1 files changed, 287 insertions, 521 deletions

diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c
index 643252d9bf3..4e6381481c5 100644
--- a/drivers/pci/hotplug/shpchp_ctrl.c
+++ b/drivers/pci/hotplug/shpchp_ctrl.c
@@ -32,65 +32,50 @@
 #include <linux/types.h>
 #include <linux/smp_lock.h>
 #include <linux/pci.h>
+#include <linux/workqueue.h>
 #include "../pci.h"
 #include "shpchp.h"
 
-static void interrupt_event_handler(struct controller *ctrl);
+static void interrupt_event_handler(void *data);
+static int shpchp_enable_slot(struct slot *p_slot);
+static int shpchp_disable_slot(struct slot *p_slot);
 
-static struct semaphore event_semaphore;	/* mutex for process loop (up if something to process) */
-static struct semaphore event_exit;		/* guard ensure thread has exited before calling it quits */
-static int event_finished;
-static unsigned long pushbutton_pending;	/* = 0 */
+static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
+{
+	struct event_info *info;
+
+	info = kmalloc(sizeof(*info), GFP_ATOMIC);
+	if (!info)
+		return -ENOMEM;
+
+	info->event_type = event_type;
+	info->p_slot = p_slot;
+	INIT_WORK(&info->work, interrupt_event_handler, info);
+
+	schedule_work(&info->work);
+
+	return 0;
+}
 
 u8 shpchp_handle_attention_button(u8 hp_slot, void *inst_id)
 {
 	struct controller *ctrl = (struct controller *) inst_id;
 	struct slot *p_slot;
-	u8 rc = 0;
-	u8 getstatus;
-	struct event_info *taskInfo;
+	u32 event_type;
 
 	/* Attention Button Change */
 	dbg("shpchp:  Attention button interrupt received.\n");
 	
-	/* This is the structure that tells the worker thread what to do */
-	taskInfo = &(ctrl->event_queue[ctrl->next_event]);
 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
-
 	p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
-	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
-	
-	ctrl->next_event = (ctrl->next_event + 1) % 10;
-	taskInfo->hp_slot = hp_slot;
-
-	rc++;
 
 	/*
 	 *  Button pressed - See if need to TAKE ACTION!!!
 	 */
 	info("Button pressed on Slot(%d)\n", ctrl->first_slot + hp_slot);
-	taskInfo->event_type = INT_BUTTON_PRESS;
-
-	if ((p_slot->state == BLINKINGON_STATE)
-	    || (p_slot->state == BLINKINGOFF_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
-		 */
-		taskInfo->event_type = INT_BUTTON_CANCEL;
-		info("Button cancel on Slot(%d)\n", ctrl->first_slot + hp_slot);
-	} else if ((p_slot->state == POWERON_STATE)
-		   || (p_slot->state == POWEROFF_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
-		 */
-		taskInfo->event_type = INT_BUTTON_IGNORE;
-		info("Button ignore on Slot(%d)\n", ctrl->first_slot + hp_slot);
-	}
+	event_type = INT_BUTTON_PRESS;
 
-	if (rc)
-		up(&event_semaphore);	/* signal event thread that new event is posted */
+	queue_interrupt_event(p_slot, event_type);
 
 	return 0;
 
@@ -100,21 +85,12 @@ u8 shpchp_handle_switch_change(u8 hp_slot, void *inst_id)
 {
 	struct controller *ctrl = (struct controller *) inst_id;
 	struct slot *p_slot;
-	u8 rc = 0;
 	u8 getstatus;
-	struct event_info *taskInfo;
+	u32 event_type;
 
 	/* Switch Change */
 	dbg("shpchp:  Switch interrupt received.\n");
 
-	/* 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++;
 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 	p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
@@ -126,9 +102,9 @@ u8 shpchp_handle_switch_change(u8 hp_slot, void *inst_id)
 		 * Switch opened
 		 */
 		info("Latch open on Slot(%d)\n", ctrl->first_slot + hp_slot);
-		taskInfo->event_type = INT_SWITCH_OPEN;
+		event_type = INT_SWITCH_OPEN;
 		if (p_slot->pwr_save && p_slot->presence_save) {
-			taskInfo->event_type = INT_POWER_FAULT;
+			event_type = INT_POWER_FAULT;
 			err("Surprise Removal of card\n");
 		}
 	} else {
@@ -136,34 +112,23 @@ u8 shpchp_handle_switch_change(u8 hp_slot, void *inst_id)
 		 *  Switch closed
 		 */
 		info("Latch close on Slot(%d)\n", ctrl->first_slot + hp_slot);
-		taskInfo->event_type = INT_SWITCH_CLOSE;
+		event_type = INT_SWITCH_CLOSE;
 	}
 
-	if (rc)
-		up(&event_semaphore);	/* signal event thread that new event is posted */
+	queue_interrupt_event(p_slot, event_type);
 
