linux/drivers/iio/dac/ad5380.c
Colin Ian King b1e18768ef iio: dac: ad5380: fix incorrect assignment to val
Currently the pointer val is being incorrectly incremented
instead of the value pointed to by val. Fix this by adding
in the missing * indirection operator.

Addresses-Coverity: ("Unused value")
Fixes: c03f2c5368 ("staging:iio:dac: Add AD5380 driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-09-03 18:55:50 +01:00

651 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Analog devices AD5380, AD5381, AD5382, AD5383, AD5390, AD5391, AD5392
* multi-channel Digital to Analog Converters driver
*
* Copyright 2011 Analog Devices Inc.
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define AD5380_REG_DATA(x) (((x) << 2) | 3)
#define AD5380_REG_OFFSET(x) (((x) << 2) | 2)
#define AD5380_REG_GAIN(x) (((x) << 2) | 1)
#define AD5380_REG_SF_PWR_DOWN (8 << 2)
#define AD5380_REG_SF_PWR_UP (9 << 2)
#define AD5380_REG_SF_CTRL (12 << 2)
#define AD5380_CTRL_PWR_DOWN_MODE_OFFSET 13
#define AD5380_CTRL_INT_VREF_2V5 BIT(12)
#define AD5380_CTRL_INT_VREF_EN BIT(10)
/**
* struct ad5380_chip_info - chip specific information
* @channel_template: channel specification template
* @num_channels: number of channels
* @int_vref: internal vref in uV
*/
struct ad5380_chip_info {
struct iio_chan_spec channel_template;
unsigned int num_channels;
unsigned int int_vref;
};
/**
* struct ad5380_state - driver instance specific data
* @regmap: regmap instance used by the device
* @chip_info: chip model specific constants, available modes etc
* @vref_reg: vref supply regulator
* @vref: actual reference voltage used in uA
* @pwr_down: whether the chip is currently in power down mode
*/
struct ad5380_state {
struct regmap *regmap;
const struct ad5380_chip_info *chip_info;
struct regulator *vref_reg;
int vref;
bool pwr_down;
};
enum ad5380_type {
ID_AD5380_3,
ID_AD5380_5,
ID_AD5381_3,
ID_AD5381_5,
ID_AD5382_3,
ID_AD5382_5,
ID_AD5383_3,
ID_AD5383_5,
ID_AD5390_3,
ID_AD5390_5,
ID_AD5391_3,
ID_AD5391_5,
ID_AD5392_3,
ID_AD5392_5,
};
static ssize_t ad5380_read_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
struct ad5380_state *st = iio_priv(indio_dev);
return sprintf(buf, "%d\n", st->pwr_down);
}
static ssize_t ad5380_write_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
size_t len)
{
struct ad5380_state *st = iio_priv(indio_dev);
bool pwr_down;
int ret;
ret = strtobool(buf, &pwr_down);
if (ret)
return ret;
mutex_lock(&indio_dev->mlock);
if (pwr_down)
ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
else
ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
st->pwr_down = pwr_down;
mutex_unlock(&indio_dev->mlock);
return ret ? ret : len;
}
static const char * const ad5380_powerdown_modes[] = {
"100kohm_to_gnd",
"three_state",
};
static int ad5380_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct ad5380_state *st = iio_priv(indio_dev);
unsigned int mode;
int ret;
ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
if (ret)
return ret;
mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
return mode;
}
static int ad5380_set_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, unsigned int mode)
{
struct ad5380_state *st = iio_priv(indio_dev);
int ret;
ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
mode << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
return ret;
}
static const struct iio_enum ad5380_powerdown_mode_enum = {
