text: /*
   *  linux/drivers/mfd/ucb1x00-core.c
   *
   *  Copyright (C) 2001 Russell King, 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.
   *
   *  The UCB1x00 core driver provides basic services for handling IO,
   *  the ADC, interrupts, and accessing registers.  It is designed
   *  such that everything goes through this layer, thereby providing
   *  a consistent locking methodology, as well as allowing the drivers
   *  to be used on other non-MCP-enabled hardware platforms.
   *
   *  Note that all locks are private to this file.  Nothing else may
   *  touch them.
   */
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/slab.h>
  #include <linux/init.h>
  #include <linux/errno.h>
  #include <linux/interrupt.h>
  #include <linux/device.h>
  #include <linux/mutex.h>
  #include <linux/mfd/ucb1x00.h>
  #include <linux/gpio.h>
  
  #include <mach/dma.h>
  #include <mach/hardware.h>
  
  static DEFINE_MUTEX(ucb1x00_mutex);
  static LIST_HEAD(ucb1x00_drivers);
  static LIST_HEAD(ucb1x00_devices);
  
  /**
   *	ucb1x00_io_set_dir - set IO direction
   *	@ucb: UCB1x00 structure describing chip
   *	@in:  bitfield of IO pins to be set as inputs
   *	@out: bitfield of IO pins to be set as outputs
   *
   *	Set the IO direction of the ten general purpose IO pins on
   *	the UCB1x00 chip.  The @in bitfield has priority over the
   *	@out bitfield, in that if you specify a pin as both input
   *	and output, it will end up as an input.
   *
   *	ucb1x00_enable must have been called to enable the comms
   *	before using this function.
   *
   *	This function takes a spinlock, disabling interrupts.
   */
  void ucb1x00_io_set_dir(struct ucb1x00 *ucb, unsigned int in, unsigned int out)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&ucb->io_lock, flags);
  	ucb->io_dir |= out;
  	ucb->io_dir &= ~in;
  
  	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
  	spin_unlock_irqrestore(&ucb->io_lock, flags);
  }
  
  /**
   *	ucb1x00_io_write - set or clear IO outputs
   *	@ucb:   UCB1x00 structure describing chip
   *	@set:   bitfield of IO pins to set to logic '1'
   *	@clear: bitfield of IO pins to set to logic '0'
   *
   *	Set the IO output state of the specified IO pins.  The value
   *	is retained if the pins are subsequently configured as inputs.
   *	The @clear bitfield has priority over the @set bitfield -
   *	outputs will be cleared.
   *
   *	ucb1x00_enable must have been called to enable the comms
   *	before using this function.
   *
   *	This function takes a spinlock, disabling interrupts.
   */
  void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&ucb->io_lock, flags);
  	ucb->io_out |= set;
  	ucb->io_out &= ~clear;
  
  	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
  	spin_unlock_irqrestore(&ucb->io_lock, flags);
  }
  
  /**
   *	ucb1x00_io_read - read the current state of the IO pins
   *	@ucb: UCB1x00 structure describing chip
   *
   *	Return a bitfield describing the logic state of the ten
   *	general purpose IO pins.
   *
   *	ucb1x00_enable must have been called to enable the comms
   *	before using this function.
   *
   *	This function does not take any semaphores or spinlocks.
   */
  unsigned int ucb1x00_io_read(struct ucb1x00 *ucb)
  {
  	return ucb1x00_reg_read(ucb, UCB_IO_DATA);
  }
  
  static void ucb1x00_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  {
  	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
  	unsigned long flags;
  
  	spin_lock_irqsave(&ucb->io_lock, flags);
  	if (value)
  		ucb->io_out |= 1 << offset;
  	else
  		ucb->io_out &= ~(1 << offset);
  
