| /* |
| * 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/iio/iio.h> |
| #include <linux/iio/sysfs.h> |
| #include <linux/iio/events.h> |
| #include <linux/iio/dac/ad5504.h> |
| |
| #define AD5505_BITS 12 |
| #define AD5504_RES_MASK ((1 << (AD5505_BITS)) - 1) |
| |
| #define AD5504_CMD_READ (1 << 15) |
| #define AD5504_CMD_WRITE (0 << 15) |
| #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 |
| * @us: spi_device |
| * @reg: supply regulator |
| * @vref_mv: actual reference voltage used |
| * @pwr_down_mask power down mask |
| * @pwr_down_mode current power down mode |
| */ |
| |
| struct ad5504_state { |
| struct spi_device *spi; |
| struct regulator *reg; |
| unsigned short vref_mv; |
| unsigned pwr_down_mask; |
| unsigned pwr_down_mode; |
| }; |
| |
| /** |
| * ad5504_supported_device_ids: |
| */ |
| |
| enum ad5504_supported_device_ids { |
| ID_AD5504, |
| ID_AD5501, |
| }; |
| |
| static int ad5504_spi_write(struct spi_device *spi, u8 addr, u16 val) |
| { |
| u16 tmp = cpu_to_be16(AD5504_CMD_WRITE | |
| AD5504_ADDR(addr) | |
| (val & AD5504_RES_MASK)); |
| |
| return spi_write(spi, (u8 *)&tmp, 2); |
| } |
| |
| static int ad5504_spi_read(struct spi_device *spi, u8 addr) |
| { |
| u16 tmp = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr)); |
| u16 val; |
| int ret; |
| struct spi_transfer t = { |
| .tx_buf = &tmp, |
| .rx_buf = &val, |
| .len = 2, |
| }; |
| struct spi_message m; |
| |
| spi_message_init(&m); |
| spi_message_add_tail(&t, &m); |
| ret = spi_sync(spi, &m); |
| |
| if (ret < 0) |
| return ret; |
| |
| return be16_to_cpu(val) & 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); |
| unsigned long scale_uv; |
| int ret; |
| |
| switch (m) { |
| case IIO_CHAN_INFO_RAW: |
| ret = ad5504_spi_read(st->spi, chan->address); |
| if (ret < 0) |
| return ret; |
| |
| *val = ret; |
| |
| return IIO_VAL_INT; |
| 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 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); |
| int ret; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| if (val >= (1 << chan->scan_type.realbits) || val < 0) |
| return -EINVAL; |
| |
| return ad5504_spi_write(st->spi, chan->address, val); |
| default: |
| ret = -EINVAL; |
| } |
| |
| 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->spi, 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->spi, 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, |
| }, |
| IIO_ENUM("powerdown_mode", true, &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 = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \ |
| IIO_CHAN_INFO_SCALE_SHARED_BIT, \ |
| .address = AD5504_ADDR_DAC(_chan), \ |
| .scan_type = IIO_ST('u', 12, 16, 0), \ |
| .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 = iio_device_alloc(sizeof(*st)); |
| if (indio_dev == NULL) { |
| ret = -ENOMEM; |
| goto error_ret; |
| } |
| reg = regulator_get(&spi->dev, "vcc"); |
| if (!IS_ERR(reg)) { |
| ret = regulator_enable(reg); |
| if (ret) |
| goto error_put_reg; |
| |
| 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 = request_threaded_irq(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_free_irq; |
| |
| return 0; |
| |
| error_free_irq: |
| if (spi->irq) |
| free_irq(spi->irq, indio_dev); |
| error_disable_reg: |
| if (!IS_ERR(reg)) |
| regulator_disable(reg); |
| error_put_reg: |
| if (!IS_ERR(reg)) |
| regulator_put(reg); |
| |
| iio_device_free(indio_dev); |
| error_ret: |
| 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 (spi->irq) |
| free_irq(spi->irq, 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 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"); |