drivers/staging/meilhaus/me8200_do.c - kernel/windcharger - Git at Google

 /**
  * @file me8200_do.c
  *
  * @brief ME-8200 digital output subdevice instance.
  * @note Copyright (C) 2007 Meilhaus Electronic GmbH (support@meilhaus.de)
  * @author Guenter Gebhardt
  * @author Krzysztof Gantzke	(k.gantzke@meilhaus.de)
  */

 /*
  * Copyright (C) 2007 Meilhaus Electronic GmbH (support@meilhaus.de)
  *
  * This file 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.  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.
  */

 #ifndef __KERNEL__
 #  define __KERNEL__
 #endif

 /*
  * Includes
  */
 #include <linux/module.h>

 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/types.h>

 #include "medefines.h"
 #include "meinternal.h"
 #include "meerror.h"

 #include "meids.h"
 #include "medebug.h"
 #include "me8200_reg.h"
 #include "me8200_do_reg.h"
 #include "me8200_do.h"

 /*
  * Defines
  */

 /*
  * Functions
  */

 static int me8200_do_io_irq_start(me_subdevice_t *subdevice,
 				  struct file *filep,
 				  int channel,
 				  int irq_source,
 				  int irq_edge, int irq_arg, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	int err = ME_ERRNO_SUCCESS;
 	uint8_t tmp;
 	unsigned long status;

 	if (flags & ~ME_IO_IRQ_START_DIO_BYTE) {
 		PERROR("Invalid flag specified.\n");
 		return ME_ERRNO_INVALID_FLAGS;
 	}

 	if (channel != 0) {
 		PERROR("Invalid channel specified.\n");
 		return ME_ERRNO_INVALID_CHANNEL;
 	}

 	if (irq_source != ME_IRQ_SOURCE_DIO_OVER_TEMP) {
 		PERROR("Invalid interrupt source specified.\n");
 		return ME_ERRNO_INVALID_IRQ_SOURCE;
 	}

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	ME_SUBDEVICE_ENTER;

 	spin_lock_irqsave(&instance->subdevice_lock, status);
 	spin_lock(instance->irq_mode_lock);
 	tmp = inb(instance->irq_ctrl_reg);
 	tmp |=
 	    ME8200_IRQ_MODE_BIT_ENABLE_POWER << (ME8200_IRQ_MODE_POWER_SHIFT *
 						 instance->do_idx);
 	outb(tmp, instance->irq_ctrl_reg);
 	PDEBUG_REG("irq_ctrl_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
 		   instance->irq_ctrl_reg - instance->reg_base, tmp);
 	spin_unlock(instance->irq_mode_lock);
 	instance->rised = 0;
 	spin_unlock_irqrestore(&instance->subdevice_lock, status);

 	ME_SUBDEVICE_EXIT;

 	return err;
 }

 static int me8200_do_io_irq_wait(me_subdevice_t *subdevice,
 				 struct file *filep,
 				 int channel,
 				 int *irq_count,
 				 int *value, int time_out, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	int err = ME_ERRNO_SUCCESS;
 	long t = 0;
 	unsigned long cpu_flags;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	if (flags) {
 		PERROR("Invalid flag specified.\n");
 		return ME_ERRNO_INVALID_FLAGS;
 	}

 	if (time_out < 0) {
 		PERROR("Invalid time_out specified.\n");
 		return ME_ERRNO_INVALID_TIMEOUT;
 	}

 	if (time_out) {
 		t = (time_out * HZ) / 1000;

 		if (t == 0)
 			t = 1;
 	}

 	ME_SUBDEVICE_ENTER;

 	if (instance->rised <= 0) {
 		instance->rised = 0;

 		if (time_out) {
 			t = wait_event_interruptible_timeout(instance->
 							     wait_queue,
 							     (instance->rised !=
 							      0), t);

 			if (t == 0) {
 				PERROR
 				    ("Wait on external interrupt timed out.\n");
 				err = ME_ERRNO_TIMEOUT;
 			}
 		} else {
 			wait_event_interruptible(instance->wait_queue,
 						 (instance->rised != 0));
 		}

 		if (instance->rised < 0) {
 			PERROR("Wait on interrupt aborted by user.\n");
 			err = ME_ERRNO_CANCELLED;
 		}
 	}

 	if (signal_pending(current)) {
 		PERROR("Wait on external interrupt aborted by signal.\n");
 		err = ME_ERRNO_SIGNAL;
 	}

 	spin_lock_irqsave(&instance->subdevice_lock, cpu_flags);
 	instance->rised = 0;
 	*irq_count = instance->count;
 	*value = 0;
 	spin_unlock_irqrestore(&instance->subdevice_lock, cpu_flags);

