adf4371.c
// SPDX-License-Identifier: GPL-2.0
/*
* Analog Devices ADF4371 SPI Wideband Synthesizer driver
*
* Copyright 2019 Analog Devices Inc.
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gcd.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/sysfs.h>
#include <linux/spi/spi.h>
#include <linux/iio/iio.h>
/* Registers address macro */
#define ADF4371_REG(x) (x)
/* ADF4371_REG0 */
#define ADF4371_ADDR_ASC_MSK BIT(2)
#define ADF4371_ADDR_ASC(x) FIELD_PREP(ADF4371_ADDR_ASC_MSK, x)
#define ADF4371_ADDR_ASC_R_MSK BIT(5)
#define ADF4371_ADDR_ASC_R(x) FIELD_PREP(ADF4371_ADDR_ASC_R_MSK, x)
#define ADF4371_RESET_CMD 0x81
/* ADF4371_REG17 */
#define ADF4371_FRAC2WORD_L_MSK GENMASK(7, 1)
#define ADF4371_FRAC2WORD_L(x) FIELD_PREP(ADF4371_FRAC2WORD_L_MSK, x)
#define ADF4371_FRAC1WORD_MSK BIT(0)
#define ADF4371_FRAC1WORD(x) FIELD_PREP(ADF4371_FRAC1WORD_MSK, x)
/* ADF4371_REG18 */
#define ADF4371_FRAC2WORD_H_MSK GENMASK(6, 0)
#define ADF4371_FRAC2WORD_H(x) FIELD_PREP(ADF4371_FRAC2WORD_H_MSK, x)
/* ADF4371_REG1A */
#define ADF4371_MOD2WORD_MSK GENMASK(5, 0)
#define ADF4371_MOD2WORD(x) FIELD_PREP(ADF4371_MOD2WORD_MSK, x)
/* ADF4371_REG24 */
#define ADF4371_RF_DIV_SEL_MSK GENMASK(6, 4)
#define ADF4371_RF_DIV_SEL(x) FIELD_PREP(ADF4371_RF_DIV_SEL_MSK, x)
/* ADF4371_REG25 */
#define ADF4371_MUTE_LD_MSK BIT(7)
#define ADF4371_MUTE_LD(x) FIELD_PREP(ADF4371_MUTE_LD_MSK, x)
/* ADF4371_REG32 */
#define ADF4371_TIMEOUT_MSK GENMASK(1, 0)
#define ADF4371_TIMEOUT(x) FIELD_PREP(ADF4371_TIMEOUT_MSK, x)
/* ADF4371_REG34 */
#define ADF4371_VCO_ALC_TOUT_MSK GENMASK(4, 0)
#define ADF4371_VCO_ALC_TOUT(x) FIELD_PREP(ADF4371_VCO_ALC_TOUT_MSK, x)
/* Specifications */
#define ADF4371_MIN_VCO_FREQ 4000000000ULL /* 4000 MHz */
#define ADF4371_MAX_VCO_FREQ 8000000000ULL /* 8000 MHz */
#define ADF4371_MAX_OUT_RF8_FREQ ADF4371_MAX_VCO_FREQ /* Hz */
#define ADF4371_MIN_OUT_RF8_FREQ (ADF4371_MIN_VCO_FREQ / 64) /* Hz */
#define ADF4371_MAX_OUT_RF16_FREQ (ADF4371_MAX_VCO_FREQ * 2) /* Hz */
#define ADF4371_MIN_OUT_RF16_FREQ (ADF4371_MIN_VCO_FREQ * 2) /* Hz */
#define ADF4371_MAX_OUT_RF32_FREQ (ADF4371_MAX_VCO_FREQ * 4) /* Hz */
#define ADF4371_MIN_OUT_RF32_FREQ (ADF4371_MIN_VCO_FREQ * 4) /* Hz */
#define ADF4371_MAX_FREQ_PFD 250000000UL /* Hz */
#define ADF4371_MAX_FREQ_REFIN 600000000UL /* Hz */
