mirror of https://gitee.com/openkylin/linux.git
iio: ad5272: Add support for Analog Devices digital potentiometers
Add implementation for Analog Devices AD5272 and AD5274 digital potentiometer devices. Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Phil Reid
Jonathan Cameron
parent
8730e267a1
commit
79e8a32d2a
|
|
@ -5,6 +5,16 @@
|
|||
|
||||
menu "Digital potentiometers"
|
||||
|
||||
config AD5272
|
||||
tristate "Analog Devices AD5272 and similar Digital Potentiometer driver"
|
||||
depends on I2C
|
||||
help
|
||||
Say yes here to build support for the Analog Devices AD5272 and AD5274
|
||||
digital potentiometer chip.
|
||||
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called ad5272.
|
||||
|
||||
config DS1803
|
||||
tristate "Maxim Integrated DS1803 Digital Potentiometer driver"
|
||||
depends on I2C
|
||||
|
|
|
|||
|
|
@ -4,6 +4,7 @@
|
|||
#
|
||||
|
||||
# When adding new entries keep the list in alphabetical order
|
||||
obj-$(CONFIG_AD5272) += ad5272.o
|
||||
obj-$(CONFIG_DS1803) += ds1803.o
|
||||
obj-$(CONFIG_MAX5481) += max5481.o
|
||||
obj-$(CONFIG_MAX5487) += max5487.o
|
||||
|
|
|
|||
|
|
@ -0,0 +1,231 @@
|
|||
// SPDX-License-Identifier: GPL-2.0+
|
||||
/*
|
||||
* Analog Devices AD5272 digital potentiometer driver
|
||||
* Copyright (C) 2018 Phil Reid <preid@electromag.com.au>
|
||||
*
|
||||
* Datasheet: http://www.analog.com/media/en/technical-documentation/data-sheets/AD5272_5274.pdf
|
||||
*
|
||||
* DEVID #Wipers #Positions Resistor Opts (kOhm) i2c address
|
||||
* ad5272 1 1024 20, 50, 100 01011xx
|
||||
* ad5274 1 256 20, 100 01011xx
|
||||
*/
|
||||
|
||||
#include <linux/delay.h>
|
||||
#include <linux/gpio/consumer.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/iio/iio.h>
|
||||
#include <linux/module.h>
|
||||
|
||||
#define AD5272_RDAC_WR 1
|
||||
#define AD5272_RDAC_RD 2
|
||||
#define AD5272_RESET 4
|
||||
#define AD5272_CTL 7
|
||||
|
||||
#define AD5272_RDAC_WR_EN BIT(1)
|
||||
|
||||
struct ad5272_cfg {
|
||||
int max_pos;
|
||||
int kohms;
|
||||
int shift;
|
||||
};
|
||||
|
||||
enum ad5272_type {
|
||||
AD5272_020,
|
||||
AD5272_050,
|
||||
AD5272_100,
|
||||
AD5274_020,
|
||||
AD5274_100,
|
||||
};
|
||||
|
||||
static const struct ad5272_cfg ad5272_cfg[] = {
|
||||
[AD5272_020] = { .max_pos = 1024, .kohms = 20 },
|
||||
[AD5272_050] = { .max_pos = 1024, .kohms = 50 },
|
||||
[AD5272_100] = { .max_pos = 1024, .kohms = 100 },
|
||||
[AD5274_020] = { .max_pos = 256, .kohms = 20, .shift = 2 },
|
||||
[AD5274_100] = { .max_pos = 256, .kohms = 100, .shift = 2 },
|
||||
};
|
||||
|
||||
struct ad5272_data {
|
||||
struct i2c_client *client;
|
||||
struct mutex lock;
|
||||
const struct ad5272_cfg *cfg;
|
||||
u8 buf[2] ____cacheline_aligned;
|
||||
};
|
||||
|
||||
static const struct iio_chan_spec ad5272_channel = {
|
||||
.type = IIO_RESISTANCE,
|
||||
.output = 1,
|
||||
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
|
||||
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
|
||||
};
|
||||
|
||||
static int ad5272_write(struct ad5272_data *data, int reg, int val)
|
||||
{
|
||||
int ret;
|
||||
|
||||
data->buf[0] = (reg << 2) | ((val >> 8) & 0x3);
|
||||
data->buf[1] = (u8)val;
|
||||
|
||||
mutex_lock(&data->lock);
|
||||
ret = i2c_master_send(data->client, data->buf, sizeof(data->buf));
|
||||
mutex_unlock(&data->lock);
|
||||
return ret < 0 ? ret : 0;
|
||||
}
|
||||
|
||||
static int ad5272_read(struct ad5272_data *data, int reg, int *val)
|
||||
{
|
||||
int ret;
|
||||
|
||||
data->buf[0] = reg << 2;
|
||||
data->buf[1] = 0;
|
||||
|
||||
mutex_lock(&data->lock);
|
||||
ret = i2c_master_send(data->client, data->buf, sizeof(data->buf));
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
ret = i2c_master_recv(data->client, data->buf, sizeof(data->buf));
|
||||
if (ret < 0)
|
||||
goto error;
|
||||
|
||||
*val = ((data->buf[0] & 0x3) << 8) | data->buf[1];
|
||||
ret = 0;
|
||||
error:
|
||||
mutex_unlock(&data->lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ad5272_read_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan,