 	ME_SUBDEVICE_EXIT;

 	return err;
 }

 static int me8200_do_io_irq_stop(me_subdevice_t *subdevice,
 				 struct file *filep, int channel, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	uint8_t tmp;
 	unsigned long cpu_flags;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	if (flags) {
 		PERROR("Invalid flag specified.\n");
 		return ME_ERRNO_INVALID_FLAGS;
 	}

 	ME_SUBDEVICE_ENTER;

 	spin_lock_irqsave(&instance->subdevice_lock, cpu_flags);
 	spin_lock(instance->irq_mode_lock);
 	tmp = inb(instance->irq_ctrl_reg);
 	tmp &=
 	    ~(ME8200_IRQ_MODE_BIT_ENABLE_POWER <<
 	      (ME8200_IRQ_MODE_POWER_SHIFT * instance->do_idx));
 	outb(tmp, instance->irq_ctrl_reg);
 	PDEBUG_REG("irq_ctrl_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
 		   instance->irq_ctrl_reg - instance->reg_base, tmp);
 	spin_unlock(instance->irq_mode_lock);
 	instance->rised = -1;
 	spin_unlock_irqrestore(&instance->subdevice_lock, cpu_flags);
 	wake_up_interruptible_all(&instance->wait_queue);

 	ME_SUBDEVICE_EXIT;

 	return ME_ERRNO_SUCCESS;
 }

 static int me8200_do_io_reset_subdevice(struct me_subdevice *subdevice,
 					struct file *filep, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	unsigned long cpu_flags;
 	uint8_t tmp;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	if (flags) {
 		PERROR("Invalid flag specified.\n");
 		return ME_ERRNO_INVALID_FLAGS;
 	}

 	ME_SUBDEVICE_ENTER;

 	spin_lock_irqsave(&instance->subdevice_lock, cpu_flags);
 	outb(0x00, instance->port_reg);
 	PDEBUG_REG("port_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
 		   instance->port_reg - instance->reg_base, 0x00);
 	spin_lock(instance->irq_mode_lock);
 	tmp = inb(instance->irq_ctrl_reg);
 	tmp &=
 	    ~(ME8200_IRQ_MODE_BIT_ENABLE_POWER <<
 	      (ME8200_IRQ_MODE_POWER_SHIFT * instance->do_idx));
 	outb(tmp, instance->irq_ctrl_reg);
 	PDEBUG_REG("irq_ctrl_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
 		   instance->irq_ctrl_reg - instance->reg_base, tmp);
 	spin_unlock(instance->irq_mode_lock);
 	instance->rised = -1;
 	instance->count = 0;
 	spin_unlock_irqrestore(&instance->subdevice_lock, cpu_flags);
 	wake_up_interruptible_all(&instance->wait_queue);

 	ME_SUBDEVICE_EXIT;

 	return ME_ERRNO_SUCCESS;
 }

 static int me8200_do_io_single_config(me_subdevice_t *subdevice,
 				      struct file *filep,
 				      int channel,
 				      int single_config,
 				      int ref,
 				      int trig_chan,
 				      int trig_type, int trig_edge, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	int err = ME_ERRNO_SUCCESS;
 	unsigned long status;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	ME_SUBDEVICE_ENTER;

 	spin_lock_irqsave(&instance->subdevice_lock, status);
 	switch (flags) {
 	case ME_IO_SINGLE_CONFIG_NO_FLAGS:
 	case ME_IO_SINGLE_CONFIG_DIO_BYTE:
 		if (channel == 0) {
 			if (single_config == ME_SINGLE_CONFIG_DIO_OUTPUT) {
 			} else {
 				PERROR("Invalid byte direction specified.\n");
 				err = ME_ERRNO_INVALID_SINGLE_CONFIG;
 			}
 		} else {
 			PERROR("Invalid byte specified.\n");
 			err = ME_ERRNO_INVALID_CHANNEL;
 		}
 		break;

 	default:
 		PERROR("Invalid flags specified.\n");
 		err = ME_ERRNO_INVALID_FLAGS;
 	}
 	spin_unlock_irqrestore(&instance->subdevice_lock, status);