  	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
  	spin_unlock_irqrestore(&ucb->io_lock, flags);
  }
  
  static int ucb1x00_gpio_get(struct gpio_chip *chip, unsigned offset)
  {
  	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
  	return ucb1x00_reg_read(ucb, UCB_IO_DATA) & (1 << offset);
  }
  
  static int ucb1x00_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
  {
  	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
  	unsigned long flags;
  
  	spin_lock_irqsave(&ucb->io_lock, flags);
  	ucb->io_dir &= ~(1 << offset);
  	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
  	spin_unlock_irqrestore(&ucb->io_lock, flags);
  
  	return 0;
  }
  
  static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset
  		, int value)
  {
  	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
  	unsigned long flags;
  
  	spin_lock_irqsave(&ucb->io_lock, flags);
  	ucb->io_dir |= (1 << offset);
  	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
  
  	if (value)
  		ucb->io_out |= 1 << offset;
  	else
  		ucb->io_out &= ~(1 << offset);
  	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
  	spin_unlock_irqrestore(&ucb->io_lock, flags);
  
  	return 0;
  }
  
  /*
   * UCB1300 data sheet says we must:
   *  1. enable ADC	=> 5us (including reference startup time)
   *  2. select input	=> 51*tsibclk  => 4.3us
   *  3. start conversion	=> 102*tsibclk => 8.5us
   * (tsibclk = 1/11981000)
   * Period between SIB 128-bit frames = 10.7us
   */
  
  /**
   *	ucb1x00_adc_enable - enable the ADC converter
   *	@ucb: UCB1x00 structure describing chip
   *
   *	Enable the ucb1x00 and ADC converter on the UCB1x00 for use.
   *	Any code wishing to use the ADC converter must call this
   *	function prior to using it.
   *
   *	This function takes the ADC semaphore to prevent two or more
   *	concurrent uses, and therefore may sleep.  As a result, it
   *	can only be called from process context, not interrupt
   *	context.
   *
   *	You should release the ADC as soon as possible using
   *	ucb1x00_adc_disable.
   */
  void ucb1x00_adc_enable(struct ucb1x00 *ucb)
  {
  	down(&ucb->adc_sem);
  
  	ucb->adc_cr |= UCB_ADC_ENA;
  
  	ucb1x00_enable(ucb);
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
  }
  
  /**
   *	ucb1x00_adc_read - read the specified ADC channel
   *	@ucb: UCB1x00 structure describing chip
   *	@adc_channel: ADC channel mask
   *	@sync: wait for syncronisation pulse.
   *
   *	Start an ADC conversion and wait for the result.  Note that
   *	synchronised ADC conversions (via the ADCSYNC pin) must wait
   *	until the trigger is asserted and the conversion is finished.
   *
   *	This function currently spins waiting for the conversion to
   *	complete (2 frames max without sync).
   *
   *	If called for a synchronised ADC conversion, it may sleep
   *	with the ADC semaphore held.
   */
  unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync)
  {
  	unsigned int val;
  
  	if (sync)
  		adc_channel |= UCB_ADC_SYNC_ENA;
  
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel);
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel | UCB_ADC_START);
  
  	for (;;) {
  		val = ucb1x00_reg_read(ucb, UCB_ADC_DATA);
  		if (val & UCB_ADC_DAT_VAL)
  			break;
  		/* yield to other processes */
  		set_current_state(TASK_INTERRUPTIBLE);
  		schedule_timeout(1);
  	}
  
  	return UCB_ADC_DAT(val);
  }
  
  /**
   *	ucb1x00_adc_disable - disable the ADC converter
   *	@ucb: UCB1x00 structure describing chip
   *
   *	Disable the ADC converter and release the ADC semaphore.
   */
  void ucb1x00_adc_disable(struct ucb1x00 *ucb)
  {
  	ucb->adc_cr &= ~UCB_ADC_ENA;
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
  	ucb1x00_disable(ucb);
  
  	up(&ucb->adc_sem);
  }
  
  /*
   * UCB1x00 Interrupt handling.
   *
   * The UCB1x00 can generate interrupts when the SIBCLK is stopped.
   * Since we need to read an internal register, we must re-enable
   * SIBCLK to talk to the chip.  We leave the clock running until
   * we have finished processing all interrupts from the chip.
   */
  static irqreturn_t ucb1x00_irq(int irqnr, void *devid)
  {
  	struct ucb1x00 *ucb = devid;
  	struct ucb1x00_irq *irq;
  	unsigned int isr, i;
  
