text: /*
   * Register map access API
   *
   * Copyright 2011 Wolfson Microelectronics plc
   *
   * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  
  #include <linux/device.h>
  #include <linux/slab.h>
  #include <linux/export.h>
  #include <linux/mutex.h>
  #include <linux/err.h>
  #include <linux/rbtree.h>
  #include <linux/sched.h>
  
  #define CREATE_TRACE_POINTS
  #include <trace/events/regmap.h>
  
  #include "internal.h"
  
  /*
   * Sometimes for failures during very early init the trace
   * infrastructure isn't available early enough to be used.  For this
   * sort of problem defining LOG_DEVICE will add printks for basic
   * register I/O on a specific device.
   */
  #undef LOG_DEVICE
  
  static int _regmap_update_bits(struct regmap *map, unsigned int reg,
  			       unsigned int mask, unsigned int val,
  			       bool *change);
  
  static int _regmap_bus_read(void *context, unsigned int reg,
  			    unsigned int *val);
  static int _regmap_bus_formatted_write(void *context, unsigned int reg,
  				       unsigned int val);
  static int _regmap_bus_raw_write(void *context, unsigned int reg,
  				 unsigned int val);
  
  static void async_cleanup(struct work_struct *work)
  {
  	struct regmap_async *async = container_of(work, struct regmap_async,
  						  cleanup);
  
  	kfree(async->work_buf);
  	kfree(async);
  }
  
  bool regmap_reg_in_ranges(unsigned int reg,
  			  const struct regmap_range *ranges,
  			  unsigned int nranges)
  {
  	const struct regmap_range *r;
  	int i;
  
  	for (i = 0, r = ranges; i < nranges; i++, r++)
  		if (regmap_reg_in_range(reg, r))
  			return true;
  	return false;
  }
  EXPORT_SYMBOL_GPL(regmap_reg_in_ranges);
  
  static bool _regmap_check_range_table(struct regmap *map,
  				      unsigned int reg,
  				      const struct regmap_access_table *table)
  {
  	/* Check "no ranges" first */
  	if (regmap_reg_in_ranges(reg, table->no_ranges, table->n_no_ranges))
  		return false;
  
  	/* In case zero "yes ranges" are supplied, any reg is OK */
  	if (!table->n_yes_ranges)
  		return true;
  
  	return regmap_reg_in_ranges(reg, table->yes_ranges,
  				    table->n_yes_ranges);
  }
  
  bool regmap_writeable(struct regmap *map, unsigned int reg)
  {
  	if (map->max_register && reg > map->max_register)
  		return false;
  
  	if (map->writeable_reg)
  		return map->writeable_reg(map->dev, reg);
  
  	if (map->wr_table)
  		return _regmap_check_range_table(map, reg, map->wr_table);
  
  	return true;
  }
  
  bool regmap_readable(struct regmap *map, unsigned int reg)
  {
  	if (map->max_register && reg > map->max_register)
  		return false;
  
  	if (map->format.format_write)
  		return false;
  
  	if (map->readable_reg)
  		return map->readable_reg(map->dev, reg);
  
  	if (map->rd_table)
  		return _regmap_check_range_table(map, reg, map->rd_table);
  
  	return true;
  }
  
  bool regmap_volatile(struct regmap *map, unsigned int reg)
  {
  	if (!map->format.format_write && !regmap_readable(map, reg))
  		return false;
  
  	if (map->volatile_reg)
  		return map->volatile_reg(map->dev, reg);
  
  	if (map->volatile_table)
  		return _regmap_check_range_table(map, reg, map->volatile_table);
  
  	if (map->cache_ops)
  		return false;
  	else
  		return true;
  }
  
  bool regmap_precious(struct regmap *map, unsigned int reg)
  {
  	if (!regmap_readable(map, reg))
  		return false;
  
  	if (map->precious_reg)
  		return map->precious_reg(map->dev, reg);
  
  	if (map->precious_table)
  		return _regmap_check_range_table(map, reg, map->precious_table);
  
  	return false;
  }
  
  static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
  	size_t num)
  {
  	unsigned int i;
  
  	for (i = 0; i < num; i++)
  		if (!regmap_volatile(map, reg + i))
  			return false;
  
  	return true;
  }
  
  static void regmap_format_2_6_write(struct regmap *map,
  				     unsigned int reg, unsigned int val)
  {
  	u8 *out = map->work_buf;
  
  	*out = (reg << 6) | val;
  }
  
  static void regmap_format_4_12_write(struct regmap *map,
  				     unsigned int reg, unsigned int val)
  {
  	__be16 *out = map->work_buf;
  	*out = cpu_to_be16((reg << 12) | val);
  }
  
  static void regmap_format_7_9_write(struct regmap *map,
  				    unsigned int reg, unsigned int val)
  {
  	__be16 *out = map->work_buf;
  	*out = cpu_to_be16((reg << 9) | val);
  }
  
  static void regmap_format_10_14_write(struct regmap *map,
  				    unsigned int reg, unsigned int val)
  {
  	u8 *out = map->work_buf;
  
  	out[2] = val;
  	out[1] = (val >> 8) | (reg << 6);
  	out[0] = reg >> 2;
  }
  
  static void regmap_format_8(void *buf, unsigned int val, unsigned int shift)
  {
  	u8 *b = buf;
  
  	b[0] = val << shift;
  }
  
  static void regmap_format_16_be(void *buf, unsigned int val, unsigned int shift)
  {
  	__be16 *b = buf;
  
  	b[0] = cpu_to_be16(val << shift);
  }
  
  static void regmap_format_16_native(void *buf, unsigned int val,
  				    unsigned int shift)
  {
  	*(u16 *)buf = val << shift;
  }
  
  static void regmap_format_24(void *buf, unsigned int val, unsigned int shift)
  {
  	u8 *b = buf;
  
  	val <<= shift;
  
  	b[0] = val >> 16;
  	b[1] = val >> 8;
  	b[2] = val;
  }
  
  static void regmap_format_32_be(void *buf, unsigned int val, unsigned int shift)
  {
  	__be32 *b = buf;
  
  	b[0] = cpu_to_be32(val << shift);
  }
  
  static void regmap_format_32_native(void *buf, unsigned int val,
  				    unsigned int shift)
  {
  	*(u32 *)buf = val << shift;
  }
  
  static void regmap_parse_inplace_noop(void *buf)
  {
  }
  
  static unsigned int regmap_parse_8(const void *buf)
  {
  	const u8 *b = buf;
  