 	ME_SUBDEVICE_EXIT;

 	return err;
 }

 static int me8200_do_io_single_read(me_subdevice_t *subdevice,
 				    struct file *filep,
 				    int channel,
 				    int *value, int time_out, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	int err = ME_ERRNO_SUCCESS;
 	unsigned long status;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	ME_SUBDEVICE_ENTER;

 	spin_lock_irqsave(&instance->subdevice_lock, status);
 	switch (flags) {
 	case ME_IO_SINGLE_TYPE_DIO_BIT:
 		if ((channel >= 0) && (channel < 8)) {
 			*value = inb(instance->port_reg) & (0x1 << channel);
 		} else {
 			PERROR("Invalid bit number specified.\n");
 			err = ME_ERRNO_INVALID_CHANNEL;
 		}
 		break;

 	case ME_IO_SINGLE_NO_FLAGS:
 	case ME_IO_SINGLE_TYPE_DIO_BYTE:
 		if (channel == 0) {
 			*value = inb(instance->port_reg);
 		} else {
 			PERROR("Invalid byte number specified.\n");
 			err = ME_ERRNO_INVALID_CHANNEL;
 		}
 		break;

 	default:
 		PERROR("Invalid flags specified.\n");
 		err = ME_ERRNO_INVALID_FLAGS;
 	}
 	spin_unlock_irqrestore(&instance->subdevice_lock, status);

 	ME_SUBDEVICE_EXIT;

 	return err;
 }

 static int me8200_do_io_single_write(me_subdevice_t *subdevice,
 				     struct file *filep,
 				     int channel,
 				     int value, int time_out, int flags)
 {
 	me8200_do_subdevice_t *instance;
 	int err = ME_ERRNO_SUCCESS;
 	uint8_t state;
 	unsigned long status;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	ME_SUBDEVICE_ENTER;

 	spin_lock_irqsave(&instance->subdevice_lock, status);
 	switch (flags) {
 	case ME_IO_SINGLE_TYPE_DIO_BIT:
 		if ((channel >= 0) && (channel < 8)) {
 			state = inb(instance->port_reg);
 			state =
 			    value ? (state | (0x1 << channel)) : (state &
 								  ~(0x1 <<
 								    channel));
 			outb(state, instance->port_reg);
 			PDEBUG_REG("port_reg outb(0x%lX+0x%lX)=0x%x\n",
 				   instance->reg_base,
 				   instance->port_reg - instance->reg_base,
 				   state);
 		} else {
 			PERROR("Invalid bit number specified.\n");
 			err = ME_ERRNO_INVALID_CHANNEL;
 		}
 		break;

 	case ME_IO_SINGLE_NO_FLAGS:
 	case ME_IO_SINGLE_TYPE_DIO_BYTE:
 		if (channel == 0) {
 			outb(value, instance->port_reg);
 			PDEBUG_REG("port_reg outb(0x%lX+0x%lX)=0x%x\n",
 				   instance->reg_base,
 				   instance->port_reg - instance->reg_base,
 				   value);
 		} else {
 			PERROR("Invalid byte number specified.\n");
 			err = ME_ERRNO_INVALID_CHANNEL;
 		}
 		break;

 	default:
 		PERROR("Invalid flags specified.\n");
 		err = ME_ERRNO_INVALID_FLAGS;
 	}
 	spin_unlock_irqrestore(&instance->subdevice_lock, status);

 	ME_SUBDEVICE_EXIT;

 	return err;
 }

 static int me8200_do_query_number_channels(me_subdevice_t *subdevice,
 					   int *number)
 {
 	PDEBUG("executed.\n");
 	*number = 8;
 	return ME_ERRNO_SUCCESS;
 }

 static int me8200_do_query_subdevice_type(me_subdevice_t *subdevice,
 					  int *type, int *subtype)
 {
 	PDEBUG("executed.\n");
 	*type = ME_TYPE_DO;
 	*subtype = ME_SUBTYPE_SINGLE;
 	return ME_ERRNO_SUCCESS;
 }

 static int me8200_do_query_subdevice_caps(me_subdevice_t *subdevice, int *caps)
 {
 	PDEBUG("executed.\n");
 	*caps = ME_CAPS_DIO_OVER_TEMP_IRQ;
 	return ME_ERRNO_SUCCESS;
 }

 static void me8200_do_destructor(struct me_subdevice *subdevice)
 {
 	me8200_do_subdevice_t *instance;

 	PDEBUG("executed.\n");

 	instance = (me8200_do_subdevice_t *) subdevice;

 	free_irq(instance->irq, (void *)instance);
 	me_subdevice_deinit(&instance->base);
 	kfree(instance);
 }

 static irqreturn_t me8200_do_isr(int irq, void *dev_id)
 {
 	me8200_do_subdevice_t *instance;
 	uint16_t ctrl;
 	uint8_t irq_status;

 	instance = (me8200_do_subdevice_t *) dev_id;

 	if (irq != instance->irq) {
 		PERROR("Incorrect interrupt num: %d.\n", irq);
 		return IRQ_NONE;
 	}

 	irq_status = inb(instance->irq_status_reg);
 	if (!
 	    (irq_status &
 	     (ME8200_DO_IRQ_STATUS_BIT_ACTIVE << instance->do_idx))) {
 		PINFO
 		    ("%ld Shared interrupt. %s(): idx=%d irq_status_reg=0x%04X\n",
 		     jiffies, __func__, instance->do_idx, irq_status);
 		return IRQ_NONE;
 	}

