[linux-2.6-block.git] / drivers / base / regmap / regcache.c

/*
 * Register cache access API
 *
 * Copyright 2011 Wolfson Microelectronics plc
 *
 * Author: Dimitris Papastamos <dp@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/slab.h>
#include <trace/events/regmap.h>

#include "internal.h"

static const struct regcache_ops *cache_types[] = {
	&regcache_indexed_ops,
	&regcache_rbtree_ops,
};

static int regcache_hw_init(struct regmap *map)
{
	int i, j;
	int ret;
	int count;
	unsigned int val;
	void *tmp_buf;

	if (!map->num_reg_defaults_raw)
		return -EINVAL;

	if (!map->reg_defaults_raw) {
		dev_warn(map->dev, "No cache defaults, reading back from HW\n");
		tmp_buf = kmalloc(map->cache_size_raw, GFP_KERNEL);
		if (!tmp_buf)
			return -EINVAL;
		ret = regmap_bulk_read(map, 0, tmp_buf,
				       map->num_reg_defaults_raw);
		if (ret < 0) {
			kfree(tmp_buf);
			return ret;
		}
		map->reg_defaults_raw = tmp_buf;
		map->cache_free = 1;
	}

	/* calculate the size of reg_defaults */
	for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++) {
		val = regcache_get_val(map->reg_defaults_raw,
				       i, map->cache_word_size);
		if (!val)
			continue;
		count++;
	}

	map->reg_defaults = kmalloc(count * sizeof(struct reg_default),
				      GFP_KERNEL);
	if (!map->reg_defaults)
		return -ENOMEM;

	/* fill the reg_defaults */
	map->num_reg_defaults = count;
	for (i = 0, j = 0; i < map->num_reg_defaults_raw; i++) {
		val = regcache_get_val(map->reg_defaults_raw,
				       i, map->cache_word_size);
		if (!val)
			continue;
		map->reg_defaults[j].reg = i;
		map->reg_defaults[j].def = val;
		j++;
	}

	return 0;
}

int regcache_init(struct regmap *map)
{
	int ret;
	int i;
	void *tmp_buf;

	if (map->cache_type == REGCACHE_NONE)
		return 0;

	for (i = 0; i < ARRAY_SIZE(cache_types); i++)
		if (cache_types[i]->type == map->cache_type)
			break;

	if (i == ARRAY_SIZE(cache_types)) {
		dev_err(map->dev, "Could not match compress type: %d\n",
			map->cache_type);
		return -EINVAL;
	}

	map->cache = NULL;
	map->cache_ops = cache_types[i];

	if (!map->cache_ops->read ||
	    !map->cache_ops->write ||
	    !map->cache_ops->name)
		return -EINVAL;

	/* We still need to ensure that the reg_defaults
	 * won't vanish from under us.  We'll need to make
	 * a copy of it.
	 */
	if (map->reg_defaults) {
		if (!map->num_reg_defaults)
			return -EINVAL;
		tmp_buf = kmemdup(map->reg_defaults, map->num_reg_defaults *
				  sizeof(struct reg_default), GFP_KERNEL);
		if (!tmp_buf)
			return -ENOMEM;
		map->reg_defaults = tmp_buf;
	} else {
		/* Some devices such as PMIC's don't have cache defaults,
		 * we cope with this by reading back the HW registers and
		 * crafting the cache defaults by hand.
		 */
		ret = regcache_hw_init(map);
		if (ret < 0)
			return ret;
	}

	if (!map->max_register)
		map->max_register = map->num_reg_defaults_raw;

	if (map->cache_ops->init) {
		dev_dbg(map->dev, "Initializing %s cache\n",
			map->cache_ops->name);
		return map->cache_ops->init(map);
	}
	return 0;
}

void regcache_exit(struct regmap *map)
{
	if (map->cache_type == REGCACHE_NONE)
		return;

	BUG_ON(!map->cache_ops);

	kfree(map->reg_defaults);
	if (map->cache_free)
		kfree(map->reg_defaults_raw);

	if (map->cache_ops->exit) {
		dev_dbg(map->dev, "Destroying %s cache\n",
			map->cache_ops->name);
		map->cache_ops->exit(map);
	}
}

