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linux/drivers/iio/adc/ad7780.c
Jonathan Cameron 09e3bdfe49 iio: adc: standardize on formatting for id match tables 
This is a frequent minor comment in reviews, so start cleaning up
existing drivers in the hope we get fewer cases of cut and paste.

There are not kernel wide rules for these, but for IIO the style
that I prefer (and hence most common) is:

- Space after { and before }
- No comma after terminator { }

This may cause merge conflicts but they should be trivial to resolve
hence I have not broken this into per driver patches.

Link: https://patch.msgid.link/20240818180912.719399-1-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-09-05 19:27:13 +01:00

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// SPDX-License-Identifier: GPL-2.0
/*
* AD7170/AD7171 and AD7780/AD7781 SPI ADC driver
*
* Copyright 2011 Analog Devices Inc.
* Copyright 2019 Renato Lui Geh
*/
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/bits.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/adc/ad_sigma_delta.h>
#define AD7780_RDY BIT(7)
#define AD7780_FILTER BIT(6)
#define AD7780_ERR BIT(5)
#define AD7780_ID1 BIT(4)
#define AD7780_ID0 BIT(3)
#define AD7780_GAIN BIT(2)
#define AD7170_ID 0
#define AD7171_ID 1
#define AD7780_ID 1
#define AD7781_ID 0
#define AD7780_ID_MASK (AD7780_ID0 | AD7780_ID1)
#define AD7780_PATTERN_GOOD 1
#define AD7780_PATTERN_MASK GENMASK(1, 0)
#define AD7170_PATTERN_GOOD 5
#define AD7170_PATTERN_MASK GENMASK(2, 0)
#define AD7780_GAIN_MIDPOINT 64
#define AD7780_FILTER_MIDPOINT 13350
static const unsigned int ad778x_gain[2] = { 1, 128 };
static const unsigned int ad778x_odr_avail[2] = { 10000, 16700 };
struct ad7780_chip_info {
struct iio_chan_spec channel;
unsigned int pattern_mask;
unsigned int pattern;
bool is_ad778x;
};
struct ad7780_state {
const struct ad7780_chip_info *chip_info;
struct regulator *reg;
struct gpio_desc *powerdown_gpio;
struct gpio_desc *gain_gpio;
struct gpio_desc *filter_gpio;
unsigned int gain;
unsigned int odr;
unsigned int int_vref_mv;
struct ad_sigma_delta sd;
};
enum ad7780_supported_device_ids {
ID_AD7170,
ID_AD7171,
ID_AD7780,
ID_AD7781,
};
static struct ad7780_state *ad_sigma_delta_to_ad7780(struct ad_sigma_delta *sd)
{
return container_of(sd, struct ad7780_state, sd);
}
static int ad7780_set_mode(struct ad_sigma_delta *sigma_delta,
enum ad_sigma_delta_mode mode)
{
struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta);
unsigned int val;
switch (mode) {
case AD_SD_MODE_SINGLE:
case AD_SD_MODE_CONTINUOUS:
val = 1;
break;
default:
val = 0;
break;
}
gpiod_set_value(st->powerdown_gpio, val);
return 0;
}
static int ad7780_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
struct ad7780_state *st = iio_priv(indio_dev);
int voltage_uv;
switch (m) {
case IIO_CHAN_INFO_RAW:
return ad_sigma_delta_single_conversion(indio_dev, chan, val);
case IIO_CHAN_INFO_SCALE:
voltage_uv = regulator_get_voltage(st->reg);
if (voltage_uv < 0)
return voltage_uv;
voltage_uv /= 1000;
*val = voltage_uv * st->gain;
*val2 = chan->scan_type.realbits - 1;
st->int_vref_mv = voltage_uv;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_OFFSET:
*val = -(1 << (chan->scan_type.realbits - 1));
return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
*val = st->odr;
return IIO_VAL_INT;
default:
break;
}
return -EINVAL;
}
static int ad7780_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long m)
{
struct ad7780_state *st = iio_priv(indio_dev);
const struct ad7780_chip_info *chip_info = st->chip_info;
unsigned long long vref;
unsigned int full_scale, gain;
if (!chip_info->is_ad778x)
return -EINVAL;
switch (m) {
case IIO_CHAN_INFO_SCALE:
if (val != 0)
return -EINVAL;
vref = st->int_vref_mv * 1000000LL;
full_scale = 1 << (chip_info->channel.scan_type.realbits - 1);
gain = DIV_ROUND_CLOSEST_ULL(vref, full_scale);
gain = DIV_ROUND_CLOSEST(gain, val2);
st->gain = gain;
if (gain < AD7780_GAIN_MIDPOINT)
gain = 0;
else
gain = 1;
gpiod_set_value(st->gain_gpio, gain);
break;
case IIO_CHAN_INFO_SAMP_FREQ:
if (1000*val + val2/1000 < AD7780_FILTER_MIDPOINT)
val = 0;
else
val = 1;
st->odr = ad778x_odr_avail[val];
gpiod_set_value(st->filter_gpio, val);
break;
default:
break;
}
return 0;
}
static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