 	PDEBUG("executed.\n");

 	spin_lock(&instance->subdevice_lock);
 	instance->rised = 1;
 	instance->count++;

 	spin_lock(instance->irq_mode_lock);
 	ctrl = inw(instance->irq_ctrl_reg);
 	ctrl |= ME8200_IRQ_MODE_BIT_CLEAR_POWER << instance->do_idx;
 	outw(ctrl, instance->irq_ctrl_reg);
 	PDEBUG_REG("irq_ctrl_reg outw(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
 		   instance->irq_ctrl_reg - instance->reg_base, ctrl);
 	ctrl &= ~(ME8200_IRQ_MODE_BIT_CLEAR_POWER << instance->do_idx);
 	outw(ctrl, instance->irq_ctrl_reg);
 	PDEBUG_REG("irq_ctrl_reg outw(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
 		   instance->irq_ctrl_reg - instance->reg_base, ctrl);
 	spin_unlock(instance->irq_mode_lock);
 	spin_unlock(&instance->subdevice_lock);
 	wake_up_interruptible_all(&instance->wait_queue);

 	return IRQ_HANDLED;
 }

 me8200_do_subdevice_t *me8200_do_constructor(uint32_t reg_base,
 					     unsigned int do_idx,
 					     int irq,
 					     spinlock_t *irq_mode_lock)
 {
 	me8200_do_subdevice_t *subdevice;
 	int err;

 	PDEBUG("executed.\n");

 	/* Allocate memory for subdevice instance */
 	subdevice = kmalloc(sizeof(me8200_do_subdevice_t), GFP_KERNEL);

 	if (!subdevice) {
 		PERROR("Cannot get memory for subdevice instance.\n");
 		return NULL;
 	}

 	memset(subdevice, 0, sizeof(me8200_do_subdevice_t));

 	/* Initialize subdevice base class */
 	err = me_subdevice_init(&subdevice->base);

 	if (err) {
 		PERROR("Cannot initialize subdevice base class instance.\n");
 		kfree(subdevice);
 		return NULL;
 	}
 	// Initialize spin locks.
 	spin_lock_init(&subdevice->subdevice_lock);

 	subdevice->irq_mode_lock = irq_mode_lock;

 	/* Save the index of the digital output */
 	subdevice->do_idx = do_idx;
 	subdevice->irq = irq;

 	/* Initialize the registers */
 	if (do_idx == 0) {
 		subdevice->port_reg = reg_base + ME8200_DO_PORT_0_REG;
 	} else if (do_idx == 1) {
 		subdevice->port_reg = reg_base + ME8200_DO_PORT_1_REG;
 	} else {
 		PERROR("Wrong subdevice idx=%d.\n", do_idx);
 		kfree(subdevice);
 		return NULL;
 	}
 	subdevice->irq_ctrl_reg = reg_base + ME8200_IRQ_MODE_REG;
 	subdevice->irq_status_reg = reg_base + ME8200_DO_IRQ_STATUS_REG;
 #ifdef MEDEBUG_DEBUG_REG
 	subdevice->reg_base = reg_base;
 #endif

 	/* Initialize the wait queue */
 	init_waitqueue_head(&subdevice->wait_queue);

 	/* Request the interrupt line */
 	err = request_irq(irq, me8200_do_isr,
 			  IRQF_DISABLED | IRQF_SHARED,
 			  ME8200_NAME, (void *)subdevice);

 	if (err) {
 		PERROR("Cannot get interrupt line.\n");
 		kfree(subdevice);
 		return NULL;
 	}
 	PINFO("Registered irq=%d.\n", irq);

 	/* Overload base class methods. */
 	subdevice->base.me_subdevice_io_irq_start = me8200_do_io_irq_start;
 	subdevice->base.me_subdevice_io_irq_wait = me8200_do_io_irq_wait;
 	subdevice->base.me_subdevice_io_irq_stop = me8200_do_io_irq_stop;
 	subdevice->base.me_subdevice_io_reset_subdevice =
 	    me8200_do_io_reset_subdevice;
 	subdevice->base.me_subdevice_io_single_config =
 	    me8200_do_io_single_config;
 	subdevice->base.me_subdevice_io_single_read = me8200_do_io_single_read;
 	subdevice->base.me_subdevice_io_single_write =
 	    me8200_do_io_single_write;
 	subdevice->base.me_subdevice_query_number_channels =
 	    me8200_do_query_number_channels;
 	subdevice->base.me_subdevice_query_subdevice_type =
 	    me8200_do_query_subdevice_type;
 	subdevice->base.me_subdevice_query_subdevice_caps =
 	    me8200_do_query_subdevice_caps;
 	subdevice->base.me_subdevice_destructor = me8200_do_destructor;

 	subdevice->rised = 0;
 	subdevice->count = 0;

 	return subdevice;
 }
	/**
	* @file me8200_do.c
	*
	* @brief ME-8200 digital output subdevice instance.
	* @note Copyright (C) 2007 Meilhaus Electronic GmbH (support@meilhaus.de)
	* @author Guenter Gebhardt
	* @author Krzysztof Gantzke (k.gantzke@meilhaus.de)
	*/

