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-rw-r--r--drivers/iio/frequency/adf4371.c616
1 files changed, 616 insertions, 0 deletions
diff --git a/drivers/iio/frequency/adf4371.c b/drivers/iio/frequency/adf4371.c
new file mode 100644
index 000000000..b27088464
--- /dev/null
+++ b/drivers/iio/frequency/adf4371.c
@@ -0,0 +1,616 @@
+// 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] __aligned(IIO_DMA_MINALIGN);
+};
+
+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 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_enabled(&spi->dev, "clkin");
+ if (IS_ERR(st->clkin))
+ return PTR_ERR(st->clkin);
+
+ 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");