/**
 * regcache_read: Fetch the value of a given register from the cache.
 *
 * @map: map to configure.
 * @reg: The register index.
 * @value: The value to be returned.
 *
 * Return a negative value on failure, 0 on success.
 */
int regcache_read(struct regmap *map,
		  unsigned int reg, unsigned int *value)
{
	if (map->cache_type == REGCACHE_NONE)
		return -ENOSYS;

	BUG_ON(!map->cache_ops);

	if (!regmap_readable(map, reg))
		return -EIO;

	if (!regmap_volatile(map, reg))
		return map->cache_ops->read(map, reg, value);

	return -EINVAL;
}
EXPORT_SYMBOL_GPL(regcache_read);

/**
 * regcache_write: Set the value of a given register in the cache.
 *
 * @map: map to configure.
 * @reg: The register index.
 * @value: The new register value.
 *
 * Return a negative value on failure, 0 on success.
 */
int regcache_write(struct regmap *map,
		   unsigned int reg, unsigned int value)
{
	if (map->cache_type == REGCACHE_NONE)
		return 0;

	BUG_ON(!map->cache_ops);

	if (!regmap_writeable(map, reg))
		return -EIO;

	if (!regmap_volatile(map, reg))
		return map->cache_ops->write(map, reg, value);

	return 0;
}
EXPORT_SYMBOL_GPL(regcache_write);

/**
 * regcache_sync: Sync the register cache with the hardware.
 *
 * @map: map to configure.
 *
 * Any registers that should not be synced should be marked as
 * volatile.  In general drivers can choose not to use the provided
 * syncing functionality if they so require.
 *
 * Return a negative value on failure, 0 on success.
 */
int regcache_sync(struct regmap *map)
{
	BUG_ON(!map->cache_ops);

	if (map->cache_ops->sync) {
		dev_dbg(map->dev, "Syncing %s cache\n",
			map->cache_ops->name);
		return map->cache_ops->sync(map);
	}
	return 0;
}
EXPORT_SYMBOL_GPL(regcache_sync);

bool regcache_set_val(void *base, unsigned int idx,
		      unsigned int val, unsigned int word_size)
{
	switch (word_size) {
	case 1: {
		u8 *cache = base;
		if (cache[idx] == val)
			return true;
		cache[idx] = val;
		break;
	}
	case 2: {
		u16 *cache = base;
		if (cache[idx] == val)
			return true;
		cache[idx] = val;
		break;
	}
	default:
		BUG();
	}
	/* unreachable */
	return false;
}

unsigned int regcache_get_val(const void *base, unsigned int idx,
			      unsigned int word_size)
{
	if (!base)
		return -EINVAL;

	switch (word_size) {
	case 1: {
		const u8 *cache = base;
		return cache[idx];
	}
	case 2: {
		const u16 *cache = base;
		return cache[idx];
	}
	default:
		BUG();
	}
	/* unreachable */
	return -1;
}

int regcache_lookup_reg(struct regmap *map, unsigned int reg)
{
	unsigned int i;

	for (i = 0; i < map->num_reg_defaults; i++)
		if (map->reg_defaults[i].reg == reg)
			return i;
	return -1;
}

int regcache_insert_reg(struct regmap *map, unsigned int reg,
			unsigned int val)
{
	void *tmp;