	/*
	* Copyright (C) 2007 Meilhaus Electronic GmbH (support@meilhaus.de)
	*
	* This file 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. 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.
	*/

	#ifndef __KERNEL__
	# define __KERNEL__
	#endif

	/*
	* Includes
	*/
	#include <linux/module.h>

	#include <linux/slab.h>
	#include <linux/spinlock.h>
	#include <linux/interrupt.h>
	#include <linux/io.h>
	#include <linux/types.h>

	#include "medefines.h"
	#include "meinternal.h"
	#include "meerror.h"

	#include "meids.h"
	#include "medebug.h"
	#include "me8200_reg.h"
	#include "me8200_do_reg.h"
	#include "me8200_do.h"

	/*
	* Defines
	*/

	/*
	* Functions
	*/

	static int me8200_do_io_irq_start(me_subdevice_t *subdevice,
	struct file *filep,
	int channel,
	int irq_source,
	int irq_edge, int irq_arg, int flags)
	{
	me8200_do_subdevice_t *instance;
	int err = ME_ERRNO_SUCCESS;
	uint8_t tmp;
	unsigned long status;

	if (flags & ~ME_IO_IRQ_START_DIO_BYTE) {
	PERROR("Invalid flag specified.\n");
	return ME_ERRNO_INVALID_FLAGS;
	}

	if (channel != 0) {
	PERROR("Invalid channel specified.\n");
	return ME_ERRNO_INVALID_CHANNEL;
	}

	if (irq_source != ME_IRQ_SOURCE_DIO_OVER_TEMP) {
	PERROR("Invalid interrupt source specified.\n");
	return ME_ERRNO_INVALID_IRQ_SOURCE;
	}

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	ME_SUBDEVICE_ENTER;

	spin_lock_irqsave(&instance->subdevice_lock, status);
	spin_lock(instance->irq_mode_lock);
	tmp = inb(instance->irq_ctrl_reg);
	tmp \|=
	ME8200_IRQ_MODE_BIT_ENABLE_POWER << (ME8200_IRQ_MODE_POWER_SHIFT *
	instance->do_idx);
	outb(tmp, instance->irq_ctrl_reg);
	PDEBUG_REG("irq_ctrl_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
	instance->irq_ctrl_reg - instance->reg_base, tmp);
	spin_unlock(instance->irq_mode_lock);
	instance->rised = 0;
	spin_unlock_irqrestore(&instance->subdevice_lock, status);

	ME_SUBDEVICE_EXIT;

	return err;
	}

	static int me8200_do_io_irq_wait(me_subdevice_t *subdevice,
	struct file *filep,
	int channel,
	int *irq_count,
	int *value, int time_out, int flags)
	{
	me8200_do_subdevice_t *instance;
	int err = ME_ERRNO_SUCCESS;
	long t = 0;
	unsigned long cpu_flags;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	if (flags) {
	PERROR("Invalid flag specified.\n");
	return ME_ERRNO_INVALID_FLAGS;
	}

	if (time_out < 0) {
	PERROR("Invalid time_out specified.\n");
	return ME_ERRNO_INVALID_TIMEOUT;
	}

	if (time_out) {
	t = (time_out * HZ) / 1000;

	if (t == 0)
	t = 1;
	}

	ME_SUBDEVICE_ENTER;

	if (instance->rised <= 0) {
	instance->rised = 0;

	if (time_out) {
	t = wait_event_interruptible_timeout(instance->
	wait_queue,
	(instance->rised !=
	0), t);

	if (t == 0) {
	PERROR
	("Wait on external interrupt timed out.\n");
	err = ME_ERRNO_TIMEOUT;
	}
	} else {
	wait_event_interruptible(instance->wait_queue,
	(instance->rised != 0));
	}

	if (instance->rised < 0) {
	PERROR("Wait on interrupt aborted by user.\n");
	err = ME_ERRNO_CANCELLED;
	}
	}

	if (signal_pending(current)) {
	PERROR("Wait on external interrupt aborted by signal.\n");
	err = ME_ERRNO_SIGNAL;
	}

	spin_lock_irqsave(&instance->subdevice_lock, cpu_flags);
	instance->rised = 0;
	*irq_count = instance->count;
	*value = 0;
	spin_unlock_irqrestore(&instance->subdevice_lock, cpu_flags);

