--- /dev/null
+/*
+ * AD5504, AD5501 High Voltage Digital to Analog Converter
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+#include <linux/bitops.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+#include <linux/iio/dac/ad5504.h>
+
+#define AD5504_RES_MASK GENMASK(11, 0)
+#define AD5504_CMD_READ BIT(15)
+#define AD5504_CMD_WRITE 0
+#define AD5504_ADDR(addr) ((addr) << 12)
+
+/* Registers */
+#define AD5504_ADDR_NOOP 0
+#define AD5504_ADDR_DAC(x) ((x) + 1)
+#define AD5504_ADDR_ALL_DAC 5
+#define AD5504_ADDR_CTRL 7
+
+/* Control Register */
+#define AD5504_DAC_PWR(ch) ((ch) << 2)
+#define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6)
+#define AD5504_DAC_PWRDN_20K 0
+#define AD5504_DAC_PWRDN_3STATE 1
+
+/**
+ * struct ad5446_state - driver instance specific data
+ * @spi: spi_device
+ * @reg: supply regulator
+ * @vref_mv: actual reference voltage used
+ * @pwr_down_mask power down mask
+ * @pwr_down_mode current power down mode
+ * @data: transfer buffer
+ */
+struct ad5504_state {
+ struct spi_device *spi;
+ struct regulator *reg;
+ unsigned short vref_mv;
+ unsigned pwr_down_mask;
+ unsigned pwr_down_mode;
+
+ __be16 data[2] ____cacheline_aligned;
+};
+
+/**
+ * ad5504_supported_device_ids:
+ */
+
+enum ad5504_supported_device_ids {
+ ID_AD5504,
+ ID_AD5501,
+};
+
+static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val)
+{
+ st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) |
+ (val & AD5504_RES_MASK));
+
+ return spi_write(st->spi, &st->data[0], 2);
+}
+
+static int ad5504_spi_read(struct ad5504_state *st, u8 addr)
+{
+ int ret;
+ struct spi_transfer t = {
+ .tx_buf = &st->data[0],
+ .rx_buf = &st->data[1],
+ .len = 2,
+ };
+
+ st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));
+ ret = spi_sync_transfer(st->spi, &t, 1);
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(st->data[1]) & AD5504_RES_MASK;
+}
+
+static int ad5504_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ struct ad5504_state *st = iio_priv(indio_dev);
+ int ret;
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ ret = ad5504_spi_read(st, chan->address);
+ if (ret < 0)
+ return ret;
+
+ *val = ret;
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = st->vref_mv;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ }
+ return -EINVAL;
+}
+
+static int ad5504_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad5504_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (val >= (1 << chan->scan_type.realbits) || val < 0)
+ return -EINVAL;
+
+ return ad5504_spi_write(st, chan->address, val);
+ default:
+ return -EINVAL;
+ }
+}
+
+static const char * const ad5504_powerdown_modes[] = {
+ "20kohm_to_gnd",
+ "three_state",
+};
+
+static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct ad5504_state *st = iio_priv(indio_dev);
+
+ return st->pwr_down_mode;
+}
+
+static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, unsigned int mode)
+{
+ struct ad5504_state *st = iio_priv(indio_dev);
+
+ st->pwr_down_mode = mode;
+
+ return 0;
+}
+
+static const struct iio_enum ad5504_powerdown_mode_enum = {
+ .items = ad5504_powerdown_modes,
+ .num_items = ARRAY_SIZE(ad5504_powerdown_modes),
+ .get = ad5504_get_powerdown_mode,
+ .set = ad5504_set_powerdown_mode,
+};
+
+static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,
+ uintptr_t private, const struct iio_chan_spec *chan, char *buf)
+{
+ struct ad5504_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n",
+ !(st->pwr_down_mask & (1 << chan->channel)));
+}
+
+static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev,
+ uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
+ size_t len)
+{
+ bool pwr_down;
+ int ret;
+ struct ad5504_state *st = iio_priv(indio_dev);
+
+ ret = strtobool(buf, &pwr_down);
+ if (ret)
+ return ret;
+
+ if (pwr_down)
+ st->pwr_down_mask |= (1 << chan->channel);
+ else
+ st->pwr_down_mask &= ~(1 << chan->channel);
+
+ ret = ad5504_spi_write(st, AD5504_ADDR_CTRL,
+ AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |
+ AD5504_DAC_PWR(st->pwr_down_mask));
