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path: root/drivers/iio/dac/ad5592r-base.c
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Diffstat (limited to 'drivers/iio/dac/ad5592r-base.c')
-rw-r--r--drivers/iio/dac/ad5592r-base.c691
1 files changed, 691 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5592r-base.c b/drivers/iio/dac/ad5592r-base.c
new file mode 100644
index 000000000000..948f600e7059
--- /dev/null
+++ b/drivers/iio/dac/ad5592r-base.c
@@ -0,0 +1,691 @@
+/*
+ * AD5592R Digital <-> Analog converters driver
+ *
+ * Copyright 2014-2016 Analog Devices Inc.
+ * Author: Paul Cercueil <paul.cercueil@analog.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio.h>
+#include <linux/property.h>
+
+#include <dt-bindings/iio/adi,ad5592r.h>
+
+#include "ad5592r-base.h"
+
+static int ad5592r_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct ad5592r_state *st = gpiochip_get_data(chip);
+ int ret = 0;
+ u8 val;
+
+ mutex_lock(&st->gpio_lock);
+
+ if (st->gpio_out & BIT(offset))
+ val = st->gpio_val;
+ else
+ ret = st->ops->gpio_read(st, &val);
+
+ mutex_unlock(&st->gpio_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return !!(val & BIT(offset));
+}
+
+static void ad5592r_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct ad5592r_state *st = gpiochip_get_data(chip);
+
+ mutex_lock(&st->gpio_lock);
+
+ if (value)
+ st->gpio_val |= BIT(offset);
+ else
+ st->gpio_val &= ~BIT(offset);
+
+ st->ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
+
+ mutex_unlock(&st->gpio_lock);
+}
+
+static int ad5592r_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct ad5592r_state *st = gpiochip_get_data(chip);
+ int ret;
+
+ mutex_lock(&st->gpio_lock);
+
+ st->gpio_out &= ~BIT(offset);
+ st->gpio_in |= BIT(offset);
+
+ ret = st->ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
+ if (ret < 0)
+ goto err_unlock;
+
+ ret = st->ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
+
+err_unlock:
+ mutex_unlock(&st->gpio_lock);
+
+ return ret;
+}
+
+static int ad5592r_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct ad5592r_state *st = gpiochip_get_data(chip);
+ int ret;
+
+ mutex_lock(&st->gpio_lock);
+
+ if (value)
+ st->gpio_val |= BIT(offset);
+ else
+ st->gpio_val &= ~BIT(offset);
+
+ st->gpio_in &= ~BIT(offset);
+ st->gpio_out |= BIT(offset);
+
+ ret = st->ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
+ if (ret < 0)
+ goto err_unlock;
+
+ ret = st->ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
+ if (ret < 0)
+ goto err_unlock;
+
+ ret = st->ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
+
+err_unlock:
+ mutex_unlock(&st->gpio_lock);
+
+ return ret;
+}
+
+static int ad5592r_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+ struct ad5592r_state *st = gpiochip_get_data(chip);
+
+ if (!(st->gpio_map & BIT(offset))) {
+ dev_err(st->dev, "GPIO %d is reserved by alternate function\n",
+ offset);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int ad5592r_gpio_init(struct ad5592r_state *st)
+{
+ if (!st->gpio_map)