  	return b[0];
  }
  
  static unsigned int regmap_parse_16_be(const void *buf)
  {
  	const __be16 *b = buf;
  
  	return be16_to_cpu(b[0]);
  }
  
  static void regmap_parse_16_be_inplace(void *buf)
  {
  	__be16 *b = buf;
  
  	b[0] = be16_to_cpu(b[0]);
  }
  
  static unsigned int regmap_parse_16_native(const void *buf)
  {
  	return *(u16 *)buf;
  }
  
  static unsigned int regmap_parse_24(const void *buf)
  {
  	const u8 *b = buf;
  	unsigned int ret = b[2];
  	ret |= ((unsigned int)b[1]) << 8;
  	ret |= ((unsigned int)b[0]) << 16;
  
  	return ret;
  }
  
  static unsigned int regmap_parse_32_be(const void *buf)
  {
  	const __be32 *b = buf;
  
  	return be32_to_cpu(b[0]);
  }
  
  static void regmap_parse_32_be_inplace(void *buf)
  {
  	__be32 *b = buf;
  
  	b[0] = be32_to_cpu(b[0]);
  }
  
  static unsigned int regmap_parse_32_native(const void *buf)
  {
  	return *(u32 *)buf;
  }
  
  static void regmap_lock_mutex(void *__map)
  {
  	struct regmap *map = __map;
  	mutex_lock(&map->mutex);
  }
  
  static void regmap_unlock_mutex(void *__map)
  {
  	struct regmap *map = __map;
  	mutex_unlock(&map->mutex);
  }
  
  static void regmap_lock_spinlock(void *__map)
  {
  	struct regmap *map = __map;
  	unsigned long flags;
  
  	spin_lock_irqsave(&map->spinlock, flags);
  	map->spinlock_flags = flags;
  }
  
  static void regmap_unlock_spinlock(void *__map)
  {
  	struct regmap *map = __map;
  	spin_unlock_irqrestore(&map->spinlock, map->spinlock_flags);
  }
  
  static void dev_get_regmap_release(struct device *dev, void *res)
  {
  	/*
  	 * We don't actually have anything to do here; the goal here
  	 * is not to manage the regmap but to provide a simple way to
  	 * get the regmap back given a struct device.
  	 */
  }
  
  static bool _regmap_range_add(struct regmap *map,
  			      struct regmap_range_node *data)
  {
  	struct rb_root *root = &map->range_tree;
  	struct rb_node **new = &(root->rb_node), *parent = NULL;
  
  	while (*new) {
  		struct regmap_range_node *this =
  			container_of(*new, struct regmap_range_node, node);
  
  		parent = *new;
  		if (data->range_max < this->range_min)
  			new = &((*new)->rb_left);
  		else if (data->range_min > this->range_max)
  			new = &((*new)->rb_right);
  		else
  			return false;
  	}
  
  	rb_link_node(&data->node, parent, new);
  	rb_insert_color(&data->node, root);
  
  	return true;
  }
  
  static struct regmap_range_node *_regmap_range_lookup(struct regmap *map,
  						      unsigned int reg)
  {
  	struct rb_node *node = map->range_tree.rb_node;
  
  	while (node) {
  		struct regmap_range_node *this =
  			container_of(node, struct regmap_range_node, node);
  
  		if (reg < this->range_min)
  			node = node->rb_left;
  		else if (reg > this->range_max)
  			node = node->rb_right;
  		else
  			return this;
  	}
  
  	return NULL;
  }
  
  static void regmap_range_exit(struct regmap *map)
  {
  	struct rb_node *next;
  	struct regmap_range_node *range_node;
  
  	next = rb_first(&map->range_tree);
  	while (next) {
  		range_node = rb_entry(next, struct regmap_range_node, node);
  		next = rb_next(&range_node->node);
  		rb_erase(&range_node->node, &map->range_tree);
  		kfree(range_node);
  	}
  
  	kfree(map->selector_work_buf);
  }
  
  /**
   * regmap_init(): Initialise register map
   *
   * @dev: Device that will be interacted with
   * @bus: Bus-specific callbacks to use with device
   * @bus_context: Data passed to bus-specific callbacks
   * @config: Configuration for register map
   *
   * The return value will be an ERR_PTR() on error or a valid pointer to
   * a struct regmap.  This function should generally not be called
   * directly, it should be called by bus-specific init functions.
   */
  struct regmap *regmap_init(struct device *dev,
  			   const struct regmap_bus *bus,
  			   void *bus_context,
  			   const struct regmap_config *config)
  {
  	struct regmap *map, **m;
  	int ret = -EINVAL;
  	enum regmap_endian reg_endian, val_endian;
  	int i, j;
  
  	if (!config)
  		goto err;
  
  	map = kzalloc(sizeof(*map), GFP_KERNEL);
  	if (map == NULL) {
  		ret = -ENOMEM;
  		goto err;
  	}
  
  	if (config->lock && config->unlock) {
  		map->lock = config->lock;
  		map->unlock = config->unlock;
  		map->lock_arg = config->lock_arg;
  	} else {
  		if ((bus && bus->fast_io) ||
  		    config->fast_io) {
  			spin_lock_init(&map->spinlock);
  			map->lock = regmap_lock_spinlock;
  			map->unlock = regmap_unlock_spinlock;
  		} else {
  			mutex_init(&map->mutex);
  			map->lock = regmap_lock_mutex;
  			map->unlock = regmap_unlock_mutex;
  		}
  		map->lock_arg = map;
  	}
  	map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
  	map->format.pad_bytes = config->pad_bits / 8;
  	map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
  	map->format.buf_size = DIV_ROUND_UP(config->reg_bits +
  			config->val_bits + config->pad_bits, 8);
  	map->reg_shift = config->pad_bits % 8;
  	if (config->reg_stride)
  		map->reg_stride = config->reg_stride;
  	else
  		map->reg_stride = 1;
  	map->use_single_rw = config->use_single_rw;
  	map->dev = dev;
  	map->bus = bus;
  	map->bus_context = bus_context;
  	map->max_register = config->max_register;
  	map->wr_table = config->wr_table;
  	map->rd_table = config->rd_table;
  	map->volatile_table = config->volatile_table;
  	map->precious_table = config->precious_table;
  	map->writeable_reg = config->writeable_reg;
  	map->readable_reg = config->readable_reg;
  	map->volatile_reg = config->volatile_reg;
  	map->precious_reg = config->precious_reg;
  	map->reg_volatile_set = config->reg_volatile_set;
  	map->cache_type = config->cache_type;
  	map->name = config->name;
  
