| /* |
| * AD5686R, AD5685R, AD5684R Digital to analog converters driver |
| * |
| * Copyright 2011 Analog Devices Inc. |
| * |
| * Licensed under the GPL-2. |
| */ |
| |
| #include <linux/interrupt.h> |
| #include <linux/fs.h> |
| #include <linux/device.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/module.h> |
| |
| #include "../iio.h" |
| #include "../sysfs.h" |
| #include "dac.h" |
| |
| #define AD5686_DAC_CHANNELS 4 |
| |
| #define AD5686_ADDR(x) ((x) << 16) |
| #define AD5686_CMD(x) ((x) << 20) |
| |
| #define AD5686_ADDR_DAC(chan) (0x1 << (chan)) |
| #define AD5686_ADDR_ALL_DAC 0xF |
| |
| #define AD5686_CMD_NOOP 0x0 |
| #define AD5686_CMD_WRITE_INPUT_N 0x1 |
| #define AD5686_CMD_UPDATE_DAC_N 0x2 |
| #define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3 |
| #define AD5686_CMD_POWERDOWN_DAC 0x4 |
| #define AD5686_CMD_LDAC_MASK 0x5 |
| #define AD5686_CMD_RESET 0x6 |
| #define AD5686_CMD_INTERNAL_REFER_SETUP 0x7 |
| #define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8 |
| #define AD5686_CMD_READBACK_ENABLE 0x9 |
| |
| #define AD5686_LDAC_PWRDN_NONE 0x0 |
| #define AD5686_LDAC_PWRDN_1K 0x1 |
| #define AD5686_LDAC_PWRDN_100K 0x2 |
| #define AD5686_LDAC_PWRDN_3STATE 0x3 |
| |
| /** |
| * struct ad5686_chip_info - chip specific information |
| * @int_vref_mv: AD5620/40/60: the internal reference voltage |
| * @channel: channel specification |
| */ |
| |
| struct ad5686_chip_info { |
| u16 int_vref_mv; |
| struct iio_chan_spec channel[AD5686_DAC_CHANNELS]; |
| }; |
| |
| /** |
| * struct ad5446_state - driver instance specific data |
| * @spi: spi_device |
| * @chip_info: chip model specific constants, available modes etc |
| * @reg: supply regulator |
| * @vref_mv: actual reference voltage used |
| * @pwr_down_mask: power down mask |
| * @pwr_down_mode: current power down mode |
| * @data: spi transfer buffers |
| */ |
| |
| struct ad5686_state { |
| struct spi_device *spi; |
| const struct ad5686_chip_info *chip_info; |
| struct regulator *reg; |
| unsigned short vref_mv; |
| unsigned pwr_down_mask; |
| unsigned pwr_down_mode; |
| /* |
| * DMA (thus cache coherency maintenance) requires the |
| * transfer buffers to live in their own cache lines. |
| */ |
| |
| union { |
| u32 d32; |
| u8 d8[4]; |
| } data[3] ____cacheline_aligned; |
| }; |
| |
| /** |
| * ad5686_supported_device_ids: |
| */ |
| |
| enum ad5686_supported_device_ids { |
| ID_AD5684, |
| ID_AD5685, |
| ID_AD5686, |
| }; |
| #define AD5868_CHANNEL(chan, bits, shift) { \ |
| .type = IIO_VOLTAGE, \ |
| .indexed = 1, \ |
| .output = 1, \ |
| .channel = chan, \ |
| .info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED), \ |
| .address = AD5686_ADDR_DAC(chan), \ |
| .scan_type = IIO_ST('u', bits, 16, shift) \ |
| } |
| static const struct ad5686_chip_info ad5686_chip_info_tbl[] = { |
| [ID_AD5684] = { |
| .channel[0] = AD5868_CHANNEL(0, 12, 4), |
| .channel[1] = AD5868_CHANNEL(1, 12, 4), |
| .channel[2] = AD5868_CHANNEL(2, 12, 4), |
| .channel[3] = AD5868_CHANNEL(3, 12, 4), |
| .int_vref_mv = 2500, |
| }, |
| [ID_AD5685] = { |
| .channel[0] = AD5868_CHANNEL(0, 14, 2), |
| .channel[1] = AD5868_CHANNEL(1, 14, 2), |
| .channel[2] = AD5868_CHANNEL(2, 14, 2), |
| .channel[3] = AD5868_CHANNEL(3, 14, 2), |
| .int_vref_mv = 2500, |
| }, |
| [ID_AD5686] = { |
| .channel[0] = AD5868_CHANNEL(0, 16, 0), |
| .channel[1] = AD5868_CHANNEL(1, 16, 0), |
| .channel[2] = AD5868_CHANNEL(2, 16, 0), |
| .channel[3] = AD5868_CHANNEL(3, 16, 0), |
| .int_vref_mv = 2500, |
| }, |
| }; |
| |
| static int ad5686_spi_write(struct ad5686_state *st, |
| u8 cmd, u8 addr, u16 val, u8 shift) |
| { |
| val <<= shift; |
| |
| st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) | |
| AD5686_ADDR(addr) | |
| val); |
| |
| return spi_write(st->spi, &st->data[0].d8[1], 3); |
| } |
| |
| static int ad5686_spi_read(struct ad5686_state *st, u8 addr) |
| { |
| struct spi_transfer t[] = { |
| { |
