On Tue, 1 Feb 2022 18:23:51 +0200 Cristian Pop <cristian.pop@xxxxxxxxxx> wrote: > 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> Hi Cristian, A few comments inline. Thanks, Jonathan > --- > changes in v2: > - Remove 'COMMON_CLK' since is not dependent on it > - Reduce some line to maximum 80 characters > - Use bulk writes instead of 'regmap_write()' with 'FIELD_GET' > - Use generic fw properties > - Pull ternary operating out on it's own line > - Remove initialisation with 0 of local 'val' variable > - Return 'regmap_write()' directly > - Use 'dev_err_probe()' instead of 'dev_err()' > - Remove 'indio_dev->dev.parent' initialisation, automatically set > drivers/iio/frequency/Kconfig | 10 + > drivers/iio/frequency/Makefile | 1 + > drivers/iio/frequency/admv4420.c | 397 +++++++++++++++++++++++++++++++ > 3 files changed, 408 insertions(+) > create mode 100644 drivers/iio/frequency/admv4420.c > > diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig > index b44036f843af..4e929e8bf255 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 > + 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..ae649d104172 > --- /dev/null > +++ b/drivers/iio/frequency/admv4420.c > @@ -0,0 +1,397 @@ > +// 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) I'm curious... What does the _ postfix indicate here? The datasheet uses it as well but I couldn't immediately spot and explanation. > +#define ADMV4420_SPI_CONFIG_1_ENDIAN_ BIT(5) > +#define ADMV4420_SPI_CONFIG_1_SDOACTIVE_ BIT(4) > +#define ADMV4420_SPI_CONFIG_1_SDOACTIVE BIT(3) > +#define ADMV4420_SPI_CONFIG_1_ENDIAN BIT(2) > +#define ADMV4420_SPI_CONFIG_1_SOFTRESET BIT(1) > + > +#define ADMV4420_REFERENCE_IN_MODE(x) (x << 1) Define a mask here and then use FIELD_PREP with that to do the shift. Same for teh one below. > +#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 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) > +{ > + u8 vals[3]; There is a fun long running discussion on whether regmap_bulk_read() is always fine with being passed buffers that aren't DMA safe. Last time I checked, the currently implementation probably is but we can't rely on it staying so. So this buffer should be DMA safe which basically means allocate it on the stack (or use the ____cache_line_aligned marking and put it at the end of the admv4420_state structure. > + int ret; > + > + vals[0] = frac_val; > + vals[1] = frac_val >> 8; > + vals[2] = frac_val >> 16; > + > + ret = regmap_bulk_write(st->regmap, ADMV4420_FRAC_L, vals, 3); > + if (ret) > + return ret; > + > + vals[0] = mod_val; > + vals[1] = mod_val >> 8; > + vals[2] = mod_val >> 16; > + > + ret = regmap_bulk_write(st->regmap, ADMV4420_MOD_L, vals, 3); > + if (ret) > + return ret; > + > + vals[0] = int_val; > + vals[1] = int_val >> 8; These look like unaligned puts. Please use appropriate put_unaligned_xx > + > + return regmap_bulk_write(st->regmap, ADMV4420_INT_L, vals, 2); > +} > + > +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); MICRO from units.h would work well here. > + div_u64_rem(st->lo_freq_hz, 1000000, val2); Also, why can't you just do *val = div_u64_rem(st->lo_freq_hz, MICRO, val2); ? If you take a look at how div_u64 is implemented it uses div_u64_rem() anyway. > + > + 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_fw_parse(struct admv4420_state *st) > +{ > + struct fwnode_handle *fwnode = dev_fwnode(&st->spi->dev); > + > + fwnode_property_read_u64(fwnode, "adi,lo-freq-hz", &st->lo_freq_hz); > + st->ref_block.ref_single_ended = fwnode_property_read_bool(fwnode, > + "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; > + u8 doubler, divide_by_2; > + > + doubler = st->ref_block.doubler_en ? 2 : 1; > + divide_by_2 = st->ref_block.divide_by_2_en ? 2 : 1; > + > + tmp = ADMV4420_REF_FREQ_HZ * doubler; Unless I'm missing something this doesn't benefit from 64 bit maths. I think all possible values fit in a 32 bit integer. If it needs 64 bit maths, perhaps a comment to say why would be good to have. > + return div_u64(tmp, st->ref_block.divider * divide_by_2); > +} > + > +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 = 10; > + > + return 0; > +} > + > +static int admv4420_setup(struct iio_dev *indio_dev) > +{ > + struct admv4420_state *st = iio_priv(indio_dev); > + u32 val; > + 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 | > + ADMV4420_SPI_CONFIG_1_ENDIAN_ | ADMV4420_SPI_CONFIG_1_ENDIAN); This could just as clearly be written as: ret = regmap_write(st->regmap, ADMV4420_SPI_CONFIG_1, ADMV4420_SPI_CONFIG_1_SDOACTIVE_ | ADMV4420_SPI_CONFIG_1_SDOACTIVE | ADMV4420_SPI_CONFIG_1_ENDIAN_ | ADMV4420_SPI_CONFIG_1_ENDIAN); and fit under 80 chars > + 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); You have multiple uses of indio_dev->dev.parent in here. I suggest using a local variable. > + 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_fw_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; > + > + return regmap_write(st->regmap, ADMV4420_ENABLES, ENABLE_PLL | ENABLE_LO | ENABLE_VCO | > + ENABLE_IFAMP | ENABLE_MIXER | ENABLE_LNA); Tidy this up. I'd rather see it aligned as return regmap_write(st->regmap, ADMV4420_ENABLES, ENABLE_PLL | ENABLE_LO | ENABLE_VCO | ENABLE_IFAMP | ENABLE_MIXER | ENABLE_LNA); so that the set of |'d values look less like different parameters. > +} > + > +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)) > + return dev_err_probe(&spi->dev, PTR_ERR(regmap), > + "Failed to initializing spi regmap\n"); > + > + st = iio_priv(indio_dev); > + st->spi = spi; > + st->regmap = regmap; > + > + 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" }, > + { }, No comma after null terminators like this. We won't ever add a line after them. > +}; > + > +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, Trivial thing but don't do table indenting link this. As you can see clearly here it doesn't result in nice alignment and it often ends up being a pain when some new entry requires re-indenting all the others. > +}; > +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");