  	spin_lock_init(&map->async_lock);
  	INIT_LIST_HEAD(&map->async_list);
  	init_waitqueue_head(&map->async_waitq);
  
  	if (config->read_flag_mask || config->write_flag_mask) {
  		map->read_flag_mask = config->read_flag_mask;
  		map->write_flag_mask = config->write_flag_mask;
  	} else if (bus) {
  		map->read_flag_mask = bus->read_flag_mask;
  	}
  
  	if (!bus) {
  		map->reg_read  = config->reg_read;
  		map->reg_write = config->reg_write;
  
  		map->defer_caching = false;
  		goto skip_format_initialization;
  	} else {
  		map->reg_read  = _regmap_bus_read;
  	}
  
  	reg_endian = config->reg_format_endian;
  	if (reg_endian == REGMAP_ENDIAN_DEFAULT)
  		reg_endian = bus->reg_format_endian_default;
  	if (reg_endian == REGMAP_ENDIAN_DEFAULT)
  		reg_endian = REGMAP_ENDIAN_BIG;
  
  	val_endian = config->val_format_endian;
  	if (val_endian == REGMAP_ENDIAN_DEFAULT)
  		val_endian = bus->val_format_endian_default;
  	if (val_endian == REGMAP_ENDIAN_DEFAULT)
  		val_endian = REGMAP_ENDIAN_BIG;
  
  	switch (config->reg_bits + map->reg_shift) {
  	case 2:
  		switch (config->val_bits) {
  		case 6:
  			map->format.format_write = regmap_format_2_6_write;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  
  	case 4:
  		switch (config->val_bits) {
  		case 12:
  			map->format.format_write = regmap_format_4_12_write;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  
  	case 7:
  		switch (config->val_bits) {
  		case 9:
  			map->format.format_write = regmap_format_7_9_write;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  
  	case 10:
  		switch (config->val_bits) {
  		case 14:
  			map->format.format_write = regmap_format_10_14_write;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  
  	case 8:
  		map->format.format_reg = regmap_format_8;
  		break;
  
  	case 16:
  		switch (reg_endian) {
  		case REGMAP_ENDIAN_BIG:
  			map->format.format_reg = regmap_format_16_be;
  			break;
  		case REGMAP_ENDIAN_NATIVE:
  			map->format.format_reg = regmap_format_16_native;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  
  	case 24:
  		if (reg_endian != REGMAP_ENDIAN_BIG)
  			goto err_map;
  		map->format.format_reg = regmap_format_24;
  		break;
  
  	case 32:
  		switch (reg_endian) {
  		case REGMAP_ENDIAN_BIG:
  			map->format.format_reg = regmap_format_32_be;
  			break;
  		case REGMAP_ENDIAN_NATIVE:
  			map->format.format_reg = regmap_format_32_native;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  
  	default:
  		goto err_map;
  	}
  
  	if (val_endian == REGMAP_ENDIAN_NATIVE)
  		map->format.parse_inplace = regmap_parse_inplace_noop;
  
  	switch (config->val_bits) {
  	case 8:
  		map->format.format_val = regmap_format_8;
  		map->format.parse_val = regmap_parse_8;
  		map->format.parse_inplace = regmap_parse_inplace_noop;
  		break;
  	case 16:
  		switch (val_endian) {
  		case REGMAP_ENDIAN_BIG:
  			map->format.format_val = regmap_format_16_be;
  			map->format.parse_val = regmap_parse_16_be;
  			map->format.parse_inplace = regmap_parse_16_be_inplace;
  			break;
  		case REGMAP_ENDIAN_NATIVE:
  			map->format.format_val = regmap_format_16_native;
  			map->format.parse_val = regmap_parse_16_native;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  	case 24:
  		if (val_endian != REGMAP_ENDIAN_BIG)
  			goto err_map;
  		map->format.format_val = regmap_format_24;
  		map->format.parse_val = regmap_parse_24;
  		break;
  	case 32:
  		switch (val_endian) {
  		case REGMAP_ENDIAN_BIG:
  			map->format.format_val = regmap_format_32_be;
  			map->format.parse_val = regmap_parse_32_be;
  			map->format.parse_inplace = regmap_parse_32_be_inplace;
  			break;
  		case REGMAP_ENDIAN_NATIVE:
  			map->format.format_val = regmap_format_32_native;
  			map->format.parse_val = regmap_parse_32_native;
  			break;
  		default:
  			goto err_map;
  		}
  		break;
  	}
  
  	if (map->format.format_write) {
  		if ((reg_endian != REGMAP_ENDIAN_BIG) ||
  		    (val_endian != REGMAP_ENDIAN_BIG))
  			goto err_map;
  		map->use_single_rw = true;
  	}
  
  	if (!map->format.format_write &&
  	    !(map->format.format_reg && map->format.format_val))
  		goto err_map;
  
  	map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
  	if (map->work_buf == NULL) {
  		ret = -ENOMEM;
  		goto err_map;
  	}
  
  	if (map->format.format_write) {
  		map->defer_caching = false;
  		map->reg_write = _regmap_bus_formatted_write;
  	} else if (map->format.format_val) {
  		map->defer_caching = true;
  		map->reg_write = _regmap_bus_raw_write;
  	}
  
  skip_format_initialization:
  
  	map->range_tree = RB_ROOT;
  	for (i = 0; i < config->num_ranges; i++) {
  		const struct regmap_range_cfg *range_cfg = &config->ranges[i];
  		struct regmap_range_node *new;
  
  		/* Sanity check */
  		if (range_cfg->range_max < range_cfg->range_min) {
  			dev_err(map->dev, "Invalid range %d: %d < %d\n", i,
  				range_cfg->range_max, range_cfg->range_min);
  			goto err_range;
  		}
  
  		if (range_cfg->range_max > map->max_register) {
  			dev_err(map->dev, "Invalid range %d: %d > %d\n", i,
  				range_cfg->range_max, map->max_register);
  			goto err_range;
  		}
  
  		if (range_cfg->selector_reg > map->max_register) {
  			dev_err(map->dev,
  				"Invalid range %d: selector out of map\n", i);
  			goto err_range;
  		}
  
  		if (range_cfg->window_len == 0) {
  			dev_err(map->dev, "Invalid range %d: window_len 0\n",
  				i);
  			goto err_range;
  		}
  
