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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/base/regmap/regmap-i2c.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/base/regmap/regmap-i2c.c')
-rw-r--r-- | drivers/base/regmap/regmap-i2c.c | 399 |
1 files changed, 399 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-i2c.c b/drivers/base/regmap/regmap-i2c.c new file mode 100644 index 000000000..3ec611dc0 --- /dev/null +++ b/drivers/base/regmap/regmap-i2c.c @@ -0,0 +1,399 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Register map access API - I2C support +// +// Copyright 2011 Wolfson Microelectronics plc +// +// Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + +#include <linux/regmap.h> +#include <linux/i2c.h> +#include <linux/module.h> + +#include "internal.h" + +static int regmap_smbus_byte_reg_read(void *context, unsigned int reg, + unsigned int *val) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + int ret; + + if (reg > 0xff) + return -EINVAL; + + ret = i2c_smbus_read_byte_data(i2c, reg); + if (ret < 0) + return ret; + + *val = ret; + + return 0; +} + +static int regmap_smbus_byte_reg_write(void *context, unsigned int reg, + unsigned int val) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + + if (val > 0xff || reg > 0xff) + return -EINVAL; + + return i2c_smbus_write_byte_data(i2c, reg, val); +} + +static const struct regmap_bus regmap_smbus_byte = { + .reg_write = regmap_smbus_byte_reg_write, + .reg_read = regmap_smbus_byte_reg_read, +}; + +static int regmap_smbus_word_reg_read(void *context, unsigned int reg, + unsigned int *val) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + int ret; + + if (reg > 0xff) + return -EINVAL; + + ret = i2c_smbus_read_word_data(i2c, reg); + if (ret < 0) + return ret; + + *val = ret; + + return 0; +} + +static int regmap_smbus_word_reg_write(void *context, unsigned int reg, + unsigned int val) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + + if (val > 0xffff || reg > 0xff) + return -EINVAL; + + return i2c_smbus_write_word_data(i2c, reg, val); +} + +static const struct regmap_bus regmap_smbus_word = { + .reg_write = regmap_smbus_word_reg_write, + .reg_read = regmap_smbus_word_reg_read, +}; + +static int regmap_smbus_word_read_swapped(void *context, unsigned int reg, + unsigned int *val) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + int ret; + + if (reg > 0xff) + return -EINVAL; + + ret = i2c_smbus_read_word_swapped(i2c, reg); + if (ret < 0) + return ret; + + *val = ret; + + return 0; +} + +static int regmap_smbus_word_write_swapped(void *context, unsigned int reg, + unsigned int val) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + + if (val > 0xffff || reg > 0xff) + return -EINVAL; + + return i2c_smbus_write_word_swapped(i2c, reg, val); +} + +static const struct regmap_bus regmap_smbus_word_swapped = { + .reg_write = regmap_smbus_word_write_swapped, + .reg_read = regmap_smbus_word_read_swapped, +}; + +static int regmap_i2c_write(void *context, const void *data, size_t count) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + int ret; + + ret = i2c_master_send(i2c, data, count); + if (ret == count) + return 0; + else if (ret < 0) + return ret; + else + return -EIO; +} + +static int regmap_i2c_gather_write(void *context, + const void *reg, size_t reg_size, + const void *val, size_t val_size) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + struct i2c_msg xfer[2]; + int ret; + + /* If the I2C controller can't do a gather tell the core, it + * will substitute in a linear write for us. + */ + if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_NOSTART)) + return -ENOTSUPP; + + xfer[0].addr = i2c->addr; + xfer[0].flags = 0; + xfer[0].len = reg_size; + xfer[0].buf = (void *)reg; + + xfer[1].addr = i2c->addr; + xfer[1].flags = I2C_M_NOSTART; + xfer[1].len = val_size; + xfer[1].buf = (void *)val; + + ret = i2c_transfer(i2c->adapter, xfer, 2); + if (ret == 2) + return 0; + if (ret < 0) + return ret; + else + return -EIO; +} + +static int regmap_i2c_read(void *context, + const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + struct i2c_msg xfer[2]; + int ret; + + xfer[0].addr = i2c->addr; + xfer[0].flags = 0; + xfer[0].len = reg_size; + xfer[0].buf = (void *)reg; + + xfer[1].addr = i2c->addr; + xfer[1].flags = I2C_M_RD; + xfer[1].len = val_size; + xfer[1].buf = val; + + ret = i2c_transfer(i2c->adapter, xfer, 2); + if (ret == 2) + return 0; + else if (ret < 0) + return ret; + else + return -EIO; +} + +static const struct regmap_bus regmap_i2c = { + .write = regmap_i2c_write, + .gather_write = regmap_i2c_gather_write, + .read = regmap_i2c_read, + .reg_format_endian_default = REGMAP_ENDIAN_BIG, + .val_format_endian_default = REGMAP_ENDIAN_BIG, +}; + +static int