diff options
Diffstat (limited to 'drivers/iio/frequency/adf4350.c')
| -rw-r--r-- | drivers/iio/frequency/adf4350.c | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c new file mode 100644 index 000000000000..59fbb3ae40e7 --- /dev/null +++ b/drivers/iio/frequency/adf4350.c @@ -0,0 +1,480 @@ +/* + * ADF4350/ADF4351 SPI Wideband Synthesizer driver + * + * Copyright 2012 Analog Devices Inc. + * + * Licensed under the GPL-2. + */ + +#include <linux/device.h> +#include <linux/kernel.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/module.h> +#include <linux/gcd.h> +#include <linux/gpio.h> +#include <asm/div64.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 regulator *reg; + struct adf4350_platform_data *pdata; + 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]; + + /* + * DMA (thus cache coherency maintenance) requires the + * transfer buffers to live in their own cache lines. + */ + __be32 val ____cacheline_aligned; +}; + +static struct adf4350_platform_data default_pdata = { + .clkin = 122880000, + .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, + .gpio_lock_detect = -1, +}; + +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(&indio_dev->mlock); + 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(&indio_dev->mlock); + + 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; + 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; + + do { + r_cnt = adf4350_tune_r_cnt(st, r_cnt); + + st->r1_mod = st->fpfd / st->chspc; + while (st->r1_mod > ADF4350_MAX_MODULUS) { + r_cnt = adf4350_tune_r_cnt(st, r_cnt); + st->r1_mod = st->fpfd / st->chspc; + } + + 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(0) | + 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(0x9))); + + 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; + + 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; + int ret; + + ret = kstrtoull(buf, 10, &readin); + if (ret) + return ret; + + mutex_lock(&indio_dev->mlock); + 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; + else + st->clkin = readin; + 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(&indio_dev->mlock); + + 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(&indio_dev->mlock); + 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 (gpio_is_valid(st->pdata->gpio_lock_detect)) + if (!gpio_get_value(st->pdata->gpio_lock_detect)) { + dev_dbg(&st->spi->dev, "PLL un-locked\n"); + ret = -EBUSY; + } + break; + case ADF4350_FREQ_REFIN: + 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; + } + mutex_unlock(&indio_dev->mlock); + + 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, \ +} + +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, + .driver_module = THIS_MODULE, +}; + +static int __devinit adf4350_probe(struct spi_device *spi) +{ + struct adf4350_platform_data *pdata = spi->dev.platform_data; + struct iio_dev *indio_dev; + struct adf4350_state *st; + int ret; + + if (!pdata) { + dev_warn(&spi->dev, "no platform data? using default\n"); + + pdata = &default_pdata; + } + + indio_dev = iio_device_alloc(sizeof(*st)); + if (indio_dev == NULL) + return -ENOMEM; + + st = iio_priv(indio_dev); + + st->reg = regulator_get(&spi->dev, "vcc"); + if (!IS_ERR(st->reg)) { + ret = regulator_enable(st->reg); + if (ret) + goto error_put_reg; + } + + spi_set_drvdata(spi, indio_dev); + st->spi = spi; + st->pdata = pdata; + + indio_dev->dev.parent = &spi->dev; + 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; + + st->chspc = pdata->channel_spacing; + 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)); + + if (gpio_is_valid(pdata->gpio_lock_detect)) { + ret = gpio_request(pdata->gpio_lock_detect, indio_dev->name); + if (ret) { + dev_err(&spi->dev, "fail to request lock detect GPIO-%d", + pdata->gpio_lock_detect); + goto error_disable_reg; + } + gpio_direction_input(pdata->gpio_lock_detect); + } + + if (pdata->power_up_frequency) { + ret = adf4350_set_freq(st, pdata->power_up_frequency); + if (ret) + goto error_free_gpio; + } + + ret = iio_device_register(indio_dev); + if (ret) + goto error_free_gpio; + + return 0; + +error_free_gpio: + if (gpio_is_valid(pdata->gpio_lock_detect)) + gpio_free(pdata->gpio_lock_detect); + +error_disable_reg: + if (!IS_ERR(st->reg)) + regulator_disable(st->reg); +error_put_reg: + if (!IS_ERR(st->reg)) + regulator_put(st->reg); + + iio_device_free(indio_dev); + + return ret; +} + +static int __devexit adf4350_remove(struct spi_device *spi) +{ + struct iio_dev *indio_dev = spi_get_drvdata(spi); + struct adf4350_state *st = iio_priv(indio_dev); + struct regulator *reg = st->reg; + + st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN; + adf4350_sync_config(st); + + iio_device_unregister(indio_dev); + + if (!IS_ERR(reg)) { + regulator_disable(reg); + regulator_put(reg); + } + + if (gpio_is_valid(st->pdata->gpio_lock_detect)) + gpio_free(st->pdata->gpio_lock_detect); + + iio_device_free(indio_dev); + + return 0; +} + +static const struct spi_device_id adf4350_id[] = { + {"adf4350", 4350}, + {"adf4351", 4351}, + {} +}; + +static struct spi_driver adf4350_driver = { + .driver = { + .name = "adf4350", + .owner = THIS_MODULE, + }, + .probe = adf4350_probe, + .remove = __devexit_p(adf4350_remove), + .id_table = adf4350_id, +}; +module_spi_driver(adf4350_driver); + +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); +MODULE_DESCRIPTION("Analog Devices ADF4350/ADF4351 PLL"); +MODULE_LICENSE("GPL v2"); |