mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-02 16:44:10 +08:00
iio:adc:ad7949: Add AD7949 ADC driver family
Compatible with AD7682 and AD7689 chips. It is a Analog Devices ADC driver 14/16 bits 4/8 channels with SPI protocol Datasheet of the device: http://www.analog.com/media/en/technical-documentation/data-sheets/AD7949.pdf Signed-off-by: Charles-Antoine Couret <charles-antoine.couret@essensium.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Charles-Antoine Couret
Jonathan Cameron
parent
3138bbc129
commit
7f40e06143
@ -116,6 +116,16 @@ config AD7923
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called ad7923.
|
||||
|
||||
config AD7949
|
||||
tristate "Analog Devices AD7949 and similar ADCs driver"
|
||||
depends on SPI
|
||||
help
|
||||
Say yes here to build support for Analog Devices
|
||||
AD7949, AD7682, AD7689 8 Channel ADCs.
|
||||
|
||||
To compile this driver as a module, choose M here: the
|
||||
module will be called ad7949.
|
||||
|
||||
config AD799X
|
||||
tristate "Analog Devices AD799x ADC driver"
|
||||
depends on I2C
|
||||
|
||||
@ -14,6 +14,7 @@ obj-$(CONFIG_AD7766) += ad7766.o
|
||||
obj-$(CONFIG_AD7791) += ad7791.o
|
||||
obj-$(CONFIG_AD7793) += ad7793.o
|
||||
obj-$(CONFIG_AD7887) += ad7887.o
|
||||
obj-$(CONFIG_AD7949) += ad7949.o
|
||||
obj-$(CONFIG_AD799X) += ad799x.o
|
||||
obj-$(CONFIG_ASPEED_ADC) += aspeed_adc.o
|
||||
obj-$(CONFIG_AT91_ADC) += at91_adc.o
|
||||
|
||||
347
drivers/iio/adc/ad7949.c
Normal file
347
drivers/iio/adc/ad7949.c
Normal file
@ -0,0 +1,347 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
/* ad7949.c - Analog Devices ADC driver 14/16 bits 4/8 channels
|
||||
*
|
||||
* Copyright (C) 2018 CMC NV
|
||||
*
|
||||
* http://www.analog.com/media/en/technical-documentation/data-sheets/AD7949.pdf
|
||||
*/
|
||||
|
||||
#include <linux/delay.h>
|
||||
#include <linux/iio/iio.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/regulator/consumer.h>
|
||||
#include <linux/spi/spi.h>
|
||||
|
||||
#define AD7949_MASK_CHANNEL_SEL GENMASK(9, 7)
|
||||
#define AD7949_MASK_TOTAL GENMASK(13, 0)
|
||||
#define AD7949_OFFSET_CHANNEL_SEL 7
|
||||
#define AD7949_CFG_READ_BACK 0x1
|
||||
#define AD7949_CFG_REG_SIZE_BITS 14
|
||||
|
||||
enum {
|
||||
ID_AD7949 = 0,
|
||||
ID_AD7682,
|
||||
ID_AD7689,
|
||||
};
|
||||
|
||||
struct ad7949_adc_spec {
|
||||
u8 num_channels;
|
||||
u8 resolution;
|
||||
};
|
||||
|
||||
static const struct ad7949_adc_spec ad7949_adc_spec[] = {
|
||||
[ID_AD7949] = { .num_channels = 8, .resolution = 14 },
|
||||
[ID_AD7682] = { .num_channels = 4, .resolution = 16 },
|
||||
[ID_AD7689] = { .num_channels = 8, .resolution = 16 },
|
||||
};
|
||||
|
||||
/**
|
||||
* struct ad7949_adc_chip - AD ADC chip
|
||||
* @lock: protects write sequences
|
||||
* @vref: regulator generating Vref
|
||||
* @iio_dev: reference to iio structure
|
||||
* @spi: reference to spi structure
|
||||
* @resolution: resolution of the chip
|
||||
* @cfg: copy of the configuration register
|
||||
* @current_channel: current channel in use
|
||||
* @buffer: buffer to send / receive data to / from device
|
||||
*/
|
||||
struct ad7949_adc_chip {
|
||||
struct mutex lock;
|
||||
struct regulator *vref;
|
||||
struct iio_dev *indio_dev;
|
||||
struct spi_device *spi;
|
||||
u8 resolution;
|
||||
u16 cfg;
|
||||
unsigned int current_channel;
|
||||
u32 buffer ____cacheline_aligned;
|
||||
};
|
||||
|
||||
static bool ad7949_spi_cfg_is_read_back(struct ad7949_adc_chip *ad7949_adc)
|
||||
{
|
||||
if (!(ad7949_adc->cfg & AD7949_CFG_READ_BACK))
|
||||
return true;
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
static int ad7949_spi_bits_per_word(struct ad7949_adc_chip *ad7949_adc)
|
||||
{
|
||||
int ret = ad7949_adc->resolution;
|
||||
|
||||
if (ad7949_spi_cfg_is_read_back(ad7949_adc))
|
||||
ret += AD7949_CFG_REG_SIZE_BITS;
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ad7949_spi_write_cfg(struct ad7949_adc_chip *ad7949_adc, u16 val,
|
||||
u16 mask)
|
||||
{
|
||||
int ret;
|
||||
int bits_per_word = ad7949_spi_bits_per_word(ad7949_adc);
|
||||
int shift = bits_per_word - AD7949_CFG_REG_SIZE_BITS;
|
||||
struct spi_message msg;
|
||||
