--- /dev/null
+/*
+ * Analog devices AD5360, AD5361, AD5362, AD5363, AD5370, AD5371, AD5373
+ * multi-channel Digital to Analog Converters driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.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/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define AD5360_CMD(x) ((x) << 22)
+#define AD5360_ADDR(x) ((x) << 16)
+
+#define AD5360_READBACK_TYPE(x) ((x) << 13)
+#define AD5360_READBACK_ADDR(x) ((x) << 7)
+
+#define AD5360_CHAN_ADDR(chan) ((chan) + 0x8)
+
+#define AD5360_CMD_WRITE_DATA 0x3
+#define AD5360_CMD_WRITE_OFFSET 0x2
+#define AD5360_CMD_WRITE_GAIN 0x1
+#define AD5360_CMD_SPECIAL_FUNCTION 0x0
+
+/* Special function register addresses */
+#define AD5360_REG_SF_NOP 0x0
+#define AD5360_REG_SF_CTRL 0x1
+#define AD5360_REG_SF_OFS(x) (0x2 + (x))
+#define AD5360_REG_SF_READBACK 0x5
+
+#define AD5360_SF_CTRL_PWR_DOWN BIT(0)
+
+#define AD5360_READBACK_X1A 0x0
+#define AD5360_READBACK_X1B 0x1
+#define AD5360_READBACK_OFFSET 0x2
+#define AD5360_READBACK_GAIN 0x3
+#define AD5360_READBACK_SF 0x4
+
+
+/**
+ * struct ad5360_chip_info - chip specific information
+ * @channel_template: channel specification template
+ * @num_channels: number of channels
+ * @channels_per_group: number of channels per group
+ * @num_vrefs: number of vref supplies for the chip
+*/
+
+struct ad5360_chip_info {
+ struct iio_chan_spec channel_template;
+ unsigned int num_channels;
+ unsigned int channels_per_group;
+ unsigned int num_vrefs;
+};
+
+/**
+ * struct ad5360_state - driver instance specific data
+ * @spi: spi_device
+ * @chip_info: chip model specific constants, available modes etc
+ * @vref_reg: vref supply regulators
+ * @ctrl: control register cache
+ * @data: spi transfer buffers
+ */
+
+struct ad5360_state {
+ struct spi_device *spi;
+ const struct ad5360_chip_info *chip_info;
+ struct regulator_bulk_data vref_reg[3];
+ unsigned int ctrl;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ union {
+ __be32 d32;
+ u8 d8[4];
+ } data[2] ____cacheline_aligned;
+};
+
+enum ad5360_type {
+ ID_AD5360,
+ ID_AD5361,
+ ID_AD5362,
+ ID_AD5363,
+ ID_AD5370,
+ ID_AD5371,
+ ID_AD5372,
+ ID_AD5373,
+};
+
+#define AD5360_CHANNEL(bits) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .output = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_OFFSET) | \
+ BIT(IIO_CHAN_INFO_CALIBSCALE) | \
+ BIT(IIO_CHAN_INFO_CALIBBIAS), \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = (bits), \
+ .storagebits = 16, \
+ .shift = 16 - (bits), \
+ }, \
+}
+
+static const struct ad5360_chip_info ad5360_chip_info_tbl[] = {
+ [ID_AD5360] = {
+ .channel_template = AD5360_CHANNEL(16),
+ .num_channels = 16,
+ .channels_per_group = 8,
+ .num_vrefs = 2,
+ },
+ [ID_AD5361] = {
+ .channel_template = AD5360_CHANNEL(14),
+ .num_channels = 16,
+ .channels_per_group = 8,
+ .num_vrefs = 2,
+ },
+ [ID_AD5362] = {
+ .channel_template = AD5360_CHANNEL(16),
+ .num_channels = 8,
+ .channels_per_group = 4,
+ .num_vrefs = 2,
+ },
+ [ID_AD5363] = {
+ .channel_template = AD5360_CHANNEL(14),
+ .num_channels = 8,
+ .channels_per_group = 4,
+ .num_vrefs = 2,
+ },
+ [ID_AD5370] = {
+ .channel_template = AD5360_CHANNEL(16),
+ .num_channels = 40,
+ .channels_per_group = 8,
+ .num_vrefs = 2,
