| /* |
| * 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/slab.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/err.h> |
| |
| #define CREATE_TRACE_POINTS |
| #include <trace/events/regmap.h> |
| |
| #include "internal.h" |
| |
| 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->readable_reg) |
| return map->readable_reg(map->dev, reg); |
| |
| return true; |
| } |
| |
| bool regmap_volatile(struct regmap *map, unsigned int reg) |
| { |
| if (map->max_register && reg > map->max_register) |
| 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 (map->max_register && reg > map->max_register) |
| return false; |
| |
| if (map->precious_reg) |
| return map->precious_reg(map->dev, reg); |
| |
| return false; |
| } |
| |
| 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_8(void *buf, unsigned int val) |
| { |
| u8 *b = buf; |
| |
| b[0] = val; |
| } |
| |
| static void regmap_format_16(void *buf, unsigned int val) |
| { |
| __be16 *b = buf; |
| |
| b[0] = cpu_to_be16(val); |
| } |
| |
| static unsigned int regmap_parse_8(void *buf) |
| { |
| u8 *b = buf; |
| |
| return b[0]; |
| } |
| |
| static unsigned int regmap_parse_16(void *buf) |
| { |
| __be16 *b = buf; |
| |
| b[0] = be16_to_cpu(b[0]); |
| |
| return b[0]; |
| } |
| |
| /** |
| * regmap_init(): Initialise register map |
| * |
| * @dev: Device that will be interacted with |
| * @bus: Bus-specific callbacks to use with device |
| * @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, |
| const struct regmap_config *config) |
| { |
| struct regmap *map; |
| int ret = -EINVAL; |
| |
| if (!bus || !config) |
| return NULL; |
| |
| map = kzalloc(sizeof(*map), GFP_KERNEL); |
| if (map == NULL) { |
| ret = -ENOMEM; |
| goto err; |
| } |
| |
| mutex_init(&map->lock); |
| map->format.buf_size = (config->reg_bits + config->val_bits) / 8; |
| map->format.reg_bytes = config->reg_bits / 8; |
| map->format.val_bytes = config->val_bits / 8; |
| map->dev = dev; |
| map->bus = bus; |
| 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->reg_defaults = config->reg_defaults; |
| map->num_reg_defaults = config->num_reg_defaults; |
| map->num_reg_defaults_raw = config->num_reg_defaults_raw; |
| map->reg_defaults_raw = config->reg_defaults_raw; |
| map->cache_size_raw = (config->val_bits / 8) * config->num_reg_defaults_raw; |
| map->cache_word_size = config->val_bits / 8; |
| |
| 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; |
| } |
| |
| switch (config->reg_bits) { |
| 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 8: |
| map->format.format_reg = regmap_format_8; |
| break; |
| |
| case 16: |
| map->format.format_reg = regmap_format_16; |
| 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: |
| map->format.format_val = regmap_format_16; |
| map->format.parse_val = regmap_parse_16; |
| break; |
| } |
| |
| if (!map->format.format_write && |
| !(map->format.format_reg && map->format.format_val)) |
| goto err_map; |
| |
| map->work_buf = kmalloc(map->format.buf_size, GFP_KERNEL); |
| if (map->work_buf == NULL) { |
| ret = -ENOMEM; |
| goto err_map; |
| } |
| |
| ret = regcache_init(map); |
| if (ret < 0) |
| goto err_map; |
| |
| regmap_debugfs_init(map); |
| |
| return map; |
| |
| err_map: |
| kfree(map); |
| err: |
| return ERR_PTR(ret); |
| } |
| EXPORT_SYMBOL_GPL(regmap_init); |
| |
| /** |
| * regmap_exit(): Free a previously allocated register map |
| */ |
| void regmap_exit(struct regmap *map) |
| { |
| regcache_exit(map); |
| regmap_debugfs_exit(map); |
| kfree(map->work_buf); |
| kfree(map); |
| } |
| EXPORT_SYMBOL_GPL(regmap_exit); |
| |
| static int _regmap_raw_write(struct regmap *map, unsigned int reg, |
| const void *val, size_t val_len) |
| { |
| 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)) |
| return -EINVAL; |
| |
| map->format.format_reg(map->work_buf, reg); |
| |
| 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.reg_bytes) |
| ret = map->bus->write(map->dev, map->work_buf, |
| map->format.reg_bytes + val_len); |
