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path: root/drivers/base/regmap/regmap-i2c.c
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Diffstat (limited to 'drivers/base/regmap/regmap-i2c.c')
-rw-r--r--drivers/base/regmap/regmap-i2c.c104
1 files changed, 102 insertions, 2 deletions
diff --git a/drivers/base/regmap/regmap-i2c.c b/drivers/base/regmap/regmap-i2c.c
index ebd189529760..ca193d1ef47c 100644
--- a/drivers/base/regmap/regmap-i2c.c
+++ b/drivers/base/regmap/regmap-i2c.c
@@ -14,6 +14,79 @@
#include <linux/i2c.h>
#include <linux/module.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 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 struct regmap_bus regmap_smbus_word = {
+ .reg_write = regmap_smbus_word_reg_write,
+ .reg_read = regmap_smbus_word_reg_read,
+};
+
static int regmap_i2c_write(void *context, const void *data, size_t count)
{
struct device *dev = context;
@@ -97,6 +170,23 @@ static struct regmap_bus regmap_i2c = {
.read = regmap_i2c_read,
};
+static const struct regmap_bus *regmap_get_i2c_bus(struct i2c_client *i2c,
+ const struct regmap_config *config)
+{
+ if (i2c_check_functionality(i2c->adapter, I2C_FUNC_I2C))
+ return &regmap_i2c;
+ else if (config->val_bits == 16 && config->reg_bits == 8 &&
+ i2c_check_functionality(i2c->adapter,
+ I2C_FUNC_SMBUS_WORD_DATA))
+ return &regmap_smbus_word;
+ else if (config->val_bits == 8 && config->reg_bits == 8 &&
+ i2c_check_functionality(i2c->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA))
+ return &regmap_smbus_byte;
+
+ return ERR_PTR(-ENOTSUPP);
+}
+
/**
* regmap_init_i2c(): Initialise register map
*
@@ -109,7 +199,12 @@ static struct regmap_bus regmap_i2c = {
struct regmap *regmap_init_i2c(struct i2c_client *i2c,
const struct regmap_config *config)
{
- return regmap_init(&i2c->dev, &regmap_i2c, &i2c->dev, config);
+ 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);
}
EXPORT_SYMBOL_GPL(regmap_init_i2c);
@@ -126,7 +221,12 @@ EXPORT_SYMBOL_GPL(regmap_init_i2c);
struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
const struct regmap_config *config)
{
- return devm_regmap_init(&i2c->dev, &regmap_i2c, &i2c->dev, config);
+ 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);
}
EXPORT_SYMBOL_GPL(devm_regmap_init_i2c);