+ return 0;
+
+ st->gpiochip.label = dev_name(st->dev);
+ st->gpiochip.base = -1;
+ st->gpiochip.ngpio = 8;
+ st->gpiochip.parent = st->dev;
+ st->gpiochip.can_sleep = true;
+ st->gpiochip.direction_input = ad5592r_gpio_direction_input;
+ st->gpiochip.direction_output = ad5592r_gpio_direction_output;
+ st->gpiochip.get = ad5592r_gpio_get;
+ st->gpiochip.set = ad5592r_gpio_set;
+ st->gpiochip.request = ad5592r_gpio_request;
+ st->gpiochip.owner = THIS_MODULE;
+
+ mutex_init(&st->gpio_lock);
+
+ return gpiochip_add_data(&st->gpiochip, st);
+}
+
+static void ad5592r_gpio_cleanup(struct ad5592r_state *st)
+{
+ if (st->gpio_map)
+ gpiochip_remove(&st->gpiochip);
+}
+
+static int ad5592r_reset(struct ad5592r_state *st)
+{
+ struct gpio_desc *gpio;
+ struct iio_dev *iio_dev = iio_priv_to_dev(st);
+
+ gpio = devm_gpiod_get_optional(st->dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(gpio))
+ return PTR_ERR(gpio);
+
+ if (gpio) {
+ udelay(1);
+ gpiod_set_value(gpio, 1);
+ } else {
+ mutex_lock(&iio_dev->mlock);
+ /* Writing this magic value resets the device */
+ st->ops->reg_write(st, AD5592R_REG_RESET, 0xdac);
+ mutex_unlock(&iio_dev->mlock);
+ }
+
+ udelay(250);
+
+ return 0;
+}
+
+static int ad5592r_get_vref(struct ad5592r_state *st)
+{
+ int ret;
+
+ if (st->reg) {
+ ret = regulator_get_voltage(st->reg);
+ if (ret < 0)
+ return ret;
+
+ return ret / 1000;
+ } else {
+ return 2500;
+ }
+}
+
+static int ad5592r_set_channel_modes(struct ad5592r_state *st)
+{
+ const struct ad5592r_rw_ops *ops = st->ops;
+ int ret;
+ unsigned i;
+ struct iio_dev *iio_dev = iio_priv_to_dev(st);
+ u8 pulldown = 0, tristate = 0, dac = 0, adc = 0;
+ u16 read_back;
+
+ for (i = 0; i < st->num_channels; i++) {
+ switch (st->channel_modes[i]) {
+ case CH_MODE_DAC:
+ dac |= BIT(i);
+ break;
+
+ case CH_MODE_ADC:
+ adc |= BIT(i);
+ break;
+
+ case CH_MODE_DAC_AND_ADC:
+ dac |= BIT(i);
+ adc |= BIT(i);
+ break;
+
+ case CH_MODE_GPIO:
+ st->gpio_map |= BIT(i);
+ st->gpio_in |= BIT(i); /* Default to input */
+ break;
+
+ case CH_MODE_UNUSED:
+ /* fall-through */
+ default:
+ switch (st->channel_offstate[i]) {
+ case CH_OFFSTATE_OUT_TRISTATE:
+ tristate |= BIT(i);
+ break;
+
+ case CH_OFFSTATE_OUT_LOW:
+ st->gpio_out |= BIT(i);
+ break;
+
+ case CH_OFFSTATE_OUT_HIGH:
+ st->gpio_out |= BIT(i);
+ st->gpio_val |= BIT(i);
+ break;
+
+ case CH_OFFSTATE_PULLDOWN:
+ /* fall-through */
+ default:
+ pulldown |= BIT(i);
+ break;
+ }
+ }
+ }
+
+ mutex_lock(&iio_dev->mlock);
+
+ /* Pull down unused pins to GND */
+ ret = ops->reg_write(st, AD5592R_REG_PULLDOWN, pulldown);
+ if (ret)
+ goto err_unlock;
+
+ ret = ops->reg_write(st, AD5592R_REG_TRISTATE, tristate);
+ if (ret)
+ goto err_unlock;
+
+ /* Configure pins that we use */
+ ret = ops->reg_write(st, AD5592R_REG_DAC_EN, dac);
+ if (ret)
+ goto err_unlock;
+
+ ret = ops->reg_write(st, AD5592R_REG_ADC_EN, adc);
+ if (ret)
+ goto err_unlock;
+
+ ret = ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
+ if (ret)
+ goto err_unlock;
+