	ME_SUBDEVICE_EXIT;

	return err;
	}

	static int me8200_do_io_irq_stop(me_subdevice_t *subdevice,
	struct file *filep, int channel, int flags)
	{
	me8200_do_subdevice_t *instance;
	uint8_t tmp;
	unsigned long cpu_flags;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	if (flags) {
	PERROR("Invalid flag specified.\n");
	return ME_ERRNO_INVALID_FLAGS;
	}

	ME_SUBDEVICE_ENTER;

	spin_lock_irqsave(&instance->subdevice_lock, cpu_flags);
	spin_lock(instance->irq_mode_lock);
	tmp = inb(instance->irq_ctrl_reg);
	tmp &=
	~(ME8200_IRQ_MODE_BIT_ENABLE_POWER <<
	(ME8200_IRQ_MODE_POWER_SHIFT * instance->do_idx));
	outb(tmp, instance->irq_ctrl_reg);
	PDEBUG_REG("irq_ctrl_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
	instance->irq_ctrl_reg - instance->reg_base, tmp);
	spin_unlock(instance->irq_mode_lock);
	instance->rised = -1;
	spin_unlock_irqrestore(&instance->subdevice_lock, cpu_flags);
	wake_up_interruptible_all(&instance->wait_queue);

	ME_SUBDEVICE_EXIT;

	return ME_ERRNO_SUCCESS;
	}

	static int me8200_do_io_reset_subdevice(struct me_subdevice *subdevice,
	struct file *filep, int flags)
	{
	me8200_do_subdevice_t *instance;
	unsigned long cpu_flags;
	uint8_t tmp;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	if (flags) {
	PERROR("Invalid flag specified.\n");
	return ME_ERRNO_INVALID_FLAGS;
	}

	ME_SUBDEVICE_ENTER;

	spin_lock_irqsave(&instance->subdevice_lock, cpu_flags);
	outb(0x00, instance->port_reg);
	PDEBUG_REG("port_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
	instance->port_reg - instance->reg_base, 0x00);
	spin_lock(instance->irq_mode_lock);
	tmp = inb(instance->irq_ctrl_reg);
	tmp &=
	~(ME8200_IRQ_MODE_BIT_ENABLE_POWER <<
	(ME8200_IRQ_MODE_POWER_SHIFT * instance->do_idx));
	outb(tmp, instance->irq_ctrl_reg);
	PDEBUG_REG("irq_ctrl_reg outb(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
	instance->irq_ctrl_reg - instance->reg_base, tmp);
	spin_unlock(instance->irq_mode_lock);
	instance->rised = -1;
	instance->count = 0;
	spin_unlock_irqrestore(&instance->subdevice_lock, cpu_flags);
	wake_up_interruptible_all(&instance->wait_queue);

	ME_SUBDEVICE_EXIT;

	return ME_ERRNO_SUCCESS;
	}

	static int me8200_do_io_single_config(me_subdevice_t *subdevice,
	struct file *filep,
	int channel,
	int single_config,
	int ref,
	int trig_chan,
	int trig_type, int trig_edge, int flags)
	{
	me8200_do_subdevice_t *instance;
	int err = ME_ERRNO_SUCCESS;
	unsigned long status;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	ME_SUBDEVICE_ENTER;

	spin_lock_irqsave(&instance->subdevice_lock, status);
	switch (flags) {
	case ME_IO_SINGLE_CONFIG_NO_FLAGS:
	case ME_IO_SINGLE_CONFIG_DIO_BYTE:
	if (channel == 0) {
	if (single_config == ME_SINGLE_CONFIG_DIO_OUTPUT) {
	} else {
	PERROR("Invalid byte direction specified.\n");
	err = ME_ERRNO_INVALID_SINGLE_CONFIG;
	}
	} else {
	PERROR("Invalid byte specified.\n");
	err = ME_ERRNO_INVALID_CHANNEL;
	}
	break;

	default:
	PERROR("Invalid flags specified.\n");
	err = ME_ERRNO_INVALID_FLAGS;
	}
	spin_unlock_irqrestore(&instance->subdevice_lock, status);

