linux/drivers/iio/frequency/adf4350.c

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/*
* 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");