+ ret = ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
+ if (ret)
+ goto err_unlock;
+
+ ret = ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
+ if (ret)
+ goto err_unlock;
+
+ /* Verify that we can read back at least one register */
+ ret = ops->reg_read(st, AD5592R_REG_ADC_EN, &read_back);
+ if (!ret && (read_back & 0xff) != adc)
+ ret = -EIO;
+
+err_unlock:
+ mutex_unlock(&iio_dev->mlock);
+ return ret;
+}
+
+static int ad5592r_reset_channel_modes(struct ad5592r_state *st)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(st->channel_modes); i++)
+ st->channel_modes[i] = CH_MODE_UNUSED;
+
+ return ad5592r_set_channel_modes(st);
+}
+
+static int ad5592r_write_raw(struct iio_dev *iio_dev,
+ struct iio_chan_spec const *chan, int val, int val2, long mask)
+{
+ struct ad5592r_state *st = iio_priv(iio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+
+ if (val >= (1 << chan->scan_type.realbits) || val < 0)
+ return -EINVAL;
+
+ if (!chan->output)
+ return -EINVAL;
+
+ mutex_lock(&iio_dev->mlock);
+ ret = st->ops->write_dac(st, chan->channel, val);
+ if (!ret)
+ st->cached_dac[chan->channel] = val;
+ mutex_unlock(&iio_dev->mlock);
+ return ret;
+ case IIO_CHAN_INFO_SCALE:
+ if (chan->type == IIO_VOLTAGE) {
+ bool gain;
+
+ if (val == st->scale_avail[0][0] &&
+ val2 == st->scale_avail[0][1])
+ gain = false;
+ else if (val == st->scale_avail[1][0] &&
+ val2 == st->scale_avail[1][1])
+ gain = true;
+ else
+ return -EINVAL;
+
+ mutex_lock(&iio_dev->mlock);
+
+ ret = st->ops->reg_read(st, AD5592R_REG_CTRL,
+ &st->cached_gp_ctrl);
+ if (ret < 0) {
+ mutex_unlock(&iio_dev->mlock);
+ return ret;
+ }
+
+ if (chan->output) {
+ if (gain)
+ st->cached_gp_ctrl |=
+ AD5592R_REG_CTRL_DAC_RANGE;
+ else
+ st->cached_gp_ctrl &=
+ ~AD5592R_REG_CTRL_DAC_RANGE;
+ } else {
+ if (gain)
+ st->cached_gp_ctrl |=
+ AD5592R_REG_CTRL_ADC_RANGE;
+ else
+ st->cached_gp_ctrl &=
+ ~AD5592R_REG_CTRL_ADC_RANGE;
+ }
+
+ ret = st->ops->reg_write(st, AD5592R_REG_CTRL,
+ st->cached_gp_ctrl);
+ mutex_unlock(&iio_dev->mlock);
+
+ return ret;
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ad5592r_read_raw(struct iio_dev *iio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long m)
+{
+ struct ad5592r_state *st = iio_priv(iio_dev);
+ u16 read_val;
+ int ret;
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&iio_dev->mlock);
+
+ if (!chan->output) {
+ ret = st->ops->read_adc(st, chan->channel, &read_val);
+ if (ret)
+ goto unlock;
+
+ if ((read_val >> 12 & 0x7) != (chan->channel & 0x7)) {
+ dev_err(st->dev, "Error while reading channel %u\n",
+ chan->channel);
+ ret = -EIO;
+ goto unlock;
+ }
+
+ read_val &= GENMASK(11, 0);
+
+ } else {
+ read_val = st->cached_dac[chan->channel];
+ }
+
+ dev_dbg(st->dev, "Channel %u read: 0x%04hX\n",
+ chan->channel, read_val);
+
+ *val = (int) read_val;
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_CHAN_INFO_SCALE:
+ *val = ad5592r_get_vref(st);
+
+ if (chan->type == IIO_TEMP) {
+ s64 tmp = *val * (3767897513LL / 25LL);
+ *val = div_s64_rem(tmp, 1000000000LL, val2);