-	return rc;
+	return 1;
 }
 
 u8 shpchp_handle_presence_change(u8 hp_slot, void *inst_id)
 {
 	struct controller *ctrl = (struct controller *) inst_id;
 	struct slot *p_slot;
-	u8 rc = 0;
-	/*u8 temp_byte;*/
-	struct event_info *taskInfo;
+	u32 event_type;
 
 	/* Presence Change */
 	dbg("shpchp:  Presence/Notify input change.\n");
 
-	/* 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++;
 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 
 	/* 
@@ -175,39 +140,29 @@ u8 shpchp_handle_presence_change(u8 hp_slot, void *inst_id)
 		 * Card Present
 		 */
 		info("Card present on Slot(%d)\n", ctrl->first_slot + hp_slot);
-		taskInfo->event_type = INT_PRESENCE_ON;
+		event_type = INT_PRESENCE_ON;
 	} else {
 		/*
 		 * Not Present
 		 */
 		info("Card not present on Slot(%d)\n", ctrl->first_slot + hp_slot);
-		taskInfo->event_type = INT_PRESENCE_OFF;
+		event_type = INT_PRESENCE_OFF;
 	}
 
-	if (rc)
-		up(&event_semaphore);	/* signal event thread that new event is posted */
+	queue_interrupt_event(p_slot, event_type);
 
-	return rc;
+	return 1;
 }
 
 u8 shpchp_handle_power_fault(u8 hp_slot, void *inst_id)
 {
 	struct controller *ctrl = (struct controller *) inst_id;
 	struct slot *p_slot;
-	u8 rc = 0;
-	struct event_info *taskInfo;
+	u32 event_type;
 
 	/* Power fault */
 	dbg("shpchp:  Power fault interrupt received.\n");
 
-	/* 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++;
 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 
 	if ( !(p_slot->hpc_ops->query_power_fault(p_slot))) {
@@ -216,21 +171,21 @@ u8 shpchp_handle_power_fault(u8 hp_slot, void *inst_id)
 		 */
 		info("Power fault cleared on Slot(%d)\n", ctrl->first_slot + hp_slot);
 		p_slot->status = 0x00;
-		taskInfo->event_type = INT_POWER_FAULT_CLEAR;
+		event_type = INT_POWER_FAULT_CLEAR;
 	} else {
 		/*
 		 *   Power fault
 		 */
 		info("Power fault on Slot(%d)\n", ctrl->first_slot + hp_slot);
-		taskInfo->event_type = INT_POWER_FAULT;
+		event_type = INT_POWER_FAULT;
 		/* set power fault status for this board */
 		p_slot->status = 0xFF;
 		info("power fault bit %x set\n", hp_slot);
 	}
-	if (rc)
-		up(&event_semaphore);	/* signal event thread that new event is posted */
 
-	return rc;
+	queue_interrupt_event(p_slot, event_type);
+
+	return 1;
 }
 
 /* The following routines constitute the bulk of the 
@@ -242,21 +197,11 @@ static int change_bus_speed(struct controller *ctrl, struct slot *p_slot,
 	int rc = 0;
 
 	dbg("%s: change to speed %d\n", __FUNCTION__, speed);
-	down(&ctrl->crit_sect);
 	if ((rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, speed))) {
-		err("%s: Issue of set bus speed mode command failed\n", __FUNCTION__);
-		up(&ctrl->crit_sect);
+		err("%s: Issue of set bus speed mode command failed\n",
+		    __FUNCTION__);
 		return WRONG_BUS_FREQUENCY;
 	}
-		
-	if ((rc = p_slot->hpc_ops->check_cmd_status(ctrl))) {
-		err("%s: Can't set bus speed/mode in the case of adapter & bus mismatch\n",
-			  __FUNCTION__);
-		err("%s: Error code (%d)\n", __FUNCTION__, rc);
-		up(&ctrl->crit_sect);
-		return WRONG_BUS_FREQUENCY;
-	}
-	up(&ctrl->crit_sect);
 	return rc;
 }
 