.items = ad5380_powerdown_modes,
.num_items = ARRAY_SIZE(ad5380_powerdown_modes),
.get = ad5380_get_powerdown_mode,
.set = ad5380_set_powerdown_mode,
};
static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
long info)
{
switch (info) {
case IIO_CHAN_INFO_RAW:
return AD5380_REG_DATA(chan->address);
case IIO_CHAN_INFO_CALIBBIAS:
return AD5380_REG_OFFSET(chan->address);
case IIO_CHAN_INFO_CALIBSCALE:
return AD5380_REG_GAIN(chan->address);
default:
break;
}
return 0;
}
static int ad5380_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val, int val2, long info)
{
const unsigned int max_val = (1 << chan->scan_type.realbits);
struct ad5380_state *st = iio_priv(indio_dev);
switch (info) {
case IIO_CHAN_INFO_RAW:
case IIO_CHAN_INFO_CALIBSCALE:
if (val >= max_val || val < 0)
return -EINVAL;
return regmap_write(st->regmap,
ad5380_info_to_reg(chan, info),
val << chan->scan_type.shift);
case IIO_CHAN_INFO_CALIBBIAS:
val += (1 << chan->scan_type.realbits) / 2;
if (val >= max_val || val < 0)
return -EINVAL;
return regmap_write(st->regmap,
AD5380_REG_OFFSET(chan->address),
val << chan->scan_type.shift);
default:
break;
}
return -EINVAL;
}
static int ad5380_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val, int *val2, long info)
{
struct ad5380_state *st = iio_priv(indio_dev);
int ret;
switch (info) {
case IIO_CHAN_INFO_RAW:
case IIO_CHAN_INFO_CALIBSCALE:
ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
val);
if (ret)
return ret;
*val >>= chan->scan_type.shift;
return IIO_VAL_INT;
case IIO_CHAN_INFO_CALIBBIAS:
ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
val);
if (ret)
return ret;
*val >>= chan->scan_type.shift;
*val -= (1 << chan->scan_type.realbits) / 2;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
*val = 2 * st->vref;
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
default:
break;
}
return -EINVAL;
}
static const struct iio_info ad5380_info = {
.read_raw = ad5380_read_raw,
.write_raw = ad5380_write_raw,
};
static struct iio_chan_spec_ext_info ad5380_ext_info[] = {
{
.name = "powerdown",
.read = ad5380_read_dac_powerdown,
.write = ad5380_write_dac_powerdown,
.shared = IIO_SEPARATE,
},
IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
&ad5380_powerdown_mode_enum),
IIO_ENUM_AVAILABLE("powerdown_mode", &ad5380_powerdown_mode_enum),
{ },
};
#define AD5380_CHANNEL(_bits) { \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.output = 1, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_CALIBSCALE) | \
BIT(IIO_CHAN_INFO_CALIBBIAS), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.scan_type = { \
.sign = 'u', \
.realbits = (_bits), \
.storagebits = 16, \
.shift = 14 - (_bits), \
}, \
.ext_info = ad5380_ext_info, \
}
static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
[ID_AD5380_3] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 40,
.int_vref = 1250,
},
[ID_AD5380_5] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 40,
.int_vref = 2500,
},
[ID_AD5381_3] = {
.channel_template = AD5380_CHANNEL(12),
.num_channels = 16,
.int_vref = 1250,
},
[ID_AD5381_5] = {
.channel_template = AD5380_CHANNEL(12),
.num_channels = 16,
.int_vref = 2500,
},
[ID_AD5382_3] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 32,
.int_vref = 1250,
},
[ID_AD5382_5] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 32,
.int_vref = 2500,
},
[ID_AD5383_3] = {
.channel_template = AD5380_CHANNEL(12),
.num_channels = 32,