| .tx_buf = &st->data[0].d8[1], |
| .len = 3, |
| .cs_change = 1, |
| }, { |
| .tx_buf = &st->data[1].d8[1], |
| .rx_buf = &st->data[2].d8[1], |
| .len = 3, |
| }, |
| }; |
| struct spi_message m; |
| int ret; |
| |
| spi_message_init(&m); |
| spi_message_add_tail(&t[0], &m); |
| spi_message_add_tail(&t[1], &m); |
| |
| st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) | |
| AD5686_ADDR(addr)); |
| st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP)); |
| |
| ret = spi_sync(st->spi, &m); |
| if (ret < 0) |
| return ret; |
| |
| return be32_to_cpu(st->data[2].d32); |
| } |
| |
| static ssize_t ad5686_read_powerdown_mode(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct ad5686_state *st = iio_priv(indio_dev); |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| |
| char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"}; |
| |
| return sprintf(buf, "%s\n", mode[(st->pwr_down_mode >> |
| (this_attr->address * 2)) & 0x3]); |
| } |
| |
| static ssize_t ad5686_write_powerdown_mode(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t len) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct ad5686_state *st = iio_priv(indio_dev); |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| unsigned mode; |
| |
| if (sysfs_streq(buf, "1kohm_to_gnd")) |
| mode = AD5686_LDAC_PWRDN_1K; |
| else if (sysfs_streq(buf, "100kohm_to_gnd")) |
| mode = AD5686_LDAC_PWRDN_100K; |
| else if (sysfs_streq(buf, "three_state")) |
| mode = AD5686_LDAC_PWRDN_3STATE; |
| else |
| return -EINVAL; |
| |
| st->pwr_down_mode &= ~(0x3 << (this_attr->address * 2)); |
| st->pwr_down_mode |= (mode << (this_attr->address * 2)); |
| |
| return len; |
| } |
| |
| static ssize_t ad5686_read_dac_powerdown(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct ad5686_state *st = iio_priv(indio_dev); |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| |
| return sprintf(buf, "%d\n", !!(st->pwr_down_mask & |
| (0x3 << (this_attr->address * 2)))); |
| } |
| |
| static ssize_t ad5686_write_dac_powerdown(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t len) |
| { |
| bool readin; |
| int ret; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct ad5686_state *st = iio_priv(indio_dev); |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| |
| ret = strtobool(buf, &readin); |
| if (ret) |
| return ret; |
| |
| if (readin == true) |
| st->pwr_down_mask |= (0x3 << (this_attr->address * 2)); |
| else |
| st->pwr_down_mask &= ~(0x3 << (this_attr->address * 2)); |
| |
| ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0, |
| st->pwr_down_mask & st->pwr_down_mode, 0); |
| |
| return ret ? ret : len; |
| } |
| |
| static IIO_CONST_ATTR(out_voltage_powerdown_mode_available, |
| "1kohm_to_gnd 100kohm_to_gnd three_state"); |
| |
| #define IIO_DEV_ATTR_DAC_POWERDOWN_MODE(_num) \ |
| IIO_DEVICE_ATTR(out_voltage##_num##_powerdown_mode, \ |
| S_IRUGO | S_IWUSR, \ |
| ad5686_read_powerdown_mode, \ |
| ad5686_write_powerdown_mode, _num) |
| |
| static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(0); |
| static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(1); |
| static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(2); |
| static IIO_DEV_ATTR_DAC_POWERDOWN_MODE(3); |
| |
| #define IIO_DEV_ATTR_DAC_POWERDOWN(_num) \ |
| IIO_DEVICE_ATTR(out_voltage##_num##_powerdown, \ |
| S_IRUGO | S_IWUSR, \ |
| ad5686_read_dac_powerdown, \ |
| ad5686_write_dac_powerdown, _num) |
| |
| static IIO_DEV_ATTR_DAC_POWERDOWN(0); |
| static IIO_DEV_ATTR_DAC_POWERDOWN(1); |
| static IIO_DEV_ATTR_DAC_POWERDOWN(2); |
| static IIO_DEV_ATTR_DAC_POWERDOWN(3); |
| |
| static struct attribute *ad5686_attributes[] = { |
| &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr, |
| &iio_dev_attr_out_voltage1_powerdown.dev_attr.attr, |
| &iio_dev_attr_out_voltage2_powerdown.dev_attr.attr, |
| &iio_dev_attr_out_voltage3_powerdown.dev_attr.attr, |
| &iio_dev_attr_out_voltage0_powerdown_mode.dev_attr.attr, |
