info);
	}

	static void pciehp_queue_power_work(struct slot *p_slot, int req)
	{
	struct power_work_info *info;

	p_slot->state = (req == ENABLE_REQ) ? POWERON_STATE : POWEROFF_STATE;

	info = kmalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
	ctrl_err(p_slot->ctrl, "no memory to queue %s request\n",
	(req == ENABLE_REQ) ? "poweron" : "poweroff");
	return;
	}
	info->p_slot = p_slot;
	INIT_WORK(&info->work, pciehp_power_thread);
	info->req = req;
	queue_work(p_slot->wq, &info->work);
	}

	void pciehp_queue_pushbutton_work(struct work_struct *work)
	{
	struct slot *p_slot = container_of(work, struct slot, work.work);

	mutex_lock(&p_slot->lock);
	switch (p_slot->state) {
	case BLINKINGOFF_STATE:
	pciehp_queue_power_work(p_slot, DISABLE_REQ);
	break;
	case BLINKINGON_STATE:
	pciehp_queue_power_work(p_slot, ENABLE_REQ);
	break;
	default:
	break;
	}
	mutex_unlock(&p_slot->lock);
	}

	/*
	* Note: This function must be called with slot->lock held
	*/
	static void handle_button_press_event(struct slot *p_slot)
	{
	struct controller *ctrl = p_slot->ctrl;
	u8 getstatus;

	switch (p_slot->state) {
	case STATIC_STATE:
	pciehp_get_power_status(p_slot, &getstatus);
	if (getstatus) {
	p_slot->state = BLINKINGOFF_STATE;
	ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
	slot_name(p_slot));
	} else {
	p_slot->state = BLINKINGON_STATE;
	ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
	slot_name(p_slot));
	}
	/* blink green LED and turn off amber */
	pciehp_green_led_blink(p_slot);
	pciehp_set_attention_status(p_slot, 0);
	queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
	break;
	case BLINKINGOFF_STATE:
	case BLINKINGON_STATE:
	/*
	* Cancel if we are still blinking; this means that we
	* press the attention again before the 5 sec. limit
	* expires to cancel hot-add or hot-remove
	*/
	ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
	cancel_delayed_work(&p_slot->work);
	if (p_slot->state == BLINKINGOFF_STATE)
	pciehp_green_led_on(p_slot);
	else
	pciehp_green_led_off(p_slot);
	pciehp_set_attention_status(p_slot, 0);
	ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
	slot_name(p_slot));
	p_slot->state = STATIC_STATE;
	break;
	case POWEROFF_STATE:
	case POWERON_STATE:
	/*
	* Ignore if the slot is on power-on or power-off state;
	* this means that the previous attention button action
	* to hot-add or hot-remove is undergoing
	*/
	ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
	break;
	default:
	ctrl_warn(ctrl, "ignoring invalid state %#x\n", p_slot->state);
	break;
	}
	}

	/*
	* Note: This function must be called with slot->lock held
	*/
	static void handle_surprise_event(struct slot *p_slot)
	{
	u8 getstatus;

	pciehp_get_adapter_status(p_slot, &getstatus);
	if (!getstatus)
	pciehp_queue_power_work(p_slot, DISABLE_REQ);
	else
	pciehp_queue_power_work(p_slot, ENABLE_REQ);
	}

	/*
	* Note: This function must be called with slot->lock held
	*/
	static void handle_link_event(struct slot *p_slot, u32 event)
	{
	struct controller *ctrl = p_slot->ctrl;

	switch (p_slot->state) {
	case BLINKINGON_STATE:
	case BLINKINGOFF_STATE:
	cancel_delayed_work(&p_slot->work);
	/* Fall through */
	case STATIC_STATE:
	pciehp_queue_power_work(p_slot, event == INT_LINK_UP ?
	ENABLE_REQ : DISABLE_REQ);
	break;
	case POWERON_STATE:
	if (event == INT_LINK_UP) {
	ctrl_info(ctrl,
	"Link Up event ignored on slot(%s): already powering on\n",
	slot_name(p_slot));
	} else {
	ctrl_info(ctrl,
	"Link Down event queued on slot(%s): currently getting powered on\n",
	slot_name(p_slot));
	pciehp_queue_power_work(p_slot, DISABLE_REQ);
	}
	break;
	case POWEROFF_STATE:
	if (event == INT_LINK_UP) {
	ctrl_info(ctrl,
	"Link Up event queued on slot(%s): currently getting powered off\n",
	slot_name(p_slot));
	pciehp_queue_power_work(p_slot, ENABLE_REQ);
	} else {
	ctrl_info(ctrl,
	"Link Down event ignored on slot(%s): already powering off\n",
	slot_name(p_slot));
	}
	break;
	default:
	ctrl_err(ctrl, "ignoring invalid state %#x on slot(%s)\n",
	p_slot->state, slot_name(p_slot));
	break;
	}
	}

	static void interrupt_event_handler(struct work_struct *work)
	{
	struct event_info *info = container_of(work, struct event_info, work);
	struct slot *p_slot = info->p_slot;
	struct controller *ctrl = p_slot->ctrl;