regmap_i2c_smbus_i2c_write(void *context, const void *data, + size_t count) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + + if (count < 1) + return -EINVAL; + + --count; + return i2c_smbus_write_i2c_block_data(i2c, ((u8 *)data)[0], count, + ((u8 *)data + 1)); +} + +static int regmap_i2c_smbus_i2c_read(void *context, const void *reg, + size_t reg_size, void *val, + size_t val_size) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + int ret; + + if (reg_size != 1 || val_size < 1) + return -EINVAL; + + ret = i2c_smbus_read_i2c_block_data(i2c, ((u8 *)reg)[0], val_size, val); + if (ret == val_size) + return 0; + else if (ret < 0) + return ret; + else + return -EIO; +} + +static const struct regmap_bus regmap_i2c_smbus_i2c_block = { + .write = regmap_i2c_smbus_i2c_write, + .read = regmap_i2c_smbus_i2c_read, + .max_raw_read = I2C_SMBUS_BLOCK_MAX - 1, + .max_raw_write = I2C_SMBUS_BLOCK_MAX - 1, +}; + +static int regmap_i2c_smbus_i2c_write_reg16(void *context, const void *data, + size_t count) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + + if (count < 2) + return -EINVAL; + + count--; + return i2c_smbus_write_i2c_block_data(i2c, ((u8 *)data)[0], count, + (u8 *)data + 1); +} + +static int regmap_i2c_smbus_i2c_read_reg16(void *context, const void *reg, + size_t reg_size, void *val, + size_t val_size) +{ + struct device *dev = context; + struct i2c_client *i2c = to_i2c_client(dev); + int ret, count, len = val_size; + + if (reg_size != 2) + return -EINVAL; + + ret = i2c_smbus_write_byte_data(i2c, ((u16 *)reg)[0] & 0xff, + ((u16 *)reg)[0] >> 8); + if (ret < 0) + return ret; + + count = 0; + do { + /* Current Address Read */ + ret = i2c_smbus_read_byte(i2c); + if (ret < 0) + break; + + *((u8 *)val++) = ret; + count++; + len--; + } while (len > 0); + + if (count == val_size) + return 0; + else if (ret < 0) + return ret; + else + return -EIO; +} + +static const struct regmap_bus regmap_i2c_smbus_i2c_block_reg16 = { + .write = regmap_i2c_smbus_i2c_write_reg16, + .read = regmap_i2c_smbus_i2c_read_reg16, + .max_raw_read = I2C_SMBUS_BLOCK_MAX - 2, + .max_raw_write = I2C_SMBUS_BLOCK_MAX - 2, +}; + +static const struct regmap_bus *regmap_get_i2c_bus(struct i2c_client *i2c, + const struct regmap_config *config) +{ + const struct i2c_adapter_quirks *quirks; + const struct regmap_bus *bus = NULL; + struct regmap_bus *ret_bus; + u16 max_read = 0, max_write = 0; + + if (i2c_check_functionality(i2c->adapter, I2C_FUNC_I2C)) + bus = ®map_i2c; + else if (config->val_bits == 8 && config->reg_bits == 8 && + i2c_check_functionality(i2c->adapter, + I2C_FUNC_SMBUS_I2C_BLOCK)) + bus = ®map_i2c_smbus_i2c_block; + else if (config->val_bits == 8 && config->reg_bits == 16 && + i2c_check_functionality(i2c->adapter, + I2C_FUNC_SMBUS_I2C_BLOCK)) + bus = ®map_i2c_smbus_i2c_block_reg16; + else if (config->val_bits == 16 && config->reg_bits == 8 && + i2c_check_functionality(i2c->adapter, + I2C_FUNC_SMBUS_WORD_DATA)) + switch (regmap_get_val_endian(&i2c->dev, NULL, config)) { + case REGMAP_ENDIAN_LITTLE: + bus = ®map_smbus_word; + break; + case REGMAP_ENDIAN_BIG: + bus = ®map_smbus_word_swapped; + break; + default: /* everything else is not supported */ + break; + } + else if (config->val_bits == 8 && config->reg_bits == 8 && + i2c_check_functionality(i2c->adapter, + I2C_FUNC_SMBUS_BYTE_DATA)) + bus = ®map_smbus_byte; + + if (!bus) + return ERR_PTR(-ENOTSUPP); + + quirks = i2c->adapter->quirks; + if (quirks) { + if (quirks->max_read_len && + (bus->max_raw_read == 0 || bus->max_raw_read > quirks->max_read_len)) + max_read = quirks->max_read_len; + + if (quirks->max_write_len && + (bus->max_raw_write == 0 || bus->max_raw_write > quirks->max_write_len)) + max_write = quirks->max_write_len; + + if (max_read || max_write) { + ret_bus = kmemdup(bus, sizeof(*bus), GFP_KERNEL); + if (!ret_bus) + return ERR_PTR(-ENOMEM); + ret_bus->free_on_exit = true; + ret_bus->max_raw_read = max_read; + ret_bus->max_raw_write = max_write; + bus = ret_bus; + } + } + + return bus; +} + +struct regmap *__regmap_init_i2c(struct i2c_client *i2c, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + const struct regmap_bus *bus = regmap_get_i2c_bus(i2c, config); + + if (IS_ERR(bus)) + return ERR_CAST(bus); + + return __regmap_init(&i2c->dev, bus, &i2c->dev, config, + lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__regmap_init_i2c); + +struct regmap *__devm_regmap_init_i2c(struct i2c_client *i2c, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + const struct regmap_bus *bus = regmap_get_i2c_bus(i2c, config); + + if (IS_ERR(bus)) + return ERR_CAST(bus); + + return __devm_regmap_init(&i2c->dev, bus, &i2c->dev, config, + lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__devm_regmap_init_i2c); + +MODULE_LICENSE("GPL"); |