+ },
+ [ID_AD5371] = {
+ .channel_template = AD5360_CHANNEL(14),
+ .num_channels = 40,
+ .channels_per_group = 8,
+ .num_vrefs = 3,
+ },
+ [ID_AD5372] = {
+ .channel_template = AD5360_CHANNEL(16),
+ .num_channels = 32,
+ .channels_per_group = 8,
+ .num_vrefs = 2,
+ },
+ [ID_AD5373] = {
+ .channel_template = AD5360_CHANNEL(14),
+ .num_channels = 32,
+ .channels_per_group = 8,
+ .num_vrefs = 2,
+ },
+};
+
+static unsigned int ad5360_get_channel_vref_index(struct ad5360_state *st,
+ unsigned int channel)
+{
+ unsigned int i;
+
+ /* The first groups have their own vref, while the remaining groups
+ * share the last vref */
+ i = channel / st->chip_info->channels_per_group;
+ if (i >= st->chip_info->num_vrefs)
+ i = st->chip_info->num_vrefs - 1;
+
+ return i;
+}
+
+static int ad5360_get_channel_vref(struct ad5360_state *st,
+ unsigned int channel)
+{
+ unsigned int i = ad5360_get_channel_vref_index(st, channel);
+
+ return regulator_get_voltage(st->vref_reg[i].consumer);
+}
+
+
+static int ad5360_write_unlocked(struct iio_dev *indio_dev,
+ unsigned int cmd, unsigned int addr, unsigned int val,
+ unsigned int shift)
+{
+ struct ad5360_state *st = iio_priv(indio_dev);
+
+ val <<= shift;
+ val |= AD5360_CMD(cmd) | AD5360_ADDR(addr);
+ st->data[0].d32 = cpu_to_be32(val);
+
+ return spi_write(st->spi, &st->data[0].d8[1], 3);
+}
+
+static int ad5360_write(struct iio_dev *indio_dev, unsigned int cmd,
+ unsigned int addr, unsigned int val, unsigned int shift)
+{
+ int ret;
+
+ mutex_lock(&indio_dev->mlock);
+ ret = ad5360_write_unlocked(indio_dev, cmd, addr, val, shift);
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static int ad5360_read(struct iio_dev *indio_dev, unsigned int type,
+ unsigned int addr)
+{
+ struct ad5360_state *st = iio_priv(indio_dev);
+ int ret;
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->data[0].d8[1],
+ .len = 3,
+ .cs_change = 1,
+ }, {
+ .rx_buf = &st->data[1].d8[1],
+ .len = 3,
+ },
+ };
+
+ mutex_lock(&indio_dev->mlock);
+
+ st->data[0].d32 = cpu_to_be32(AD5360_CMD(AD5360_CMD_SPECIAL_FUNCTION) |
+ AD5360_ADDR(AD5360_REG_SF_READBACK) |
+ AD5360_READBACK_TYPE(type) |
+ AD5360_READBACK_ADDR(addr));
+
+ ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
+ if (ret >= 0)
+ ret = be32_to_cpu(st->data[1].d32) & 0xffff;
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static ssize_t ad5360_read_dac_powerdown(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ad5360_state *st = iio_priv(indio_dev);
+
+ return sprintf(buf, "%d\n", (bool)(st->ctrl & AD5360_SF_CTRL_PWR_DOWN));
+}
+
+static int ad5360_update_ctrl(struct iio_dev *indio_dev, unsigned int set,
+ unsigned int clr)
+{
+ struct ad5360_state *st = iio_priv(indio_dev);
+ unsigned int ret;
+
+ mutex_lock(&indio_dev->mlock);
+
+ st->ctrl |= set;
+ st->ctrl &= ~clr;
+
+ ret = ad5360_write_unlocked(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,
+ AD5360_REG_SF_CTRL, st->ctrl, 0);
+
+ mutex_unlock(&indio_dev->mlock);
+
+ return ret;
+}
+
+static ssize_t ad5360_write_dac_powerdown(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ bool pwr_down;
+ int ret;
+
+ ret = strtobool(buf, &pwr_down);
+ if (ret)
+ return ret;
+
+ if (pwr_down)
+ ret = ad5360_update_ctrl(indio_dev, AD5360_SF_CTRL_PWR_DOWN, 0);