struct spi_transfer tx[] = {
|
||||
{
|
||||
.tx_buf = &ad7949_adc->buffer,
|
||||
.len = 4,
|
||||
.bits_per_word = bits_per_word,
|
||||
},
|
||||
};
|
||||
|
||||
ad7949_adc->cfg = (val & mask) | (ad7949_adc->cfg & ~mask);
|
||||
ad7949_adc->buffer = ad7949_adc->cfg << shift;
|
||||
spi_message_init_with_transfers(&msg, tx, 1);
|
||||
ret = spi_sync(ad7949_adc->spi, &msg);
|
||||
|
||||
/*
|
||||
* This delay is to avoid a new request before the required time to
|
||||
* send a new command to the device
|
||||
*/
|
||||
udelay(2);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val,
|
||||
unsigned int channel)
|
||||
{
|
||||
int ret;
|
||||
int bits_per_word = ad7949_spi_bits_per_word(ad7949_adc);
|
||||
int mask = GENMASK(ad7949_adc->resolution, 0);
|
||||
struct spi_message msg;
|
||||
struct spi_transfer tx[] = {
|
||||
{
|
||||
.rx_buf = &ad7949_adc->buffer,
|
||||
.len = 4,
|
||||
.bits_per_word = bits_per_word,
|
||||
},
|
||||
};
|
||||
|
||||
ret = ad7949_spi_write_cfg(ad7949_adc,
|
||||
channel << AD7949_OFFSET_CHANNEL_SEL,
|
||||
AD7949_MASK_CHANNEL_SEL);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ad7949_adc->buffer = 0;
|
||||
spi_message_init_with_transfers(&msg, tx, 1);
|
||||
ret = spi_sync(ad7949_adc->spi, &msg);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/*
|
||||
* This delay is to avoid a new request before the required time to
|
||||
* send a new command to the device
|
||||
*/
|
||||
udelay(2);
|
||||
|
||||
ad7949_adc->current_channel = channel;
|
||||
|
||||
if (ad7949_spi_cfg_is_read_back(ad7949_adc))
|
||||
*val = (ad7949_adc->buffer >> AD7949_CFG_REG_SIZE_BITS) & mask;
|
||||
else
|
||||
*val = ad7949_adc->buffer & mask;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
#define AD7949_ADC_CHANNEL(chan) { \
|
||||
.type = IIO_VOLTAGE, \
|
||||
.indexed = 1, \
|
||||
.channel = (chan), \
|
||||
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
|
||||
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
|
||||
}
|
||||
|
||||
static const struct iio_chan_spec ad7949_adc_channels[] = {
|
||||
AD7949_ADC_CHANNEL(0),
|
||||
AD7949_ADC_CHANNEL(1),
|
||||
AD7949_ADC_CHANNEL(2),
|
||||
AD7949_ADC_CHANNEL(3),
|
||||
AD7949_ADC_CHANNEL(4),
|
||||
AD7949_ADC_CHANNEL(5),
|
||||
AD7949_ADC_CHANNEL(6),
|
||||
AD7949_ADC_CHANNEL(7),
|
||||
};
|
||||
|
||||
static int ad7949_spi_read_raw(struct iio_dev *indio_dev,
|
||||
struct iio_chan_spec const *chan,
|
||||
int *val, int *val2, long mask)
|
||||
{
|
||||
struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev);
|
||||
int ret;
|
||||
|
||||
if (!val)
|
||||
return -EINVAL;
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_RAW:
|
||||
mutex_lock(&ad7949_adc->lock);
|
||||
ret = ad7949_spi_read_channel(ad7949_adc, val, chan->channel);
|
||||
mutex_unlock(&ad7949_adc->lock);
|
||||
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
return IIO_VAL_INT;
|
||||
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
ret = regulator_get_voltage(ad7949_adc->vref);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
*val = ret / 5000;
|
||||
return IIO_VAL_INT;
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int ad7949_spi_reg_access(struct iio_dev *indio_dev,
|
||||
unsigned int reg, unsigned int writeval,
|
||||
unsigned int *readval)
|
||||
{
|
||||
struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev);
|
||||
int ret = 0;
|
||||
|
||||
if (readval)
|
||||
*readval = ad7949_adc->cfg;
|
||||
else
|
||||
ret = ad7949_spi_write_cfg(ad7949_adc,
|
||||
writeval & AD7949_MASK_TOTAL, AD7949_MASK_TOTAL);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static const struct iio_info ad7949_spi_info = {
|
||||
.read_raw = ad7949_spi_read_raw,
|
||||
.debugfs_reg_access = ad7949_spi_reg_access,
|
||||
};
|
||||
|
||||
static int ad7949_spi_init(struct ad7949_adc_chip *ad7949_adc)
|
||||
{
|
||||
int ret;
|
||||
int val;
|
||||
|
||||
/* Sequencer disabled, CFG readback disabled, IN0 as default channel */
|
||||
ad7949_adc->current_channel = 0;
|
||||
ret = ad7949_spi_write_cfg(ad7949_adc, 0x3C79, AD7949_MASK_TOTAL);
|
||||
|
||||
/*
|
||||
* Do two dummy conversions to apply the first configuration setting.