| else if (map->bus->gather_write) |
| ret = map->bus->gather_write(map->dev, map->work_buf, |
| map->format.reg_bytes, |
| val, val_len); |
| |
| /* If that didn't work fall back on linearising by hand. */ |
| if (ret == -ENOTSUPP) { |
| len = map->format.reg_bytes + val_len; |
| buf = kmalloc(len, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| memcpy(buf, map->work_buf, map->format.reg_bytes); |
| memcpy(buf + map->format.reg_bytes, val, val_len); |
| ret = map->bus->write(map->dev, 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) |
| { |
| int ret; |
| BUG_ON(!map->format.format_write && !map->format.format_val); |
| |
| if (!map->cache_bypass) { |
| ret = regcache_write(map, reg, val); |
| if (ret != 0) |
| return ret; |
| if (map->cache_only) { |
| map->cache_dirty = true; |
| return 0; |
| } |
| } |
| |
| trace_regmap_reg_write(map->dev, reg, val); |
| |
| if (map->format.format_write) { |
| map->format.format_write(map, reg, val); |
| |
| trace_regmap_hw_write_start(map->dev, reg, 1); |
| |
| ret = map->bus->write(map->dev, 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, |
| val); |
| return _regmap_raw_write(map, reg, |
| map->work_buf + map->format.reg_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; |
| |
| mutex_lock(&map->lock); |
| |
| ret = _regmap_write(map, reg, val); |
| |
| mutex_unlock(&map->lock); |
| |
| 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; |
| |
| WARN_ON(map->cache_type != REGCACHE_NONE); |
| |
| mutex_lock(&map->lock); |
| |
| ret = _regmap_raw_write(map, reg, val, val_len); |
| |
| mutex_unlock(&map->lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(regmap_raw_write); |
| |
| static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val, |
| unsigned int val_len) |
| { |
| u8 *u8 = map->work_buf; |
| int ret; |
| |
| map->format.format_reg(map->work_buf, reg); |
| |
| /* |
| * 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->dev, map->work_buf, map->format.reg_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->format.parse_val) |
| return -EINVAL; |
| |
| if (!map->cache_bypass) { |
| ret = regcache_read(map, reg, val); |
| if (ret == 0) |
| return 0; |
| } |
| |
| 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); |
| trace_regmap_reg_read(map->dev, 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; |
| |
| mutex_lock(&map->lock); |
| |
| ret = _regmap_read(map, reg, val); |
| |
| mutex_unlock(&map->lock); |
| |
| 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) |
| { |
| int ret; |
| int i; |
| bool vol = true; |
| |
| for (i = 0; i < val_len / map->format.val_bytes; i++) |
| if (!regmap_volatile(map, reg + i)) |
| vol = false; |
| |
| WARN_ON(!vol && map->cache_type != REGCACHE_NONE); |
| |
| mutex_lock(&map->lock); |
| |
| ret = _regmap_raw_read(map, reg, val, val_len); |
| |
| mutex_unlock(&map->lock); |
| |
| 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 = true; |
| |
| if (!map->format.parse_val) |
| return -EINVAL; |
| |
| /* Is this a block of volatile registers? */ |
| for (i = 0; i < val_count; i++) |
| if (!regmap_volatile(map, reg + i)) |
| vol = false; |
| |
| if (vol || map->cache_type == REGCACHE_NONE) { |
| 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++) { |
| ret = regmap_read(map, reg + i, val + (i * val_bytes)); |
| if (ret != 0) |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(regmap_bulk_read); |
| |
| /** |
| * remap_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) |
| { |
| int ret; |
| unsigned int tmp; |
| |
| mutex_lock(&map->lock); |
| |
| ret = _regmap_read(map, reg, &tmp); |
| if (ret != 0) |
| goto out; |
| |
| tmp &= ~mask; |
| tmp |= val & mask; |
| |
| ret = _regmap_write(map, reg, tmp); |
| |
| out: |
| mutex_unlock(&map->lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(regmap_update_bits); |
| |
| static int __init regmap_initcall(void) |
| { |
| regmap_debugfs_initcall(); |
| |
| return 0; |
| } |
| postcore_initcall(regmap_initcall); |