	tmp = krealloc(map->reg_defaults,
		       (map->num_reg_defaults + 1) * sizeof(struct reg_default),
		       GFP_KERNEL);
	if (!tmp)
		return -ENOMEM;
	map->reg_defaults = tmp;
	map->num_reg_defaults++;
	map->reg_defaults[map->num_reg_defaults - 1].reg = reg;
	map->reg_defaults[map->num_reg_defaults - 1].def = val;
	return 0;
}
Commit	Line	Data
9fabe24e DP	1	/*
	2	* Register cache access API
	3	*
	4	* Copyright 2011 Wolfson Microelectronics plc
	5	*
	6	* Author: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/slab.h>
	14	#include <trace/events/regmap.h>
	15
	16	#include "internal.h"
	17
	18	static const struct regcache_ops *cache_types[] = {
195af65c	19	&regcache_indexed_ops,
28644c80	20	&regcache_rbtree_ops,
9fabe24e DP	21	};
	22
	23	static int regcache_hw_init(struct regmap *map)
	24	{
	25	int i, j;
	26	int ret;
	27	int count;
	28	unsigned int val;
	29	void *tmp_buf;
	30
	31	if (!map->num_reg_defaults_raw)
	32	return -EINVAL;
	33
	34	if (!map->reg_defaults_raw) {
	35	dev_warn(map->dev, "No cache defaults, reading back from HW\n");
	36	tmp_buf = kmalloc(map->cache_size_raw, GFP_KERNEL);
	37	if (!tmp_buf)
	38	return -EINVAL;
	39	ret = regmap_bulk_read(map, 0, tmp_buf,
	40	map->num_reg_defaults_raw);
	41	if (ret < 0) {
	42	kfree(tmp_buf);
	43	return ret;
	44	}
	45	map->reg_defaults_raw = tmp_buf;
	46	map->cache_free = 1;
	47	}
	48
	49	/* calculate the size of reg_defaults */
	50	for (count = 0, i = 0; i < map->num_reg_defaults_raw; i++) {
	51	val = regcache_get_val(map->reg_defaults_raw,
	52	i, map->cache_word_size);
	53	if (!val)
	54	continue;
	55	count++;
	56	}
	57
	58	map->reg_defaults = kmalloc(count * sizeof(struct reg_default),
	59	GFP_KERNEL);
	60	if (!map->reg_defaults)
	61	return -ENOMEM;
	62
	63	/* fill the reg_defaults */
	64	map->num_reg_defaults = count;
	65	for (i = 0, j = 0; i < map->num_reg_defaults_raw; i++) {
	66	val = regcache_get_val(map->reg_defaults_raw,
	67	i, map->cache_word_size);
	68	if (!val)
	69	continue;
	70	map->reg_defaults[j].reg = i;
	71	map->reg_defaults[j].def = val;
	72	j++;
	73	}
	74
	75	return 0;
	76	}
	77
	78	int regcache_init(struct regmap *map)
	79	{
	80	int ret;
	81	int i;
	82	void *tmp_buf;
	83
	84	if (map->cache_type == REGCACHE_NONE)
85	return 0;
86
87	for (i = 0; i < ARRAY_SIZE(cache_types); i++)
88	if (cache_types[i]->type == map->cache_type)
89	break;
90
91	if (i == ARRAY_SIZE(cache_types)) {
92	dev_err(map->dev, "Could not match compress type: %d\n",
93	map->cache_type);
94	return -EINVAL;
95	}
96
97	map->cache = NULL;
98	map->cache_ops = cache_types[i];
99
100	if (!map->cache_ops->read \|\|
101	!map->cache_ops->write \|\|
102	!map->cache_ops->name)
103	return -EINVAL;
104
105	/* We still need to ensure that the reg_defaults
106	* won't vanish from under us. We'll need to make
107	* a copy of it.
108	*/
109	if (map->reg_defaults) {
110	if (!map->num_reg_defaults)
111	return -EINVAL;
112	tmp_buf = kmemdup(map->reg_defaults, map->num_reg_defaults *
113	sizeof(struct reg_default), GFP_KERNEL);
114	if (!tmp_buf)
115	return -ENOMEM;
116	map->reg_defaults = tmp_buf;
117	} else {
118	/* Some devices such as PMIC's don't have cache defaults,
119	* we cope with this by reading back the HW registers and
120	* crafting the cache defaults by hand.
121	*/
122	ret = regcache_hw_init(map);
123	if (ret < 0)
124	return ret;
125	}
126
127	if (!map->max_register)
128	map->max_register = map->num_reg_defaults_raw;
129
130	if (map->cache_ops->init) {
131	dev_dbg(map->dev, "Initializing %s cache\n",
132	map->cache_ops->name);
133	return map->cache_ops->init(map);
134	}
135	return 0;
136	}
137
138	void regcache_exit(struct regmap *map)
139	{
140	if (map->cache_type == REGCACHE_NONE)
141	return;
142
143	BUG_ON(!map->cache_ops);
144