  		/* Make sure, that this register range has no selector
  		   or data window within its boundary */
  		for (j = 0; j < config->num_ranges; j++) {
  			unsigned sel_reg = config->ranges[j].selector_reg;
  			unsigned win_min = config->ranges[j].window_start;
  			unsigned win_max = win_min +
  					   config->ranges[j].window_len - 1;
  
  			if (range_cfg->range_min <= sel_reg &&
  			    sel_reg <= range_cfg->range_max) {
  				dev_err(map->dev,
  					"Range %d: selector for %d in window\n",
  					i, j);
  				goto err_range;
  			}
  
  			if (!(win_max < range_cfg->range_min ||
  			      win_min > range_cfg->range_max)) {
  				dev_err(map->dev,
  					"Range %d: window for %d in window\n",
  					i, j);
  				goto err_range;
  			}
  		}
  
  		new = kzalloc(sizeof(*new), GFP_KERNEL);
  		if (new == NULL) {
  			ret = -ENOMEM;
  			goto err_range;
  		}
  
  		new->map = map;
  		new->name = range_cfg->name;
  		new->range_min = range_cfg->range_min;
  		new->range_max = range_cfg->range_max;
  		new->selector_reg = range_cfg->selector_reg;
  		new->selector_mask = range_cfg->selector_mask;
  		new->selector_shift = range_cfg->selector_shift;
  		new->window_start = range_cfg->window_start;
  		new->window_len = range_cfg->window_len;
  
  		if (_regmap_range_add(map, new) == false) {
  			dev_err(map->dev, "Failed to add range %d\n", i);
  			kfree(new);
  			goto err_range;
  		}
  
  		if (map->selector_work_buf == NULL) {
  			map->selector_work_buf =
  				kzalloc(map->format.buf_size, GFP_KERNEL);
  			if (map->selector_work_buf == NULL) {
  				ret = -ENOMEM;
  				goto err_range;
  			}
  		}
  	}
  
  	regmap_debugfs_init(map, config->name);
  
  	ret = regcache_init(map, config);
  	if (ret != 0)
  		goto err_range;
  
  	/* Add a devres resource for dev_get_regmap() */
  	m = devres_alloc(dev_get_regmap_release, sizeof(*m), GFP_KERNEL);
  	if (!m) {
  		ret = -ENOMEM;
  		goto err_debugfs;
  	}
  	*m = map;
  	devres_add(dev, m);
  
  	return map;
  
  err_debugfs:
  	regmap_debugfs_exit(map);
  	regcache_exit(map);
  err_range:
  	regmap_range_exit(map);
  	kfree(map->work_buf);
  err_map:
  	kfree(map);
  err:
  	return ERR_PTR(ret);
  }
  EXPORT_SYMBOL_GPL(regmap_init);
  
  static void devm_regmap_release(struct device *dev, void *res)
  {
  	regmap_exit(*(struct regmap **)res);
  }
  
  /**
   * devm_regmap_init(): Initialise managed register map
   *
   * @dev: Device that will be interacted with
   * @bus: Bus-specific callbacks to use with device
   * @bus_context: Data passed to bus-specific callbacks
   * @config: Configuration for register map
   *
   * The return value will be an ERR_PTR() on error or a valid pointer
   * to a struct regmap.  This function should generally not be called
   * directly, it should be called by bus-specific init functions.  The
   * map will be automatically freed by the device management code.
   */
  struct regmap *devm_regmap_init(struct device *dev,
  				const struct regmap_bus *bus,
  				void *bus_context,
  				const struct regmap_config *config)
  {
  	struct regmap **ptr, *regmap;
  
  	ptr = devres_alloc(devm_regmap_release, sizeof(*ptr), GFP_KERNEL);
  	if (!ptr)
  		return ERR_PTR(-ENOMEM);
  
  	regmap = regmap_init(dev, bus, bus_context, config);
  	if (!IS_ERR(regmap)) {
  		*ptr = regmap;
  		devres_add(dev, ptr);
  	} else {
  		devres_free(ptr);
  	}
  
  	return regmap;
  }
  EXPORT_SYMBOL_GPL(devm_regmap_init);
  
  /**
   * regmap_reinit_cache(): Reinitialise the current register cache
   *
   * @map: Register map to operate on.
   * @config: New configuration.  Only the cache data will be used.
   *
   * Discard any existing register cache for the map and initialize a
   * new cache.  This can be used to restore the cache to defaults or to
   * update the cache configuration to reflect runtime discovery of the
   * hardware.
   *
   * No explicit locking is done here, the user needs to ensure that
   * this function will not race with other calls to regmap.
   */
  int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
  {
  	regcache_exit(map);
  	regmap_debugfs_exit(map);
  
  	map->max_register = config->max_register;
  	map->writeable_reg = config->writeable_reg;
  	map->readable_reg = config->readable_reg;
  	map->volatile_reg = config->volatile_reg;
  	map->precious_reg = config->precious_reg;
  	map->reg_volatile_set = config->reg_volatile_set;
  	map->cache_type = config->cache_type;
  
  	regmap_debugfs_init(map, config->name);
  
  	map->cache_bypass = false;
  	map->cache_only = false;
  
  	return regcache_init(map, config);
  }
  EXPORT_SYMBOL_GPL(regmap_reinit_cache);
  
  /**
   * regmap_exit(): Free a previously allocated register map
   */
  void regmap_exit(struct regmap *map)
  {
  	regcache_exit(map);
  	regmap_debugfs_exit(map);
  	regmap_range_exit(map);
  	if (map->bus && map->bus->free_context)
  		map->bus->free_context(map->bus_context);
  	kfree(map->work_buf);
  	kfree(map);
  }
  EXPORT_SYMBOL_GPL(regmap_exit);
  
  static int dev_get_regmap_match(struct device *dev, void *res, void *data)
  {
  	struct regmap **r = res;
  	if (!r || !*r) {
  		WARN_ON(!r || !*r);
  		return 0;
  	}
  
  	/* If the user didn't specify a name match any */
  	if (data)
  		return (*r)->name == data;
  	else
  		return 1;
  }
  
