[PATCH v1 2/2] iio:frequency:admv4420.c: Add support for ADMV4420
From: Cristian Pop
Date: Mon Jan 17 2022 - 11:41:23 EST
Add support for K Band Downconverter with Integrated
Fractional-N PLL and VCO.
More info:
https://www.analog.com/en/products/admv4420.html
Signed-off-by: Cristian Pop <cristian.pop@xxxxxxxxxx>
---
drivers/iio/frequency/Kconfig | 10 +
drivers/iio/frequency/Makefile | 1 +
drivers/iio/frequency/admv4420.c | 412 +++++++++++++++++++++++++++++++
3 files changed, 423 insertions(+)
create mode 100644 drivers/iio/frequency/admv4420.c
diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig
index b44036f843af..55aa63548c00 100644
--- a/drivers/iio/frequency/Kconfig
+++ b/drivers/iio/frequency/Kconfig
@@ -60,6 +60,16 @@ config ADMV1013
To compile this driver as a module, choose M here: the
module will be called admv1013.
+config ADMV4420
+ tristate "Analog Devices ADMV4420 K Band Downconverter"
+ depends on SPI && COMMON_CLK
+ help
+ Say yes here to build support for Analog Devices K Band
+ Downconverter with integrated Fractional-N PLL and VCO.
+
+ To compile this driver as a module, choose M here: the
+ module will be called admv4420.
+
config ADRF6780
tristate "Analog Devices ADRF6780 Microwave Upconverter"
depends on SPI
diff --git a/drivers/iio/frequency/Makefile b/drivers/iio/frequency/Makefile
index ae6899856c99..782e5baa1630 100644
--- a/drivers/iio/frequency/Makefile
+++ b/drivers/iio/frequency/Makefile
@@ -8,4 +8,5 @@ obj-$(CONFIG_AD9523) += ad9523.o
obj-$(CONFIG_ADF4350) += adf4350.o
obj-$(CONFIG_ADF4371) += adf4371.o
obj-$(CONFIG_ADMV1013) += admv1013.o
+obj-$(CONFIG_ADMV4420) += admv4420.o
obj-$(CONFIG_ADRF6780) += adrf6780.o
diff --git a/drivers/iio/frequency/admv4420.c b/drivers/iio/frequency/admv4420.c
new file mode 100644
index 000000000000..f32039ab2cd3
--- /dev/null
+++ b/drivers/iio/frequency/admv4420.c
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+/*
+ * ADMV4420
+ *
+ * Copyright 2021 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+/* ADMV4420 Register Map */
+#define ADMV4420_SPI_CONFIG_1 0x00
+#define ADMV4420_SPI_CONFIG_2 0x01
+#define ADMV4420_CHIPTYPE 0x03
+#define ADMV4420_PRODUCT_ID_L 0x04
+#define ADMV4420_PRODUCT_ID_H 0x05
+#define ADMV4420_SCRATCHPAD 0x0A
+#define ADMV4420_SPI_REV 0x0B
+#define ADMV4420_ENABLES 0x103
+#define ADMV4420_SDO_LEVEL 0x108
+#define ADMV4420_INT_L 0x200
+#define ADMV4420_INT_H 0x201
+#define ADMV4420_FRAC_L 0x202
+#define ADMV4420_FRAC_M 0x203
+#define ADMV4420_FRAC_H 0x204
+#define ADMV4420_MOD_L 0x208
+#define ADMV4420_MOD_M 0x209
+#define ADMV4420_MOD_H 0x20A
+#define ADMV4420_R_DIV_L 0x20C
+#define ADMV4420_R_DIV_H 0x20D
+#define ADMV4420_REFERENCE 0x20E
+#define ADMV4420_VCO_DATA_READBACK1 0x211
+#define ADMV4420_VCO_DATA_READBACK2 0x212
+#define ADMV4420_PLL_MUX_SEL 0x213
+#define ADMV4420_LOCK_DETECT 0x214
+#define ADMV4420_BAND_SELECT 0x215
+#define ADMV4420_VCO_ALC_TIMEOUT 0x216
+#define ADMV4420_VCO_MANUAL 0x217
+#define ADMV4420_ALC 0x219
+#define ADMV4420_VCO_TIMEOUT1 0x21C
+#define ADMV4420_VCO_TIMEOUT2 0x21D
+#define ADMV4420_VCO_BAND_DIV 0x21E
