// SPDX-License-Identifier: GPL-2.0-only /* * AD5760, AD5780, AD5781, AD5790, AD5791 Voltage Output Digital to Analog * Converter * * Copyright 2011 Analog Devices Inc. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define AD5791_DAC_MASK GENMASK(19, 0) #define AD5791_CMD_READ BIT(23) #define AD5791_CMD_WRITE 0 #define AD5791_ADDR(addr) ((addr) << 20) /* Registers */ #define AD5791_ADDR_NOOP 0 #define AD5791_ADDR_DAC0 1 #define AD5791_ADDR_CTRL 2 #define AD5791_ADDR_CLRCODE 3 #define AD5791_ADDR_SW_CTRL 4 /* Control Register */ #define AD5791_CTRL_RBUF BIT(1) #define AD5791_CTRL_OPGND BIT(2) #define AD5791_CTRL_DACTRI BIT(3) #define AD5791_CTRL_BIN2SC BIT(4) #define AD5791_CTRL_SDODIS BIT(5) #define AD5761_CTRL_LINCOMP(x) ((x) << 6) #define AD5791_LINCOMP_0_10 0 #define AD5791_LINCOMP_10_12 1 #define AD5791_LINCOMP_12_16 2 #define AD5791_LINCOMP_16_19 3 #define AD5791_LINCOMP_19_20 12 #define AD5780_LINCOMP_0_10 0 #define AD5780_LINCOMP_10_20 12 /* Software Control Register */ #define AD5791_SWCTRL_LDAC BIT(0) #define AD5791_SWCTRL_CLR BIT(1) #define AD5791_SWCTRL_RESET BIT(2) #define AD5791_DAC_PWRDN_6K 0 #define AD5791_DAC_PWRDN_3STATE 1 /** * struct ad5791_chip_info - chip specific information * @name: name of the dac chip * @channel: channel specification * @get_lin_comp: function pointer to the device specific function */ struct ad5791_chip_info { const char *name; const struct iio_chan_spec channel; int (*get_lin_comp)(unsigned int span); }; /** * struct ad5791_state - driver instance specific data * @spi: spi_device * @reg_vdd: positive supply regulator * @reg_vss: negative supply regulator * @gpio_reset: reset gpio * @gpio_clear: clear gpio * @gpio_ldac: load dac gpio * @chip_info: chip model specific constants * @vref_mv: actual reference voltage used * @vref_neg_mv: voltage of the negative supply * @ctrl: control register cache * @pwr_down_mode: current power down mode * @pwr_down: true if device is powered down * @data: spi transfer buffers */ struct ad5791_state { struct spi_device *spi; struct regulator *reg_vdd; struct regulator *reg_vss; struct gpio_desc *gpio_reset; struct gpio_desc *gpio_clear; struct gpio_desc *gpio_ldac; const struct ad5791_chip_info *chip_info; unsigned short vref_mv; unsigned int vref_neg_mv; unsigned ctrl; unsigned pwr_down_mode; bool pwr_down; union { __be32 d32; u8 d8[4]; } data[3] __aligned(IIO_DMA_MINALIGN); }; static int ad5791_spi_write(struct ad5791_state *st, u8 addr, u32 val) { st->data[0].d32 = cpu_to_be32(AD5791_CMD_WRITE | AD5791_ADDR(addr) | (val & AD5791_DAC_MASK)); return spi_write(st->spi, &st->data[0].d8[1], 3); } static int ad5791_spi_read(struct ad5791_state *st, u8 addr, u32 *val) { int ret; struct spi_transfer xfers[] = { { .tx_buf = &st->data[0].d8[1], .bits_per_word = 8, .len = 3, .cs_change = 1, }, { .tx_buf = &st->data[1].d8[1], .rx_buf = &st->data[2].d8[1], .bits_per_word = 8, .len = 3, }, }; st->data[0].d32 = cpu_to_be32(AD5791_CMD_READ | AD5791_ADDR(addr)); st->data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP)); ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers)); *val = be32_to_cpu(st->data[2].d32); return ret; } static const char * const ad5791_powerdown_modes[] = { "6kohm_to_gnd", "three_state", }; static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev, const struct iio_chan_spec *chan) { struct ad5791_state *st = iio_priv(indio_dev); return st->pwr_down_mode; } static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, unsigned int mode) { struct ad5791_state *st = iio_priv(indio_dev); st->pwr_down_mode = mode; return 0; } static const struct iio_enum ad5791_powerdown_mode_enum = { .items = ad5791_powerdown_modes, .num_items = ARRAY_SIZE(ad5791_powerdown_modes), .get = ad5791_get_powerdown_mode, .set = ad5791_set_powerdown_mode, }; static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev, uintptr_t private, const struct iio_chan_spec *chan, char *buf) { struct ad5791_state *st = iio_priv(indio_dev); return sysfs_emit(buf, "%d\n", st->pwr_down); } static ssize_t ad5791_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 ad5791_state *st = iio_priv(indio_dev); ret = kstrtobool(buf, &pwr_down); if (ret) return ret; if (!pwr_down) { st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI); } else { if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K) st->ctrl |= AD5791_CTRL_OPGND; else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE) st->ctrl |= AD5791_CTRL_DACTRI; } st->pwr_down = pwr_down; ret = ad5791_spi_write(st, AD5791_ADDR_CTRL, st->ctrl); return ret ? ret : len; } static int ad5791_get_lin_comp(unsigned int span) { if (span <= 10000) return AD5791_LINCOMP_0_10; else if (span <= 12000) return AD5791_LINCOMP_10_12; else if (span <= 16000) return AD5791_LINCOMP_12_16; else if (span <= 19000) return AD5791_LINCOMP_16_19; else return AD5791_LINCOMP_19_20; } static int ad5780_get_lin_comp(unsigned int span) { if (span <= 10000) return AD5780_LINCOMP_0_10; else return AD5780_LINCOMP_10_20; } static int ad5791_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long m) { struct ad5791_state *st = iio_priv(indio_dev); u64 val64; int ret; switch (m) { case IIO_CHAN_INFO_RAW: ret = ad5791_spi_read(st, chan->address, val); if (ret) return ret; *val &= AD5791_DAC_MASK; *val >>= chan->scan_type.shift; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: *val = st->vref_mv; *val2 = (1 << chan->scan_type.realbits) - 1; return IIO_VAL_FRACTIONAL; case IIO_CHAN_INFO_OFFSET: val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits); do_div(val64, st->vref_mv); *val = -val64; return IIO_VAL_INT; default: return -EINVAL; } }; static const struct iio_chan_spec_ext_info ad5791_ext_info[] = { { .name = "powerdown", .shared = IIO_SHARED_BY_TYPE, .read = ad5791_read_dac_powerdown, .write = ad5791_write_dac_powerdown, }, IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5791_powerdown_mode_enum), IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5791_powerdown_mode_enum), { }, }; #define AD5791_DEFINE_CHIP_INFO(_name, bits, _shift, _lin_comp) \ static const struct ad5791_chip_info _name##_chip_info = { \ .name = #_name, \ .get_lin_comp = &(_lin_comp), \ .channel = { \ .type = IIO_VOLTAGE, \ .output = 1, \ .indexed = 1, \ .address = AD5791_ADDR_DAC0, \ .channel = 0, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ BIT(IIO_CHAN_INFO_OFFSET), \ .scan_type = { \ .sign = 'u', \ .realbits = (bits), \ .storagebits = 24, \ .shift = (_shift), \ }, \ .ext_info = ad5791_ext_info, \ }, \ } AD5791_DEFINE_CHIP_INFO(ad5760, 16, 4, ad5780_get_lin_comp); AD5791_DEFINE_CHIP_INFO(ad5780, 18, 2, ad5780_get_lin_comp); AD5791_DEFINE_CHIP_INFO(ad5781, 18, 2, ad5791_get_lin_comp); AD5791_DEFINE_CHIP_INFO(ad5790, 20, 0, ad5791_get_lin_comp); AD5791_DEFINE_CHIP_INFO(ad5791, 20, 0, ad5791_get_lin_comp); static int ad5791_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) { struct ad5791_state *st = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_RAW: val &= GENMASK(chan->scan_type.realbits - 1, 0); val <<= chan->scan_type.shift; return ad5791_spi_write(st, chan->address, val); default: return -EINVAL; } } static const struct iio_info ad5791_info = { .read_raw = &ad5791_read_raw, .write_raw = &ad5791_write_raw, }; static int