/* MOD1 is a 24-bit primary modulus with fixed value of 2^25 */
#define ADF4371_MODULUS1 33554432ULL
/* MOD2 is the programmable, 14-bit auxiliary fractional modulus */
#define ADF4371_MAX_MODULUS2 BIT(14)
#define ADF4371_CHECK_RANGE(freq, range) \
((freq > ADF4371_MAX_ ## range) || (freq < ADF4371_MIN_ ## range))
enum {
ADF4371_FREQ,
ADF4371_POWER_DOWN,
ADF4371_CHANNEL_NAME
};
enum {
ADF4371_CH_RF8,
ADF4371_CH_RFAUX8,
ADF4371_CH_RF16,
ADF4371_CH_RF32
};
enum adf4371_variant {
ADF4371,
ADF4372
};
struct adf4371_pwrdown {
unsigned int reg;
unsigned int bit;
};
static const char * const adf4371_ch_names[] = {
"RF8x", "RFAUX8x", "RF16x", "RF32x"
};
static const struct adf4371_pwrdown adf4371_pwrdown_ch[4] = {
[ADF4371_CH_RF8] = { ADF4371_REG(0x25), 2 },
[ADF4371_CH_RFAUX8] = { ADF4371_REG(0x72), 3 },
[ADF4371_CH_RF16] = { ADF4371_REG(0x25), 3 },
[ADF4371_CH_RF32] = { ADF4371_REG(0x25), 4 },
};
static const struct reg_sequence adf4371_reg_defaults[] = {
{ ADF4371_REG(0x0), 0x18 },
{ ADF4371_REG(0x12), 0x40 },
{ ADF4371_REG(0x1E), 0x48 },
{ ADF4371_REG(0x20), 0x14 },
{ ADF4371_REG(0x22), 0x00 },
{ ADF4371_REG(0x23), 0x00 },
{ ADF4371_REG(0x24), 0x80 },
{ ADF4371_REG(0x25), 0x07 },
{ ADF4371_REG(0x27), 0xC5 },
{ ADF4371_REG(0x28), 0x83 },
{ ADF4371_REG(0x2C), 0x44 },
{ ADF4371_REG(0x2D), 0x11 },
{ ADF4371_REG(0x2E), 0x12 },
{ ADF4371_REG(0x2F), 0x94 },
{ ADF4371_REG(0x32), 0x04 },
{ ADF4371_REG(0x35), 0xFA },
{ ADF4371_REG(0x36), 0x30 },
{ ADF4371_REG(0x39), 0x07 },
{ ADF4371_REG(0x3A), 0x55 },
{ ADF4371_REG(0x3E), 0x0C },
{ ADF4371_REG(0x3F), 0x80 },
{ ADF4371_REG(0x40), 0x50 },
{ ADF4371_REG(0x41), 0x28 },
{ ADF4371_REG(0x47), 0xC0 },
{ ADF4371_REG(0x52), 0xF4 },
{ ADF4371_REG(0x70), 0x03 },
{ ADF4371_REG(0x71), 0x60 },
{ ADF4371_REG(0x72), 0x32 },
};
static const struct regmap_config adf4371_regmap_config = {
.reg_bits = 16,
.val_bits = 8,
.read_flag_mask = BIT(7),
};
struct adf4371_chip_info {
unsigned int num_channels;
const struct iio_chan_spec *channels;
};
struct adf4371_state {
struct spi_device *spi;
struct regmap *regmap;
struct clk *clkin;
/*
* Lock for accessing device registers. Some operations require
* multiple consecutive R/W operations, during which the device
* shouldn't be interrupted. The buffers are also shared across
* all operations so need to be protected on stand alone reads and
* writes.