+#define ADMV4420_VCO_READBACK_SEL 0x21F
+#define ADMV4420_AUTOCAL 0x226
+#define ADMV4420_CP_STATE 0x22C
+#define ADMV4420_CP_BLEED_EN 0x22D
+#define ADMV4420_CP_CURRENT 0x22E
+#define ADMV4420_CP_BLEED 0x22F
+
+
+#define ADMV4420_SPI_CONFIG_1_SOFTRESET_ BIT(7)
+#define ADMV4420_SPI_CONFIG_1_SDOACTIVE_ BIT(4)
+#define ADMV4420_SPI_CONFIG_1_SDOACTIVE BIT(3)
+#define ADMV4420_SPI_CONFIG_1_SOFTRESET BIT(1)
+
+#define ADMV4420_REFERENCE_IN_MODE(x) (x << 1)
+#define ADMV4420_REFERENCE_DOUBLER(x) (x << 2)
+#define ADMV4420_REFERENCE_DIVIDE_BY_2_MASK BIT(0)
+#define ADMV4420_REFERENCE_MODE_MASK BIT(1)
+#define ADMV4420_REFERENCE_DOUBLER_MASK BIT(2)
+#define ADMV4420_REF_DIVIDER_MAX_VAL GENMASK(9, 0)
+#define ADMV4420_N_COUNTER_INT_MAX GENMASK(15, 0)
+#define ADMV4420_N_COUNTER_FRAC_MAX GENMASK(23, 0)
+#define ADMV4420_N_COUNTER_MOD_MAX GENMASK(23, 0)
+
+#define ADMV4420_INT_L_MASK GENMASK(7, 0)
+#define ADMV4420_INT_H_MASK GENMASK(15, 8)
+#define ADMV4420_FRAC_L_MASK GENMASK(7, 0)
+#define ADMV4420_FRAC_M_MASK GENMASK(15, 8)
+#define ADMV4420_FRAC_H_MASK GENMASK(23, 16)
+#define ADMV4420_MOD_L_MASK GENMASK(7, 0)
+#define ADMV4420_MOD_M_MASK GENMASK(15, 8)
+#define ADMV4420_MOD_H_MASK GENMASK(23, 16)
+
+#define ENABLE_PLL BIT(6)
+#define ENABLE_LO BIT(5)
+#define ENABLE_VCO BIT(3)
+#define ENABLE_IFAMP BIT(2)
+#define ENABLE_MIXER BIT(1)
+#define ENABLE_LNA BIT(0)
+
+#define ADMV4420_SCRATCH_PAD_VAL_1 0xAD
+#define ADMV4420_SCRATCH_PAD_VAL_2 0xEA
+
+#define ADMV4420_REF_FREQ_HZ 50000000
+#define MAX_N_COUNTER 655360UL
+#define MAX_R_DIVIDER 1024
+#define ADMV4420_DEFAULT_LO_FREQ_HZ 16750000000ULL
+
+enum admv4420_mux_sel {
+ ADMV4420_LOW = 0,
+ ADMV4420_LOCK_DTCT = 1,
+ ADMV4420_R_COUNTER_PER_2 = 4,
+ ADMV4420_N_CONUTER_PER_2 = 5,
+ ADMV4420_HIGH = 8,
+};
+
+struct admv4420_reference_block {
+ bool doubler_en;
+ bool divide_by_2_en;
+ bool ref_single_ended;
+ u32 divider;
+};
+
+struct admv4420_n_counter {
+ u32 int_val;
+ u32 frac_val;
+ u32 mod_val;
+ u32 n_counter;
+};
+
+struct admv4420_state {
+ struct spi_device *spi;
+ struct regmap *regmap;
+ u64 pfd_freq_hz;
+ u64 vco_freq_hz;
+ u64 lo_freq_hz;
+ struct admv4420_reference_block ref_block;
+ struct admv4420_n_counter n_counter;
+ enum admv4420_mux_sel mux_sel;
+ struct mutex lock;
+};
+
+static const struct regmap_config admv4420_regmap_config = {
+ .reg_bits = 16,
+ .val_bits = 8,
+ .read_flag_mask = BIT(7),
+};
+
+static int admv4420_reg_access(struct iio_dev *indio_dev,
+ u32 reg, u32 writeval,
+ u32 *readval)
+{
+ struct admv4420_state *st = iio_priv(indio_dev);
+
+ if (readval)
+ return regmap_read(st->regmap, reg, readval);
+ else
+ return regmap_write(st->regmap, reg, writeval);
+}
+
+static int admv4420_set_n_counter(struct admv4420_state *st, u32 int_val, u32 frac_val, u32 mod_val)
+{