ad5791_probe(struct spi_device *spi) { const struct ad5791_platform_data *pdata = dev_get_platdata(&spi->dev); struct iio_dev *indio_dev; struct ad5791_state *st; int ret, pos_voltage_uv = 0, neg_voltage_uv = 0; bool use_rbuf_gain2; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); if (!indio_dev) return -ENOMEM; st = iio_priv(indio_dev); st->gpio_reset = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(st->gpio_reset)) return PTR_ERR(st->gpio_reset); st->gpio_clear = devm_gpiod_get_optional(&spi->dev, "clear", GPIOD_OUT_LOW); if (IS_ERR(st->gpio_clear)) return PTR_ERR(st->gpio_clear); st->gpio_ldac = devm_gpiod_get_optional(&spi->dev, "ldac", GPIOD_OUT_HIGH); if (IS_ERR(st->gpio_ldac)) return PTR_ERR(st->gpio_ldac); st->pwr_down = true; st->spi = spi; if (pdata) use_rbuf_gain2 = pdata->use_rbuf_gain2; else use_rbuf_gain2 = device_property_read_bool(&spi->dev, "adi,rbuf-gain2-en"); pos_voltage_uv = devm_regulator_get_enable_read_voltage(&spi->dev, "vdd"); if (pos_voltage_uv < 0 && pos_voltage_uv != -ENODEV) return dev_err_probe(&spi->dev, pos_voltage_uv, "failed to get vdd voltage\n"); neg_voltage_uv = devm_regulator_get_enable_read_voltage(&spi->dev, "vss"); if (neg_voltage_uv < 0 && neg_voltage_uv != -ENODEV) return dev_err_probe(&spi->dev, neg_voltage_uv, "failed to get vss voltage\n"); if (neg_voltage_uv >= 0 && pos_voltage_uv >= 0) { st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000; st->vref_neg_mv = neg_voltage_uv / 1000; } else if (pdata) { st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv; st->vref_neg_mv = pdata->vref_neg_mv; } else { dev_warn(&spi->dev, "reference voltage unspecified\n"); } if (st->gpio_reset) { fsleep(20); gpiod_set_value_cansleep(st->gpio_reset, 0); } else { ret = ad5791_spi_write(st, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET); if (ret) return dev_err_probe(&spi->dev, ret, "fail to reset\n"); } st->chip_info = spi_get_device_match_data(spi); if (!st->chip_info) return dev_err_probe(&spi->dev, -EINVAL, "no chip info\n"); st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv)) | (use_rbuf_gain2 ? 0 : AD5791_CTRL_RBUF) | AD5791_CTRL_BIN2SC; ret = ad5791_spi_write(st, AD5791_ADDR_CTRL, st->ctrl | AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI); if (ret) return dev_err_probe(&spi->dev, ret, "fail to write ctrl register\n"); indio_dev->info = &ad5791_info; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->channels = &st->chip_info->channel; indio_dev->num_channels = 1; indio_dev->name = st->chip_info->name; return devm_iio_device_register(&spi->dev, indio_dev); } static const struct of_device_id ad5791_of_match[] = { { .compatible = "adi,ad5760", .data = &ad5760_chip_info }, { .compatible = "adi,ad5780", .data = &ad5780_chip_info }, { .compatible = "adi,ad5781", .data = &ad5781_chip_info }, { .compatible = "adi,ad5790", .data = &ad5790_chip_info }, { .compatible = "adi,ad5791", .data = &ad5791_chip_info }, { } }; MODULE_DEVICE_TABLE(of, ad5791_of_match); static const struct spi_device_id ad5791_id[] = { { "ad5760", (kernel_ulong_t)&ad5760_chip_info }, { "ad5780", (kernel_ulong_t)&ad5780_chip_info }, { "ad5781", (kernel_ulong_t)&ad5781_chip_info }, { "ad5790", (kernel_ulong_t)&ad5790_chip_info }, { "ad5791", (kernel_ulong_t)&ad5791_chip_info }, { } }; MODULE_DEVICE_TABLE(spi, ad5791_id); static struct spi_driver ad5791_driver = { .driver = { .name = "ad5791", .of_match_table = ad5791_of_match, }, .probe = ad5791_probe, .id_table = ad5791_id, }; module_spi_driver(ad5791_driver); MODULE_AUTHOR("Michael Hennerich "); MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC"); MODULE_LICENSE("GPL v2");