[PATCH v2 4/4] regmap-i2c: Add smbus i2c block support

From: Markus Pargmann
Date: Thu Aug 20 2015 - 06:00:34 EST


This allows to read/write up to 32 bytes of data and is to be prefered
if supported before the register read/write smbus support.

Signed-off-by: Markus Pargmann <mpa@xxxxxxxxxxxxxx>
---
drivers/base/regmap/regmap-i2c.c | 49 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)

diff --git a/drivers/base/regmap/regmap-i2c.c b/drivers/base/regmap/regmap-i2c.c
index 4b76e33110a2..ddb9b0efb724 100644
--- a/drivers/base/regmap/regmap-i2c.c
+++ b/drivers/base/regmap/regmap-i2c.c
@@ -209,11 +209,60 @@ static struct regmap_bus regmap_i2c = {
.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;
+ if (count >= I2C_SMBUS_BLOCK_MAX)
+ return -E2BIG;
+
+ --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;
+ if (val_size >= I2C_SMBUS_BLOCK_MAX)
+ return -E2BIG;
+
+ 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 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,
+ .max_raw_write = I2C_SMBUS_BLOCK_MAX,
+};
+
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->reg_bits == 8 &&
+ i2c_check_functionality(i2c->adapter,
+ I2C_FUNC_SMBUS_I2C_BLOCK))
+ return &regmap_i2c_smbus_i2c_block;
else if (config->val_bits == 16 && config->reg_bits == 8 &&
i2c_check_functionality(i2c->adapter,
I2C_FUNC_SMBUS_WORD_DATA))
--
2.4.6

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