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// SPDX-License-Identifier: GPL-2.0-only
/*
* Analog Devices AD9467 SPI ADC driver
*
* Copyright 2012-2020 Analog Devices Inc.
*/
#include <linux/cleanup.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/of.h>
#include <linux/iio/backend.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/clk.h>
/*
* ADI High-Speed ADC common spi interface registers
* See Application-Note AN-877:
* https://www.analog.com/media/en/technical-documentation/application-notes/AN-877.pdf
*/
#define AN877_ADC_REG_CHIP_PORT_CONF 0x00
#define AN877_ADC_REG_CHIP_ID 0x01
#define AN877_ADC_REG_CHIP_GRADE 0x02
#define AN877_ADC_REG_CHAN_INDEX 0x05
#define AN877_ADC_REG_TRANSFER 0xFF
#define AN877_ADC_REG_MODES 0x08
#define AN877_ADC_REG_TEST_IO 0x0D
#define AN877_ADC_REG_ADC_INPUT 0x0F
#define AN877_ADC_REG_OFFSET 0x10
#define AN877_ADC_REG_OUTPUT_MODE 0x14
#define AN877_ADC_REG_OUTPUT_ADJUST 0x15
#define AN877_ADC_REG_OUTPUT_PHASE 0x16
#define AN877_ADC_REG_OUTPUT_DELAY 0x17
#define AN877_ADC_REG_VREF 0x18
#define AN877_ADC_REG_ANALOG_INPUT 0x2C
/* AN877_ADC_REG_TEST_IO */
#define AN877_ADC_TESTMODE_OFF 0x0
#define AN877_ADC_TESTMODE_MIDSCALE_SHORT 0x1
#define AN877_ADC_TESTMODE_POS_FULLSCALE 0x2
#define AN877_ADC_TESTMODE_NEG_FULLSCALE 0x3
#define AN877_ADC_TESTMODE_ALT_CHECKERBOARD 0x4
#define AN877_ADC_TESTMODE_PN23_SEQ 0x5
#define AN877_ADC_TESTMODE_PN9_SEQ 0x6
#define AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE 0x7
#define AN877_ADC_TESTMODE_USER 0x8
#define AN877_ADC_TESTMODE_BIT_TOGGLE 0x9
#define AN877_ADC_TESTMODE_SYNC 0xA
#define AN877_ADC_TESTMODE_ONE_BIT_HIGH 0xB
#define AN877_ADC_TESTMODE_MIXED_BIT_FREQUENCY 0xC
#define AN877_ADC_TESTMODE_RAMP 0xF
/* AN877_ADC_REG_TRANSFER */
#define AN877_ADC_TRANSFER_SYNC 0x1
/* AN877_ADC_REG_OUTPUT_MODE */
#define AN877_ADC_OUTPUT_MODE_OFFSET_BINARY 0x0
#define AN877_ADC_OUTPUT_MODE_TWOS_COMPLEMENT 0x1
#define AN877_ADC_OUTPUT_MODE_GRAY_CODE 0x2
/* AN877_ADC_REG_OUTPUT_PHASE */
#define AN877_ADC_OUTPUT_EVEN_ODD_MODE_EN 0x20
#define AN877_ADC_INVERT_DCO_CLK 0x80
/* AN877_ADC_REG_OUTPUT_DELAY */
#define AN877_ADC_DCO_DELAY_ENABLE 0x80
/*
* Analog Devices AD9265 16-Bit, 125/105/80 MSPS ADC
*/
#define CHIPID_AD9265 0x64
#define AD9265_DEF_OUTPUT_MODE 0x40
#define AD9265_REG_VREF_MASK 0xC0
/*
* Analog Devices AD9434 12-Bit, 370/500 MSPS ADC
*/
#define CHIPID_AD9434 0x6A
#define AD9434_DEF_OUTPUT_MODE 0x00
#define AD9434_REG_VREF_MASK 0xC0
/*
* Analog Devices AD9467 16-Bit, 200/250 MSPS ADC
*/
#define CHIPID_AD9467 0x50
#define AD9467_DEF_OUTPUT_MODE 0x08
#define AD9467_REG_VREF_MASK 0x0F
struct ad9467_chip_info {
const char *name;
unsigned int id;
const struct iio_chan_spec *channels;
unsigned int num_channels;
const unsigned int (*scale_table)[2];
int num_scales;
unsigned long max_rate;
unsigned int default_output_mode;
unsigned int vref_mask;
};
struct ad9467_state {
const struct ad9467_chip_info *info;
struct iio_backend *back;
struct spi_device *spi;
struct clk *clk;
unsigned int output_mode;
unsigned int (*scales)[2];
struct gpio_desc *pwrdown_gpio;
/* ensure consistent state obtained on multiple related accesses */
struct mutex lock;
};
static int ad9467_spi_read(struct spi_device *spi, unsigned int reg)
{
unsigned char tbuf[2], rbuf[1];
int ret;
tbuf[0] = 0x80 | (reg >> 8);
tbuf[1] = reg & 0xFF;
ret = spi_write_then_read(spi,
tbuf, ARRAY_SIZE(tbuf),
rbuf, ARRAY_SIZE(rbuf));
if (ret < 0)
return ret;
return rbuf[0];
}
static int ad9467_spi_write(struct spi_device *spi, unsigned int reg,