| &iio_dev_attr_out_voltage1_powerdown_mode.dev_attr.attr, |
| &iio_dev_attr_out_voltage2_powerdown_mode.dev_attr.attr, |
| &iio_dev_attr_out_voltage3_powerdown_mode.dev_attr.attr, |
| &iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr, |
| NULL, |
| }; |
| |
| static const struct attribute_group ad5686_attribute_group = { |
| .attrs = ad5686_attributes, |
| }; |
| |
| static int ad5686_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, |
| int *val2, |
| long m) |
| { |
| struct ad5686_state *st = iio_priv(indio_dev); |
| unsigned long scale_uv; |
| int ret; |
| |
| switch (m) { |
| case 0: |
| mutex_lock(&indio_dev->mlock); |
| ret = ad5686_spi_read(st, chan->address); |
| mutex_unlock(&indio_dev->mlock); |
| if (ret < 0) |
| return ret; |
| *val = ret; |
| return IIO_VAL_INT; |
| break; |
| case (1 << IIO_CHAN_INFO_SCALE_SHARED): |
| scale_uv = (st->vref_mv * 100000) |
| >> (chan->scan_type.realbits); |
| *val = scale_uv / 100000; |
| *val2 = (scale_uv % 100000) * 10; |
| return IIO_VAL_INT_PLUS_MICRO; |
| |
| } |
| return -EINVAL; |
| } |
| |
| static int ad5686_write_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int val, |
| int val2, |
| long mask) |
| { |
| struct ad5686_state *st = iio_priv(indio_dev); |
| int ret; |
| |
| switch (mask) { |
| case 0: |
| if (val > (1 << chan->scan_type.realbits) || val < 0) |
| return -EINVAL; |
| |
| mutex_lock(&indio_dev->mlock); |
| ret = ad5686_spi_write(st, |
| AD5686_CMD_WRITE_INPUT_N_UPDATE_N, |
| chan->address, |
| val, |
| chan->scan_type.shift); |
| mutex_unlock(&indio_dev->mlock); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| |
| return ret; |
| } |
| |
| static const struct iio_info ad5686_info = { |
| .read_raw = ad5686_read_raw, |
| .write_raw = ad5686_write_raw, |
| .attrs = &ad5686_attribute_group, |
| .driver_module = THIS_MODULE, |
| }; |
| |
| static int __devinit ad5686_probe(struct spi_device *spi) |
| { |
| struct ad5686_state *st; |
| struct iio_dev *indio_dev; |
| int ret, regdone = 0, voltage_uv = 0; |
| |
| indio_dev = iio_allocate_device(sizeof(*st)); |
| if (indio_dev == NULL) |
| return -ENOMEM; |
| |
| st = iio_priv(indio_dev); |
| spi_set_drvdata(spi, 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); |
| } |
| |
| st->chip_info = |
| &ad5686_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->spi = spi; |
| |
| indio_dev->dev.parent = &spi->dev; |
| indio_dev->name = spi_get_device_id(spi)->name; |
| indio_dev->info = &ad5686_info; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| indio_dev->channels = st->chip_info->channel; |
| indio_dev->num_channels = AD5686_DAC_CHANNELS; |
| |
| regdone = 1; |
| ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0, |
| !!voltage_uv, 0); |
| 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_free_device(indio_dev); |
| |
| return ret; |
| } |
| |
| static int __devexit ad5686_remove(struct spi_device *spi) |
| { |
| struct iio_dev *indio_dev = spi_get_drvdata(spi); |
| struct ad5686_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_free_device(indio_dev); |
| |
| return 0; |
| } |
| |
| static const struct spi_device_id ad5686_id[] = { |
| {"ad5684", ID_AD5684}, |
| {"ad5685", ID_AD5685}, |
| {"ad5686", ID_AD5686}, |
| {} |
| }; |
| |
| static struct spi_driver ad5686_driver = { |
| .driver = { |
| .name = "ad5686", |
| .owner = THIS_MODULE, |
| }, |
| .probe = ad5686_probe, |
| .remove = __devexit_p(ad5686_remove), |
| .id_table = ad5686_id, |
| }; |
| |
| static __init int ad5686_spi_init(void) |
| { |
| return spi_register_driver(&ad5686_driver); |
| } |
| module_init(ad5686_spi_init); |
| |
| static __exit void ad5686_spi_exit(void) |
| { |
| spi_unregister_driver(&ad5686_driver); |
| } |
| module_exit(ad5686_spi_exit); |
| |
| MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); |
| MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC"); |
| MODULE_LICENSE("GPL v2"); |