	mutex_lock(&p_slot->lock);
	switch (info->event_type) {
	case INT_BUTTON_PRESS:
	handle_button_press_event(p_slot);
	break;
	case INT_POWER_FAULT:
	if (!POWER_CTRL(ctrl))
	break;
	pciehp_set_attention_status(p_slot, 1);
	pciehp_green_led_off(p_slot);
	break;
	case INT_PRESENCE_ON:
	handle_surprise_event(p_slot);
	break;
	case INT_PRESENCE_OFF:
	/*
	* Regardless of surprise capability, we need to
	* definitely remove a card that has been pulled out!
	*/
	handle_surprise_event(p_slot);
	break;
	case INT_LINK_UP:
	case INT_LINK_DOWN:
	handle_link_event(p_slot, info->event_type);
	break;
	default:
	break;
	}
	mutex_unlock(&p_slot->lock);

	kfree(info);
	}

	/*
	* Note: This function must be called with slot->hotplug_lock held
	*/
	int pciehp_enable_slot(struct slot *p_slot)
	{
	u8 getstatus = 0;
	int rc;
	struct controller *ctrl = p_slot->ctrl;

	pciehp_get_adapter_status(p_slot, &getstatus);
	if (!getstatus) {
	ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
	return -ENODEV;
	}
	if (MRL_SENS(p_slot->ctrl)) {
	pciehp_get_latch_status(p_slot, &getstatus);
	if (getstatus) {
	ctrl_info(ctrl, "Latch open on slot(%s)\n",
	slot_name(p_slot));
	return -ENODEV;
	}
	}

	if (POWER_CTRL(p_slot->ctrl)) {
	pciehp_get_power_status(p_slot, &getstatus);
	if (getstatus) {
	ctrl_info(ctrl, "Already enabled on slot(%s)\n",
	slot_name(p_slot));
	return -EINVAL;
	}
	}

	pciehp_get_latch_status(p_slot, &getstatus);

	rc = board_added(p_slot);
	if (rc)
	pciehp_get_latch_status(p_slot, &getstatus);

	return rc;
	}

	/*
	* Note: This function must be called with slot->hotplug_lock held
	*/
	int pciehp_disable_slot(struct slot *p_slot)
	{
	u8 getstatus = 0;
	struct controller *ctrl = p_slot->ctrl;

	if (!p_slot->ctrl)
	return 1;

	if (POWER_CTRL(p_slot->ctrl)) {
	pciehp_get_power_status(p_slot, &getstatus);
	if (!getstatus) {
	ctrl_info(ctrl, "Already disabled on slot(%s)\n",
	slot_name(p_slot));
	return -EINVAL;
	}
	}

	return remove_board(p_slot);
	}

	int pciehp_sysfs_enable_slot(struct slot *p_slot)
	{
	int retval = -ENODEV;
	struct controller *ctrl = p_slot->ctrl;

	mutex_lock(&p_slot->lock);
	switch (p_slot->state) {
	case BLINKINGON_STATE:
	cancel_delayed_work(&p_slot->work);
	case STATIC_STATE:
	p_slot->state = POWERON_STATE;
	mutex_unlock(&p_slot->lock);
	mutex_lock(&p_slot->hotplug_lock);
	retval = pciehp_enable_slot(p_slot);
	mutex_unlock(&p_slot->hotplug_lock);
	mutex_lock(&p_slot->lock);
	p_slot->state = STATIC_STATE;
	break;
	case POWERON_STATE:
	ctrl_info(ctrl, "Slot %s is already in powering on state\n",
	slot_name(p_slot));
	break;
	case BLINKINGOFF_STATE:
	case POWEROFF_STATE:
	ctrl_info(ctrl, "Already enabled on slot %s\n",
	slot_name(p_slot));
	break;
	default:
	ctrl_err(ctrl, "invalid state %#x on slot %s\n",
	p_slot->state, slot_name(p_slot));
	break;
	}
	mutex_unlock(&p_slot->lock);

	return retval;
	}

	int pciehp_sysfs_disable_slot(struct slot *p_slot)
	{
	int retval = -ENODEV;
	struct controller *ctrl = p_slot->ctrl;

	mutex_lock(&p_slot->lock);
	switch (p_slot->state) {
	case BLINKINGOFF_STATE:
	cancel_delayed_work(&p_slot->work);
	case STATIC_STATE:
	p_slot->state = POWEROFF_STATE;
	mutex_unlock(&p_slot->lock);
	retval = pciehp_disable_slot(p_slot);
	mutex_lock(&p_slot->lock);
	p_slot->state = STATIC_STATE;
	break;
	case POWEROFF_STATE:
	ctrl_info(ctrl, "Slot %s is already in powering off state\n",
	slot_name(p_slot));
	break;
	case BLINKINGON_STATE:
	case POWERON_STATE:
	ctrl_info(ctrl, "Already disabled on slot %s\n",
	slot_name(p_slot));
	break;
	default:
	ctrl_err(ctrl, "invalid state %#x on slot %s\n",
	p_slot->state, slot_name(p_slot));
	break;
	}
	mutex_unlock(&p_slot->lock);

	return retval;
	}