  /**
   * dev_get_regmap(): Obtain the regmap (if any) for a device
   *
   * @dev: Device to retrieve the map for
   * @name: Optional name for the register map, usually NULL.
   *
   * Returns the regmap for the device if one is present, or NULL.  If
   * name is specified then it must match the name specified when
   * registering the device, if it is NULL then the first regmap found
   * will be used.  Devices with multiple register maps are very rare,
   * generic code should normally not need to specify a name.
   */
  struct regmap *dev_get_regmap(struct device *dev, const char *name)
  {
  	struct regmap **r = devres_find(dev, dev_get_regmap_release,
  					dev_get_regmap_match, (void *)name);
  
  	if (!r)
  		return NULL;
  	return *r;
  }
  EXPORT_SYMBOL_GPL(dev_get_regmap);
  
  static int _regmap_select_page(struct regmap *map, unsigned int *reg,
  			       struct regmap_range_node *range,
  			       unsigned int val_num)
  {
  	void *orig_work_buf;
  	unsigned int win_offset;
  	unsigned int win_page;
  	bool page_chg;
  	int ret;
  
  	win_offset = (*reg - range->range_min) % range->window_len;
  	win_page = (*reg - range->range_min) / range->window_len;
  
  	if (val_num > 1) {
  		/* Bulk write shouldn't cross range boundary */
  		if (*reg + val_num - 1 > range->range_max)
  			return -EINVAL;
  
  		/* ... or single page boundary */
  		if (val_num > range->window_len - win_offset)
  			return -EINVAL;
  	}
  
  	/* It is possible to have selector register inside data window.
  	   In that case, selector register is located on every page and
  	   it needs no page switching, when accessed alone. */
  	if (val_num > 1 ||
  	    range->window_start + win_offset != range->selector_reg) {
  		/* Use separate work_buf during page switching */
  		orig_work_buf = map->work_buf;
  		map->work_buf = map->selector_work_buf;
  
  		ret = _regmap_update_bits(map, range->selector_reg,
  					  range->selector_mask,
  					  win_page << range->selector_shift,
  					  &page_chg);
  
  		map->work_buf = orig_work_buf;
  
  		if (ret != 0)
  			return ret;
  	}
  
  	*reg = range->window_start + win_offset;
  
  	return 0;
  }
  
  int _regmap_raw_write(struct regmap *map, unsigned int reg,
  		      const void *val, size_t val_len, bool async)
  {
  	struct regmap_range_node *range;
  	unsigned long flags;
  	u8 *u8 = map->work_buf;
  	void *work_val = map->work_buf + map->format.reg_bytes +
  		map->format.pad_bytes;
  	void *buf;
  	int ret = -ENOTSUPP;
  	size_t len;
  	int i;
  
  	WARN_ON(!map->bus);
  
  	/* Check for unwritable registers before we start */
  	if (map->writeable_reg)
  		for (i = 0; i < val_len / map->format.val_bytes; i++)
  			if (!map->writeable_reg(map->dev,
  						reg + (i * map->reg_stride)))
  				return -EINVAL;
  
  	if (!map->cache_bypass && map->format.parse_val) {
  		unsigned int ival;
  		int val_bytes = map->format.val_bytes;
  		for (i = 0; i < val_len / val_bytes; i++) {
  			ival = map->format.parse_val(val + (i * val_bytes));
  			ret = regcache_write(map, reg + (i * map->reg_stride),
  					     ival);
  			if (ret) {
  				dev_err(map->dev,
  					"Error in caching of register: %x ret: %d\n",
  					reg + i, ret);
  				return ret;
  			}
  		}
  		if (map->cache_only) {
  			map->cache_dirty = true;
  			return 0;
  		}
  	}
  
  	range = _regmap_range_lookup(map, reg);
  	if (range) {
  		int val_num = val_len / map->format.val_bytes;
  		int win_offset = (reg - range->range_min) % range->window_len;
  		int win_residue = range->window_len - win_offset;
  
  		/* If the write goes beyond the end of the window split it */
  		while (val_num > win_residue) {
  			dev_dbg(map->dev, "Writing window %d/%zu\n",
  				win_residue, val_len / map->format.val_bytes);
  			ret = _regmap_raw_write(map, reg, val, win_residue *
  						map->format.val_bytes, async);
  			if (ret != 0)
  				return ret;
  
  			reg += win_residue;
  			val_num -= win_residue;
  			val += win_residue * map->format.val_bytes;
  			val_len -= win_residue * map->format.val_bytes;
  
  			win_offset = (reg - range->range_min) %
  				range->window_len;
  			win_residue = range->window_len - win_offset;
  		}
  
  		ret = _regmap_select_page(map, &reg, range, val_num);
  		if (ret != 0)
  			return ret;
  	}
  
  	map->format.format_reg(map->work_buf, reg, map->reg_shift);
  
  	u8[0] |= map->write_flag_mask;
  
  	if (async && map->bus->async_write) {
  		struct regmap_async *async = map->bus->async_alloc();
  		if (!async)
  			return -ENOMEM;
  
  		trace_regmap_async_write_start(map->dev, reg, val_len);
  
  		async->work_buf = kzalloc(map->format.buf_size,
  					  GFP_KERNEL | GFP_DMA);
  		if (!async->work_buf) {
  			kfree(async);
  			return -ENOMEM;
  		}
  
  		INIT_WORK(&async->cleanup, async_cleanup);
  		async->map = map;
  
  		/* If the caller supplied the value we can use it safely. */
  		memcpy(async->work_buf, map->work_buf, map->format.pad_bytes +
  		       map->format.reg_bytes + map->format.val_bytes);
  		if (val == work_val)
  			val = async->work_buf + map->format.pad_bytes +
  				map->format.reg_bytes;
  
  		spin_lock_irqsave(&map->async_lock, flags);
  		list_add_tail(&async->list, &map->async_list);
  		spin_unlock_irqrestore(&map->async_lock, flags);
  
  		ret = map->bus->async_write(map->bus_context, async->work_buf,
  					    map->format.reg_bytes +
  					    map->format.pad_bytes,
  					    val, val_len, async);
  
  		if (ret != 0) {
  			dev_err(map->dev, "Failed to schedule write: %d\n",
  				ret);
  
  			spin_lock_irqsave(&map->async_lock, flags);
  			list_del(&async->list);
  			spin_unlock_irqrestore(&map->async_lock, flags);
  
  			kfree(async->work_buf);
  			kfree(async);
  		}
  
  		return ret;
  	}
  
  	trace_regmap_hw_write_start(map->dev, reg,
  				    val_len / map->format.val_bytes);
  
  	/* If we're doing a single register write we can probably just
  	 * send the work_buf directly, otherwise try to do a gather
  	 * write.
  	 */
  	if (val == work_val)
  		ret = map->bus->write(map->bus_context, map->work_buf,
  				      map->format.reg_bytes +
  				      map->format.pad_bytes +
  				      val_len);
  	else if (map->bus->gather_write)
  		ret = map->bus->gather_write(map->bus_context, map->work_buf,
  					     map->format.reg_bytes +
  					     map->format.pad_bytes,
  					     val, val_len);
  
