1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/iio/dac/ad5624r_spi.c b/drivers/iio/dac/ad5624r_spi.c
new file mode 100644
index 000000000000..6a7d6a48cc6d
--- /dev/null
+++ b/drivers/iio/dac/ad5624r_spi.c
@@ -0,0 +1,324 @@
+/*
+ * AD5624R, AD5644R, AD5664R Digital to analog convertors spi driver
+ *
+ * Copyright 2010-2011 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/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#include "ad5624r.h"
+
+static int ad5624r_spi_write(struct spi_device *spi,
+			     u8 cmd, u8 addr, u16 val, u8 len)
+{
+	u32 data;
+	u8 msg[3];
+
+	/*
+	 * The input shift register is 24 bits wide. The first two bits are
+	 * don't care bits. The next three are the command bits, C2 to C0,
+	 * followed by the 3-bit DAC address, A2 to A0, and then the
+	 * 16-, 14-, 12-bit data-word. The data-word comprises the 16-,
+	 * 14-, 12-bit input code followed by 0, 2, or 4 don't care bits,
+	 * for the AD5664R, AD5644R, and AD5624R, respectively.
+	 */
+	data = (0 << 22) | (cmd << 19) | (addr << 16) | (val << (16 - len));
+	msg[0] = data >> 16;
+	msg[1] = data >> 8;
+	msg[2] = data;
+
+	return spi_write(spi, msg, 3);
+}
+
+static int ad5624r_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val,
+			   int *val2,
+			   long m)
+{
+	struct ad5624r_state *st = iio_priv(indio_dev);
+	unsigned long scale_uv;
+
+	switch (m) {
+	case IIO_CHAN_INFO_SCALE:
+		scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
+		*val =  scale_uv / 1000;
+		*val2 = (scale_uv % 1000) * 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	}
+	return -EINVAL;
+}
+
+static int ad5624r_write_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan,
+			       int val,
+			       int val2,
+			       long mask)
+{
+	struct ad5624r_state *st = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (val >= (1 << chan->scan_type.realbits) || val < 0)
+			return -EINVAL;
+
+		return ad5624r_spi_write(st->us,
+				AD5624R_CMD_WRITE_INPUT_N_UPDATE_N,
+				chan->address, val,
+				chan->scan_type.shift);
+	default:
+		ret = -EINVAL;
+	}
+
+	return -EINVAL;
+}
+
+static const char * const ad5624r_powerdown_modes[] = {
+	"1kohm_to_gnd",
+	"100kohm_to_gnd",
+	"three_state"
+};
+
+static int ad5624r_get_powerdown_mode(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan)
+{
+	struct ad5624r_state *st = iio_priv(indio_dev);
+
+	return st->pwr_down_mode;
+}
+
+static int ad5624r_set_powerdown_mode(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, unsigned int mode)
+{
+	struct ad5624r_state *st = iio_priv(indio_dev);
+
+	st->pwr_down_mode = mode;
+
+	return 0;
+}
+
+static const struct iio_enum ad5624r_powerdown_mode_enum = {
+	.items = ad5624r_powerdown_modes,
+	.num_items = ARRAY_SIZE(ad5624r_powerdown_modes),
+	.get = ad5624r_get_powerdown_mode,
+	.set = ad5624r_set_powerdown_mode,
+};
+
+static ssize_t ad5624r_read_dac_powerdown(struct iio_dev *indio_dev,
+	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
+{
+	struct ad5624r_state *st = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n",
+			!!(st->pwr_down_mask & (1 << chan->channel)));
+}
+
+static ssize_t ad5624r_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 ad5624r_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 = ad5624r_spi_write(st->us, AD5624R_CMD_POWERDOWN_DAC, 0,
+				(st->pwr_down_mode << 4) |
+				st->pwr_down_mask, 16);
+
+	return ret ? ret : len;
+}
+
+static const struct iio_info ad5624r_info = {
+	.write_raw = ad5624r_write_raw,
+	.read_raw = ad5624r_read_raw,
+	.driver_module = THIS_MODULE,
+};
+
+static const struct iio_chan_spec_ext_info ad5624r_ext_info[] = {
+	{
+		.name = "powerdown",
+		.read = ad5624r_read_dac_powerdown,