+ int ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_FRAC_H, FIELD_GET(ADMV4420_FRAC_H_MASK, frac_val));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_FRAC_M, FIELD_GET(ADMV4420_FRAC_M_MASK, frac_val));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_FRAC_L, FIELD_GET(ADMV4420_FRAC_L_MASK, frac_val));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_MOD_H, FIELD_GET(ADMV4420_MOD_H_MASK, mod_val));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_MOD_M, FIELD_GET(ADMV4420_MOD_M_MASK, mod_val));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_MOD_L, FIELD_GET(ADMV4420_MOD_L_MASK, mod_val));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_INT_H, FIELD_GET(ADMV4420_INT_H_MASK, int_val));
+ if (ret)
+ return ret;
+
+ return regmap_write(st->regmap, ADMV4420_INT_L, FIELD_GET(ADMV4420_INT_L_MASK, int_val));
+}
+
+static int admv4420_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long info)
+{
+ struct admv4420_state *st = iio_priv(indio_dev);
+
+ switch (info) {
+ case IIO_CHAN_INFO_FREQUENCY:
+ *val = div_u64(st->lo_freq_hz, 1000000);
+ div_u64_rem(st->lo_freq_hz, 1000000, val2);
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info admv4420_info = {
+ .read_raw = admv4420_read_raw,
+ .debugfs_reg_access = &admv4420_reg_access,
+};
+
+static const struct iio_chan_spec admv4420_channels[] = {
+ {
+ .type = IIO_ALTVOLTAGE,
+ .output = 0,
+ .indexed = 1,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_FREQUENCY),
+ },
+};
+
+static void admv4420_dt_parse(struct admv4420_state *st)
+{
+ struct spi_device *spi = st->spi;
+
+ device_property_read_u64(&spi->dev, "adi,lo_freq_hz", &st->lo_freq_hz);
+ st->ref_block.ref_single_ended = of_property_read_bool(spi->dev.of_node,
+ "adi,ref_ext_single_ended_en");
+}
+
+static inline uint64_t admv4420_calc_pfd_vco(struct admv4420_state *st)
+{
+ return div_u64(st->vco_freq_hz * 10, st->n_counter.n_counter);
+}
+
+static inline uint64_t admv4420_calc_pfd_ref(struct admv4420_state *st)
+{
+ uint64_t tmp;
+
+ tmp = ADMV4420_REF_FREQ_HZ * (st->ref_block.doubler_en ? 2 : 1);
+ return div_u64(tmp, st->ref_block.divider * (st->ref_block.divide_by_2_en ? 2 : 1));
+}
+
+static int admv4420_calc_parameters(struct admv4420_state *st)
+{
+ u64 pfd_ref, pfd_vco;
+ bool sol_found = false;
+
+ st->ref_block.doubler_en = false;
+ st->ref_block.divide_by_2_en = false;
+ st->vco_freq_hz = div_u64(st->lo_freq_hz, 2);
+
+ for (st->ref_block.divider = 1; st->ref_block.divider < MAX_R_DIVIDER;
+ st->ref_block.divider++) {
+ pfd_ref = admv4420_calc_pfd_ref(st);
+ for (st->n_counter.n_counter = 1; st->n_counter.n_counter < MAX_N_COUNTER;
+ st->n_counter.n_counter++) {
+ pfd_vco = admv4420_calc_pfd_vco(st);
+ if (pfd_ref == pfd_vco) {
+ sol_found = true;
+ break;
+ }
+ }
+
+ if (sol_found)
+ break;
+
+ st->n_counter.n_counter = 1;
+ }
+ if (!sol_found)
+ return -1;
+
+ st->n_counter.int_val = div_u64_rem(st->n_counter.n_counter, 10, &st->n_counter.frac_val);
+ st->n_counter.mod_val = 1;
+
+ return 0;
+}
+
+static int admv4420_setup(struct iio_dev *indio_dev)
+{
+ struct admv4420_state *st = iio_priv(indio_dev);
+ u32 val = 0;
+ int ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_SPI_CONFIG_1,
+ ADMV4420_SPI_CONFIG_1_SOFTRESET_ | ADMV4420_SPI_CONFIG_1_SOFTRESET);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_SPI_CONFIG_1,
