regmap.c

/**
 * regmap_update_bits_async: Perform a read/modify/write cycle on the register
 *                           map asynchronously
 *
 * @map: Register map to update
 * @reg: Register to update
 * @mask: Bitmask to change
 * @val: New value for bitmask
 *
 * With most buses the read must be done synchronously so this is most
 * useful for devices with a cache which do not need to interact with
 * the hardware to determine the current register value.
 *
 * Returns zero for success, a negative number on error.
 */
int regmap_update_bits_async(struct regmap *map, unsigned int reg,
			     unsigned int mask, unsigned int val)
{
	bool change;
	int ret;

	map->lock(map->lock_arg);

	map->async = true;

	ret = _regmap_update_bits(map, reg, mask, val, &change);

	map->async = false;

	map->unlock(map->lock_arg);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_update_bits_async);

/**
 * 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);

/**
 * regmap_update_bits_check_async: Perform a read/modify/write cycle on the
 *                                 register map asynchronously 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
 *
 * With most buses the read must be done synchronously so this is most
 * useful for devices with a cache which do not need to interact with
 * the hardware to determine the current register value.
 *
 * Returns zero for success, a negative number on error.
 */
int regmap_update_bits_check_async(struct regmap *map, unsigned int reg,
				   unsigned int mask, unsigned int val,
				   bool *change)
{
	int ret;

	map->lock(map->lock_arg);

	map->async = true;

	ret = _regmap_update_bits(map, reg, mask, val, change);

	map->async = false;

	map->unlock(map->lock_arg);

	return ret;
}
EXPORT_SYMBOL_GPL(regmap_update_bits_check_async);

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_move(&async->list, &map->async_free);
	wake = list_empty(&map->async_list);

	if (ret != 0)
		map->async_ret = ret;

	spin_unlock(&map->async_lock);

	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)
{
	struct reg_default *p;
	int i, ret;
	bool bypass;

	if (WARN_ONCE(num_regs <= 0, "invalid registers number (%d)\n",
	    num_regs))
		return 0;

	map->lock(map->lock_arg);

	bypass = map->cache_bypass;

	map->cache_bypass = true;
	map->async = 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;
		}
	}

	p = krealloc(map->patch,
		     sizeof(struct reg_default) * (map->patch_regs + num_regs),
		     GFP_KERNEL);
	if (p) {
		memcpy(p + map->patch_regs, regs, num_regs * sizeof(*regs));
		map->patch = p;
		map->patch_regs += num_regs;
	} else {
		ret = -ENOMEM;
	}

out:
	map->async = false;
	map->cache_bypass = bypass;

	map->unlock(map->lock_arg);

	regmap_async_complete(map);

	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);