+		.write = ad5624r_write_dac_powerdown,
+	},
+	IIO_ENUM("powerdown_mode", true, &ad5624r_powerdown_mode_enum),
+	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5624r_powerdown_mode_enum),
+	{ },
+};
+
+#define AD5624R_CHANNEL(_chan, _bits) { \
+	.type = IIO_VOLTAGE, \
+	.indexed = 1, \
+	.output = 1, \
+	.channel = (_chan), \
+	.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
+		     IIO_CHAN_INFO_SCALE_SHARED_BIT, \
+	.address = (_chan), \
+	.scan_type = IIO_ST('u', (_bits), 16, 16 - (_bits)), \
+	.ext_info = ad5624r_ext_info, \
+}
+
+#define DECLARE_AD5624R_CHANNELS(_name, _bits) \
+	const struct iio_chan_spec _name##_channels[] = { \
+		AD5624R_CHANNEL(0, _bits), \
+		AD5624R_CHANNEL(1, _bits), \
+		AD5624R_CHANNEL(2, _bits), \
+		AD5624R_CHANNEL(3, _bits), \
+}
+
+static DECLARE_AD5624R_CHANNELS(ad5624r, 12);
+static DECLARE_AD5624R_CHANNELS(ad5644r, 14);
+static DECLARE_AD5624R_CHANNELS(ad5664r, 16);
+
+static const struct ad5624r_chip_info ad5624r_chip_info_tbl[] = {
+	[ID_AD5624R3] = {
+		.channels = ad5624r_channels,
+		.int_vref_mv = 1250,
+	},
+	[ID_AD5624R5] = {
+		.channels = ad5624r_channels,
+		.int_vref_mv = 2500,
+	},
+	[ID_AD5644R3] = {
+		.channels = ad5644r_channels,
+		.int_vref_mv = 1250,
+	},
+	[ID_AD5644R5] = {
+		.channels = ad5644r_channels,
+		.int_vref_mv = 2500,
+	},
+	[ID_AD5664R3] = {
+		.channels = ad5664r_channels,
+		.int_vref_mv = 1250,
+	},
+	[ID_AD5664R5] = {
+		.channels = ad5664r_channels,
+		.int_vref_mv = 2500,
+	},
+};
+
+static int __devinit ad5624r_probe(struct spi_device *spi)
+{
+	struct ad5624r_state *st;
+	struct iio_dev *indio_dev;
+	int ret, voltage_uv = 0;
+
+	indio_dev = iio_device_alloc(sizeof(*st));
+	if (indio_dev == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	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;
+
+		voltage_uv = regulator_get_voltage(st->reg);
+	}
+
+	spi_set_drvdata(spi, indio_dev);
+	st->chip_info =
+		&ad5624r_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+
+	if (voltage_uv)
+		st->vref_mv = voltage_uv / 1000;
+	else
+		st->vref_mv = st->chip_info->int_vref_mv;
+
+	st->us = spi;
+
+	indio_dev->dev.parent = &spi->dev;
+	indio_dev->name = spi_get_device_id(spi)->name;
+	indio_dev->info = &ad5624r_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = st->chip_info->channels;
+	indio_dev->num_channels = AD5624R_DAC_CHANNELS;
+
+	ret = ad5624r_spi_write(spi, AD5624R_CMD_INTERNAL_REFER_SETUP, 0,
+				!!voltage_uv, 16);
+	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(st->reg))
+		regulator_disable(st->reg);
+error_put_reg:
+	if (!IS_ERR(st->reg))
+		regulator_put(st->reg);
+	iio_device_free(indio_dev);
+error_ret:
+
+	return ret;
+}
+
+static int __devexit ad5624r_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ad5624r_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	if (!IS_ERR(st->reg)) {
+		regulator_disable(st->reg);
+		regulator_put(st->reg);
+	}
+	iio_device_free(indio_dev);
+
+	return 0;
+}
+
+static const struct spi_device_id ad5624r_id[] = {
+	{"ad5624r3", ID_AD5624R3},
+	{"ad5644r3", ID_AD5644R3},
+	{"ad5664r3", ID_AD5664R3},
+	{"ad5624r5", ID_AD5624R5},
+	{"ad5644r5", ID_AD5644R5},
+	{"ad5664r5", ID_AD5664R5},
+	{}
+};
+MODULE_DEVICE_TABLE(spi, ad5624r_id);
+
+static struct spi_driver ad5624r_driver = {
+	.driver = {
+		   .name = "ad5624r",
+		   .owner = THIS_MODULE,
+		   },
+	.probe = ad5624r_probe,
+	.remove = __devexit_p(ad5624r_remove),
+	.id_table = ad5624r_id,
+};
+module_spi_driver(ad5624r_driver);
+
+MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
+MODULE_DESCRIPTION("Analog Devices AD5624/44/64R DAC spi driver");
+MODULE_LICENSE("GPL v2");