+
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ } else {
+ int mult;
+
+ mutex_lock(&iio_dev->mlock);
+
+ if (chan->output)
+ mult = !!(st->cached_gp_ctrl &
+ AD5592R_REG_CTRL_DAC_RANGE);
+ else
+ mult = !!(st->cached_gp_ctrl &
+ AD5592R_REG_CTRL_ADC_RANGE);
+
+ *val *= ++mult;
+
+ *val2 = chan->scan_type.realbits;
+ ret = IIO_VAL_FRACTIONAL_LOG2;
+ }
+ break;
+ case IIO_CHAN_INFO_OFFSET:
+ ret = ad5592r_get_vref(st);
+
+ mutex_lock(&iio_dev->mlock);
+
+ if (st->cached_gp_ctrl & AD5592R_REG_CTRL_ADC_RANGE)
+ *val = (-34365 * 25) / ret;
+ else
+ *val = (-75365 * 25) / ret;
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+unlock:
+ mutex_unlock(&iio_dev->mlock);
+ return ret;
+}
+
+static int ad5592r_write_raw_get_fmt(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ return IIO_VAL_INT_PLUS_NANO;
+
+ default:
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info ad5592r_info = {
+ .read_raw = ad5592r_read_raw,
+ .write_raw = ad5592r_write_raw,
+ .write_raw_get_fmt = ad5592r_write_raw_get_fmt,
+ .driver_module = THIS_MODULE,
+};
+
+static ssize_t ad5592r_show_scale_available(struct iio_dev *iio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ char *buf)
+{
+ struct ad5592r_state *st = iio_priv(iio_dev);
+
+ return sprintf(buf, "%d.%09u %d.%09u\n",
+ st->scale_avail[0][0], st->scale_avail[0][1],
+ st->scale_avail[1][0], st->scale_avail[1][1]);
+}
+
+static struct iio_chan_spec_ext_info ad5592r_ext_info[] = {
+ {
+ .name = "scale_available",
+ .read = ad5592r_show_scale_available,
+ .shared = true,
+ },
+ {},
+};
+
+static void ad5592r_setup_channel(struct iio_dev *iio_dev,
+ struct iio_chan_spec *chan, bool output, unsigned id)
+{
+ chan->type = IIO_VOLTAGE;
+ chan->indexed = 1;
+ chan->output = output;
+ chan->channel = id;
+ chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
+ chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
+ chan->scan_type.sign = 'u';
+ chan->scan_type.realbits = 12;
+ chan->scan_type.storagebits = 16;
+ chan->ext_info = ad5592r_ext_info;
+}
+
+static int ad5592r_alloc_channels(struct ad5592r_state *st)
+{
+ unsigned i, curr_channel = 0,
+ num_channels = st->num_channels;
+ struct iio_dev *iio_dev = iio_priv_to_dev(st);
+ struct iio_chan_spec *channels;
+ struct fwnode_handle *child;
+ u32 reg, tmp;
+ int ret;
+
+ device_for_each_child_node(st->dev, child) {
+ ret = fwnode_property_read_u32(child, "reg", &reg);
+ if (ret || reg > ARRAY_SIZE(st->channel_modes))
+ continue;
+
+ ret = fwnode_property_read_u32(child, "adi,mode", &tmp);
+ if (!ret)
+ st->channel_modes[reg] = tmp;
+
+ fwnode_property_read_u32(child, "adi,off-state", &tmp);
+ if (!ret)
+ st->channel_offstate[reg] = tmp;
+ }
+
+ channels = devm_kzalloc(st->dev,
+ (1 + 2 * num_channels) * sizeof(*channels), GFP_KERNEL);
+ if (!channels)
+ return -ENOMEM;
+
+ for (i = 0; i < num_channels; i++) {
+ switch (st->channel_modes[i]) {
+ case CH_MODE_DAC:
+ ad5592r_setup_channel(iio_dev, &channels[curr_channel],
+ true, i);
+ curr_channel++;
+ break;
+