  	/* If that didn't work fall back on linearising by hand. */
  	if (ret == -ENOTSUPP) {
  		len = map->format.reg_bytes + map->format.pad_bytes + val_len;
  		buf = kzalloc(len, GFP_KERNEL);
  		if (!buf)
  			return -ENOMEM;
  
  		memcpy(buf, map->work_buf, map->format.reg_bytes);
  		memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
  		       val, val_len);
  		ret = map->bus->write(map->bus_context, buf, len);
  
  		kfree(buf);
  	}
  
  	trace_regmap_hw_write_done(map->dev, reg,
  				   val_len / map->format.val_bytes);
  
  	return ret;
  }
  
  /**
   * regmap_can_raw_write - Test if regmap_raw_write() is supported
   *
   * @map: Map to check.
   */
  bool regmap_can_raw_write(struct regmap *map)
  {
  	return map->bus && map->format.format_val && map->format.format_reg;
  }
  EXPORT_SYMBOL_GPL(regmap_can_raw_write);
  
  static int _regmap_bus_formatted_write(void *context, unsigned int reg,
  				       unsigned int val)
  {
  	int ret;
  	struct regmap_range_node *range;
  	struct regmap *map = context;
  
  	WARN_ON(!map->bus || !map->format.format_write);
  
  	range = _regmap_range_lookup(map, reg);
  	if (range) {
  		ret = _regmap_select_page(map, &reg, range, 1);
  		if (ret != 0)
  			return ret;
  	}
  
  	map->format.format_write(map, reg, val);
  
  	trace_regmap_hw_write_start(map->dev, reg, 1);
  
  	ret = map->bus->write(map->bus_context, map->work_buf,
  			      map->format.buf_size);
  
  	trace_regmap_hw_write_done(map->dev, reg, 1);
  
  	return ret;
  }
  
  static int _regmap_bus_raw_write(void *context, unsigned int reg,
  				 unsigned int val)
  {
  	struct regmap *map = context;
  
  	WARN_ON(!map->bus || !map->format.format_val);
  
  	map->format.format_val(map->work_buf + map->format.reg_bytes
  			       + map->format.pad_bytes, val, 0);
  	return _regmap_raw_write(map, reg,
  				 map->work_buf +
  				 map->format.reg_bytes +
  				 map->format.pad_bytes,
  				 map->format.val_bytes, false);
  }
  
  static inline void *_regmap_map_get_context(struct regmap *map)
  {
  	return (map->bus) ? map : map->bus_context;
  }
  
  int _regmap_write(struct regmap *map, unsigned int reg,
  		  unsigned int val)
  {
  	int ret;
  	void *context = _regmap_map_get_context(map);
  
  	if (!map->cache_bypass && !map->defer_caching) {
  		ret = regcache_write(map, reg, val);
  		if (ret != 0)
  			return ret;
  		if (map->cache_only) {
  			map->cache_dirty = true;
  			return 0;
  		}
  	}
  
  #ifdef LOG_DEVICE
  	if (map->dev && strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
  		dev_info(map->dev, "%x <= %x\n", reg, val);
  #endif
  
  	trace_regmap_reg_write(map->dev, reg, val);
  
  	return map->reg_write(context, reg, val);
  }
  
  /**
   * regmap_write(): Write a value to a single register
   *
   * @map: Register map to write to
   * @reg: Register to write to
   * @val: Value to be written
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
  {
  	int ret;
  
  	if (reg % map->reg_stride)
  		return -EINVAL;
  
  	map->lock(map->lock_arg);
  
  	ret = _regmap_write(map, reg, val);
  
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_write);
  
  /**
   * regmap_raw_write(): Write raw values to one or more registers
   *
   * @map: Register map to write to
   * @reg: Initial register to write to
   * @val: Block of data to be written, laid out for direct transmission to the
   *       device
   * @val_len: Length of data pointed to by val.
   *
   * This function is intended to be used for things like firmware
   * download where a large block of data needs to be transferred to the
   * device.  No formatting will be done on the data provided.
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_raw_write(struct regmap *map, unsigned int reg,
  		     const void *val, size_t val_len)
  {
  	int ret;
  
  	if (!regmap_can_raw_write(map))
  		return -EINVAL;
  	if (val_len % map->format.val_bytes)
  		return -EINVAL;
  
  	map->lock(map->lock_arg);
  
  	ret = _regmap_raw_write(map, reg, val, val_len, false);
  
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_raw_write);
  
  /*
   * regmap_bulk_write(): Write multiple registers to the device
   *
   * @map: Register map to write to
   * @reg: First register to be write from
   * @val: Block of data to be written, in native register size for device
   * @val_count: Number of registers to write
   *
   * This function is intended to be used for writing a large block of
   * data to the device either in single transfer or multiple transfer.
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
  		     size_t val_count)
  {
  	int ret = 0, i;
  	size_t val_bytes = map->format.val_bytes;
  	void *wval;
  
  	if (!map->bus)
  		return -EINVAL;
  	if (!map->format.parse_inplace)
  		return -EINVAL;
  	if (reg % map->reg_stride)
  		return -EINVAL;
  
  	map->lock(map->lock_arg);
  
  	/* No formatting is require if val_byte is 1 */
  	if (val_bytes == 1) {
  		wval = (void *)val;
  	} else {
  		wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
  		if (!wval) {
  			ret = -ENOMEM;
  			dev_err(map->dev, "Error in memory allocation\n");
  			goto out;
  		}
  		for (i = 0; i < val_count * val_bytes; i += val_bytes)
  			map->format.parse_inplace(wval + i);
  	}
  	/*
  	 * Some devices does not support bulk write, for
  	 * them we have a series of single write operations.
  	 */
  	if (map->use_single_rw) {
  		for (i = 0; i < val_count; i++) {
  			ret = regmap_raw_write(map,
  					       reg + (i * map->reg_stride),
  					       val + (i * val_bytes),
  					       val_bytes);
  			if (ret != 0)
  				return ret;
  		}
  	} else {
  		ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count,
  					false);
  	}
  
  	if (val_bytes != 1)
  		kfree(wval);
  
  out:
  	map->unlock(map->lock_arg);
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_bulk_write);
  