|
||||
int *val, int *val2, long mask)
|
||||
{
|
||||
struct ad5272_data *data = iio_priv(indio_dev);
|
||||
int ret;
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_RAW: {
|
||||
ret = ad5272_read(data, AD5272_RDAC_RD, val);
|
||||
*val = *val >> data->cfg->shift;
|
||||
return ret ? ret : IIO_VAL_INT;
|
||||
}
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
*val = 1000 * data->cfg->kohms;
|
||||
*val2 = data->cfg->max_pos;
|
||||
return IIO_VAL_FRACTIONAL;
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int ad5272_write_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan,
|
||||
int val, int val2, long mask)
|
||||
{
|
||||
struct ad5272_data *data = iio_priv(indio_dev);
|
||||
|
||||
if (mask != IIO_CHAN_INFO_RAW)
|
||||
return -EINVAL;
|
||||
|
||||
if (val >= data->cfg->max_pos || val < 0 || val2)
|
||||
return -EINVAL;
|
||||
|
||||
return ad5272_write(data, AD5272_RDAC_WR, val << data->cfg->shift);
|
||||
}
|
||||
|
||||
static const struct iio_info ad5272_info = {
|
||||
.read_raw = ad5272_read_raw,
|
||||
.write_raw = ad5272_write_raw,
|
||||
};
|
||||
|
||||
static int ad5272_reset(struct ad5272_data *data)
|
||||
{
|
||||
struct gpio_desc *reset_gpio;
|
||||
|
||||
reset_gpio = devm_gpiod_get_optional(&data->client->dev, "reset",
|
||||
GPIOD_OUT_LOW);
|
||||
if (IS_ERR(reset_gpio))
|
||||
return PTR_ERR(reset_gpio);
|
||||
|
||||
if (reset_gpio) {
|
||||
udelay(1);
|
||||
gpiod_set_value(reset_gpio, 1);
|
||||
} else {
|
||||
ad5272_write(data, AD5272_RESET, 0);
|
||||
}
|
||||
usleep_range(1000, 2000);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ad5272_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct device *dev = &client->dev;
|
||||
struct iio_dev *indio_dev;
|
||||
struct ad5272_data *data;
|
||||
int ret;
|
||||
|
||||
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
|
||||
if (!indio_dev)
|
||||
return -ENOMEM;
|
||||
|
||||
i2c_set_clientdata(client, indio_dev);
|
||||
|
||||
data = iio_priv(indio_dev);
|
||||
data->client = client;
|
||||
mutex_init(&data->lock);
|
||||
data->cfg = &ad5272_cfg[id->driver_data];
|
||||
|
||||
ret = ad5272_reset(data);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = ad5272_write(data, AD5272_CTL, AD5272_RDAC_WR_EN);
|
||||
if (ret < 0)
|
||||
return -ENODEV;
|
||||
|
||||
indio_dev->dev.parent = dev;
|
||||
indio_dev->info = &ad5272_info;
|
||||
indio_dev->channels = &ad5272_channel;
|
||||
indio_dev->num_channels = 1;
|
||||
indio_dev->name = client->name;
|
||||
|
||||
return devm_iio_device_register(dev, indio_dev);
|
||||
}
|
||||
|
||||
#if defined(CONFIG_OF)
|
||||
static const struct of_device_id ad5272_dt_ids[] = {
|
||||
{ .compatible = "adi,ad5272-020", .data = (void *)AD5272_020 },
|
||||
{ .compatible = "adi,ad5272-050", .data = (void *)AD5272_050 },
|
||||
{ .compatible = "adi,ad5272-100", .data = (void *)AD5272_100 },
|
||||
{ .compatible = "adi,ad5274-020", .data = (void *)AD5274_020 },
|
||||
{ .compatible = "adi,ad5274-100", .data = (void *)AD5274_100 },
|
||||
{}
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, ad5272_dt_ids);
|
||||
#endif /* CONFIG_OF */
|
||||
|
||||
static const struct i2c_device_id ad5272_id[] = {
|
||||
{ "ad5272-020", AD5272_020 },
|
||||
{ "ad5272-050", AD5272_050 },
|
||||
{ "ad5272-100", AD5272_100 },
|
||||
{ "ad5274-020", AD5274_020 },
|
||||
{ "ad5274-100", AD5274_100 },
|
||||
{}
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, ad5272_id);
|
||||
|
||||
static struct i2c_driver ad5272_driver = {
|
||||
.driver = {
|
||||
.name = "ad5272",
|
||||
.of_match_table = of_match_ptr(ad5272_dt_ids),
|
||||
},
|
||||
.probe = ad5272_probe,
|
||||
.id_table = ad5272_id,
|
||||
};
|
||||
|
||||
module_i2c_driver(ad5272_driver);
|
||||
|
||||
MODULE_AUTHOR("Phil Reid <preid@eletromag.com.au>");
|
||||
MODULE_DESCRIPTION("AD5272 digital potentiometer");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
Loading…
Reference in New Issue