+ case CH_MODE_ADC:
+ ad5592r_setup_channel(iio_dev, &channels[curr_channel],
+ false, i);
+ curr_channel++;
+ break;
+
+ case CH_MODE_DAC_AND_ADC:
+ ad5592r_setup_channel(iio_dev, &channels[curr_channel],
+ true, i);
+ curr_channel++;
+ ad5592r_setup_channel(iio_dev, &channels[curr_channel],
+ false, i);
+ curr_channel++;
+ break;
+
+ default:
+ continue;
+ }
+ }
+
+ channels[curr_channel].type = IIO_TEMP;
+ channels[curr_channel].channel = 8;
+ channels[curr_channel].info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET);
+ curr_channel++;
+
+ iio_dev->num_channels = curr_channel;
+ iio_dev->channels = channels;
+
+ return 0;
+}
+
+static void ad5592r_init_scales(struct ad5592r_state *st, int vref_mV)
+{
+ s64 tmp = (s64)vref_mV * 1000000000LL >> 12;
+
+ st->scale_avail[0][0] =
+ div_s64_rem(tmp, 1000000000LL, &st->scale_avail[0][1]);
+ st->scale_avail[1][0] =
+ div_s64_rem(tmp * 2, 1000000000LL, &st->scale_avail[1][1]);
+}
+
+int ad5592r_probe(struct device *dev, const char *name,
+ const struct ad5592r_rw_ops *ops)
+{
+ struct iio_dev *iio_dev;
+ struct ad5592r_state *st;
+ int ret;
+
+ iio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+ if (!iio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(iio_dev);
+ st->dev = dev;
+ st->ops = ops;
+ st->num_channels = 8;
+ dev_set_drvdata(dev, iio_dev);
+
+ st->reg = devm_regulator_get_optional(dev, "vref");
+ if (IS_ERR(st->reg)) {
+ if ((PTR_ERR(st->reg) != -ENODEV) && dev->of_node)
+ return PTR_ERR(st->reg);
+
+ st->reg = NULL;
+ } else {
+ ret = regulator_enable(st->reg);
+ if (ret)
+ return ret;
+ }
+
+ iio_dev->dev.parent = dev;
+ iio_dev->name = name;
+ iio_dev->info = &ad5592r_info;
+ iio_dev->modes = INDIO_DIRECT_MODE;
+
+ ad5592r_init_scales(st, ad5592r_get_vref(st));
+
+ ret = ad5592r_reset(st);
+ if (ret)
+ goto error_disable_reg;
+
+ ret = ops->reg_write(st, AD5592R_REG_PD,
+ (st->reg == NULL) ? AD5592R_REG_PD_EN_REF : 0);
+ if (ret)
+ goto error_disable_reg;
+
+ ret = ad5592r_alloc_channels(st);
+ if (ret)
+ goto error_disable_reg;
+
+ ret = ad5592r_set_channel_modes(st);
+ if (ret)
+ goto error_reset_ch_modes;
+
+ ret = iio_device_register(iio_dev);
+ if (ret)
+ goto error_reset_ch_modes;
+
+ ret = ad5592r_gpio_init(st);
+ if (ret)
+ goto error_dev_unregister;
+
+ return 0;
+
+error_dev_unregister:
+ iio_device_unregister(iio_dev);
+
+error_reset_ch_modes:
+ ad5592r_reset_channel_modes(st);
+
+error_disable_reg:
+ if (st->reg)
+ regulator_disable(st->reg);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ad5592r_probe);
+
+int ad5592r_remove(struct device *dev)
+{
+ struct iio_dev *iio_dev = dev_get_drvdata(dev);
+ struct ad5592r_state *st = iio_priv(iio_dev);
+
+ iio_device_unregister(iio_dev);
+ ad5592r_reset_channel_modes(st);
+ ad5592r_gpio_cleanup(st);
+
+ if (st->reg)
+ regulator_disable(st->reg);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ad5592r_remove);
+
+MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
+MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-20 03:50:07 +0300