*/
struct mutex lock;
const struct adf4371_chip_info *chip_info;
unsigned long clkin_freq;
unsigned long fpfd;
unsigned int integer;
unsigned int fract1;
unsigned int fract2;
unsigned int mod2;
unsigned int rf_div_sel;
unsigned int ref_div_factor;
u8 buf[10] ____cacheline_aligned;
};
static unsigned long long adf4371_pll_fract_n_get_rate(struct adf4371_state *st,
u32 channel)
{
unsigned long long val, tmp;
unsigned int ref_div_sel;
val = (((u64)st->integer * ADF4371_MODULUS1) + st->fract1) * st->fpfd;
tmp = (u64)st->fract2 * st->fpfd;
do_div(tmp, st->mod2);
val += tmp + ADF4371_MODULUS1 / 2;
if (channel == ADF4371_CH_RF8 || channel == ADF4371_CH_RFAUX8)
ref_div_sel = st->rf_div_sel;
else
ref_div_sel = 0;
do_div(val, ADF4371_MODULUS1 * (1 << ref_div_sel));
if (channel == ADF4371_CH_RF16)
val <<= 1;
else if (channel == ADF4371_CH_RF32)
val <<= 2;
return val;
}
static void adf4371_pll_fract_n_compute(unsigned long long vco,
unsigned long long pfd,
unsigned int *integer,
unsigned int *fract1,
unsigned int *fract2,
unsigned int *mod2)
{
unsigned long long tmp;
u32 gcd_div;
tmp = do_div(vco, pfd);
tmp = tmp * ADF4371_MODULUS1;
*fract2 = do_div(tmp, pfd);
*integer = vco;
*fract1 = tmp;
*mod2 = pfd;
while (*mod2 > ADF4371_MAX_MODULUS2) {
*mod2 >>= 1;
*fract2 >>= 1;
}
gcd_div = gcd(*fract2, *mod2);
*mod2 /= gcd_div;
*fract2 /= gcd_div;
}
static int adf4371_set_freq(struct adf4371_state *st, unsigned long long freq,
unsigned int channel)
{
u32 cp_bleed;
u8 int_mode = 0;
int ret;
switch (channel) {
case ADF4371_CH_RF8:
case ADF4371_CH_RFAUX8:
if (ADF4371_CHECK_RANGE(freq, OUT_RF8_FREQ))
return -EINVAL;
st->rf_div_sel = 0;
while (freq < ADF4371_MIN_VCO_FREQ) {
freq <<= 1;
st->rf_div_sel++;
}
break;
case ADF4371_CH_RF16:
/* ADF4371 RF16 8000...16000 MHz */
if (ADF4371_CHECK_RANGE(freq, OUT_RF16_FREQ))
return -EINVAL;
freq >>= 1;
break;
case ADF4371_CH_RF32:
/* ADF4371 RF32 16000...32000 MHz */
if (ADF4371_CHECK_RANGE(freq, OUT_RF32_FREQ))
return -EINVAL;
freq >>= 2;
break;
default:
return -EINVAL;
}
adf4371_pll_fract_n_compute(freq, st->fpfd, &st->integer, &st->fract1,
&st->fract2, &st->mod2);
st->buf[0] = st->integer >> 8;
st->buf[1] = 0x40; /* REG12 default */
st->buf[2] = 0x00;
st->buf[3] = st->fract1 & 0xFF;
st->buf[4] = st->fract1 >> 8;
st->buf[5] = st->fract1 >> 16;
st->buf[6] = ADF4371_FRAC2WORD_L(st->fract2 & 0x7F) |
ADF4371_FRAC1WORD(st->fract1 >> 24);
st->buf[7] = ADF4371_FRAC2WORD_H(st->fract2 >> 7);
st->buf[8] = st->mod2 & 0xFF;
st->buf[9] = ADF4371_MOD2WORD(st->mod2 >> 8);
ret = regmap_bulk_write(st->regmap, ADF4371_REG(0x11), st->buf, 10);
if (ret < 0)
return ret;
/*
* The R counter allows the input reference frequency to be
* divided down to produce the reference clock to the PFD
*/
ret = regmap_write(st->regmap, ADF4371_REG(0x1F), st->ref_div_factor);
if (ret < 0)
return ret;
ret = regmap_update_bits(st->regmap, ADF4371_REG(0x24),
ADF4371_RF_DIV_SEL_MSK,
ADF4371_RF_DIV_SEL(st->rf_div_sel));
if (ret < 0)
return ret;
cp_bleed = DIV_ROUND_UP(400 * 1750, st->integer * 375);
cp_bleed = clamp(cp_bleed, 1U, 255U);
ret = regmap_write(st->regmap, ADF4371_REG(0x26), cp_bleed);
if (ret < 0)
return ret;
/*
* Set to 1 when in INT mode (when FRAC1 = FRAC2 = 0),
* and set to 0 when in FRAC mode.
*/
if (st->fract1 == 0 && st->fract2 == 0)
int_mode = 0x01;
ret = regmap_write(st->regmap, ADF4371_REG(0x2B), int_mode);
if (ret < 0)
return ret;
return regmap_write(st->regmap, ADF4371_REG(0x10), st->integer & 0xFF);
}
static ssize_t adf4371_read(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
char *buf)
{
struct adf4371_state *st = iio_priv(indio_dev);
unsigned long long val = 0;
unsigned int readval, reg, bit;
int ret;
switch ((u32)private) {
case ADF4371_FREQ:
val = adf4371_pll_fract_n_get_rate(st, chan->channel);
ret = regmap_read(st->regmap, ADF4371_REG(0x7C), &readval);
if (ret < 0)
break;
if (readval == 0x00) {
dev_dbg(&st->spi->dev, "PLL un-locked\n");
ret = -EBUSY;
}
break;
case ADF4371_POWER_DOWN:
reg = adf4371_pwrdown_ch[chan->channel].reg;
bit = adf4371_pwrdown_ch[chan->channel].bit;
ret = regmap_read(st->regmap, reg, &readval);
if (ret < 0)
break;
val = !(readval & BIT(bit));
break;
case ADF4371_CHANNEL_NAME:
return sprintf(buf, "%s\n", adf4371_ch_names[chan->channel]);
default:
ret = -EINVAL;
val = 0;
break;
}
return ret < 0 ? ret : sprintf(buf, "%llu\n", val);
}
static ssize_t adf4371_write(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct adf4371_state *st = iio_priv(indio_dev);
unsigned long long freq;
bool power_down;
unsigned int bit, readval, reg;
int ret;
mutex_lock(&st->lock);
switch ((u32)private) {
case ADF4371_FREQ:
ret = kstrtoull(buf, 10, &freq);
if (ret)
break;
ret = adf4371_set_freq(st, freq, chan->channel);
break;
case ADF4371_POWER_DOWN:
ret = kstrtobool(buf, &power_down);
if (ret)
break;
reg = adf4371_pwrdown_ch[chan->channel].reg;
bit = adf4371_pwrdown_ch[chan->channel].bit;
ret = regmap_read(st->regmap, reg, &readval);
if (ret < 0)
break;
readval &= ~BIT(bit);
readval |= (!power_down << bit);
ret = regmap_write(st->regmap, reg, readval);
break;
default:
ret = -EINVAL;
break;
}
mutex_unlock(&st->lock);
return ret ? ret : len;
}
#define _ADF4371_EXT_INFO(_name, _ident) { \
.name = _name, \
.read = adf4371_read, \
.write = adf4371_write, \
.private = _ident, \
.shared = IIO_SEPARATE, \
}
static const struct iio_chan_spec_ext_info adf4371_ext_info[] = {
/*
* Ideally we use IIO_CHAN_INFO_FREQUENCY, but there are
* values > 2^32 in order to support the entire frequency range
* in Hz. Using scale is a bit ugly.
*/
_ADF4371_EXT_INFO("frequency", ADF4371_FREQ),
_ADF4371_EXT_INFO("powerdown", ADF4371_POWER_DOWN),
_ADF4371_EXT_INFO("name", ADF4371_CHANNEL_NAME),
{ },
};
#define ADF4371_CHANNEL(index) { \
.type = IIO_ALTVOLTAGE, \
.output = 1, \
.channel = index, \
.ext_info = adf4371_ext_info, \
.indexed = 1, \
}
static const struct iio_chan_spec adf4371_chan[] = {
ADF4371_CHANNEL(ADF4371_CH_RF8),
ADF4371_CHANNEL(ADF4371_CH_RFAUX8),
ADF4371_CHANNEL(ADF4371_CH_RF16),
ADF4371_CHANNEL(ADF4371_CH_RF32),
};
static const struct adf4371_chip_info adf4371_chip_info[] = {
[ADF4371] = {
.channels = adf4371_chan,
.num_channels = 4,
},
[ADF4372] = {
.channels = adf4371_chan,
.num_channels = 3,
}
};
static int adf4371_reg_access(struct iio_dev *indio_dev,
unsigned int reg,
unsigned int writeval,
unsigned int *readval)
{
struct adf4371_state *st = iio_priv(indio_dev);
if (readval)
return regmap_read(st->regmap, reg, readval);
else
return regmap_write(st->regmap, reg, writeval);
}
static const struct iio_info adf4371_info = {
.debugfs_reg_access = &adf4371_reg_access,
};
static int adf4371_setup(struct adf4371_state *st)
{
unsigned int synth_timeout = 2, timeout = 1, vco_alc_timeout = 1;
unsigned int vco_band_div, tmp;
int ret;
/* Perform a software reset */
ret = regmap_write(st->regmap, ADF4371_REG(0x0), ADF4371_RESET_CMD);
if (ret < 0)
return ret;
ret = regmap_multi_reg_write(st->regmap, adf4371_reg_defaults,
ARRAY_SIZE(adf4371_reg_defaults));
if (ret < 0)
return ret;
/* Mute to Lock Detect */
if (device_property_read_bool(&st->spi->dev, "adi,mute-till-lock-en")) {
ret = regmap_update_bits(st->regmap, ADF4371_REG(0x25),
ADF4371_MUTE_LD_MSK,
ADF4371_MUTE_LD(1));
if (ret < 0)
return ret;
}
/* Set address in ascending order, so the bulk_write() will work */
ret = regmap_update_bits(st->regmap, ADF4371_REG(0x0),
ADF4371_ADDR_ASC_MSK | ADF4371_ADDR_ASC_R_MSK,
ADF4371_ADDR_ASC(1) | ADF4371_ADDR_ASC_R(1));
if (ret < 0)
return ret;
/*
* Calculate and maximize PFD frequency
* fPFD = REFIN × ((1 + D)/(R × (1 + T)))
* Where D is the REFIN doubler bit, T is the reference divide by 2,
* R is the reference division factor
* TODO: it is assumed D and T equal 0.