	ME_SUBDEVICE_EXIT;

	return err;
	}

	static int me8200_do_io_single_read(me_subdevice_t *subdevice,
	struct file *filep,
	int channel,
	int *value, int time_out, int flags)
	{
	me8200_do_subdevice_t *instance;
	int err = ME_ERRNO_SUCCESS;
	unsigned long status;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	ME_SUBDEVICE_ENTER;

	spin_lock_irqsave(&instance->subdevice_lock, status);
	switch (flags) {
	case ME_IO_SINGLE_TYPE_DIO_BIT:
	if ((channel >= 0) && (channel < 8)) {
	*value = inb(instance->port_reg) & (0x1 << channel);
	} else {
	PERROR("Invalid bit number specified.\n");
	err = ME_ERRNO_INVALID_CHANNEL;
	}
	break;

	case ME_IO_SINGLE_NO_FLAGS:
	case ME_IO_SINGLE_TYPE_DIO_BYTE:
	if (channel == 0) {
	*value = inb(instance->port_reg);
	} else {
	PERROR("Invalid byte number specified.\n");
	err = ME_ERRNO_INVALID_CHANNEL;
	}
	break;

	default:
	PERROR("Invalid flags specified.\n");
	err = ME_ERRNO_INVALID_FLAGS;
	}
	spin_unlock_irqrestore(&instance->subdevice_lock, status);

	ME_SUBDEVICE_EXIT;

	return err;
	}

	static int me8200_do_io_single_write(me_subdevice_t *subdevice,
	struct file *filep,
	int channel,
	int value, int time_out, int flags)
	{
	me8200_do_subdevice_t *instance;
	int err = ME_ERRNO_SUCCESS;
	uint8_t state;
	unsigned long status;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	ME_SUBDEVICE_ENTER;

	spin_lock_irqsave(&instance->subdevice_lock, status);
	switch (flags) {
	case ME_IO_SINGLE_TYPE_DIO_BIT:
	if ((channel >= 0) && (channel < 8)) {
	state = inb(instance->port_reg);
	state =
	value ? (state \| (0x1 << channel)) : (state &
	~(0x1 <<
	channel));
	outb(state, instance->port_reg);
	PDEBUG_REG("port_reg outb(0x%lX+0x%lX)=0x%x\n",
	instance->reg_base,
	instance->port_reg - instance->reg_base,
	state);
	} else {
	PERROR("Invalid bit number specified.\n");
	err = ME_ERRNO_INVALID_CHANNEL;
	}
	break;

	case ME_IO_SINGLE_NO_FLAGS:
	case ME_IO_SINGLE_TYPE_DIO_BYTE:
	if (channel == 0) {
	outb(value, instance->port_reg);
	PDEBUG_REG("port_reg outb(0x%lX+0x%lX)=0x%x\n",
	instance->reg_base,
	instance->port_reg - instance->reg_base,
	value);
	} else {
	PERROR("Invalid byte number specified.\n");
	err = ME_ERRNO_INVALID_CHANNEL;
	}
	break;

	default:
	PERROR("Invalid flags specified.\n");
	err = ME_ERRNO_INVALID_FLAGS;
	}
	spin_unlock_irqrestore(&instance->subdevice_lock, status);

	ME_SUBDEVICE_EXIT;

	return err;
	}

	static int me8200_do_query_number_channels(me_subdevice_t *subdevice,
	int *number)
	{
	PDEBUG("executed.\n");
	*number = 8;
	return ME_ERRNO_SUCCESS;
	}

	static int me8200_do_query_subdevice_type(me_subdevice_t *subdevice,
	int type, int subtype)
	{
	PDEBUG("executed.\n");
	*type = ME_TYPE_DO;
	*subtype = ME_SUBTYPE_SINGLE;
	return ME_ERRNO_SUCCESS;
	}

	static int me8200_do_query_subdevice_caps(me_subdevice_t subdevice, int caps)
	{
	PDEBUG("executed.\n");
	*caps = ME_CAPS_DIO_OVER_TEMP_IRQ;
	return ME_ERRNO_SUCCESS;
	}

	static void me8200_do_destructor(struct me_subdevice *subdevice)
	{
	me8200_do_subdevice_t *instance;

	PDEBUG("executed.\n");

	instance = (me8200_do_subdevice_t *) subdevice;

	free_irq(instance->irq, (void *)instance);
	me_subdevice_deinit(&instance->base);
	kfree(instance);
	}

	static irqreturn_t me8200_do_isr(int irq, void *dev_id)
	{
	me8200_do_subdevice_t *instance;
	uint16_t ctrl;
	uint8_t irq_status;

	instance = (me8200_do_subdevice_t *) dev_id;

	if (irq != instance->irq) {
	PERROR("Incorrect interrupt num: %d.\n", irq);
	return IRQ_NONE;
	}

	irq_status = inb(instance->irq_status_reg);
	if (!
	(irq_status &
	(ME8200_DO_IRQ_STATUS_BIT_ACTIVE << instance->do_idx))) {
	PINFO
	("%ld Shared interrupt. %s(): idx=%d irq_status_reg=0x%04X\n",
	jiffies, __func__, instance->do_idx, irq_status);
	return IRQ_NONE;
	}

	PDEBUG("executed.\n");

	spin_lock(&instance->subdevice_lock);
	instance->rised = 1;
	instance->count++;

	spin_lock(instance->irq_mode_lock);
	ctrl = inw(instance->irq_ctrl_reg);
	ctrl \|= ME8200_IRQ_MODE_BIT_CLEAR_POWER << instance->do_idx;
	outw(ctrl, instance->irq_ctrl_reg);
	PDEBUG_REG("irq_ctrl_reg outw(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
	instance->irq_ctrl_reg - instance->reg_base, ctrl);
	ctrl &= ~(ME8200_IRQ_MODE_BIT_CLEAR_POWER << instance->do_idx);
	outw(ctrl, instance->irq_ctrl_reg);
	PDEBUG_REG("irq_ctrl_reg outw(0x%lX+0x%lX)=0x%x\n", instance->reg_base,
	instance->irq_ctrl_reg - instance->reg_base, ctrl);
	spin_unlock(instance->irq_mode_lock);
	spin_unlock(&instance->subdevice_lock);
	wake_up_interruptible_all(&instance->wait_queue);

	return IRQ_HANDLED;
	}

	me8200_do_subdevice_t *me8200_do_constructor(uint32_t reg_base,
	unsigned int do_idx,
	int irq,
	spinlock_t *irq_mode_lock)
	{
	me8200_do_subdevice_t *subdevice;
	int err;

	PDEBUG("executed.\n");

	/* Allocate memory for subdevice instance */
	subdevice = kmalloc(sizeof(me8200_do_subdevice_t), GFP_KERNEL);

	if (!subdevice) {
	PERROR("Cannot get memory for subdevice instance.\n");
	return NULL;
	}

	memset(subdevice, 0, sizeof(me8200_do_subdevice_t));

	/* Initialize subdevice base class */
	err = me_subdevice_init(&subdevice->base);

	if (err) {
	PERROR("Cannot initialize subdevice base class instance.\n");
	kfree(subdevice);
	return NULL;
	}
	// Initialize spin locks.
	spin_lock_init(&subdevice->subdevice_lock);

	subdevice->irq_mode_lock = irq_mode_lock;

	/* Save the index of the digital output */
	subdevice->do_idx = do_idx;
	subdevice->irq = irq;

	/* Initialize the registers */
	if (do_idx == 0) {
	subdevice->port_reg = reg_base + ME8200_DO_PORT_0_REG;
	} else if (do_idx == 1) {
	subdevice->port_reg = reg_base + ME8200_DO_PORT_1_REG;
	} else {
	PERROR("Wrong subdevice idx=%d.\n", do_idx);
	kfree(subdevice);
	return NULL;
	}
	subdevice->irq_ctrl_reg = reg_base + ME8200_IRQ_MODE_REG;
	subdevice->irq_status_reg = reg_base + ME8200_DO_IRQ_STATUS_REG;
	#ifdef MEDEBUG_DEBUG_REG
	subdevice->reg_base = reg_base;
	#endif

	/* Initialize the wait queue */
	init_waitqueue_head(&subdevice->wait_queue);

	/* Request the interrupt line */
	err = request_irq(irq, me8200_do_isr,
	IRQF_DISABLED \| IRQF_SHARED,
	ME8200_NAME, (void *)subdevice);

	if (err) {
	PERROR("Cannot get interrupt line.\n");
	kfree(subdevice);
	return NULL;
	}
	PINFO("Registered irq=%d.\n", irq);

	/* Overload base class methods. */
	subdevice->base.me_subdevice_io_irq_start = me8200_do_io_irq_start;
	subdevice->base.me_subdevice_io_irq_wait = me8200_do_io_irq_wait;
	subdevice->base.me_subdevice_io_irq_stop = me8200_do_io_irq_stop;
	subdevice->base.me_subdevice_io_reset_subdevice =
	me8200_do_io_reset_subdevice;
	subdevice->base.me_subdevice_io_single_config =
	me8200_do_io_single_config;
	subdevice->base.me_subdevice_io_single_read = me8200_do_io_single_read;
	subdevice->base.me_subdevice_io_single_write =
	me8200_do_io_single_write;
	subdevice->base.me_subdevice_query_number_channels =
	me8200_do_query_number_channels;
	subdevice->base.me_subdevice_query_subdevice_type =
	me8200_do_query_subdevice_type;
	subdevice->base.me_subdevice_query_subdevice_caps =
	me8200_do_query_subdevice_caps;
	subdevice->base.me_subdevice_destructor = me8200_do_destructor;

	subdevice->rised = 0;
	subdevice->count = 0;

	return subdevice;
	}