|
||||
* Required only after the start up of the device.
|
||||
*/
|
||||
ad7949_spi_read_channel(ad7949_adc, &val, ad7949_adc->current_channel);
|
||||
ad7949_spi_read_channel(ad7949_adc, &val, ad7949_adc->current_channel);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ad7949_spi_probe(struct spi_device *spi)
|
||||
{
|
||||
struct device *dev = &spi->dev;
|
||||
const struct ad7949_adc_spec *spec;
|
||||
struct ad7949_adc_chip *ad7949_adc;
|
||||
struct iio_dev *indio_dev;
|
||||
int ret;
|
||||
|
||||
indio_dev = devm_iio_device_alloc(dev, sizeof(*ad7949_adc));
|
||||
if (!indio_dev) {
|
||||
dev_err(dev, "can not allocate iio device\n");
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
indio_dev->dev.parent = dev;
|
||||
indio_dev->dev.of_node = dev->of_node;
|
||||
indio_dev->info = &ad7949_spi_info;
|
||||
indio_dev->name = spi_get_device_id(spi)->name;
|
||||
indio_dev->modes = INDIO_DIRECT_MODE;
|
||||
indio_dev->channels = ad7949_adc_channels;
|
||||
spi_set_drvdata(spi, indio_dev);
|
||||
|
||||
ad7949_adc = iio_priv(indio_dev);
|
||||
ad7949_adc->indio_dev = indio_dev;
|
||||
ad7949_adc->spi = spi;
|
||||
|
||||
spec = &ad7949_adc_spec[spi_get_device_id(spi)->driver_data];
|
||||
indio_dev->num_channels = spec->num_channels;
|
||||
ad7949_adc->resolution = spec->resolution;
|
||||
|
||||
ad7949_adc->vref = devm_regulator_get(dev, "vref");
|
||||
if (IS_ERR(ad7949_adc->vref)) {
|
||||
dev_err(dev, "fail to request regulator\n");
|
||||
return PTR_ERR(ad7949_adc->vref);
|
||||
}
|
||||
|
||||
ret = regulator_enable(ad7949_adc->vref);
|
||||
if (ret < 0) {
|
||||
dev_err(dev, "fail to enable regulator\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
mutex_init(&ad7949_adc->lock);
|
||||
|
||||
ret = ad7949_spi_init(ad7949_adc);
|
||||
if (ret) {
|
||||
dev_err(dev, "enable to init this device: %d\n", ret);
|
||||
goto err;
|
||||
}
|
||||
|
||||
ret = iio_device_register(indio_dev);
|
||||
if (ret) {
|
||||
dev_err(dev, "fail to register iio device: %d\n", ret);
|
||||
goto err;
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
err:
|
||||
mutex_destroy(&ad7949_adc->lock);
|
||||
regulator_disable(ad7949_adc->vref);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ad7949_spi_remove(struct spi_device *spi)
|
||||
{
|
||||
struct iio_dev *indio_dev = spi_get_drvdata(spi);
|
||||
struct ad7949_adc_chip *ad7949_adc = iio_priv(indio_dev);
|
||||
|
||||
iio_device_unregister(indio_dev);
|
||||
mutex_destroy(&ad7949_adc->lock);
|
||||
regulator_disable(ad7949_adc->vref);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct of_device_id ad7949_spi_of_id[] = {
|
||||
{ .compatible = "adi,ad7949" },
|
||||
{ .compatible = "adi,ad7682" },
|
||||
{ .compatible = "adi,ad7689" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, ad7949_spi_of_id);
|
||||
|
||||
static const struct spi_device_id ad7949_spi_id[] = {
|
||||
{ "ad7949", ID_AD7949 },
|
||||
{ "ad7682", ID_AD7682 },
|
||||
{ "ad7689", ID_AD7689 },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(spi, ad7949_spi_id);
|
||||
|
||||
static struct spi_driver ad7949_spi_driver = {
|
||||
.driver = {
|
||||
.name = "ad7949",
|
||||
.of_match_table = ad7949_spi_of_id,
|
||||
},
|
||||
.probe = ad7949_spi_probe,
|
||||
.remove = ad7949_spi_remove,
|
||||
.id_table = ad7949_spi_id,
|
||||
};
|
||||
module_spi_driver(ad7949_spi_driver);
|
||||
|
||||
MODULE_AUTHOR("Charles-Antoine Couret <charles-antoine.couret@essensium.com>");
|
||||
MODULE_DESCRIPTION("Analog Devices 14/16-bit 8-channel ADC driver");
|
||||
MODULE_LICENSE("GPL v2");
|
||||
Loading…
Reference in New Issue
Block a user