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kernel-hacking-2024-linux-s.../drivers/base/regmap/regmap.c
Mark Brown 0ff3e62ff1 regmap: Make return code checks consistent 
The range code was written to check for return codes less than zero as
errors but throughout the rest of the API return codes not equal to zero
are errors. Change all these checks to match the house style.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-10-15 10:00:00 +09:00

1453 lines
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/*
* 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>
#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);
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);
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);
return true;
}
bool regmap_volatile(struct regmap *map, unsigned int reg)
{
if (!regmap_readable(map, reg))
return false;
if (map->volatile_reg)
return map->volatile_reg(map->dev, reg);
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);
return false;
}
static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
unsigned int 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 unsigned int regmap_parse_8(void *buf)
{
u8 *b = buf;
return b[0];
}
static unsigned int regmap_parse_16_be(void *buf)
{
__be16 *b = buf;
b[0] = be16_to_cpu(b[0]);
return b[0];
}
static unsigned int regmap_parse_16_native(void *buf)
{
return *(u16 *)buf;
}
static unsigned int regmap_parse_24(void *buf)
{
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(void *buf)
{
__be32 *b = buf;
b[0] = be32_to_cpu(b[0]);
return b[0];
}
static unsigned int regmap_parse_32_native(void *buf)
{
return *(u32 *)buf;
}
static void regmap_lock_mutex(struct regmap *map)
{
mutex_lock(&map->mutex);
}
static void regmap_unlock_mutex(struct regmap *map)
{
mutex_unlock(&map->mutex);
}
static void regmap_lock_spinlock(struct regmap *map)
{
spin_lock(&map->spinlock);
}
static void regmap_unlock_spinlock(struct regmap *map)
{
spin_unlock(&map->spinlock);
}
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 (!bus || !config)
goto err;
map = kzalloc(sizeof(*map), GFP_KERNEL);
if (map == NULL) {
ret = -ENOMEM;
goto err;
}
if (bus->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->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->writeable_reg = config->writeable_reg;
map->readable_reg = config->readable_reg;
map->volatile_reg = config->volatile_reg;
map->precious_reg = config->precious_reg;
map->cache_type = config->cache_type;
map->name = config->name;
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 {
map->read_flag_mask = bus->read_flag_mask;
}
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 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;
}
switch (config->val_bits) {
case 8:
map->format.format_val = regmap_format_8;
map->format.parse_val = regmap_parse_8;
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;
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;
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;
}
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;
}
}
}
ret = regcache_init(map, config);
if (ret != 0)
goto err_range;
regmap_debugfs_init(map, config->name);
/* 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->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->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;
}
static int _regmap_raw_write(struct regmap *map, unsigned int reg,
const void *val, size_t val_len)
{
struct regmap_range_node *range;
u8 *u8 = map->work_buf;
void *buf;
int ret = -ENOTSUPP;
size_t len;
int i;
/* 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++) {
memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
ival = map->format.parse_val(map->work_buf);
ret = regcache_write(map, reg + (i * map->reg_stride),
ival);
if (ret) {
dev_err(map->dev,
"Error in caching of register: %u 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) {
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);
u8[0] |= map->write_flag_mask;
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 == (map->work_buf + map->format.pad_bytes +
map->format.reg_bytes))
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;
}
int _regmap_write(struct regmap *map, unsigned int reg,
unsigned int val)
{
struct regmap_range_node *range;
int ret;
BUG_ON(!map->format.format_write && !map->format.format_val);
if (!map->cache_bypass && map->format.format_write) {
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 (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);
if (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;
} else {
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);
}
}
/**
* 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);
ret = _regmap_write(map, reg, val);
map->unlock(map);
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 (val_len % map->format.val_bytes)
return -EINVAL;
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
ret = _regmap_raw_write(map, reg, val, val_len);
map->unlock(map);
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 be 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->format.parse_val)
return -EINVAL;
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
/* 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_val(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);
}
if (val_bytes != 1)
kfree(wval);
out:
map->unlock(map);
return ret;
}
EXPORT_SYMBOL_GPL(regmap_bulk_write);
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;
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_read(struct regmap *map, unsigned int reg,
unsigned int *val)
{
int ret;
if (!map->cache_bypass) {
ret = regcache_read(map, reg, val);
if (ret == 0)
return 0;
}
if (!map->format.parse_val)
return -EINVAL;
if (map->cache_only)
return -EBUSY;
ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
if (ret == 0) {
*val = map->format.parse_val(map->work_buf);
#ifdef LOG_DEVICE
if (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 (ret == 0 && !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);
ret = _regmap_read(map, reg, val);
map->unlock(map);
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 (val_len % map->format.val_bytes)
return -EINVAL;
if (reg % map->reg_stride)
return -EINVAL;
map->lock(map);
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);
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->format.parse_val)
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_val(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;
memcpy(val + (i * val_bytes), &ival, val_bytes);
}
}
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);
ret = _regmap_update_bits(map, reg, mask, val, &change);
map->unlock(map);
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);
ret = _regmap_update_bits(map, reg, mask, val, change);
map->unlock(map);
return ret;
}
EXPORT_SYMBOL_GPL(regmap_update_bits_check);
/**
* 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);
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);
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);
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