unsigned int raw_sample)
{
struct ad7780_state *st = ad_sigma_delta_to_ad7780(sigma_delta);
const struct ad7780_chip_info *chip_info = st->chip_info;
if ((raw_sample & AD7780_ERR) ||
((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
return -EIO;
if (chip_info->is_ad778x) {
st->gain = ad778x_gain[raw_sample & AD7780_GAIN];
st->odr = ad778x_odr_avail[raw_sample & AD7780_FILTER];
}
return 0;
}
static const struct ad_sigma_delta_info ad7780_sigma_delta_info = {
.set_mode = ad7780_set_mode,
.postprocess_sample = ad7780_postprocess_sample,
.has_registers = false,
.irq_flags = IRQF_TRIGGER_FALLING,
};
#define _AD7780_CHANNEL(_bits, _wordsize, _mask_all) \
{ \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = 0, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_OFFSET), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.info_mask_shared_by_all = _mask_all, \
.scan_index = 1, \
.scan_type = { \
.sign = 'u', \
.realbits = (_bits), \
.storagebits = 32, \
.shift = (_wordsize) - (_bits), \
.endianness = IIO_BE, \
}, \
}
#define AD7780_CHANNEL(_bits, _wordsize) \
_AD7780_CHANNEL(_bits, _wordsize, BIT(IIO_CHAN_INFO_SAMP_FREQ))
#define AD7170_CHANNEL(_bits, _wordsize) \
_AD7780_CHANNEL(_bits, _wordsize, 0)
static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
[ID_AD7170] = {
.channel = AD7170_CHANNEL(12, 24),
.pattern = AD7170_PATTERN_GOOD,
.pattern_mask = AD7170_PATTERN_MASK,
.is_ad778x = false,
},
[ID_AD7171] = {
.channel = AD7170_CHANNEL(16, 24),
.pattern = AD7170_PATTERN_GOOD,
.pattern_mask = AD7170_PATTERN_MASK,
.is_ad778x = false,
},
[ID_AD7780] = {
.channel = AD7780_CHANNEL(24, 32),
.pattern = AD7780_PATTERN_GOOD,
.pattern_mask = AD7780_PATTERN_MASK,
.is_ad778x = true,
},
[ID_AD7781] = {
.channel = AD7780_CHANNEL(20, 32),
.pattern = AD7780_PATTERN_GOOD,
.pattern_mask = AD7780_PATTERN_MASK,
.is_ad778x = true,
},
};
static const struct iio_info ad7780_info = {
.read_raw = ad7780_read_raw,
.write_raw = ad7780_write_raw,
};
static int ad7780_init_gpios(struct device *dev, struct ad7780_state *st)
{
int ret;
st->powerdown_gpio = devm_gpiod_get_optional(dev,
"powerdown",
GPIOD_OUT_LOW);
if (IS_ERR(st->powerdown_gpio)) {
ret = PTR_ERR(st->powerdown_gpio);
dev_err(dev, "Failed to request powerdown GPIO: %d\n", ret);
return ret;
}
if (!st->chip_info->is_ad778x)
return 0;
st->gain_gpio = devm_gpiod_get_optional(dev,
"adi,gain",
GPIOD_OUT_HIGH);
if (IS_ERR(st->gain_gpio)) {
ret = PTR_ERR(st->gain_gpio);
dev_err(dev, "Failed to request gain GPIO: %d\n", ret);
return ret;
}
st->filter_gpio = devm_gpiod_get_optional(dev,
"adi,filter",
GPIOD_OUT_HIGH);
if (IS_ERR(st->filter_gpio)) {
ret = PTR_ERR(st->filter_gpio);
dev_err(dev, "Failed to request filter GPIO: %d\n", ret);
return ret;
}
return 0;
}
static void ad7780_reg_disable(void *reg)
{
regulator_disable(reg);
}
static int ad7780_probe(struct spi_device *spi)
{
struct ad7780_state *st;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
st->gain = 1;
ad_sd_init(&st->sd, indio_dev, spi, &ad7780_sigma_delta_info);
st->chip_info =
&ad7780_chip_info_tbl[spi_get_device_id(spi)->driver_data];
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = &st->chip_info->channel;
indio_dev->num_channels = 1;
indio_dev->info = &ad7780_info;
ret = ad7780_init_gpios(&spi->dev, st);
if (ret)
return ret;
st->reg = devm_regulator_get(&spi->dev, "avdd");
if (IS_ERR(st->reg))
return PTR_ERR(st->reg);
ret = regulator_enable(st->reg);
if (ret) {
dev_err(&spi->dev, "Failed to enable specified AVdd supply\n");
return ret;
}
ret = devm_add_action_or_reset(&spi->dev, ad7780_reg_disable, st->reg);
if (ret)
return ret;
ret = devm_ad_sd_setup_buffer_and_trigger(&spi->dev, indio_dev);
if (ret)
return ret;
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct spi_device_id ad7780_id[] = {
{ "ad7170", ID_AD7170 },
{ "ad7171", ID_AD7171 },
{ "ad7780", ID_AD7780 },
{ "ad7781", ID_AD7781 },
{ }
};
MODULE_DEVICE_TABLE(spi, ad7780_id);
static struct spi_driver ad7780_driver = {
.driver = {
.name = "ad7780",
},
.probe = ad7780_probe,
.id_table = ad7780_id,
};
module_spi_driver(ad7780_driver);
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD7780 and similar ADCs");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS(IIO_AD_SIGMA_DELTA);
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