@@ -265,33 +210,26 @@ static int fix_bus_speed(struct controller *ctrl, struct slot *pslot,
 		enum pci_bus_speed msp)
 { 
 	int rc = 0;
-	
-	if (flag != 0) { /* Other slots on the same bus are occupied */
-		if ( asp < bsp ) {
-			err("%s: speed of bus %x and adapter %x mismatch\n", __FUNCTION__, bsp, asp);
-			return WRONG_BUS_FREQUENCY;
+
+	/*
+	 * If other slots on the same bus are occupied, we cannot
+	 * change the bus speed.
+	 */
+	if (flag) {
+		if (asp < bsp) {
+			err("%s: speed of bus %x and adapter %x mismatch\n",
+			    __FUNCTION__, bsp, asp);
+			rc = WRONG_BUS_FREQUENCY;
 		}
+		return rc;
+	}
+
+	if (asp < msp) {
+		if (bsp != asp)
+			rc = change_bus_speed(ctrl, pslot, asp);
 	} else {
-		/* Other slots on the same bus are empty */
-		if (msp == bsp) {
-		/* if adapter_speed >= bus_speed, do nothing */
-			if (asp < bsp) {
-				/* 
-				* Try to lower bus speed to accommodate the adapter if other slots 
-				* on the same controller are empty
-				*/
-				if ((rc = change_bus_speed(ctrl, pslot, asp)))
-					return rc;
-			} 
-		} else {
-			if (asp < msp) {
-				if ((rc = change_bus_speed(ctrl, pslot, asp)))
-					return rc;
-			} else {
-				if ((rc = change_bus_speed(ctrl, pslot, msp)))
-					return rc;
-			}
-		}
+		if (bsp != msp)
+			rc = change_bus_speed(ctrl, pslot, msp);
 	}
 	return rc;
 }
@@ -308,8 +246,7 @@ static int board_added(struct slot *p_slot)
 	u8 hp_slot;
 	u8 slots_not_empty = 0;
 	int rc = 0;
-	enum pci_bus_speed adapter_speed, bus_speed, max_bus_speed;
-	u8 pi, mode;
+	enum pci_bus_speed asp, bsp, msp;
 	struct controller *ctrl = p_slot->ctrl;
 
 	hp_slot = p_slot->device - ctrl->slot_device_offset;
@@ -318,187 +255,68 @@ static int board_added(struct slot *p_slot)
 			__FUNCTION__, p_slot->device,
 			ctrl->slot_device_offset, hp_slot);
 
-	/* Wait for exclusive access to hardware */
-	down(&ctrl->crit_sect);
-
 	/* Power on slot without connecting to bus */
 	rc = p_slot->hpc_ops->power_on_slot(p_slot);
 	if (rc) {
 		err("%s: Failed to power on slot\n", __FUNCTION__);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
 		return -1;
 	}
 	
-	rc = p_slot->hpc_ops->check_cmd_status(ctrl);
-	if (rc) {
-		err("%s: Failed to power on slot, error code(%d)\n", __FUNCTION__, rc);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
-		return -1;
-	}
-
-	
 	if ((ctrl->pci_dev->vendor == 0x8086) && (ctrl->pci_dev->device == 0x0332)) {
 		if (slots_not_empty)
 			return WRONG_BUS_FREQUENCY;
 		
 		if ((rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, PCI_SPEED_33MHz))) {
 			err("%s: Issue of set bus speed mode command failed\n", __FUNCTION__);
-			up(&ctrl->crit_sect);
 			return WRONG_BUS_FREQUENCY;
 		}
 		
-		if ((rc = p_slot->hpc_ops->check_cmd_status(ctrl))) {
-			err("%s: Can't set bus speed/mode in the case of adapter & bus mismatch\n",
-				  __FUNCTION__);
-			err("%s: Error code (%d)\n", __FUNCTION__, rc);
-			up(&ctrl->crit_sect);
-			return WRONG_BUS_FREQUENCY;
-		}
 		/* turn on board, blink green LED, turn off Amber LED */
 		if ((rc = p_slot->hpc_ops->slot_enable(p_slot))) {
 			err("%s: Issue of Slot Enable command failed\n", __FUNCTION__);
-			up(&ctrl->crit_sect);
 			return rc;
 		}
-
-		if ((rc = p_slot->hpc_ops->check_cmd_status(ctrl))) {
-			err("%s: Failed to enable slot, error code(%d)\n", __FUNCTION__, rc);
-			up(&ctrl->crit_sect);
-			return rc;  
-		}
 	}
  
-	rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &adapter_speed);
-	/* 0 = PCI 33Mhz, 1 = PCI 66 Mhz, 2 = PCI-X 66 PA, 4 = PCI-X 66 ECC, */
-	/* 5 = PCI-X 133 PA, 7 = PCI-X 133 ECC,  0xa = PCI-X 133 Mhz 266, */
-	/* 0xd = PCI-X 133 Mhz 533 */
-	/* This encoding is different from the one used in cur_bus_speed & */
-	/* max_bus_speed */
-
-	if (rc  || adapter_speed == PCI_SPEED_UNKNOWN) {
-		err("%s: Can't get adapter speed or bus mode mismatch\n", __FUNCTION__);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
+	rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &asp);
+	if (rc) {
+		err("%s: Can't get adapter speed or bus mode mismatch\n",
+		    __FUNCTION__);
 		return WRONG_BUS_FREQUENCY;
 	}
 
-	rc = p_slot->hpc_ops->get_cur_bus_speed(p_slot, &bus_speed);
-	if (rc || bus_speed == PCI_SPEED_UNKNOWN) {
+	rc = p_slot->hpc_ops->get_cur_bus_speed(p_slot, &bsp);
+	if (rc) {
 		err("%s: Can't get bus operation speed\n", __FUNCTION__);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
 		return WRONG_BUS_FREQUENCY;
 	}
 
