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");