  	ucb1x00_enable(ucb);
  	isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
  	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
  	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
  
  	for (i = 0, irq = ucb->irq_handler; i < 16 && isr; i++, isr >>= 1, irq++)
  		if (isr & 1 && irq->fn)
  			irq->fn(i, irq->devid);
  	ucb1x00_disable(ucb);
  
  	return IRQ_HANDLED;
  }
  
  /**
   *	ucb1x00_hook_irq - hook a UCB1x00 interrupt
   *	@ucb:   UCB1x00 structure describing chip
   *	@idx:   interrupt index
   *	@fn:    function to call when interrupt is triggered
   *	@devid: device id to pass to interrupt handler
   *
   *	Hook the specified interrupt.  You can only register one handler
   *	for each interrupt source.  The interrupt source is not enabled
   *	by this function; use ucb1x00_enable_irq instead.
   *
   *	Interrupt handlers will be called with other interrupts enabled.
   *
   *	Returns zero on success, or one of the following errors:
   *	 -EINVAL if the interrupt index is invalid
   *	 -EBUSY if the interrupt has already been hooked
   */
  int ucb1x00_hook_irq(struct ucb1x00 *ucb, unsigned int idx, void (*fn)(int, void *), void *devid)
  {
  	struct ucb1x00_irq *irq;
  	int ret = -EINVAL;
  
  	if (idx < 16) {
  		irq = ucb->irq_handler + idx;
  		ret = -EBUSY;
  
  		spin_lock_irq(&ucb->lock);
  		if (irq->fn == NULL) {
  			irq->devid = devid;
  			irq->fn = fn;
  			ret = 0;
  		}
  		spin_unlock_irq(&ucb->lock);
  	}
  	return ret;
  }
  
  /**
   *	ucb1x00_enable_irq - enable an UCB1x00 interrupt source
   *	@ucb: UCB1x00 structure describing chip
   *	@idx: interrupt index
   *	@edges: interrupt edges to enable
   *
   *	Enable the specified interrupt to trigger on %UCB_RISING,
   *	%UCB_FALLING or both edges.  The interrupt should have been
   *	hooked by ucb1x00_hook_irq.
   */
  void ucb1x00_enable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
  {
  	unsigned long flags;
  
  	if (idx < 16) {
  		spin_lock_irqsave(&ucb->lock, flags);
  
  		ucb1x00_enable(ucb);
  		if (edges & UCB_RISING) {
  			ucb->irq_ris_enbl |= 1 << idx;
  			ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
  		}
  		if (edges & UCB_FALLING) {
  			ucb->irq_fal_enbl |= 1 << idx;
  			ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
  		}
  		ucb1x00_disable(ucb);
  		spin_unlock_irqrestore(&ucb->lock, flags);
  	}
  }
  
  /**
   *	ucb1x00_disable_irq - disable an UCB1x00 interrupt source
   *	@ucb: UCB1x00 structure describing chip
   *	@edges: interrupt edges to disable
   *
   *	Disable the specified interrupt triggering on the specified
   *	(%UCB_RISING, %UCB_FALLING or both) edges.
   */
  void ucb1x00_disable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
  {
  	unsigned long flags;
  
  	if (idx < 16) {
  		spin_lock_irqsave(&ucb->lock, flags);
  
  		ucb1x00_enable(ucb);
  		if (edges & UCB_RISING) {
  			ucb->irq_ris_enbl &= ~(1 << idx);
  			ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
  		}
  		if (edges & UCB_FALLING) {
  			ucb->irq_fal_enbl &= ~(1 << idx);
  			ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
  		}
  		ucb1x00_disable(ucb);
  		spin_unlock_irqrestore(&ucb->lock, flags);
  	}
  }
  