+
+ /* writes to the CTRL register must be followed by a NOOP */
+ ad5504_spi_write(st, AD5504_ADDR_NOOP, 0);
+
+ return ret ? ret : len;
+}
+
+static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");
+static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");
+
+static struct attribute *ad5504_ev_attributes[] = {
+ &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,
+ &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,
+ NULL,
+};
+
+static struct attribute_group ad5504_ev_attribute_group = {
+ .attrs = ad5504_ev_attributes,
+ .name = "events",
+};
+
+static irqreturn_t ad5504_event_handler(int irq, void *private)
+{
+ iio_push_event(private,
+ IIO_UNMOD_EVENT_CODE(IIO_TEMP,
+ 0,
+ IIO_EV_TYPE_THRESH,
+ IIO_EV_DIR_RISING),
+ iio_get_time_ns());
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_info ad5504_info = {
+ .write_raw = ad5504_write_raw,
+ .read_raw = ad5504_read_raw,
+ .event_attrs = &ad5504_ev_attribute_group,
+ .driver_module = THIS_MODULE,
+};
+
+static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
+ {
+ .name = "powerdown",
+ .read = ad5504_read_dac_powerdown,
+ .write = ad5504_write_dac_powerdown,
+ .shared = IIO_SEPARATE,
+ },
+ IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
+ &ad5504_powerdown_mode_enum),
+ IIO_ENUM_AVAILABLE("powerdown_mode", &ad5504_powerdown_mode_enum),
+ { },
+};
+
+#define AD5504_CHANNEL(_chan) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .output = 1, \
+ .channel = (_chan), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .address = AD5504_ADDR_DAC(_chan), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 12, \
+ .storagebits = 16, \
+ }, \
+ .ext_info = ad5504_ext_info, \
+}
+
+static const struct iio_chan_spec ad5504_channels[] = {
+ AD5504_CHANNEL(0),
+ AD5504_CHANNEL(1),
+ AD5504_CHANNEL(2),
+ AD5504_CHANNEL(3),
+};
+
+static int ad5504_probe(struct spi_device *spi)
+{
+ struct ad5504_platform_data *pdata = spi->dev.platform_data;
+ struct iio_dev *indio_dev;
+ struct ad5504_state *st;
+ struct regulator *reg;
+ int ret, voltage_uv = 0;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+ reg = devm_regulator_get(&spi->dev, "vcc");
+ if (!IS_ERR(reg)) {
+ ret = regulator_enable(reg);
+ if (ret)
+ return ret;
+
+ ret = regulator_get_voltage(reg);
+ if (ret < 0)
+ goto error_disable_reg;
+
+ voltage_uv = ret;
+ }
+
+ spi_set_drvdata(spi, indio_dev);
+ st = iio_priv(indio_dev);
+ if (voltage_uv)
+ st->vref_mv = voltage_uv / 1000;
+ else if (pdata)
+ st->vref_mv = pdata->vref_mv;
+ else
+ dev_warn(&spi->dev, "reference voltage unspecified\n");
+
+ st->reg = reg;
+ st->spi = spi;
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(st->spi)->name;
+ indio_dev->info = &ad5504_info;
+ if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)
+ indio_dev->num_channels = 1;
+ else
+ indio_dev->num_channels = 4;
+ indio_dev->channels = ad5504_channels;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ if (spi->irq) {
+ ret = devm_request_threaded_irq(&spi->dev, spi->irq,
+ NULL,
+ &ad5504_event_handler,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ spi_get_device_id(st->spi)->name,
+ indio_dev);
+ if (ret)
+ goto error_disable_reg;
+ }
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_disable_reg;
+
+ return 0;
+
+error_disable_reg:
+ if (!IS_ERR(reg))
+ regulator_disable(reg);
+
+ return ret;
+}
+
+static int ad5504_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ad5504_state *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ if (!IS_ERR(st->reg))
+ regulator_disable(st->reg);
+
+ return 0;
+}
+
+static const struct spi_device_id ad5504_id[] = {
+ {"ad5504", ID_AD5504},
+ {"ad5501", ID_AD5501},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad5504_id);
+
+static struct spi_driver ad5504_driver = {
+ .driver = {
+ .name = "ad5504",
+ .owner = THIS_MODULE,
+ },
+ .probe = ad5504_probe,
+ .remove = ad5504_remove,
+ .id_table = ad5504_id,
+};
+module_spi_driver(ad5504_driver);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff