diff options
Diffstat (limited to 'drivers/iio/frequency/adf4371.c')
-rw-r--r-- | drivers/iio/frequency/adf4371.c | 631 |
1 files changed, 631 insertions, 0 deletions
diff --git a/drivers/iio/frequency/adf4371.c b/drivers/iio/frequency/adf4371.c new file mode 100644 index 000000000..ecd5e1899 --- /dev/null +++ b/drivers/iio/frequency/adf4371.c @@ -0,0 +1,631 @@ +// 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"); |