  /**
   *	ucb1x00_free_irq - disable and free the specified UCB1x00 interrupt
   *	@ucb: UCB1x00 structure describing chip
   *	@idx: interrupt index
   *	@devid: device id.
   *
   *	Disable the interrupt source and remove the handler.  devid must
   *	match the devid passed when hooking the interrupt.
   *
   *	Returns zero on success, or one of the following errors:
   *	 -EINVAL if the interrupt index is invalid
   *	 -ENOENT if devid does not match
   */
  int ucb1x00_free_irq(struct ucb1x00 *ucb, unsigned int idx, void *devid)
  {
  	struct ucb1x00_irq *irq;
  	int ret;
  
  	if (idx >= 16)
  		goto bad;
  
  	irq = ucb->irq_handler + idx;
  	ret = -ENOENT;
  
  	spin_lock_irq(&ucb->lock);
  	if (irq->devid == devid) {
  		ucb->irq_ris_enbl &= ~(1 << idx);
  		ucb->irq_fal_enbl &= ~(1 << idx);
  
  		ucb1x00_enable(ucb);
  		ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
  		ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
  		ucb1x00_disable(ucb);
  
  		irq->fn = NULL;
  		irq->devid = NULL;
  		ret = 0;
  	}
  	spin_unlock_irq(&ucb->lock);
  	return ret;
  
  bad:
  	printk(KERN_ERR "Freeing bad UCB1x00 irq %d\n", idx);
  	return -EINVAL;
  }
  
  static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
  {
  	struct ucb1x00_dev *dev;
  	int ret = -ENOMEM;
  
  	dev = kmalloc(sizeof(struct ucb1x00_dev), GFP_KERNEL);
  	if (dev) {
  		dev->ucb = ucb;
  		dev->drv = drv;
  
  		ret = drv->add(dev);
  
  		if (ret == 0) {
  			list_add(&dev->dev_node, &ucb->devs);
  			list_add(&dev->drv_node, &drv->devs);
  		} else {
  			kfree(dev);
  		}
  	}
  	return ret;
  }
  
  static void ucb1x00_remove_dev(struct ucb1x00_dev *dev)
  {
  	dev->drv->remove(dev);
  	list_del(&dev->dev_node);
  	list_del(&dev->drv_node);
  	kfree(dev);
  }
  
  /*
   * Try to probe our interrupt, rather than relying on lots of
   * hard-coded machine dependencies.  For reference, the expected
   * IRQ mappings are:
   *
   *  	Machine		Default IRQ
   *	adsbitsy	IRQ_GPCIN4
   *	cerf		IRQ_GPIO_UCB1200_IRQ
   *	flexanet	IRQ_GPIO_GUI
   *	freebird	IRQ_GPIO_FREEBIRD_UCB1300_IRQ
   *	graphicsclient	ADS_EXT_IRQ(8)
   *	graphicsmaster	ADS_EXT_IRQ(8)
   *	lart		LART_IRQ_UCB1200
   *	omnimeter	IRQ_GPIO23
   *	pfs168		IRQ_GPIO_UCB1300_IRQ
   *	simpad		IRQ_GPIO_UCB1300_IRQ
   *	shannon		SHANNON_IRQ_GPIO_IRQ_CODEC
   *	yopy		IRQ_GPIO_UCB1200_IRQ
   */
  static int ucb1x00_detect_irq(struct ucb1x00 *ucb)
  {
  	unsigned long mask;
  
  	mask = probe_irq_on();
  	if (!mask) {
  		probe_irq_off(mask);
  		return NO_IRQ;
  	}
  
  	/*
  	 * Enable the ADC interrupt.
  	 */
  	ucb1x00_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
  	ucb1x00_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
  	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
  	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
  
  	/*
  	 * Cause an ADC interrupt.
  	 */
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
  
  	/*
  	 * Wait for the conversion to complete.
  	 */
  	while ((ucb1x00_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VAL) == 0);
  	ucb1x00_reg_write(ucb, UCB_ADC_CR, 0);
  
  	/*
  	 * Disable and clear interrupt.
  	 */
  	ucb1x00_reg_write(ucb, UCB_IE_RIS, 0);
  	ucb1x00_reg_write(ucb, UCB_IE_FAL, 0);
  	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
  	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
  
  	/*
  	 * Read triggered interrupt.
  	 */
  	return probe_irq_off(mask);
  }
  
  static void ucb1x00_release(struct device *dev)
  {
  	struct ucb1x00 *ucb = classdev_to_ucb1x00(dev);
  	kfree(ucb);
  }
  
  static struct class ucb1x00_class = {
  	.name		= "ucb1x00",
  	.dev_release	= ucb1x00_release,
  };
  
  static int ucb1x00_probe(struct mcp *mcp)
  {
  	struct ucb1x00 *ucb;
  	struct ucb1x00_driver *drv;
  	unsigned int id;
  	int ret = -ENODEV;
  	int temp;
  
  	mcp_enable(mcp);
  	id = mcp_reg_read(mcp, UCB_ID);
  
  	if (id != UCB_ID_1200 && id != UCB_ID_1300 && id != UCB_ID_TC35143) {
  		printk(KERN_WARNING "UCB1x00 ID not found: %04x\n", id);
  		goto err_disable;
  	}
  
  	ucb = kzalloc(sizeof(struct ucb1x00), GFP_KERNEL);
  	ret = -ENOMEM;
  	if (!ucb)
  		goto err_disable;
  
  
  	ucb->dev.class = &ucb1x00_class;
  	ucb->dev.parent = &mcp->attached_device;
  	dev_set_name(&ucb->dev, "ucb1x00");
  
  	spin_lock_init(&ucb->lock);
  	spin_lock_init(&ucb->io_lock);
  	sema_init(&ucb->adc_sem, 1);
  
  	ucb->id  = id;
  	ucb->mcp = mcp;
  	ucb->irq = ucb1x00_detect_irq(ucb);
  	if (ucb->irq == NO_IRQ) {
  		printk(KERN_ERR "UCB1x00: IRQ probe failed\n");
  		ret = -ENODEV;
  		goto err_free;
  	}
  
  	ucb->gpio.base = -1;
  	if (mcp->gpio_base != 0) {
  		ucb->gpio.label = dev_name(&ucb->dev);
  		ucb->gpio.base = mcp->gpio_base;
  		ucb->gpio.ngpio = 10;
  		ucb->gpio.set = ucb1x00_gpio_set;
  		ucb->gpio.get = ucb1x00_gpio_get;
  		ucb->gpio.direction_input = ucb1x00_gpio_direction_input;
  		ucb->gpio.direction_output = ucb1x00_gpio_direction_output;
  		ret = gpiochip_add(&ucb->gpio);
  		if (ret)
  			goto err_free;
  	} else
  		dev_info(&ucb->dev, "gpio_base not set so no gpiolib support");
  
  	ret = request_irq(ucb->irq, ucb1x00_irq, IRQF_TRIGGER_RISING,
  			  "UCB1x00", ucb);
  	if (ret) {
  		printk(KERN_ERR "ucb1x00: unable to grab irq%d: %d\n",
  			ucb->irq, ret);
  		goto err_gpio;
  	}
  
  	mcp_set_drvdata(mcp, ucb);
  
  	ret = device_register(&ucb->dev);
  	if (ret)
  		goto err_irq;
  
  
  	INIT_LIST_HEAD(&ucb->devs);
  	mutex_lock(&ucb1x00_mutex);
  	list_add(&ucb->node, &ucb1x00_devices);
  	list_for_each_entry(drv, &ucb1x00_drivers, node) {
  		ucb1x00_add_dev(ucb, drv);
  	}
  	mutex_unlock(&ucb1x00_mutex);
  
  	goto out;
  
   err_irq:
  	free_irq(ucb->irq, ucb);
   err_gpio:
  	if (ucb->gpio.base != -1)
  		temp = gpiochip_remove(&ucb->gpio);
   err_free:
  	kfree(ucb);
   err_disable:
  	mcp_disable(mcp);
   out:
  	return ret;
  }
  
  static void ucb1x00_remove(struct mcp *mcp)
  {
  	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
  	struct list_head *l, *n;
  	int ret;
  
  	mutex_lock(&ucb1x00_mutex);
  	list_del(&ucb->node);
  	list_for_each_safe(l, n, &ucb->devs) {
  		struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, dev_node);
  		ucb1x00_remove_dev(dev);
  	}
  	mutex_unlock(&ucb1x00_mutex);
  
  	if (ucb->gpio.base != -1) {
  		ret = gpiochip_remove(&ucb->gpio);
  		if (ret)
  			dev_err(&ucb->dev, "Can't remove gpio chip: %d\n", ret);
  	}
  
  	free_irq(ucb->irq, ucb);
  	device_unregister(&ucb->dev);
  }
  
  int ucb1x00_register_driver(struct ucb1x00_driver *drv)
  {
  	struct ucb1x00 *ucb;
  
  	INIT_LIST_HEAD(&drv->devs);
  	mutex_lock(&ucb1x00_mutex);
  	list_add(&drv->node, &ucb1x00_drivers);
  	list_for_each_entry(ucb, &ucb1x00_devices, node) {
  		ucb1x00_add_dev(ucb, drv);
  	}
  	mutex_unlock(&ucb1x00_mutex);
  	return 0;
  }
  
  void ucb1x00_unregister_driver(struct ucb1x00_driver *drv)
  {
  	struct list_head *n, *l;
  
  	mutex_lock(&ucb1x00_mutex);
  	list_del(&drv->node);
  	list_for_each_safe(l, n, &drv->devs) {
  		struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, drv_node);
  		ucb1x00_remove_dev(dev);
  	}
  	mutex_unlock(&ucb1x00_mutex);
  }
  
  static int ucb1x00_suspend(struct mcp *mcp, pm_message_t state)
  {
  	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
  	struct ucb1x00_dev *dev;
  
  	mutex_lock(&ucb1x00_mutex);
  	list_for_each_entry(dev, &ucb->devs, dev_node) {
  		if (dev->drv->suspend)
  			dev->drv->suspend(dev, state);
  	}
  	mutex_unlock(&ucb1x00_mutex);
  	return 0;
  }
  
  static int ucb1x00_resume(struct mcp *mcp)
  {
  	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
  	struct ucb1x00_dev *dev;
  
  	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
  	mutex_lock(&ucb1x00_mutex);
  	list_for_each_entry(dev, &ucb->devs, dev_node) {
  		if (dev->drv->resume)
  			dev->drv->resume(dev);
  	}
  	mutex_unlock(&ucb1x00_mutex);
  	return 0;
  }
  
  static struct mcp_driver ucb1x00_driver = {
  	.drv		= {
  		.name	= "ucb1x00",
  	},
  	.probe		= ucb1x00_probe,
  	.remove		= ucb1x00_remove,
  	.suspend	= ucb1x00_suspend,
  	.resume		= ucb1x00_resume,
  };
  
  static int __init ucb1x00_init(void)
  {
  	int ret = class_register(&ucb1x00_class);
  	if (ret == 0) {
  		ret = mcp_driver_register(&ucb1x00_driver);
  		if (ret)
  			class_unregister(&ucb1x00_class);
  	}
  	return ret;
  }
  
  static void __exit ucb1x00_exit(void)
  {
  	mcp_driver_unregister(&ucb1x00_driver);
  	class_unregister(&ucb1x00_class);
  }
  
  module_init(ucb1x00_init);
  module_exit(ucb1x00_exit);
  
  EXPORT_SYMBOL(ucb1x00_io_set_dir);
  EXPORT_SYMBOL(ucb1x00_io_write);
  EXPORT_SYMBOL(ucb1x00_io_read);
  
  EXPORT_SYMBOL(ucb1x00_adc_enable);
  EXPORT_SYMBOL(ucb1x00_adc_read);
  EXPORT_SYMBOL(ucb1x00_adc_disable);
  
  EXPORT_SYMBOL(ucb1x00_hook_irq);
  EXPORT_SYMBOL(ucb1x00_free_irq);
  EXPORT_SYMBOL(ucb1x00_enable_irq);
  EXPORT_SYMBOL(ucb1x00_disable_irq);
  
  EXPORT_SYMBOL(ucb1x00_register_driver);
  EXPORT_SYMBOL(ucb1x00_unregister_driver);
  
  MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
  MODULE_DESCRIPTION("UCB1x00 core driver");
  MODULE_LICENSE("GPL");
  