*/
do {
st->ref_div_factor++;
st->fpfd = st->clkin_freq / st->ref_div_factor;
} while (st->fpfd > ADF4371_MAX_FREQ_PFD);
/* Calculate Timeouts */
vco_band_div = DIV_ROUND_UP(st->fpfd, 2400000U);
tmp = DIV_ROUND_CLOSEST(st->fpfd, 1000000U);
do {
timeout++;
if (timeout > 1023) {
timeout = 2;
synth_timeout++;
}
} while (synth_timeout * 1024 + timeout <= 20 * tmp);
do {
vco_alc_timeout++;
} while (vco_alc_timeout * 1024 - timeout <= 50 * tmp);
st->buf[0] = vco_band_div;
st->buf[1] = timeout & 0xFF;
st->buf[2] = ADF4371_TIMEOUT(timeout >> 8) | 0x04;
st->buf[3] = synth_timeout;
st->buf[4] = ADF4371_VCO_ALC_TOUT(vco_alc_timeout);
return regmap_bulk_write(st->regmap, ADF4371_REG(0x30), st->buf, 5);
}
static void adf4371_clk_disable(void *data)
{
struct adf4371_state *st = data;
clk_disable_unprepare(st->clkin);
}
static int adf4371_probe(struct spi_device *spi)
{
const struct spi_device_id *id = spi_get_device_id(spi);
struct iio_dev *indio_dev;
struct adf4371_state *st;
struct regmap *regmap;
int ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
regmap = devm_regmap_init_spi(spi, &adf4371_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
PTR_ERR(regmap));
return PTR_ERR(regmap);
}
st = iio_priv(indio_dev);
spi_set_drvdata(spi, indio_dev);
st->spi = spi;
st->regmap = regmap;
mutex_init(&st->lock);
st->chip_info = &adf4371_chip_info[id->driver_data];
indio_dev->name = id->name;
indio_dev->info = &adf4371_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = st->chip_info->channels;
indio_dev->num_channels = st->chip_info->num_channels;
st->clkin = devm_clk_get(&spi->dev, "clkin");
if (IS_ERR(st->clkin))
return PTR_ERR(st->clkin);
ret = clk_prepare_enable(st->clkin);
if (ret < 0)
return ret;
ret = devm_add_action_or_reset(&spi->dev, adf4371_clk_disable, st);
if (ret)
return ret;
st->clkin_freq = clk_get_rate(st->clkin);
ret = adf4371_setup(st);
if (ret < 0) {
dev_err(&spi->dev, "ADF4371 setup failed\n");
return ret;
}
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct spi_device_id adf4371_id_table[] = {
{ "adf4371", ADF4371 },
{ "adf4372", ADF4372 },
{}
};
MODULE_DEVICE_TABLE(spi, adf4371_id_table);
static const struct of_device_id adf4371_of_match[] = {
{ .compatible = "adi,adf4371" },
{ .compatible = "adi,adf4372" },
{ },
};
MODULE_DEVICE_TABLE(of, adf4371_of_match);
static struct spi_driver adf4371_driver = {
.driver = {
.name = "adf4371",
.of_match_table = adf4371_of_match,
},
.probe = adf4371_probe,
.id_table = adf4371_id_table,
};
module_spi_driver(adf4371_driver);
MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
MODULE_DESCRIPTION("Analog Devices ADF4371 SPI PLL");
MODULE_LICENSE("GPL");