linux-stable/drivers/iio/dac/ad5380.c
Uwe Kleine-König d6220554e4 iio: dac: ad5380: Make ad5380_remove() return void
Up to now ad5380_remove() returns zero unconditionally. Make it return
void instead which makes it easier to see in the callers that there is
no error to handle.

Also the return value of i2c and spi remove callbacks is ignored anyway.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Link: https://lore.kernel.org/r/20211013203223.2694577-8-u.kleine-koenig@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-10-19 08:30:45 +01:00

654 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
* @lock: lock to protect the data buffer during regmap ops
*/
struct ad5380_state {
struct regmap *regmap;
const struct ad5380_chip_info *chip_info;
struct regulator *vref_reg;
int vref;
bool pwr_down;
struct mutex lock;
};
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 sysfs_emit(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(&st->lock);
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(&st->lock);
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 const 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->name = name;
indio_dev->info = &ad5380_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->num_channels = st->chip_info->num_channels;
mutex_init(&st->lock);
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 void 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);
}
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)
{
ad5380_remove(&spi->dev);
return 0;
}
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)
{
ad5380_remove(&i2c->dev);
return 0;
}
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");