unsigned int val)
{
unsigned char buf[3];
buf[0] = reg >> 8;
buf[1] = reg & 0xFF;
buf[2] = val;
return spi_write(spi, buf, ARRAY_SIZE(buf));
}
static int ad9467_reg_access(struct iio_dev *indio_dev, unsigned int reg,
unsigned int writeval, unsigned int *readval)
{
struct ad9467_state *st = iio_priv(indio_dev);
struct spi_device *spi = st->spi;
int ret;
if (!readval) {
guard(mutex)(&st->lock);
ret = ad9467_spi_write(spi, reg, writeval);
if (ret)
return ret;
return ad9467_spi_write(spi, AN877_ADC_REG_TRANSFER,
AN877_ADC_TRANSFER_SYNC);
}
ret = ad9467_spi_read(spi, reg);
if (ret < 0)
return ret;
*readval = ret;
return 0;
}
static const unsigned int ad9265_scale_table[][2] = {
{1250, 0x00}, {1500, 0x40}, {1750, 0x80}, {2000, 0xC0},
};
static const unsigned int ad9434_scale_table[][2] = {
{1600, 0x1C}, {1580, 0x1D}, {1550, 0x1E}, {1520, 0x1F}, {1500, 0x00},
{1470, 0x01}, {1440, 0x02}, {1420, 0x03}, {1390, 0x04}, {1360, 0x05},
{1340, 0x06}, {1310, 0x07}, {1280, 0x08}, {1260, 0x09}, {1230, 0x0A},
{1200, 0x0B}, {1180, 0x0C},
};
static const unsigned int ad9467_scale_table[][2] = {
{2000, 0}, {2100, 6}, {2200, 7},
{2300, 8}, {2400, 9}, {2500, 10},
};
static void __ad9467_get_scale(struct ad9467_state *st, int index,
unsigned int *val, unsigned int *val2)
{
const struct ad9467_chip_info *info = st->info;
const struct iio_chan_spec *chan = &info->channels[0];
unsigned int tmp;
tmp = (info->scale_table[index][0] * 1000000ULL) >>
chan->scan_type.realbits;
*val = tmp / 1000000;
*val2 = tmp % 1000000;
}
#define AD9467_CHAN(_chan, _si, _bits, _sign) \
{ \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = _chan, \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE), \
.scan_index = _si, \
.scan_type = { \
.sign = _sign, \
.realbits = _bits, \
.storagebits = 16, \
}, \
}
static const struct iio_chan_spec ad9434_channels[] = {
AD9467_CHAN(0, 0, 12, 'S'),
};
static const struct iio_chan_spec ad9467_channels[] = {
AD9467_CHAN(0, 0, 16, 'S'),
};
static const struct ad9467_chip_info ad9467_chip_tbl = {
.name = "ad9467",
.id = CHIPID_AD9467,
.max_rate = 250000000UL,
.scale_table = ad9467_scale_table,
.num_scales = ARRAY_SIZE(ad9467_scale_table),
.channels = ad9467_channels,
.num_channels = ARRAY_SIZE(ad9467_channels),
.default_output_mode = AD9467_DEF_OUTPUT_MODE,
.vref_mask = AD9467_REG_VREF_MASK,
};
static const struct ad9467_chip_info ad9434_chip_tbl = {
.name = "ad9434",
.id = CHIPID_AD9434,
.max_rate = 500000000UL,
.scale_table = ad9434_scale_table,
.num_scales = ARRAY_SIZE(ad9434_scale_table),
.channels = ad9434_channels,
.num_channels = ARRAY_SIZE(ad9434_channels),
.default_output_mode = AD9434_DEF_OUTPUT_MODE,
.vref_mask = AD9434_REG_VREF_MASK,
};
static const struct ad9467_chip_info ad9265_chip_tbl = {
.name = "ad9265",
.id = CHIPID_AD9265,
.max_rate = 125000000UL,
.scale_table = ad9265_scale_table,
.num_scales = ARRAY_SIZE(ad9265_scale_table),
.channels = ad9467_channels,
.num_channels = ARRAY_SIZE(ad9467_channels),
.default_output_mode = AD9265_DEF_OUTPUT_MODE,
.vref_mask = AD9265_REG_VREF_MASK,
};
static int ad9467_get_scale(struct ad9467_state *st, int *val, int *val2)
{
const struct ad9467_chip_info *info = st->info;
unsigned int i, vref_val;
int ret;
ret = ad9467_spi_read(st->spi, AN877_ADC_REG_VREF);
if (ret < 0)
return ret;
vref_val = ret & info->vref_mask;
for (i = 0; i < info->num_scales; i++) {
if (vref_val == info->scale_table[i][1])
break;
}
if (i == info->num_scales)
return -ERANGE;
__ad9467_get_scale(st, i, val, val2);
return IIO_VAL_INT_PLUS_MICRO;