+ else
+ ret = ad5360_update_ctrl(indio_dev, 0, AD5360_SF_CTRL_PWR_DOWN);
+
+ return ret ? ret : len;
+}
+
+static IIO_DEVICE_ATTR(out_voltage_powerdown,
+ S_IRUGO | S_IWUSR,
+ ad5360_read_dac_powerdown,
+ ad5360_write_dac_powerdown, 0);
+
+static struct attribute *ad5360_attributes[] = {
+ &iio_dev_attr_out_voltage_powerdown.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ad5360_attribute_group = {
+ .attrs = ad5360_attributes,
+};
+
+static int ad5360_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad5360_state *st = iio_priv(indio_dev);
+ int max_val = (1 << chan->scan_type.realbits);
+ unsigned int ofs_index;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (val >= max_val || val < 0)
+ return -EINVAL;
+
+ return ad5360_write(indio_dev, AD5360_CMD_WRITE_DATA,
+ chan->address, val, chan->scan_type.shift);
+
+ case IIO_CHAN_INFO_CALIBBIAS:
+ if (val >= max_val || val < 0)
+ return -EINVAL;
+
+ return ad5360_write(indio_dev, AD5360_CMD_WRITE_OFFSET,
+ chan->address, val, chan->scan_type.shift);
+
+ case IIO_CHAN_INFO_CALIBSCALE:
+ if (val >= max_val || val < 0)
+ return -EINVAL;
+
+ return ad5360_write(indio_dev, AD5360_CMD_WRITE_GAIN,
+ chan->address, val, chan->scan_type.shift);
+
+ case IIO_CHAN_INFO_OFFSET:
+ if (val <= -max_val || val > 0)
+ return -EINVAL;
+
+ val = -val;
+
+ /* offset is supposed to have the same scale as raw, but it
+ * is always 14bits wide, so on a chip where the raw value has
+ * more bits, we need to shift offset. */
+ val >>= (chan->scan_type.realbits - 14);
+
+ /* There is one DAC offset register per vref. Changing one
+ * channels offset will also change the offset for all other
+ * channels which share the same vref supply. */
+ ofs_index = ad5360_get_channel_vref_index(st, chan->channel);
+ return ad5360_write(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,
+ AD5360_REG_SF_OFS(ofs_index), val, 0);
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static int ad5360_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long m)
+{
+ struct ad5360_state *st = iio_priv(indio_dev);
+ unsigned int ofs_index;
+ int scale_uv;
+ int ret;
+
+ switch (m) {
+ case IIO_CHAN_INFO_RAW:
+ ret = ad5360_read(indio_dev, AD5360_READBACK_X1A,
+ chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret >> chan->scan_type.shift;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ scale_uv = ad5360_get_channel_vref(st, chan->channel);
+ if (scale_uv < 0)
+ return scale_uv;
+
+ /* vout = 4 * vref * dac_code */
+ *val = scale_uv * 4 / 1000;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ ret = ad5360_read(indio_dev, AD5360_READBACK_OFFSET,
+ chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ ret = ad5360_read(indio_dev, AD5360_READBACK_GAIN,
+ chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_OFFSET:
+ ofs_index = ad5360_get_channel_vref_index(st, chan->channel);
+ ret = ad5360_read(indio_dev, AD5360_READBACK_SF,
+ AD5360_REG_SF_OFS(ofs_index));
+ if (ret < 0)
+ return ret;
+
+ ret <<= (chan->scan_type.realbits - 14);
+ *val = -ret;
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info ad5360_info = {
+ .read_raw = ad5360_read_raw,
+ .write_raw = ad5360_write_raw,
+ .attrs = &ad5360_attribute_group,
