7cf15f4275
After commitb8a1a4cd5a("i2c: Provide a temporary .probe_new() call-back type"), all drivers being converted to .probe_new() and then03c835f498("i2c: Switch .probe() to not take an id parameter") convert back to (the new) .probe() to be able to eventually drop .probe_new() from struct i2c_driver. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20230515205048.19561-1-u.kleine-koenig@pengutronix.de Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
134 lines
3.3 KiB
C
134 lines
3.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Maxim Integrated MAX5432-MAX5435 digital potentiometer driver
|
|
* Copyright (C) 2019 Martin Kaiser <martin@kaiser.cx>
|
|
*
|
|
* Datasheet:
|
|
* https://datasheets.maximintegrated.com/en/ds/MAX5432-MAX5435.pdf
|
|
*/
|
|
|
|
#include <linux/i2c.h>
|
|
#include <linux/iio/iio.h>
|
|
#include <linux/limits.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mod_devicetable.h>
|
|
#include <linux/property.h>
|
|
|
|
/* All chip variants have 32 wiper positions. */
|
|
#define MAX5432_MAX_POS 31
|
|
|
|
#define MAX5432_OHM_50K (50 * 1000)
|
|
#define MAX5432_OHM_100K (100 * 1000)
|
|
|
|
/* Update the volatile (currently active) setting. */
|
|
#define MAX5432_CMD_VREG 0x11
|
|
|
|
struct max5432_data {
|
|
struct i2c_client *client;
|
|
unsigned long ohm;
|
|
};
|
|
|
|
static const struct iio_chan_spec max5432_channels[] = {
|
|
{
|
|
.type = IIO_RESISTANCE,
|
|
.indexed = 1,
|
|
.output = 1,
|
|
.channel = 0,
|
|
.address = MAX5432_CMD_VREG,
|
|
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
|
|
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
|
|
}
|
|
};
|
|
|
|
static int max5432_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val, int *val2, long mask)
|
|
{
|
|
struct max5432_data *data = iio_priv(indio_dev);
|
|
|
|
if (mask != IIO_CHAN_INFO_SCALE)
|
|
return -EINVAL;
|
|
|
|
if (unlikely(data->ohm > INT_MAX))
|
|
return -ERANGE;
|
|
|
|
*val = data->ohm;
|
|
*val2 = MAX5432_MAX_POS;
|
|
|
|
return IIO_VAL_FRACTIONAL;
|
|
}
|
|
|
|
static int max5432_write_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int val, int val2, long mask)
|
|
{
|
|
struct max5432_data *data = iio_priv(indio_dev);
|
|
u8 data_byte;
|
|
|
|
if (mask != IIO_CHAN_INFO_RAW)
|
|
return -EINVAL;
|
|
|
|
if (val < 0 || val > MAX5432_MAX_POS)
|
|
return -EINVAL;
|
|
|
|
if (val2 != 0)
|
|
return -EINVAL;
|
|
|
|
/* Wiper position is in bits D7-D3. (D2-D0 are don't care bits.) */
|
|
data_byte = val << 3;
|
|
return i2c_smbus_write_byte_data(data->client, chan->address,
|
|
data_byte);
|
|
}
|
|
|
|
static const struct iio_info max5432_info = {
|
|
.read_raw = max5432_read_raw,
|
|
.write_raw = max5432_write_raw,
|
|
};
|
|
|
|
static int max5432_probe(struct i2c_client *client)
|
|
{
|
|
struct device *dev = &client->dev;
|
|
struct iio_dev *indio_dev;
|
|
struct max5432_data *data;
|
|
|
|
indio_dev = devm_iio_device_alloc(dev, sizeof(struct max5432_data));
|
|
if (!indio_dev)
|
|
return -ENOMEM;
|
|
|
|
i2c_set_clientdata(client, indio_dev);
|
|
|
|
data = iio_priv(indio_dev);
|
|
data->client = client;
|
|
data->ohm = (unsigned long)device_get_match_data(dev);
|
|
|
|
indio_dev->info = &max5432_info;
|
|
indio_dev->channels = max5432_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(max5432_channels);
|
|
indio_dev->name = client->name;
|
|
|
|
return devm_iio_device_register(dev, indio_dev);
|
|
}
|
|
|
|
static const struct of_device_id max5432_dt_ids[] = {
|
|
{ .compatible = "maxim,max5432", .data = (void *)MAX5432_OHM_50K },
|
|
{ .compatible = "maxim,max5433", .data = (void *)MAX5432_OHM_100K },
|
|
{ .compatible = "maxim,max5434", .data = (void *)MAX5432_OHM_50K },
|
|
{ .compatible = "maxim,max5435", .data = (void *)MAX5432_OHM_100K },
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, max5432_dt_ids);
|
|
|
|
static struct i2c_driver max5432_driver = {
|
|
.driver = {
|
|
.name = "max5432",
|
|
.of_match_table = max5432_dt_ids,
|
|
},
|
|
.probe = max5432_probe,
|
|
};
|
|
|
|
module_i2c_driver(max5432_driver);
|
|
|
|
MODULE_AUTHOR("Martin Kaiser <martin@kaiser.cx>");
|
|
MODULE_DESCRIPTION("max5432-max5435 digital potentiometers");
|
|
MODULE_LICENSE("GPL v2");
|