  /**
   * regmap_raw_write_async(): Write raw values to one or more registers
   *                           asynchronously
   *
   * @map: Register map to write to
   * @reg: Initial register to write to
   * @val: Block of data to be written, laid out for direct transmission to the
   *       device.  Must be valid until regmap_async_complete() is called.
   * @val_len: Length of data pointed to by val.
   *
   * This function is intended to be used for things like firmware
   * download where a large block of data needs to be transferred to the
   * device.  No formatting will be done on the data provided.
   *
   * If supported by the underlying bus the write will be scheduled
   * asynchronously, helping maximise I/O speed on higher speed buses
   * like SPI.  regmap_async_complete() can be called to ensure that all
   * asynchrnous writes have been completed.
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_raw_write_async(struct regmap *map, unsigned int reg,
  			   const void *val, size_t val_len)
  {
  	int ret;
  
  	if (val_len % map->format.val_bytes)
  		return -EINVAL;
  	if (reg % map->reg_stride)
  		return -EINVAL;
  
  	map->lock(map->lock_arg);
  
  	ret = _regmap_raw_write(map, reg, val, val_len, true);
  
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_raw_write_async);
  
  static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
  			    unsigned int val_len)
  {
  	struct regmap_range_node *range;
  	u8 *u8 = map->work_buf;
  	int ret;
  
  	WARN_ON(!map->bus);
  
  	range = _regmap_range_lookup(map, reg);
  	if (range) {
  		ret = _regmap_select_page(map, &reg, range,
  					  val_len / map->format.val_bytes);
  		if (ret != 0)
  			return ret;
  	}
  
  	map->format.format_reg(map->work_buf, reg, map->reg_shift);
  
  	/*
  	 * Some buses or devices flag reads by setting the high bits in the
  	 * register addresss; since it's always the high bits for all
  	 * current formats we can do this here rather than in
  	 * formatting.  This may break if we get interesting formats.
  	 */
  	u8[0] |= map->read_flag_mask;
  
  	trace_regmap_hw_read_start(map->dev, reg,
  				   val_len / map->format.val_bytes);
  
  	ret = map->bus->read(map->bus_context, map->work_buf,
  			     map->format.reg_bytes + map->format.pad_bytes,
  			     val, val_len);
  
  	trace_regmap_hw_read_done(map->dev, reg,
  				  val_len / map->format.val_bytes);
  
  	return ret;
  }
  
  static int _regmap_bus_read(void *context, unsigned int reg,
  			    unsigned int *val)
  {
  	int ret;
  	struct regmap *map = context;
  
  	if (!map->format.parse_val)
  		return -EINVAL;
  
  	ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
  	if (ret == 0)
  		*val = map->format.parse_val(map->work_buf);
  
  	return ret;
  }
  
  static int _regmap_read(struct regmap *map, unsigned int reg,
  			unsigned int *val)
  {
  	int ret;
  	void *context = _regmap_map_get_context(map);
  
  	WARN_ON(!map->reg_read);
  
  	if (!map->cache_bypass) {
  		ret = regcache_read(map, reg, val);
  		if (ret == 0)
  			return 0;
  	}
  
  	if (map->cache_only)
  		return -EBUSY;
  
  	ret = map->reg_read(context, reg, val);
  	if (ret == 0) {
  #ifdef LOG_DEVICE
  		if (map->dev && strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
  			dev_info(map->dev, "%x => %x\n", reg, *val);
  #endif
  
  		trace_regmap_reg_read(map->dev, reg, *val);
  
  		if (!map->cache_bypass)
  			regcache_write(map, reg, *val);
  	}
  
  	return ret;
  }
  
  /**
   * regmap_read(): Read a value from a single register
   *
   * @map: Register map to write to
   * @reg: Register to be read from
   * @val: Pointer to store read value
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
  {
  	int ret;
  
  	if (reg % map->reg_stride)
  		return -EINVAL;
  
  	map->lock(map->lock_arg);
  
  	ret = _regmap_read(map, reg, val);
  
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_read);
  
  /**
   * regmap_raw_read(): Read raw data from the device
   *
   * @map: Register map to write to
   * @reg: First register to be read from
   * @val: Pointer to store read value
   * @val_len: Size of data to read
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
  		    size_t val_len)
  {
  	size_t val_bytes = map->format.val_bytes;
  	size_t val_count = val_len / val_bytes;
  	unsigned int v;
  	int ret, i;
  
  	if (!map->bus)
  		return -EINVAL;
  	if (val_len % map->format.val_bytes)
  		return -EINVAL;
  	if (reg % map->reg_stride)
  		return -EINVAL;
  
  	map->lock(map->lock_arg);
  
  	if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
  	    map->cache_type == REGCACHE_NONE) {
  		/* Physical block read if there's no cache involved */
  		ret = _regmap_raw_read(map, reg, val, val_len);
  
  	} else {
  		/* Otherwise go word by word for the cache; should be low
  		 * cost as we expect to hit the cache.
  		 */
  		for (i = 0; i < val_count; i++) {
  			ret = _regmap_read(map, reg + (i * map->reg_stride),
  					   &v);
  			if (ret != 0)
  				goto out;
  
  			map->format.format_val(val + (i * val_bytes), v, 0);
  		}
  	}
  
   out:
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_raw_read);
  
  /**
   * regmap_bulk_read(): Read multiple registers from the device
   *
   * @map: Register map to write to
   * @reg: First register to be read from
   * @val: Pointer to store read value, in native register size for device
   * @val_count: Number of registers to read
   *
   * A value of zero will be returned on success, a negative errno will
   * be returned in error cases.
   */
  int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
  		     size_t val_count)
  {
  	int ret, i;
  	size_t val_bytes = map->format.val_bytes;
  	bool vol = regmap_volatile_range(map, reg, val_count);
  
  	if (!map->bus)
  		return -EINVAL;
  	if (!map->format.parse_inplace)
  		return -EINVAL;
  	if (reg % map->reg_stride)
  		return -EINVAL;
  
  	if (vol || map->cache_type == REGCACHE_NONE) {
  		/*
  		 * Some devices does not support bulk read, for
  		 * them we have a series of single read operations.
  		 */
  		if (map->use_single_rw) {
  			for (i = 0; i < val_count; i++) {
  				ret = regmap_raw_read(map,
  						reg + (i * map->reg_stride),
  						val + (i * val_bytes),
  						val_bytes);
  				if (ret != 0)
  					return ret;
  			}
  		} else {
  			ret = regmap_raw_read(map, reg, val,
  					      val_bytes * val_count);
  			if (ret != 0)
  				return ret;
  		}
  