+ .driver_module = THIS_MODULE,
+};
+
+static const char * const ad5360_vref_name[] = {
+ "vref0", "vref1", "vref2"
+};
+
+static int ad5360_alloc_channels(struct iio_dev *indio_dev)
+{
+ struct ad5360_state *st = iio_priv(indio_dev);
+ struct iio_chan_spec *channels;
+ unsigned int i;
+
+ channels = kcalloc(st->chip_info->num_channels,
+ sizeof(struct iio_chan_spec), GFP_KERNEL);
+
+ if (!channels)
+ return -ENOMEM;
+
+ for (i = 0; i < st->chip_info->num_channels; ++i) {
+ channels[i] = st->chip_info->channel_template;
+ channels[i].channel = i;
+ channels[i].address = AD5360_CHAN_ADDR(i);
+ }
+
+ indio_dev->channels = channels;
+
+ return 0;
+}
+
+static int ad5360_probe(struct spi_device *spi)
+{
+ enum ad5360_type type = spi_get_device_id(spi)->driver_data;
+ struct iio_dev *indio_dev;
+ struct ad5360_state *st;
+ unsigned int i;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (indio_dev == NULL) {
+ dev_err(&spi->dev, "Failed to allocate iio device\n");
+ return -ENOMEM;
+ }
+
+ st = iio_priv(indio_dev);
+ spi_set_drvdata(spi, indio_dev);
+
+ st->chip_info = &ad5360_chip_info_tbl[type];
+ st->spi = spi;
+
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->info = &ad5360_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->num_channels = st->chip_info->num_channels;
+
+ ret = ad5360_alloc_channels(indio_dev);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to allocate channel spec: %d\n", ret);
+ return ret;
+ }
+
+ for (i = 0; i < st->chip_info->num_vrefs; ++i)
+ st->vref_reg[i].supply = ad5360_vref_name[i];
+
+ ret = devm_regulator_bulk_get(&st->spi->dev, st->chip_info->num_vrefs,
+ st->vref_reg);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to request vref regulators: %d\n", ret);
+ goto error_free_channels;
+ }
+
+ ret = regulator_bulk_enable(st->chip_info->num_vrefs, st->vref_reg);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to enable vref regulators: %d\n", ret);
+ goto error_free_channels;
+ }
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&spi->dev, "Failed to register iio device: %d\n", ret);
+ goto error_disable_reg;
+ }
+
+ return 0;
+
+error_disable_reg:
+ regulator_bulk_disable(st->chip_info->num_vrefs, st->vref_reg);
+error_free_channels:
+ kfree(indio_dev->channels);
+
+ return ret;
+}
+
+static int ad5360_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ad5360_state *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ kfree(indio_dev->channels);
+
+ regulator_bulk_disable(st->chip_info->num_vrefs, st->vref_reg);
+
+ return 0;
+}
+
+static const struct spi_device_id ad5360_ids[] = {
+ { "ad5360", ID_AD5360 },
+ { "ad5361", ID_AD5361 },
+ { "ad5362", ID_AD5362 },
+ { "ad5363", ID_AD5363 },
+ { "ad5370", ID_AD5370 },
+ { "ad5371", ID_AD5371 },
+ { "ad5372", ID_AD5372 },
+ { "ad5373", ID_AD5373 },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad5360_ids);
+
+static struct spi_driver ad5360_driver = {
+ .driver = {
+ .name = "ad5360",
+ .owner = THIS_MODULE,
+ },
+ .probe = ad5360_probe,
+ .remove = ad5360_remove,
+ .id_table = ad5360_ids,
+};
+module_spi_driver(ad5360_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices AD5360/61/62/63/70/71/72/73 DAC");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff