diff options
Diffstat (limited to 'drivers/iio/frequency/adf4350.c')
-rw-r--r-- | drivers/iio/frequency/adf4350.c | 588 |
1 files changed, 588 insertions, 0 deletions
diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c new file mode 100644 index 000000000..4abf80f75 --- /dev/null +++ b/drivers/iio/frequency/adf4350.c @@ -0,0 +1,588 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ADF4350/ADF4351 SPI Wideband Synthesizer driver + * + * Copyright 2012-2013 Analog Devices Inc. + */ + +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/slab.h> +#include <linux/sysfs.h> +#include <linux/spi/spi.h> +#include <linux/regulator/consumer.h> +#include <linux/err.h> +#include <linux/gcd.h> +#include <linux/gpio/consumer.h> +#include <asm/div64.h> +#include <linux/clk.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/frequency/adf4350.h> + +enum { + ADF4350_FREQ, + ADF4350_FREQ_REFIN, + ADF4350_FREQ_RESOLUTION, + ADF4350_PWRDOWN, +}; + +struct adf4350_state { + struct spi_device *spi; + struct gpio_desc *lock_detect_gpiod; + struct adf4350_platform_data *pdata; + struct clk *clk; + unsigned long clkin; + unsigned long chspc; /* Channel Spacing */ + unsigned long fpfd; /* Phase Frequency Detector */ + unsigned long min_out_freq; + unsigned r0_fract; + unsigned r0_int; + unsigned r1_mod; + unsigned r4_rf_div_sel; + unsigned long regs[6]; + unsigned long regs_hw[6]; + unsigned long long freq_req; + /* + * Lock to protect the state of the device from potential concurrent + * writes. The device is configured via a sequence of SPI writes, + * and this lock is meant to prevent the start of another sequence + * before another one has finished. + */ + struct mutex lock; + /* + * DMA (thus cache coherency maintenance) may require that + * transfer buffers live in their own cache lines. + */ + __be32 val __aligned(IIO_DMA_MINALIGN); +}; + +static struct adf4350_platform_data default_pdata = { + .channel_spacing = 10000, + .r2_user_settings = ADF4350_REG2_PD_POLARITY_POS | + ADF4350_REG2_CHARGE_PUMP_CURR_uA(2500), + .r3_user_settings = ADF4350_REG3_12BIT_CLKDIV_MODE(0), + .r4_user_settings = ADF4350_REG4_OUTPUT_PWR(3) | + ADF4350_REG4_MUTE_TILL_LOCK_EN, +}; + +static int adf4350_sync_config(struct adf4350_state *st) +{ + int ret, i, doublebuf = 0; + + for (i = ADF4350_REG5; i >= ADF4350_REG0; i--) { + if ((st->regs_hw[i] != st->regs[i]) || + ((i == ADF4350_REG0) && doublebuf)) { + switch (i) { + case ADF4350_REG1: + case ADF4350_REG4: + doublebuf = 1; + break; + } + + st->val = cpu_to_be32(st->regs[i] | i); + ret = spi_write(st->spi, &st->val, 4); + if (ret < 0) + return ret; + st->regs_hw[i] = st->regs[i]; + dev_dbg(&st->spi->dev, "[%d] 0x%X\n", + i, (u32)st->regs[i] | i); + } + } + return 0; +} + +static int adf4350_reg_access(struct iio_dev *indio_dev, + unsigned reg, unsigned writeval, + unsigned *readval) +{ + struct adf4350_state *st = iio_priv(indio_dev); + int ret; + + if (reg > ADF4350_REG5) + return -EINVAL; + + mutex_lock(&st->lock); + if (readval == NULL) { + st->regs[reg] = writeval & ~(BIT(0) | BIT(1) | BIT(2)); + ret = adf4350_sync_config(st); + } else { + *readval = st->regs_hw[reg]; + ret = 0; + } + mutex_unlock(&st->lock); + + return ret; +} + +static int adf4350_tune_r_cnt(struct adf4350_state *st, unsigned short r_cnt) +{ + struct adf4350_platform_data *pdata = st->pdata; + + do { + r_cnt++; + st->fpfd = (st->clkin * (pdata->ref_doubler_en ? 2 : 1)) / + (r_cnt * (pdata->ref_div2_en ? 2 : 1)); + } while (st->fpfd > ADF4350_MAX_FREQ_PFD); + + return r_cnt; +} + +static int adf4350_set_freq(struct adf4350_state *st, unsigned long long freq) +{ + struct adf4350_platform_data *pdata = st->pdata; + u64 tmp; + u32 div_gcd, prescaler, chspc; + u16 mdiv, r_cnt = 0; + u8 band_sel_div; + + if (freq > ADF4350_MAX_OUT_FREQ || freq < st->min_out_freq) + return -EINVAL; + + if (freq > ADF4350_MAX_FREQ_45_PRESC) { + prescaler = ADF4350_REG1_PRESCALER; + mdiv = 75; + } else { + prescaler = 0; + mdiv = 23; + } + + st->r4_rf_div_sel = 0; + + while (freq < ADF4350_MIN_VCO_FREQ) { + freq <<= 1; + st->r4_rf_div_sel++; + } + + /* + * Allow a predefined reference division factor + * if not set, compute our own + */ + if (pdata->ref_div_factor) + r_cnt = pdata->ref_div_factor - 1; + + chspc = st->chspc; + + do { + do { + do { + r_cnt = adf4350_tune_r_cnt(st, r_cnt); + st->r1_mod = st->fpfd / chspc; + if (r_cnt > ADF4350_MAX_R_CNT) { + /* try higher spacing values */ + chspc++; + r_cnt = 0; + } + } while ((st->r1_mod > ADF4350_MAX_MODULUS) && r_cnt); + } while (r_cnt == 0); + + tmp = freq * (u64)st->r1_mod + (st->fpfd >> 1); + do_div(tmp, st->fpfd); /* Div round closest (n + d/2)/d */ + st->r0_fract = do_div(tmp, st->r1_mod); + st->r0_int = tmp; + } while (mdiv > st->r0_int); + + band_sel_div = DIV_ROUND_UP(st->fpfd, ADF4350_MAX_BANDSEL_CLK); + + if (st->r0_fract && st->r1_mod) { + div_gcd = gcd(st->r1_mod, st->r0_fract); + st->r1_mod /= div_gcd; + st->r0_fract /= div_gcd; + } else { + st->r0_fract = 0; + st->r1_mod = 1; + } + + dev_dbg(&st->spi->dev, "VCO: %llu Hz, PFD %lu Hz\n" + "REF_DIV %d, R0_INT %d, R0_FRACT %d\n" + "R1_MOD %d, RF_DIV %d\nPRESCALER %s, BAND_SEL_DIV %d\n", + freq, st->fpfd, r_cnt, st->r0_int, st->r0_fract, st->r1_mod, + 1 << st->r4_rf_div_sel, prescaler ? "8/9" : "4/5", + band_sel_div); + + st->regs[ADF4350_REG0] = ADF4350_REG0_INT(st->r0_int) | + ADF4350_REG0_FRACT(st->r0_fract); + + st->regs[ADF4350_REG1] = ADF4350_REG1_PHASE(1) | + ADF4350_REG1_MOD(st->r1_mod) | + prescaler; + + st->regs[ADF4350_REG2] = + ADF4350_REG2_10BIT_R_CNT(r_cnt) | + ADF4350_REG2_DOUBLE_BUFF_EN | + (pdata->ref_doubler_en ? ADF4350_REG2_RMULT2_EN : 0) | + (pdata->ref_div2_en ? ADF4350_REG2_RDIV2_EN : 0) | + (pdata->r2_user_settings & (ADF4350_REG2_PD_POLARITY_POS | + ADF4350_REG2_LDP_6ns | ADF4350_REG2_LDF_INT_N | + ADF4350_REG2_CHARGE_PUMP_CURR_uA(5000) | + ADF4350_REG2_MUXOUT(0x7) | ADF4350_REG2_NOISE_MODE(0x3))); + + st->regs[ADF4350_REG3] = pdata->r3_user_settings & + (ADF4350_REG3_12BIT_CLKDIV(0xFFF) | + ADF4350_REG3_12BIT_CLKDIV_MODE(0x3) | + ADF4350_REG3_12BIT_CSR_EN | + ADF4351_REG3_CHARGE_CANCELLATION_EN | + ADF4351_REG3_ANTI_BACKLASH_3ns_EN | + ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH); + + st->regs[ADF4350_REG4] = + ADF4350_REG4_FEEDBACK_FUND | + ADF4350_REG4_RF_DIV_SEL(st->r4_rf_div_sel) | + ADF4350_REG4_8BIT_BAND_SEL_CLKDIV(band_sel_div) | + ADF4350_REG4_RF_OUT_EN | + (pdata->r4_user_settings & + (ADF4350_REG4_OUTPUT_PWR(0x3) | + ADF4350_REG4_AUX_OUTPUT_PWR(0x3) | + ADF4350_REG4_AUX_OUTPUT_EN | + ADF4350_REG4_AUX_OUTPUT_FUND | + ADF4350_REG4_MUTE_TILL_LOCK_EN)); + + st->regs[ADF4350_REG5] = ADF4350_REG5_LD_PIN_MODE_DIGITAL; + st->freq_req = freq; + + return adf4350_sync_config(st); +} + +static ssize_t adf4350_write(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct adf4350_state *st = iio_priv(indio_dev); + unsigned long long readin; + unsigned long tmp; + int ret; + + ret = kstrtoull(buf, 10, &readin); + if (ret) + return ret; + + mutex_lock(&st->lock); + switch ((u32)private) { + case ADF4350_FREQ: + ret = adf4350_set_freq(st, readin); + break; + case ADF4350_FREQ_REFIN: + if (readin > ADF4350_MAX_FREQ_REFIN) { + ret = -EINVAL; + break; + } + + if (st->clk) { + tmp = clk_round_rate(st->clk, readin); + if (tmp != readin) { + ret = -EINVAL; + break; + } + ret = clk_set_rate(st->clk, tmp); + if (ret < 0) + break; + } + st->clkin = readin; + ret = adf4350_set_freq(st, st->freq_req); + break; + case ADF4350_FREQ_RESOLUTION: + if (readin == 0) + ret = -EINVAL; + else + st->chspc = readin; + break; + case ADF4350_PWRDOWN: + if (readin) + st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN; + else + st->regs[ADF4350_REG2] &= ~ADF4350_REG2_POWER_DOWN_EN; + + adf4350_sync_config(st); + break; + default: + ret = -EINVAL; + } + mutex_unlock(&st->lock); + + return ret ? ret : len; +} + +static ssize_t adf4350_read(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + char *buf) +{ + struct adf4350_state *st = iio_priv(indio_dev); + unsigned long long val; + int ret = 0; + + mutex_lock(&st->lock); + switch ((u32)private) { + case ADF4350_FREQ: + val = (u64)((st->r0_int * st->r1_mod) + st->r0_fract) * + (u64)st->fpfd; + do_div(val, st->r1_mod * (1 << st->r4_rf_div_sel)); + /* PLL unlocked? return error */ + if (st->lock_detect_gpiod) + if (!gpiod_get_value(st->lock_detect_gpiod)) { + dev_dbg(&st->spi->dev, "PLL un-locked\n"); + ret = -EBUSY; + } + break; + case ADF4350_FREQ_REFIN: + if (st->clk) + st->clkin = clk_get_rate(st->clk); + + val = st->clkin; + break; + case ADF4350_FREQ_RESOLUTION: + val = st->chspc; + break; + case ADF4350_PWRDOWN: + val = !!(st->regs[ADF4350_REG2] & ADF4350_REG2_POWER_DOWN_EN); + break; + default: + ret = -EINVAL; + val = 0; + } + mutex_unlock(&st->lock); + + return ret < 0 ? ret : sprintf(buf, "%llu\n", val); +} + +#define _ADF4350_EXT_INFO(_name, _ident) { \ + .name = _name, \ + .read = adf4350_read, \ + .write = adf4350_write, \ + .private = _ident, \ + .shared = IIO_SEPARATE, \ +} + +static const struct iio_chan_spec_ext_info adf4350_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. + */ + _ADF4350_EXT_INFO("frequency", ADF4350_FREQ), + _ADF4350_EXT_INFO("frequency_resolution", ADF4350_FREQ_RESOLUTION), + _ADF4350_EXT_INFO("refin_frequency", ADF4350_FREQ_REFIN), + _ADF4350_EXT_INFO("powerdown", ADF4350_PWRDOWN), + { }, +}; + +static const struct iio_chan_spec adf4350_chan = { + .type = IIO_ALTVOLTAGE, + .indexed = 1, + .output = 1, + .ext_info = adf4350_ext_info, +}; + +static const struct iio_info adf4350_info = { + .debugfs_reg_access = &adf4350_reg_access, +}; + +static struct adf4350_platform_data *adf4350_parse_dt(struct device *dev) +{ + struct adf4350_platform_data *pdata; + unsigned int tmp; + + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return NULL; + + snprintf(pdata->name, sizeof(pdata->name), "%pfw", dev_fwnode(dev)); + + tmp = 10000; + device_property_read_u32(dev, "adi,channel-spacing", &tmp); + pdata->channel_spacing = tmp; + + tmp = 0; + device_property_read_u32(dev, "adi,power-up-frequency", &tmp); + pdata->power_up_frequency = tmp; + + tmp = 0; + device_property_read_u32(dev, "adi,reference-div-factor", &tmp); + pdata->ref_div_factor = tmp; + + pdata->ref_doubler_en = device_property_read_bool(dev, "adi,reference-doubler-enable"); + pdata->ref_div2_en = device_property_read_bool(dev, "adi,reference-div2-enable"); + + /* r2_user_settings */ + pdata->r2_user_settings = 0; + if (device_property_read_bool(dev, "adi,phase-detector-polarity-positive-enable")) + pdata->r2_user_settings |= ADF4350_REG2_PD_POLARITY_POS; + if (device_property_read_bool(dev, "adi,lock-detect-precision-6ns-enable")) + pdata->r2_user_settings |= ADF4350_REG2_LDP_6ns; + if (device_property_read_bool(dev, "adi,lock-detect-function-integer-n-enable")) + pdata->r2_user_settings |= ADF4350_REG2_LDF_INT_N; + + tmp = 2500; + device_property_read_u32(dev, "adi,charge-pump-current", &tmp); + pdata->r2_user_settings |= ADF4350_REG2_CHARGE_PUMP_CURR_uA(tmp); + + tmp = 0; + device_property_read_u32(dev, "adi,muxout-select", &tmp); + pdata->r2_user_settings |= ADF4350_REG2_MUXOUT(tmp); + + if (device_property_read_bool(dev, "adi,low-spur-mode-enable")) + pdata->r2_user_settings |= ADF4350_REG2_NOISE_MODE(0x3); + + /* r3_user_settings */ + + pdata->r3_user_settings = 0; + if (device_property_read_bool(dev, "adi,cycle-slip-reduction-enable")) + pdata->r3_user_settings |= ADF4350_REG3_12BIT_CSR_EN; + if (device_property_read_bool(dev, "adi,charge-cancellation-enable")) + pdata->r3_user_settings |= ADF4351_REG3_CHARGE_CANCELLATION_EN; + if (device_property_read_bool(dev, "adi,anti-backlash-3ns-enable")) + pdata->r3_user_settings |= ADF4351_REG3_ANTI_BACKLASH_3ns_EN; + if (device_property_read_bool(dev, "adi,band-select-clock-mode-high-enable")) + pdata->r3_user_settings |= ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH; + + tmp = 0; + device_property_read_u32(dev, "adi,12bit-clk-divider", &tmp); + pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV(tmp); + + tmp = 0; + device_property_read_u32(dev, "adi,clk-divider-mode", &tmp); + pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV_MODE(tmp); + + /* r4_user_settings */ + + pdata->r4_user_settings = 0; + if (device_property_read_bool(dev, "adi,aux-output-enable")) + pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_EN; + if (device_property_read_bool(dev, "adi,aux-output-fundamental-enable")) + pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_FUND; + if (device_property_read_bool(dev, "adi,mute-till-lock-enable")) + pdata->r4_user_settings |= ADF4350_REG4_MUTE_TILL_LOCK_EN; + + tmp = 0; + device_property_read_u32(dev, "adi,output-power", &tmp); + pdata->r4_user_settings |= ADF4350_REG4_OUTPUT_PWR(tmp); + + tmp = 0; + device_property_read_u32(dev, "adi,aux-output-power", &tmp); + pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_PWR(tmp); + + return pdata; +} + +static void adf4350_power_down(void *data) +{ + struct iio_dev *indio_dev = data; + struct adf4350_state *st = iio_priv(indio_dev); + + st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN; + adf4350_sync_config(st); +} + +static int adf4350_probe(struct spi_device *spi) +{ + struct adf4350_platform_data *pdata; + struct iio_dev *indio_dev; + struct adf4350_state *st; + struct clk *clk = NULL; + int ret; + + if (dev_fwnode(&spi->dev)) { + pdata = adf4350_parse_dt(&spi->dev); + if (pdata == NULL) + return -EINVAL; + } else { + pdata = spi->dev.platform_data; + } + + if (!pdata) { + dev_warn(&spi->dev, "no platform data? using default\n"); + pdata = &default_pdata; + } + + if (!pdata->clkin) { + clk = devm_clk_get_enabled(&spi->dev, "clkin"); + if (IS_ERR(clk)) + return PTR_ERR(clk); + } + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (indio_dev == NULL) + return -ENOMEM; + + st = iio_priv(indio_dev); + + ret = devm_regulator_get_enable(&spi->dev, "vcc"); + if (ret) + return ret; + + st->spi = spi; + st->pdata = pdata; + + indio_dev->name = (pdata->name[0] != 0) ? pdata->name : + spi_get_device_id(spi)->name; + + indio_dev->info = &adf4350_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = &adf4350_chan; + indio_dev->num_channels = 1; + + mutex_init(&st->lock); + + st->chspc = pdata->channel_spacing; + if (clk) { + st->clk = clk; + st->clkin = clk_get_rate(clk); + } else { + st->clkin = pdata->clkin; + } + + st->min_out_freq = spi_get_device_id(spi)->driver_data == 4351 ? + ADF4351_MIN_OUT_FREQ : ADF4350_MIN_OUT_FREQ; + + memset(st->regs_hw, 0xFF, sizeof(st->regs_hw)); + + st->lock_detect_gpiod = devm_gpiod_get_optional(&spi->dev, NULL, + GPIOD_IN); + if (IS_ERR(st->lock_detect_gpiod)) + return PTR_ERR(st->lock_detect_gpiod); + + if (pdata->power_up_frequency) { + ret = adf4350_set_freq(st, pdata->power_up_frequency); + if (ret) + return ret; + } + + ret = devm_add_action_or_reset(&spi->dev, adf4350_power_down, indio_dev); + if (ret) + return dev_err_probe(&spi->dev, ret, + "Failed to add action to managed power down\n"); + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id adf4350_of_match[] = { + { .compatible = "adi,adf4350", }, + { .compatible = "adi,adf4351", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, adf4350_of_match); + +static const struct spi_device_id adf4350_id[] = { + {"adf4350", 4350}, + {"adf4351", 4351}, + {} +}; +MODULE_DEVICE_TABLE(spi, adf4350_id); + +static struct spi_driver adf4350_driver = { + .driver = { + .name = "adf4350", + .of_match_table = adf4350_of_match, + }, + .probe = adf4350_probe, + .id_table = adf4350_id, +}; +module_spi_driver(adf4350_driver); + +MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>"); +MODULE_DESCRIPTION("Analog Devices ADF4350/ADF4351 PLL"); +MODULE_LICENSE("GPL v2"); |