mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
111 lines
2.7 KiB
111 lines
2.7 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* ltc2497.c - Driver for Analog Devices/Linear Technology LTC2497 ADC |
|
* |
|
* Copyright (C) 2017 Analog Devices Inc. |
|
* |
|
* Datasheet: http://cds.linear.com/docs/en/datasheet/2497fd.pdf |
|
*/ |
|
|
|
#include <linux/i2c.h> |
|
#include <linux/iio/iio.h> |
|
#include <linux/iio/driver.h> |
|
#include <linux/module.h> |
|
#include <linux/mod_devicetable.h> |
|
|
|
#include "ltc2497.h" |
|
|
|
struct ltc2497_driverdata { |
|
/* this must be the first member */ |
|
struct ltc2497core_driverdata common_ddata; |
|
struct i2c_client *client; |
|
/* |
|
* DMA (thus cache coherency maintenance) requires the |
|
* transfer buffers to live in their own cache lines. |
|
*/ |
|
__be32 buf ____cacheline_aligned; |
|
}; |
|
|
|
static int ltc2497_result_and_measure(struct ltc2497core_driverdata *ddata, |
|
u8 address, int *val) |
|
{ |
|
struct ltc2497_driverdata *st = |
|
container_of(ddata, struct ltc2497_driverdata, common_ddata); |
|
int ret; |
|
|
|
if (val) { |
|
ret = i2c_master_recv(st->client, (char *)&st->buf, 3); |
|
if (ret < 0) { |
|
dev_err(&st->client->dev, "i2c_master_recv failed\n"); |
|
return ret; |
|
} |
|
|
|
*val = (be32_to_cpu(st->buf) >> 14) - (1 << 17); |
|
} |
|
|
|
ret = i2c_smbus_write_byte(st->client, |
|
LTC2497_ENABLE | address); |
|
if (ret) |
|
dev_err(&st->client->dev, "i2c transfer failed: %pe\n", |
|
ERR_PTR(ret)); |
|
return ret; |
|
} |
|
|
|
static int ltc2497_probe(struct i2c_client *client, |
|
const struct i2c_device_id *id) |
|
{ |
|
struct iio_dev *indio_dev; |
|
struct ltc2497_driverdata *st; |
|
struct device *dev = &client->dev; |
|
|
|
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | |
|
I2C_FUNC_SMBUS_WRITE_BYTE)) |
|
return -EOPNOTSUPP; |
|
|
|
indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); |
|
if (!indio_dev) |
|
return -ENOMEM; |
|
|
|
st = iio_priv(indio_dev); |
|
i2c_set_clientdata(client, indio_dev); |
|
st->client = client; |
|
st->common_ddata.result_and_measure = ltc2497_result_and_measure; |
|
|
|
return ltc2497core_probe(dev, indio_dev); |
|
} |
|
|
|
static int ltc2497_remove(struct i2c_client *client) |
|
{ |
|
struct iio_dev *indio_dev = i2c_get_clientdata(client); |
|
|
|
ltc2497core_remove(indio_dev); |
|
|
|
return 0; |
|
} |
|
|
|
static const struct i2c_device_id ltc2497_id[] = { |
|
{ "ltc2497", 0 }, |
|
{ } |
|
}; |
|
MODULE_DEVICE_TABLE(i2c, ltc2497_id); |
|
|
|
static const struct of_device_id ltc2497_of_match[] = { |
|
{ .compatible = "lltc,ltc2497", }, |
|
{}, |
|
}; |
|
MODULE_DEVICE_TABLE(of, ltc2497_of_match); |
|
|
|
static struct i2c_driver ltc2497_driver = { |
|
.driver = { |
|
.name = "ltc2497", |
|
.of_match_table = ltc2497_of_match, |
|
}, |
|
.probe = ltc2497_probe, |
|
.remove = ltc2497_remove, |
|
.id_table = ltc2497_id, |
|
}; |
|
module_i2c_driver(ltc2497_driver); |
|
|
|
MODULE_AUTHOR("Michael Hennerich <[email protected]>"); |
|
MODULE_DESCRIPTION("Linear Technology LTC2497 ADC driver"); |
|
MODULE_LICENSE("GPL v2");
|
|
|