-	rc = p_slot->hpc_ops->get_max_bus_speed(p_slot, &max_bus_speed);
-	if (rc || max_bus_speed == PCI_SPEED_UNKNOWN) {
+	rc = p_slot->hpc_ops->get_max_bus_speed(p_slot, &msp);
+	if (rc) {
 		err("%s: Can't get max bus operation speed\n", __FUNCTION__);
-		max_bus_speed = bus_speed;
-	}
-
-	/* Done with exclusive hardware access */
-	up(&ctrl->crit_sect);
-
-	if ((rc  = p_slot->hpc_ops->get_prog_int(p_slot, &pi))) {
-		err("%s: Can't get controller programming interface, set it to 1\n", __FUNCTION__);
-		pi = 1;
+		msp = bsp;
 	}
 
 	/* Check if there are other slots or devices on the same bus */
 	if (!list_empty(&ctrl->pci_dev->subordinate->devices))
 		slots_not_empty = 1;
 
-	dbg("%s: slots_not_empty %d, pi %d\n", __FUNCTION__, 
-		slots_not_empty, pi);
-	dbg("adapter_speed %d, bus_speed %d, max_bus_speed %d\n", 
-		adapter_speed, bus_speed, max_bus_speed);
-
-	if (pi == 2) {
-		dbg("%s: In PI = %d\n", __FUNCTION__, pi);
-		if ((rc = p_slot->hpc_ops->get_mode1_ECC_cap(p_slot, &mode))) {
-			err("%s: Can't get Mode1_ECC, set mode to 0\n", __FUNCTION__);
-			mode = 0;
-		}
+	dbg("%s: slots_not_empty %d, adapter_speed %d, bus_speed %d, "
+	    "max_bus_speed %d\n", __FUNCTION__, slots_not_empty, asp,
+	    bsp, msp);
 
-		switch (adapter_speed) {
-		case PCI_SPEED_133MHz_PCIX_533:
-		case PCI_SPEED_133MHz_PCIX_266:
-			if ((bus_speed != adapter_speed) &&
-			   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-				return rc;
-			break;	
-		case PCI_SPEED_133MHz_PCIX_ECC:
-		case PCI_SPEED_133MHz_PCIX:
-			if (mode) { /* Bus - Mode 1 ECC */
-				if ((bus_speed != 0x7) &&
-				   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-					return rc;
-			} else {
-				if ((bus_speed != 0x4) &&
-				   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-					return rc;
-			}
-			break;
-		case PCI_SPEED_66MHz_PCIX_ECC:
-		case PCI_SPEED_66MHz_PCIX:
-			if (mode) { /* Bus - Mode 1 ECC */
-				if ((bus_speed != 0x5) &&
-				   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-					return rc;
-			} else {
-				if ((bus_speed != 0x2) &&
-				   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-					return rc;
-			}
-			break;
-		case PCI_SPEED_66MHz:
-			if ((bus_speed != 0x1) &&
-			   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed)))) 
-				return rc;
-			break;	
-		case PCI_SPEED_33MHz:
-			if (bus_speed > 0x0) {
-				if (slots_not_empty == 0) {
-					if ((rc = change_bus_speed(ctrl, p_slot, adapter_speed)))
-						return rc;
-				} else {
-					err("%s: speed of bus %x and adapter %x mismatch\n", __FUNCTION__, bus_speed, adapter_speed);
-					return WRONG_BUS_FREQUENCY;
-				}
-			}
-			break;
-		default:
-			err("%s: speed of bus %x and adapter %x mismatch\n", __FUNCTION__, bus_speed, adapter_speed);
-			return WRONG_BUS_FREQUENCY;
-		}
-	} else {
-		/* If adpater_speed == bus_speed, nothing to do here */
-		dbg("%s: In PI = %d\n", __FUNCTION__, pi);
-		if ((adapter_speed != bus_speed) &&
-		   ((rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, adapter_speed, bus_speed, max_bus_speed))))
-				return rc;
-	}
+	rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, asp, bsp, msp);
+	if (rc)
+		return rc;
 
-	down(&ctrl->crit_sect);
 	/* turn on board, blink green LED, turn off Amber LED */
 	if ((rc = p_slot->hpc_ops->slot_enable(p_slot))) {
 		err("%s: Issue of Slot Enable command failed\n", __FUNCTION__);
-		up(&ctrl->crit_sect);
 		return rc;
 	}
 
-	if ((rc = p_slot->hpc_ops->check_cmd_status(ctrl))) {
-		err("%s: Failed to enable slot, error code(%d)\n", __FUNCTION__, rc);
-		up(&ctrl->crit_sect);
-		return rc;  
-	}
-
-	up(&ctrl->crit_sect);
-
 	/* Wait for ~1 second */
-	wait_for_ctrl_irq (ctrl);
+	msleep(1000);
 
 	dbg("%s: slot status = %x\n", __FUNCTION__, p_slot->status);
 	/* Check for a power fault */
@@ -520,40 +338,18 @@ static int board_added(struct slot *p_slot)
 	p_slot->is_a_board = 0x01;
 	p_slot->pwr_save = 1;
 
-	/* Wait for exclusive access to hardware */
-	down(&ctrl->crit_sect);
-
 	p_slot->hpc_ops->green_led_on(p_slot);
 
-	/* Done with exclusive hardware access */
-	up(&ctrl->crit_sect);
-
 	return 0;
 
 err_exit:
-	/* Wait for exclusive access to hardware */
-	down(&ctrl->crit_sect);
-
 	/* turn off slot, turn on Amber LED, turn off Green LED */
 	rc = p_slot->hpc_ops->slot_disable(p_slot);
 	if (rc) {
 		err("%s: Issue of Slot Disable command failed\n", __FUNCTION__);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
-		return rc;
-	}
-
-	rc = p_slot->hpc_ops->check_cmd_status(ctrl);
-	if (rc) {
-		err("%s: Failed to disable slot, error code(%d)\n", __FUNCTION__, rc);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
 		return rc;
 	}
 
-	/* Done with exclusive hardware access */
-	up(&ctrl->crit_sect);
-
 	return(rc);
 }
 
@@ -580,37 +376,19 @@ static int remove_board(struct slot *p_slot)
 	if (p_slot->is_a_board)
 		p_slot->status = 0x01;
 
-	/* Wait for exclusive access to hardware */
-	down(&ctrl->crit_sect);
-
 	/* turn off slot, turn on Amber LED, turn off Green LED */
 	rc = p_slot->hpc_ops->slot_disable(p_slot);
 	if (rc) {
 		err("%s: Issue of Slot Disable command failed\n", __FUNCTION__);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
 		return rc;
 	}
-
-	rc = p_slot->hpc_ops->check_cmd_status(ctrl);
-	if (rc) {
-		err("%s: Failed to disable slot, error code(%d)\n", __FUNCTION__, rc);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
-		return rc;  
-	}
 	
 	rc = p_slot->hpc_ops->set_attention_status(p_slot, 0);
 	if (rc) {
 		err("%s: Issue of Set Attention command failed\n", __FUNCTION__);
-		/* Done with exclusive hardware access */
-		up(&ctrl->crit_sect);
 		return rc;
 	}
 
-	/* Done with exclusive hardware access */
-	up(&ctrl->crit_sect);
-
 	p_slot->pwr_save = 0;
 	p_slot->is_a_board = 0;
 
@@ -618,13 +396,10 @@ static int remove_board(struct slot *p_slot)
 }
 
 
-static void pushbutton_helper_thread (unsigned long data)
-{
-	pushbutton_pending = data;
-
-	up(&event_semaphore);
-}
-
+struct pushbutton_work_info {
+	struct slot *p_slot;
+	struct work_struct work;
+};
 
 /**
  * shpchp_pushbutton_thread
@@ -633,96 +408,63 @@ static void pushbutton_helper_thread (unsigned long data)
  * Handles all pending events and exits.
  *
  */
-static void shpchp_pushbutton_thread (unsigned long slot)
+static void shpchp_pushbutton_thread(void *data)
 {
-	struct slot *p_slot = (struct slot *) slot;
-	u8 getstatus;
-	
-	pushbutton_pending = 0;
-
-	if (!p_slot) {
-		dbg("%s: Error! slot NULL\n", __FUNCTION__);
-		return;
-	}
-
-	p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
-	if (getstatus) {
-		p_slot->state = POWEROFF_STATE;
+	struct pushbutton_work_info *info = data;
+	struct slot *p_slot = info->p_slot;
 
+	mutex_lock(&p_slot->lock);
+	switch (p_slot->state) {
+	case POWEROFF_STATE:
+		mutex_unlock(&p_slot->lock);
 		shpchp_disable_slot(p_slot);
+		mutex_lock(&p_slot->lock);
 		p_slot->state = STATIC_STATE;
-	} else {
-		p_slot->state = POWERON_STATE;
-
-		if (shpchp_enable_slot(p_slot)) {
-			/* Wait for exclusive access to hardware */
-			down(&p_slot->ctrl->crit_sect);
-
+		break;
+	case POWERON_STATE:
+		mutex_unlock(&p_slot->lock);
+		if (shpchp_enable_slot(p_slot))
 			p_slot->hpc_ops->green_led_off(p_slot);
-
-			/* Done with exclusive hardware access */
-			up(&p_slot->ctrl->crit_sect);
-		}
+		mutex_lock(&p_slot->lock);
 		p_slot->state = STATIC_STATE;
+		break;
+	default:
+		break;
 	}
+	mutex_unlock(&p_slot->lock);
 
-	return;
-}
-
-
-/* this is the main worker thread */
-static int event_thread(void* data)
-{
-	struct controller *ctrl;
-	lock_kernel();
-	daemonize("shpchpd_event");
-	unlock_kernel();
-
-	while (1) {
-		dbg("!!!!event_thread sleeping\n");
-		down_interruptible (&event_semaphore);
-		dbg("event_thread woken finished = %d\n", event_finished);
-		if (event_finished || signal_pending(current))
-			break;
-		/* Do stuff here */
-		if (pushbutton_pending)
-			shpchp_pushbutton_thread(pushbutton_pending);
-		else
-			for (ctrl = shpchp_ctrl_list; ctrl; ctrl=ctrl->next)
-				interrupt_event_handler(ctrl);
-	}
-	dbg("event_thread signals exit\n");
-	up(&event_exit);
-	return 0;
+	kfree(info);
 }
 
-int shpchp_event_start_thread (void)
+void queue_pushbutton_work(void *data)
 {
-	int pid;
+	struct slot *p_slot = data;
+	struct pushbutton_work_info *info;
 
-	/* initialize our semaphores */
-	init_MUTEX_LOCKED(&event_exit);
-	event_finished=0;
-
-	init_MUTEX_LOCKED(&event_semaphore);
-	pid = kernel_thread(event_thread, NULL, 0);
-
-	if (pid < 0) {
-		err ("Can't start up our event thread\n");
-		return -1;
+	info = kmalloc(sizeof(*info), GFP_KERNEL);
+	if (!info) {
+		err("%s: Cannot allocate memory\n", __FUNCTION__);
+		return;
 	}
-	return 0;
-}
-
+	info->p_slot = p_slot;
+	INIT_WORK(&info->work, shpchp_pushbutton_thread, info);
 
-void shpchp_event_stop_thread (void)
-{
-	event_finished = 1;
-	up(&event_semaphore);
-	down(&event_exit);
+	mutex_lock(&p_slot->lock);
+	switch (p_slot->state) {
+	case BLINKINGOFF_STATE:
+		p_slot->state = POWEROFF_STATE;
+		break;
+	case BLINKINGON_STATE:
+		p_slot->state = POWERON_STATE;
+		break;
+	default:
+		goto out;
+	}
+	queue_work(shpchp_wq, &info->work);
+ out:
+	mutex_unlock(&p_slot->lock);
 }
 
-
 static int update_slot_info (struct slot *slot)
 {
 	struct hotplug_slot_info *info;
@@ -742,149 +484,110 @@ static int update_slot_info (struct slot *slot)
 	return result;
 }
 
-static void interrupt_event_handler(struct controller *ctrl)
+/*
+ * Note: This function must be called with slot->lock held
+ */
+static void handle_button_press_event(struct slot *p_slot)
 {
-	int loop = 0;
-	int change = 1;
-	u8 hp_slot;
 	u8 getstatus;
-	struct slot *p_slot;
 