  		for (i = 0; i < val_count * val_bytes; i += val_bytes)
  			map->format.parse_inplace(val + i);
  	} else {
  		for (i = 0; i < val_count; i++) {
  			unsigned int ival;
  			ret = regmap_read(map, reg + (i * map->reg_stride),
  					  &ival);
  			if (ret != 0)
  				return ret;
  			map->format.format_val(val + (i * val_bytes), ival, 0);
  		}
  	}
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(regmap_bulk_read);
  
  static int _regmap_update_bits(struct regmap *map, unsigned int reg,
  			       unsigned int mask, unsigned int val,
  			       bool *change)
  {
  	int ret;
  	unsigned int tmp, orig;
  
  	ret = _regmap_read(map, reg, &orig);
  	if (ret != 0)
  		return ret;
  
  	tmp = orig & ~mask;
  	tmp |= val & mask;
  
  	if (tmp != orig) {
  		ret = _regmap_write(map, reg, tmp);
  		*change = true;
  	} else {
  		*change = false;
  	}
  
  	return ret;
  }
  
  /**
   * regmap_update_bits: Perform a read/modify/write cycle on the register map
   *
   * @map: Register map to update
   * @reg: Register to update
   * @mask: Bitmask to change
   * @val: New value for bitmask
   *
   * Returns zero for success, a negative number on error.
   */
  int regmap_update_bits(struct regmap *map, unsigned int reg,
  		       unsigned int mask, unsigned int val)
  {
  	bool change;
  	int ret;
  
  	map->lock(map->lock_arg);
  	ret = _regmap_update_bits(map, reg, mask, val, &change);
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_update_bits);
  
  /**
   * regmap_update_bits_check: Perform a read/modify/write cycle on the
   *                           register map and report if updated
   *
   * @map: Register map to update
   * @reg: Register to update
   * @mask: Bitmask to change
   * @val: New value for bitmask
   * @change: Boolean indicating if a write was done
   *
   * Returns zero for success, a negative number on error.
   */
  int regmap_update_bits_check(struct regmap *map, unsigned int reg,
  			     unsigned int mask, unsigned int val,
  			     bool *change)
  {
  	int ret;
  
  	map->lock(map->lock_arg);
  	ret = _regmap_update_bits(map, reg, mask, val, change);
  	map->unlock(map->lock_arg);
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_update_bits_check);
  
  void regmap_async_complete_cb(struct regmap_async *async, int ret)
  {
  	struct regmap *map = async->map;
  	bool wake;
  
  	trace_regmap_async_io_complete(map->dev);
  
  	spin_lock(&map->async_lock);
  
  	list_del(&async->list);
  	wake = list_empty(&map->async_list);
  
  	if (ret != 0)
  		map->async_ret = ret;
  
  	spin_unlock(&map->async_lock);
  
  	schedule_work(&async->cleanup);
  
  	if (wake)
  		wake_up(&map->async_waitq);
  }
  EXPORT_SYMBOL_GPL(regmap_async_complete_cb);
  
  static int regmap_async_is_done(struct regmap *map)
  {
  	unsigned long flags;
  	int ret;
  
  	spin_lock_irqsave(&map->async_lock, flags);
  	ret = list_empty(&map->async_list);
  	spin_unlock_irqrestore(&map->async_lock, flags);
  
  	return ret;
  }
  
  /**
   * regmap_async_complete: Ensure all asynchronous I/O has completed.
   *
   * @map: Map to operate on.
   *
   * Blocks until any pending asynchronous I/O has completed.  Returns
   * an error code for any failed I/O operations.
   */
  int regmap_async_complete(struct regmap *map)
  {
  	unsigned long flags;
  	int ret;
  
  	/* Nothing to do with no async support */
  	if (!map->bus || !map->bus->async_write)
  		return 0;
  
  	trace_regmap_async_complete_start(map->dev);
  
  	wait_event(map->async_waitq, regmap_async_is_done(map));
  
  	spin_lock_irqsave(&map->async_lock, flags);
  	ret = map->async_ret;
  	map->async_ret = 0;
  	spin_unlock_irqrestore(&map->async_lock, flags);
  
  	trace_regmap_async_complete_done(map->dev);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_async_complete);
  
  /**
   * regmap_register_patch: Register and apply register updates to be applied
   *                        on device initialistion
   *
   * @map: Register map to apply updates to.
   * @regs: Values to update.
   * @num_regs: Number of entries in regs.
   *
   * Register a set of register updates to be applied to the device
   * whenever the device registers are synchronised with the cache and
   * apply them immediately.  Typically this is used to apply
   * corrections to be applied to the device defaults on startup, such
   * as the updates some vendors provide to undocumented registers.
   */
  int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
  			  int num_regs)
  {
  	int i, ret;
  	bool bypass;
  
  	/* If needed the implementation can be extended to support this */
  	if (map->patch)
  		return -EBUSY;
  
  	map->lock(map->lock_arg);
  
  	bypass = map->cache_bypass;
  
  	map->cache_bypass = true;
  
  	/* Write out first; it's useful to apply even if we fail later. */
  	for (i = 0; i < num_regs; i++) {
  		ret = _regmap_write(map, regs[i].reg, regs[i].def);
  		if (ret != 0) {
  			dev_err(map->dev, "Failed to write %x = %x: %d\n",
  				regs[i].reg, regs[i].def, ret);
  			goto out;
  		}
  	}
  
  	map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
  	if (map->patch != NULL) {
  		memcpy(map->patch, regs,
  		       num_regs * sizeof(struct reg_default));
  		map->patch_regs = num_regs;
  	} else {
  		ret = -ENOMEM;
  	}
  
  out:
  	map->cache_bypass = bypass;
  
  	map->unlock(map->lock_arg);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(regmap_register_patch);
  
  /*
   * regmap_get_val_bytes(): Report the size of a register value
   *
   * Report the size of a register value, mainly intended to for use by
   * generic infrastructure built on top of regmap.
   */
  int regmap_get_val_bytes(struct regmap *map)
  {
  	if (map->format.format_write)
  		return -EINVAL;
  
  	return map->format.val_bytes;
  }
  EXPORT_SYMBOL_GPL(regmap_get_val_bytes);
  
  static int __init regmap_initcall(void)
  {
  	regmap_debugfs_initcall();
  
  	return 0;
  }
  postcore_initcall(regmap_initcall);
  