145	kfree(map->reg_defaults);
146	if (map->cache_free)
147	kfree(map->reg_defaults_raw);
148
149	if (map->cache_ops->exit) {
150	dev_dbg(map->dev, "Destroying %s cache\n",
151	map->cache_ops->name);
152	map->cache_ops->exit(map);
153	}
154	}
155
156	/**
157	* regcache_read: Fetch the value of a given register from the cache.
158	*
159	* @map: map to configure.
160	* @reg: The register index.
161	* @value: The value to be returned.
162	*
163	* Return a negative value on failure, 0 on success.
164	*/
165	int regcache_read(struct regmap *map,
166	unsigned int reg, unsigned int *value)
167	{
168	if (map->cache_type == REGCACHE_NONE)
169	return -ENOSYS;
170
171	BUG_ON(!map->cache_ops);
172
173	if (!regmap_readable(map, reg))
174	return -EIO;
175
176	if (!regmap_volatile(map, reg))
177	return map->cache_ops->read(map, reg, value);
178
179	return -EINVAL;
180	}
181	EXPORT_SYMBOL_GPL(regcache_read);
182
183	/**
184	* regcache_write: Set the value of a given register in the cache.
185	*
186	* @map: map to configure.
187	* @reg: The register index.
188	* @value: The new register value.
189	*
190	* Return a negative value on failure, 0 on success.
191	*/
192	int regcache_write(struct regmap *map,
193	unsigned int reg, unsigned int value)
194	{
195	if (map->cache_type == REGCACHE_NONE)
196	return 0;
197
198	BUG_ON(!map->cache_ops);
199
200	if (!regmap_writeable(map, reg))
201	return -EIO;
202
203	if (!regmap_volatile(map, reg))
204	return map->cache_ops->write(map, reg, value);
205
206	return 0;
207	}
208	EXPORT_SYMBOL_GPL(regcache_write);
209
210	/**
211	* regcache_sync: Sync the register cache with the hardware.
212	*
213	* @map: map to configure.
214	*
215	* Any registers that should not be synced should be marked as
216	* volatile. In general drivers can choose not to use the provided
217	* syncing functionality if they so require.
218	*
219	* Return a negative value on failure, 0 on success.
220	*/
221	int regcache_sync(struct regmap *map)
222	{
223	BUG_ON(!map->cache_ops);
224
225	if (map->cache_ops->sync) {
226	dev_dbg(map->dev, "Syncing %s cache\n",
227	map->cache_ops->name);
228	return map->cache_ops->sync(map);
229	}
230	return 0;
231	}
232	EXPORT_SYMBOL_GPL(regcache_sync);
233
234	bool regcache_set_val(void *base, unsigned int idx,
235	unsigned int val, unsigned int word_size)
236	{
237	switch (word_size) {
238	case 1: {
239	u8 *cache = base;
240	if (cache[idx] == val)
241	return true;
242	cache[idx] = val;
243	break;
244	}
245	case 2: {
246	u16 *cache = base;
247	if (cache[idx] == val)
248	return true;
249	cache[idx] = val;
250	break;
251	}
252	default:
253	BUG();
254	}
255	/* unreachable */
256	return false;
257	}
258
259	unsigned int regcache_get_val(const void *base, unsigned int idx,
260	unsigned int word_size)
261	{
262	if (!base)
263	return -EINVAL;
264
265	switch (word_size) {
266	case 1: {
267	const u8 *cache = base;
268	return cache[idx];
269	}
270	case 2: {
271	const u16 *cache = base;
272	return cache[idx];
273	}
274	default:
275	BUG();
276	}
277	/* unreachable */
278	return -1;
279	}
280
281	int regcache_lookup_reg(struct regmap *map, unsigned int reg)
282	{
283	unsigned int i;
284
285	for (i = 0; i < map->num_reg_defaults; i++)
286	if (map->reg_defaults[i].reg == reg)
287	return i;
288	return -1;
289	}
290
291	int regcache_insert_reg(struct regmap *map, unsigned int reg,
292	unsigned int val)
293	{
294	void *tmp;
295
296	tmp = krealloc(map->reg_defaults,
297	(map->num_reg_defaults + 1) * sizeof(struct reg_default),
298	GFP_KERNEL);
299	if (!tmp)
300	return -ENOMEM;
301	map->reg_defaults = tmp;
302	map->num_reg_defaults++;
303	map->reg_defaults[map->num_reg_defaults - 1].reg = reg;
304	map->reg_defaults[map->num_reg_defaults - 1].def = val;
305	return 0;
306	}