-	while (change) {
-		change = 0;
-
-		for (loop = 0; loop < 10; loop++) {
-			if (ctrl->event_queue[loop].event_type != 0) {
-				dbg("%s:loop %x event_type %x\n", __FUNCTION__, loop, 
-					ctrl->event_queue[loop].event_type);
-				hp_slot = ctrl->event_queue[loop].hp_slot;
-
-				p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
-
-				if (ctrl->event_queue[loop].event_type == INT_BUTTON_CANCEL) {
-					dbg("%s: button cancel\n", __FUNCTION__);
-					del_timer(&p_slot->task_event);
-
-					switch (p_slot->state) {
-					case BLINKINGOFF_STATE:
-						/* Wait for exclusive access to hardware */
-						down(&ctrl->crit_sect);
-
-						p_slot->hpc_ops->green_led_on(p_slot);
-
-						p_slot->hpc_ops->set_attention_status(p_slot, 0);
-
-						/* Done with exclusive hardware access */
-						up(&ctrl->crit_sect);
-						break;
-					case BLINKINGON_STATE:
-						/* Wait for exclusive access to hardware */
-						down(&ctrl->crit_sect);
-
-						p_slot->hpc_ops->green_led_off(p_slot);
-
-						p_slot->hpc_ops->set_attention_status(p_slot, 0);
-
-						/* Done with exclusive hardware access */
-						up(&ctrl->crit_sect);
-
-						break;
-					default:
-						warn("Not a valid state\n");
-						return;
-					}
-					info(msg_button_cancel, p_slot->number);
-					p_slot->state = STATIC_STATE;
-				} else if (ctrl->event_queue[loop].event_type == INT_BUTTON_PRESS) {
-					/* Button Pressed (No action on 1st press...) */
-					dbg("%s: Button pressed\n", __FUNCTION__);
-
-					p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
-					if (getstatus) {
-						/* slot is on */
-						dbg("%s: slot is on\n", __FUNCTION__);
-						p_slot->state = BLINKINGOFF_STATE;
-						info(msg_button_off, p_slot->number);
-					} else {
-						/* slot is off */
-						dbg("%s: slot is off\n", __FUNCTION__);
-						p_slot->state = BLINKINGON_STATE;
-						info(msg_button_on, p_slot->number);
-					}
-
-					/* Wait for exclusive access to hardware */
-					down(&ctrl->crit_sect);
-
-					/* blink green LED and turn off amber */
-					p_slot->hpc_ops->green_led_blink(p_slot);
-					
-					p_slot->hpc_ops->set_attention_status(p_slot, 0);
-
-					/* Done with exclusive hardware access */
-					up(&ctrl->crit_sect);
-
-					init_timer(&p_slot->task_event);
-					p_slot->task_event.expires = jiffies + 5 * HZ;   /* 5 second delay */
-					p_slot->task_event.function = (void (*)(unsigned long)) pushbutton_helper_thread;
-					p_slot->task_event.data = (unsigned long) p_slot;
-
-					dbg("%s: add_timer p_slot = %p\n", __FUNCTION__,(void *) p_slot);
-					add_timer(&p_slot->task_event);
-				} else if (ctrl->event_queue[loop].event_type == INT_POWER_FAULT) {
-					/***********POWER FAULT********************/
-					dbg("%s: power fault\n", __FUNCTION__);
-					/* Wait for exclusive access to hardware */
-					down(&ctrl->crit_sect);
-
-					p_slot->hpc_ops->set_attention_status(p_slot, 1);
-					
-					p_slot->hpc_ops->green_led_off(p_slot);
-
-					/* Done with exclusive hardware access */
-					up(&ctrl->crit_sect);
-				} else {
-					/* refresh notification */
-					if (p_slot)
-						update_slot_info(p_slot);
-				}
-
-				ctrl->event_queue[loop].event_type = 0;
-
-				change = 1;
-			}
-		}		/* End of FOR loop */
+	switch (p_slot->state) {
+	case STATIC_STATE:
+		p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
+		if (getstatus) {
+			p_slot->state = BLINKINGOFF_STATE;
+			info(msg_button_off, p_slot->number);
+		} else {
+			p_slot->state = BLINKINGON_STATE;
+			info(msg_button_on, p_slot->number);
+		}
+		/* blink green LED and turn off amber */
+		p_slot->hpc_ops->green_led_blink(p_slot);
+		p_slot->hpc_ops->set_attention_status(p_slot, 0);
+
+		schedule_delayed_work(&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
+		 */
+		info("Button cancel on Slot(%s)\n", p_slot->name);
+		dbg("%s: button cancel\n", __FUNCTION__);
+		cancel_delayed_work(&p_slot->work);
+		if (p_slot->state == BLINKINGOFF_STATE)
+			p_slot->hpc_ops->green_led_on(p_slot);
+		else
+			p_slot->hpc_ops->green_led_off(p_slot);
+		p_slot->hpc_ops->set_attention_status(p_slot, 0);
+		info(msg_button_cancel, p_slot->number);
+		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
+		 */
+		info("Button ignore on Slot(%s)\n", p_slot->name);
+		update_slot_info(p_slot);
+		break;
+	default:
+		warn("Not a valid state\n");
+		break;
 	}
+}
+
+static void interrupt_event_handler(void *data)
+{
+	struct event_info *info = data;
+	struct slot *p_slot = info->p_slot;
+
+	mutex_lock(&p_slot->lock);
+	switch (info->event_type) {
+	case INT_BUTTON_PRESS:
+		handle_button_press_event(p_slot);
+		break;
+	case INT_POWER_FAULT:
+		dbg("%s: power fault\n", __FUNCTION__);
+		p_slot->hpc_ops->set_attention_status(p_slot, 1);
+		p_slot->hpc_ops->green_led_off(p_slot);
+		break;
+	default:
+		update_slot_info(p_slot);
+		break;
+	}
+	mutex_unlock(&p_slot->lock);
 
-	return;
+	kfree(info);
 }
 
 
-int shpchp_enable_slot (struct slot *p_slot)
+static int shpchp_enable_slot (struct slot *p_slot)
 {
 	u8 getstatus = 0;
-	int rc;
+	int rc, retval = -ENODEV;
 