+ ADMV4420_SPI_CONFIG_1_SDOACTIVE_ | ADMV4420_SPI_CONFIG_1_SDOACTIVE);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_SCRATCHPAD, ADMV4420_SCRATCH_PAD_VAL_1);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(st->regmap, ADMV4420_SCRATCHPAD, &val);
+ if (ret)
+ return ret;
+
+ if (val != ADMV4420_SCRATCH_PAD_VAL_1) {
+ dev_err(indio_dev->dev.parent, "Failed ADMV4420 to read/write scratchpad %x ", val);
+ return -EIO;
+ }
+
+ ret = regmap_write(st->regmap, ADMV4420_SCRATCHPAD, ADMV4420_SCRATCH_PAD_VAL_2);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(st->regmap, ADMV4420_SCRATCHPAD, &val);
+ if (ret)
+ return ret;
+
+ if (val != ADMV4420_SCRATCH_PAD_VAL_2) {
+ dev_err(indio_dev->dev.parent, "Failed to read/write scratchpad %x ", val);
+ return -EIO;
+ }
+
+ st->mux_sel = ADMV4420_LOCK_DTCT;
+ st->lo_freq_hz = ADMV4420_DEFAULT_LO_FREQ_HZ;
+
+ admv4420_dt_parse(st);
+
+ ret = admv4420_calc_parameters(st);
+ if (ret) {
+ dev_err(indio_dev->dev.parent, "Failed calc parameters for %lld ", st->vco_freq_hz);
+ return ret;
+ }
+
+ ret = regmap_write(st->regmap, ADMV4420_R_DIV_L,
+ FIELD_GET(0xFF, st->ref_block.divider));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_R_DIV_H,
+ FIELD_GET(0xFF00, st->ref_block.divider));
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_REFERENCE,
+ st->ref_block.divide_by_2_en |
+ ADMV4420_REFERENCE_IN_MODE(st->ref_block.ref_single_ended) |
+ ADMV4420_REFERENCE_DOUBLER(st->ref_block.doubler_en));
+ if (ret)
+ return ret;
+
+ ret = admv4420_set_n_counter(st, st->n_counter.int_val, st->n_counter.frac_val, st->n_counter.mod_val);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_PLL_MUX_SEL, st->mux_sel);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, ADMV4420_ENABLES, ENABLE_PLL | ENABLE_LO | ENABLE_VCO |
+ ENABLE_IFAMP | ENABLE_MIXER | ENABLE_LNA);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int admv4420_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct admv4420_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, &admv4420_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&spi->dev, "Error ADMV4420 initializing spi regmap: %ld\n",
+ PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ st = iio_priv(indio_dev);
+ st->spi = spi;
+ st->regmap = regmap;
+ mutex_init(&st->lock);
+
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = "admv4420";
+ indio_dev->info = &admv4420_info;
+ indio_dev->channels = admv4420_channels;
+ indio_dev->num_channels = ARRAY_SIZE(admv4420_channels);
+
+ ret = admv4420_setup(indio_dev);
+ if (ret) {
+ dev_err(&spi->dev, "Setup ADMV4420 failed (%d)\n", ret);
+ return ret;
+ }
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct of_device_id admv4420_of_match[] = {
+ { .compatible = "adi,admv4420" },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, admv4420_of_match);
+
+static struct spi_driver admv4420_driver = {
+ .driver = {
+ .name = "admv4420",
+ .of_match_table = admv4420_of_match,
+ },
+ .probe = admv4420_probe,
+};
+module_spi_driver(admv4420_driver);
+
+MODULE_AUTHOR("Cristian Pop <cristian.pop@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices ADMV44200 K Band Downconverter");
+MODULE_LICENSE("Dual BSD/GPL");
--
2.17.1