.int_vref = 1250,
},
[ID_AD5383_5] = {
.channel_template = AD5380_CHANNEL(12),
.num_channels = 32,
.int_vref = 2500,
},
[ID_AD5390_3] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 16,
.int_vref = 1250,
},
[ID_AD5390_5] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 16,
.int_vref = 2500,
},
[ID_AD5391_3] = {
.channel_template = AD5380_CHANNEL(12),
.num_channels = 16,
.int_vref = 1250,
},
[ID_AD5391_5] = {
.channel_template = AD5380_CHANNEL(12),
.num_channels = 16,
.int_vref = 2500,
},
[ID_AD5392_3] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 8,
.int_vref = 1250,
},
[ID_AD5392_5] = {
.channel_template = AD5380_CHANNEL(14),
.num_channels = 8,
.int_vref = 2500,
},
};
static int ad5380_alloc_channels(struct iio_dev *indio_dev)
{
struct ad5380_state *st = iio_priv(indio_dev);
struct iio_chan_spec *channels;
unsigned int i;
channels = kcalloc(st->chip_info->num_channels,
sizeof(struct iio_chan_spec), GFP_KERNEL);
if (!channels)
return -ENOMEM;
for (i = 0; i < st->chip_info->num_channels; ++i) {
channels[i] = st->chip_info->channel_template;
channels[i].channel = i;
channels[i].address = i;
}
indio_dev->channels = channels;
return 0;
}
static int ad5380_probe(struct device *dev, struct regmap *regmap,
enum ad5380_type type, const char *name)
{
struct iio_dev *indio_dev;
struct ad5380_state *st;
unsigned int ctrl = 0;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (indio_dev == NULL) {
dev_err(dev, "Failed to allocate iio device\n");
return -ENOMEM;
}
st = iio_priv(indio_dev);
dev_set_drvdata(dev, indio_dev);
st->chip_info = &ad5380_chip_info_tbl[type];
st->regmap = regmap;
indio_dev->dev.parent = dev;
indio_dev->name = name;
indio_dev->info = &ad5380_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->num_channels = st->chip_info->num_channels;
ret = ad5380_alloc_channels(indio_dev);
if (ret) {
dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
return ret;
}
if (st->chip_info->int_vref == 2500)
ctrl |= AD5380_CTRL_INT_VREF_2V5;
st->vref_reg = devm_regulator_get(dev, "vref");
if (!IS_ERR(st->vref_reg)) {
ret = regulator_enable(st->vref_reg);
if (ret) {
dev_err(dev, "Failed to enable vref regulators: %d\n",
ret);
goto error_free_reg;
}
ret = regulator_get_voltage(st->vref_reg);
if (ret < 0)
goto error_disable_reg;
st->vref = ret / 1000;
} else {
st->vref = st->chip_info->int_vref;
ctrl |= AD5380_CTRL_INT_VREF_EN;
}
ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
if (ret) {
dev_err(dev, "Failed to write to device: %d\n", ret);
goto error_disable_reg;
}
ret = iio_device_register(indio_dev);
if (ret) {
dev_err(dev, "Failed to register iio device: %d\n", ret);
goto error_disable_reg;
}
return 0;
error_disable_reg:
if (!IS_ERR(st->vref_reg))
regulator_disable(st->vref_reg);
error_free_reg:
kfree(indio_dev->channels);
return ret;
}
static int ad5380_remove(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct ad5380_state *st = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
kfree(indio_dev->channels);
if (!IS_ERR(st->vref_reg)) {
regulator_disable(st->vref_reg);
}
return 0;
}
static bool ad5380_reg_false(struct device *dev, unsigned int reg)
{
return false;
}
static const struct regmap_config ad5380_regmap_config = {
.reg_bits = 10,
.val_bits = 14,
.max_register = AD5380_REG_DATA(40),
.cache_type = REGCACHE_RBTREE,
.volatile_reg = ad5380_reg_false,
.readable_reg = ad5380_reg_false,
};