 	/* Check to see if (latch closed, card present, power off) */
-	down(&p_slot->ctrl->crit_sect);
+	mutex_lock(&p_slot->ctrl->crit_sect);
 	rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
 	if (rc || !getstatus) {
 		info("%s: no adapter on slot(%x)\n", __FUNCTION__, p_slot->number);
-		up(&p_slot->ctrl->crit_sect);
-		return -ENODEV;
+		goto out;
 	}
 	rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
 	if (rc || getstatus) {
 		info("%s: latch open on slot(%x)\n", __FUNCTION__, p_slot->number);
-		up(&p_slot->ctrl->crit_sect);
-		return -ENODEV;
+		goto out;
 	}
 	rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
 	if (rc || getstatus) {
 		info("%s: already enabled on slot(%x)\n", __FUNCTION__, p_slot->number);
-		up(&p_slot->ctrl->crit_sect);
-		return -ENODEV;
+		goto out;
 	}
-	up(&p_slot->ctrl->crit_sect);
 
 	p_slot->is_a_board = 1;
 
@@ -899,56 +602,119 @@ int shpchp_enable_slot (struct slot *p_slot)
 	     && p_slot->ctrl->num_slots == 1) {
 		/* handle amd pogo errata; this must be done before enable  */
 		amd_pogo_errata_save_misc_reg(p_slot);
-		rc = board_added(p_slot);
+		retval = board_added(p_slot);
 		/* handle amd pogo errata; this must be done after enable  */
 		amd_pogo_errata_restore_misc_reg(p_slot);
 	} else
-		rc = board_added(p_slot);
+		retval = board_added(p_slot);
 
-	if (rc) {
+	if (retval) {
 		p_slot->hpc_ops->get_adapter_status(p_slot,
 				&(p_slot->presence_save));
 		p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
 	}
 
 	update_slot_info(p_slot);
-	return rc;
+ out:
+	mutex_unlock(&p_slot->ctrl->crit_sect);
+	return retval;
 }
 
 
-int shpchp_disable_slot (struct slot *p_slot)
+static int shpchp_disable_slot (struct slot *p_slot)
 {
 	u8 getstatus = 0;
-	int ret = 0;
+	int rc, retval = -ENODEV;
 
 	if (!p_slot->ctrl)
 		return -ENODEV;
 
 	/* Check to see if (latch closed, card present, power on) */
-	down(&p_slot->ctrl->crit_sect);
+	mutex_lock(&p_slot->ctrl->crit_sect);
 
-	ret = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
-	if (ret || !getstatus) {
+	rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
+	if (rc || !getstatus) {
 		info("%s: no adapter on slot(%x)\n", __FUNCTION__, p_slot->number);
-		up(&p_slot->ctrl->crit_sect);
-		return -ENODEV;
+		goto out;
 	}
-	ret = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
-	if (ret || getstatus) {
+	rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
+	if (rc || getstatus) {
 		info("%s: latch open on slot(%x)\n", __FUNCTION__, p_slot->number);
-		up(&p_slot->ctrl->crit_sect);
-		return -ENODEV;
+		goto out;
 	}
-	ret = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
-	if (ret || !getstatus) {
+	rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
+	if (rc || !getstatus) {
 		info("%s: already disabled slot(%x)\n", __FUNCTION__, p_slot->number);
-		up(&p_slot->ctrl->crit_sect);
-		return -ENODEV;
+		goto out;
 	}
-	up(&p_slot->ctrl->crit_sect);
 
-	ret = remove_board(p_slot);
+	retval = remove_board(p_slot);
 	update_slot_info(p_slot);
-	return ret;
+ out:
+	mutex_unlock(&p_slot->ctrl->crit_sect);
+	return retval;
 }
 
+int shpchp_sysfs_enable_slot(struct slot *p_slot)
+{
+	int retval = -ENODEV;
+
+	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);
+		retval = shpchp_enable_slot(p_slot);
+		mutex_lock(&p_slot->lock);
+		p_slot->state = STATIC_STATE;
+		break;
+	case POWERON_STATE:
+		info("Slot %s is already in powering on state\n",
+		     p_slot->name);
+		break;
+	case BLINKINGOFF_STATE:
+	case POWEROFF_STATE:
+		info("Already enabled on slot %s\n", p_slot->name);
+		break;
+	default:
+		err("Not a valid state on slot %s\n", p_slot->name);
+		break;
+	}
+	mutex_unlock(&p_slot->lock);
+
+	return retval;
+}
+
+int shpchp_sysfs_disable_slot(struct slot *p_slot)
+{
+	int retval = -ENODEV;
+
+	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 = shpchp_disable_slot(p_slot);
+		mutex_lock(&p_slot->lock);
+		p_slot->state = STATIC_STATE;
+		break;
+	case POWEROFF_STATE:
+		info("Slot %s is already in powering off state\n",
+		     p_slot->name);
+		break;
+	case BLINKINGON_STATE:
+	case POWERON_STATE:
+		info("Already disabled on slot %s\n", p_slot->name);
+		break;
+	default:
+		err("Not a valid state on slot %s\n", p_slot->name);
+		break;
+	}
+	mutex_unlock(&p_slot->lock);
+
+	return retval;
+}