}
static int ad9467_set_scale(struct ad9467_state *st, int val, int val2)
{
const struct ad9467_chip_info *info = st->info;
unsigned int scale_val[2];
unsigned int i;
int ret;
if (val != 0)
return -EINVAL;
for (i = 0; i < info->num_scales; i++) {
__ad9467_get_scale(st, i, &scale_val[0], &scale_val[1]);
if (scale_val[0] != val || scale_val[1] != val2)
continue;
guard(mutex)(&st->lock);
ret = ad9467_spi_write(st->spi, AN877_ADC_REG_VREF,
info->scale_table[i][1]);
if (ret < 0)
return ret;
return ad9467_spi_write(st->spi, AN877_ADC_REG_TRANSFER,
AN877_ADC_TRANSFER_SYNC);
}
return -EINVAL;
}
static int ad9467_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long m)
{
struct ad9467_state *st = iio_priv(indio_dev);
switch (m) {
case IIO_CHAN_INFO_SCALE:
return ad9467_get_scale(st, val, val2);
case IIO_CHAN_INFO_SAMP_FREQ:
*val = clk_get_rate(st->clk);
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
static int ad9467_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct ad9467_state *st = iio_priv(indio_dev);
const struct ad9467_chip_info *info = st->info;
long r_clk;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
return ad9467_set_scale(st, val, val2);
case IIO_CHAN_INFO_SAMP_FREQ:
r_clk = clk_round_rate(st->clk, val);
if (r_clk < 0 || r_clk > info->max_rate) {
dev_warn(&st->spi->dev,
"Error setting ADC sample rate %ld", r_clk);
return -EINVAL;
}
return clk_set_rate(st->clk, r_clk);
default:
return -EINVAL;
}
}
static int ad9467_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long mask)
{
struct ad9467_state *st = iio_priv(indio_dev);
const struct ad9467_chip_info *info = st->info;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
*vals = (const int *)st->scales;
*type = IIO_VAL_INT_PLUS_MICRO;
/* Values are stored in a 2D matrix */
*length = info->num_scales * 2;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static int ad9467_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *scan_mask)
{
struct ad9467_state *st = iio_priv(indio_dev);
unsigned int c;
int ret;
for (c = 0; c < st->info->num_channels; c++) {
if (test_bit(c, scan_mask))
ret = iio_backend_chan_enable(st->back, c);
else
ret = iio_backend_chan_disable(st->back, c);
if (ret)
return ret;
}
return 0;
}
static const struct iio_info ad9467_info = {
.read_raw = ad9467_read_raw,
.write_raw = ad9467_write_raw,
.update_scan_mode = ad9467_update_scan_mode,
.debugfs_reg_access = ad9467_reg_access,
.read_avail = ad9467_read_avail,
};
static int ad9467_outputmode_set(struct spi_device *spi, unsigned int mode)
{
int ret;
ret = ad9467_spi_write(spi, AN877_ADC_REG_OUTPUT_MODE, mode);
if (ret < 0)
return ret;
return ad9467_spi_write(spi, AN877_ADC_REG_TRANSFER,
AN877_ADC_TRANSFER_SYNC);
}
static int ad9467_scale_fill(struct ad9467_state *st)
{
const struct ad9467_chip_info *info = st->info;
unsigned int i, val1, val2;
st->scales = devm_kmalloc_array(&st->spi->dev, info->num_scales,
sizeof(*st->scales), GFP_KERNEL);
if (!st->scales)
return -ENOMEM;
for (i = 0; i < info->num_scales; i++) {
__ad9467_get_scale(st, i, &val1, &val2);
st->scales[i][0] = val1;
st->scales[i][1] = val2;
}
return 0;
}
static int ad9467_setup(struct ad9467_state *st)
{
struct iio_backend_data_fmt data = {
.sign_extend = true,
.enable = true,
};
unsigned int c, mode;
int ret;
mode = st->info->default_output_mode | AN877_ADC_OUTPUT_MODE_TWOS_COMPLEMENT;
ret = ad9467_outputmode_set(st->spi, mode);
if (ret)
return ret;
for (c = 0; c < st->info->num_channels; c++) {
ret = iio_backend_data_format_set(st->back, c, &data);
if (ret)
return ret;
}
return 0;
}
static int ad9467_reset(struct device *dev)
{
struct gpio_desc *gpio;
gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR_OR_NULL(gpio))
return PTR_ERR_OR_ZERO(gpio);
fsleep(1);
gpiod_set_value_cansleep(gpio, 0);
fsleep(10 * USEC_PER_MSEC);
return 0;
}
static int ad9467_iio_backend_get(struct ad9467_state *st)
{
struct device *dev = &st->spi->dev;
struct device_node *__back;
st->back = devm_iio_backend_get(dev, NULL);
if (!IS_ERR(st->back))
return 0;
/* If not found, don't error out as we might have legacy DT property */
if (PTR_ERR(st->back) != -ENOENT)
return PTR_ERR(st->back);
/*
* if we don't get the backend using the normal API's, use the legacy
* 'adi,adc-dev' property. So we get all nodes with that property, and
* look for the one pointing at us. Then we directly lookup that fwnode
* on the backend list of registered devices. This is done so we don't
* make io-backends mandatory which would break DT ABI.
*/
for_each_node_with_property(__back, "adi,adc-dev") {
struct device_node *__me;
__me = of_parse_phandle(__back, "adi,adc-dev", 0);
if (!__me)
continue;
if (!device_match_of_node(dev, __me)) {
of_node_put(__me);
continue;
}
of_node_put(__me);
st->back = __devm_iio_backend_get_from_fwnode_lookup(dev,
of_fwnode_handle(__back));
of_node_put(__back);
return PTR_ERR_OR_ZERO(st->back);
}
return -ENODEV;
}
static int ad9467_probe(struct spi_device *spi)
{
struct iio_dev *indio_dev;
struct ad9467_state *st;
unsigned int id;
int ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
st->spi = spi;
st->info = spi_get_device_match_data(spi);
if (!st->info)
return -ENODEV;
st->clk = devm_clk_get_enabled(&spi->dev, "adc-clk");
if (IS_ERR(st->clk))
return PTR_ERR(st->clk);
st->pwrdown_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
GPIOD_OUT_LOW);
if (IS_ERR(st->pwrdown_gpio))
return PTR_ERR(st->pwrdown_gpio);
ret = ad9467_reset(&spi->dev);
if (ret)
return ret;
ret = ad9467_scale_fill(st);
if (ret)
return ret;
id = ad9467_spi_read(spi, AN877_ADC_REG_CHIP_ID);
if (id != st->info->id) {
dev_err(&spi->dev, "Mismatch CHIP_ID, got 0x%X, expected 0x%X\n",
id, st->info->id);
return -ENODEV;
}
indio_dev->name = st->info->name;
indio_dev->channels = st->info->channels;
indio_dev->num_channels = st->info->num_channels;
indio_dev->info = &ad9467_info;
ret = ad9467_iio_backend_get(st);
if (ret)
return ret;
ret = devm_iio_backend_request_buffer(&spi->dev, st->back, indio_dev);
if (ret)
return ret;
ret = devm_iio_backend_enable(&spi->dev, st->back);
if (ret)
return ret;
ret = ad9467_setup(st);
if (ret)
return ret;
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct of_device_id ad9467_of_match[] = {
{ .compatible = "adi,ad9265", .data = &ad9265_chip_tbl, },
{ .compatible = "adi,ad9434", .data = &ad9434_chip_tbl, },
{ .compatible = "adi,ad9467", .data = &ad9467_chip_tbl, },
{}
};
MODULE_DEVICE_TABLE(of, ad9467_of_match);
static const struct spi_device_id ad9467_ids[] = {
{ "ad9265", (kernel_ulong_t)&ad9265_chip_tbl },
{ "ad9434", (kernel_ulong_t)&ad9434_chip_tbl },
{ "ad9467", (kernel_ulong_t)&ad9467_chip_tbl },
{}
};
MODULE_DEVICE_TABLE(spi, ad9467_ids);
static struct spi_driver ad9467_driver = {
.driver = {
.name = "ad9467",
.of_match_table = ad9467_of_match,
},
.probe = ad9467_probe,
.id_table = ad9467_ids,
};
module_spi_driver(ad9467_driver);
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD9467 ADC driver");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS(IIO_BACKEND);