#if IS_ENABLED(CONFIG_SPI_MASTER)
static int ad5380_spi_probe(struct spi_device *spi)
{
const struct spi_device_id *id = spi_get_device_id(spi);
struct regmap *regmap;
regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
if (IS_ERR(regmap))
return PTR_ERR(regmap);
return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
}
static int ad5380_spi_remove(struct spi_device *spi)
{
return ad5380_remove(&spi->dev);
}
static const struct spi_device_id ad5380_spi_ids[] = {
{ "ad5380-3", ID_AD5380_3 },
{ "ad5380-5", ID_AD5380_5 },
{ "ad5381-3", ID_AD5381_3 },
{ "ad5381-5", ID_AD5381_5 },
{ "ad5382-3", ID_AD5382_3 },
{ "ad5382-5", ID_AD5382_5 },
{ "ad5383-3", ID_AD5383_3 },
{ "ad5383-5", ID_AD5383_5 },
{ "ad5384-3", ID_AD5380_3 },
{ "ad5384-5", ID_AD5380_5 },
{ "ad5390-3", ID_AD5390_3 },
{ "ad5390-5", ID_AD5390_5 },
{ "ad5391-3", ID_AD5391_3 },
{ "ad5391-5", ID_AD5391_5 },
{ "ad5392-3", ID_AD5392_3 },
{ "ad5392-5", ID_AD5392_5 },
{ }
};
MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
static struct spi_driver ad5380_spi_driver = {
.driver = {
.name = "ad5380",
},
.probe = ad5380_spi_probe,
.remove = ad5380_spi_remove,
.id_table = ad5380_spi_ids,
};
static inline int ad5380_spi_register_driver(void)
{
return spi_register_driver(&ad5380_spi_driver);
}
static inline void ad5380_spi_unregister_driver(void)
{
spi_unregister_driver(&ad5380_spi_driver);
}
#else
static inline int ad5380_spi_register_driver(void)
{
return 0;
}
static inline void ad5380_spi_unregister_driver(void)
{
}
#endif
#if IS_ENABLED(CONFIG_I2C)
static int ad5380_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct regmap *regmap;
regmap = devm_regmap_init_i2c(i2c, &ad5380_regmap_config);
if (IS_ERR(regmap))
return PTR_ERR(regmap);
return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
}
static int ad5380_i2c_remove(struct i2c_client *i2c)
{
return ad5380_remove(&i2c->dev);
}
static const struct i2c_device_id ad5380_i2c_ids[] = {
{ "ad5380-3", ID_AD5380_3 },
{ "ad5380-5", ID_AD5380_5 },
{ "ad5381-3", ID_AD5381_3 },
{ "ad5381-5", ID_AD5381_5 },
{ "ad5382-3", ID_AD5382_3 },
{ "ad5382-5", ID_AD5382_5 },
{ "ad5383-3", ID_AD5383_3 },
{ "ad5383-5", ID_AD5383_5 },
{ "ad5384-3", ID_AD5380_3 },
{ "ad5384-5", ID_AD5380_5 },
{ "ad5390-3", ID_AD5390_3 },
{ "ad5390-5", ID_AD5390_5 },
{ "ad5391-3", ID_AD5391_3 },
{ "ad5391-5", ID_AD5391_5 },
{ "ad5392-3", ID_AD5392_3 },
{ "ad5392-5", ID_AD5392_5 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
static struct i2c_driver ad5380_i2c_driver = {
.driver = {
.name = "ad5380",
},
.probe = ad5380_i2c_probe,
.remove = ad5380_i2c_remove,
.id_table = ad5380_i2c_ids,
};
static inline int ad5380_i2c_register_driver(void)
{
return i2c_add_driver(&ad5380_i2c_driver);
}
static inline void ad5380_i2c_unregister_driver(void)
{
i2c_del_driver(&ad5380_i2c_driver);
}
#else
static inline int ad5380_i2c_register_driver(void)
{
return 0;
}
static inline void ad5380_i2c_unregister_driver(void)
{
}
#endif
static int __init ad5380_spi_init(void)
{
int ret;
ret = ad5380_spi_register_driver();
if (ret)
return ret;
ret = ad5380_i2c_register_driver();
if (ret) {
ad5380_spi_unregister_driver();
return ret;
}
return 0;
}
module_init(ad5380_spi_init);
static void __exit ad5380_spi_exit(void)
{
ad5380_i2c_unregister_driver();
ad5380_spi_unregister_driver();
}
module_exit(ad5380_spi_exit);
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
MODULE_LICENSE("GPL v2");