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authorMichael Hennerich <michael.hennerich@analog.com>2012-05-29 12:41:20 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-06-04 21:19:40 -0700
commite31166f0fd48478866ee9661c36789126435ebe8 (patch)
treec5a7b345c3331935318376558429ff6e2e092aef /drivers/iio
parentcd1678f963298a9e777f3edb72d28bc18a3a32c2 (diff)
iio: frequency: New driver for Analog Devices ADF4350/ADF4351 Wideband Synthesizers
Changes since V1: Apply Jonathan's review feedback: Introduce and use IIO_ALTVOLTAGE. Fix up comments and documentation. Remove dead code. Reorder some code fragments. Add missing iio_device_free. Convert to new API. Fix-up out of staging includes. Removed pll_locked attribute. Changes since V2: Use module_spi_driver. adf4350_remove: move gpio_free after regulator. target patch to drivers/iio Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/iio')
-rw-r--r--drivers/iio/frequency/Kconfig18
-rw-r--r--drivers/iio/frequency/Makefile1
-rw-r--r--drivers/iio/frequency/adf4350.c478
3 files changed, 497 insertions, 0 deletions
diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig
index 0458c92464a..6aaa33ef454 100644
--- a/drivers/iio/frequency/Kconfig
+++ b/drivers/iio/frequency/Kconfig
@@ -20,4 +20,22 @@ config AD9523
module will be called ad9523.
endmenu
+
+#
+# Phase-Locked Loop (PLL) frequency synthesizers
+#
+
+menu "Phase-Locked Loop (PLL) frequency synthesizers"
+
+config ADF4350
+ tristate "Analog Devices ADF4350/ADF4351 Wideband Synthesizers"
+ depends on SPI
+ help
+ Say yes here to build support for Analog Devices ADF4350/ADF4351
+ Wideband Synthesizers. The driver provides direct access via sysfs.
+
+ To compile this driver as a module, choose M here: the
+ module will be called adf4350.
+
+endmenu
endmenu
diff --git a/drivers/iio/frequency/Makefile b/drivers/iio/frequency/Makefile
index 1b5b22417da..00d26e5d1dc 100644
--- a/drivers/iio/frequency/Makefile
+++ b/drivers/iio/frequency/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_AD9523) += ad9523.o
+obj-$(CONFIG_ADF4350) += adf4350.o
diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c
new file mode 100644
index 00000000000..fd4c8501aba
--- /dev/null
+++ b/drivers/iio/frequency/adf4350.c
@@ -0,0 +1,478 @@
+/*
+ * 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 = -ENODEV;
+ }
+ 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;
+ }
+ 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");