From fd9373e41b9ba5b609f97e98a04687f4ff136aff Mon Sep 17 00:00:00 2001 From: Cristian Pop Date: Fri, 15 Jan 2021 13:21:05 +0200 Subject: iio: dac: ad5766: add driver support for AD5766 The AD5766/AD5767 are 16-channel, 16-bit/12-bit, voltage output dense DACs Digital-to-Analog converters. This change adds support for these DACs. Signed-off-by: Cristian Pop Link: https://lore.kernel.org/r/20210115112105.58652-3-cristian.pop@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/dac/Kconfig | 10 + drivers/iio/dac/Makefile | 1 + drivers/iio/dac/ad5766.c | 643 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 654 insertions(+) create mode 100644 drivers/iio/dac/ad5766.c (limited to 'drivers/iio') diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig index 6f6074a5d3db..cea07b4cced1 100644 --- a/drivers/iio/dac/Kconfig +++ b/drivers/iio/dac/Kconfig @@ -189,6 +189,16 @@ config AD5764 To compile this driver as a module, choose M here: the module will be called ad5764. +config AD5766 + tristate "Analog Devices AD5766/AD5767 DAC driver" + depends on SPI_MASTER + help + Say yes here to build support for Analog Devices AD5766, AD5767 + Digital to Analog Converter. + + To compile this driver as a module, choose M here: the + module will be called ad5766. + config AD5770R tristate "Analog Devices AD5770R IDAC driver" depends on SPI_MASTER diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile index 2fc481167724..33e16f14902a 100644 --- a/drivers/iio/dac/Makefile +++ b/drivers/iio/dac/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_AD5755) += ad5755.o obj-$(CONFIG_AD5755) += ad5758.o obj-$(CONFIG_AD5761) += ad5761.o obj-$(CONFIG_AD5764) += ad5764.o +obj-$(CONFIG_AD5766) += ad5766.o obj-$(CONFIG_AD5770R) += ad5770r.o obj-$(CONFIG_AD5791) += ad5791.o obj-$(CONFIG_AD5686) += ad5686.o diff --git a/drivers/iio/dac/ad5766.c b/drivers/iio/dac/ad5766.c new file mode 100644 index 000000000000..ef1618ea6a20 --- /dev/null +++ b/drivers/iio/dac/ad5766.c @@ -0,0 +1,643 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD5766, AD5767 + * Digital to Analog Converters driver + * Copyright 2019-2020 Analog Devices Inc. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#define AD5766_UPPER_WORD_SPI_MASK GENMASK(31, 16) +#define AD5766_LOWER_WORD_SPI_MASK GENMASK(15, 0) +#define AD5766_DITHER_SOURCE_MASK(ch) GENMASK(((2 * ch) + 1), (2 * ch)) +#define AD5766_DITHER_SOURCE(ch, source) BIT((ch * 2) + source) +#define AD5766_DITHER_SCALE_MASK(x) AD5766_DITHER_SOURCE_MASK(x) +#define AD5766_DITHER_SCALE(ch, scale) (scale << (ch * 2)) +#define AD5766_DITHER_ENABLE_MASK(ch) BIT(ch) +#define AD5766_DITHER_ENABLE(ch, state) ((!state) << ch) +#define AD5766_DITHER_INVERT_MASK(ch) BIT(ch) +#define AD5766_DITHER_INVERT(ch, state) (state << ch) + +#define AD5766_CMD_NOP_MUX_OUT 0x00 +#define AD5766_CMD_SDO_CNTRL 0x01 +#define AD5766_CMD_WR_IN_REG(x) (0x10 | ((x) & GENMASK(3, 0))) +#define AD5766_CMD_WR_DAC_REG(x) (0x20 | ((x) & GENMASK(3, 0))) +#define AD5766_CMD_SW_LDAC 0x30 +#define AD5766_CMD_SPAN_REG 0x40 +#define AD5766_CMD_WR_PWR_DITHER 0x51 +#define AD5766_CMD_WR_DAC_REG_ALL 0x60 +#define AD5766_CMD_SW_FULL_RESET 0x70 +#define AD5766_CMD_READBACK_REG(x) (0x80 | ((x) & GENMASK(3, 0))) +#define AD5766_CMD_DITHER_SIG_1 0x90 +#define AD5766_CMD_DITHER_SIG_2 0xA0 +#define AD5766_CMD_INV_DITHER 0xB0 +#define AD5766_CMD_DITHER_SCALE_1 0xC0 +#define AD5766_CMD_DITHER_SCALE_2 0xD0 + +#define AD5766_FULL_RESET_CODE 0x1234 + +enum ad5766_type { + ID_AD5766, + ID_AD5767, +}; + +enum ad5766_voltage_range { + AD5766_VOLTAGE_RANGE_M20V_0V, + AD5766_VOLTAGE_RANGE_M16V_to_0V, + AD5766_VOLTAGE_RANGE_M10V_to_0V, + AD5766_VOLTAGE_RANGE_M12V_to_14V, + AD5766_VOLTAGE_RANGE_M16V_to_10V, + AD5766_VOLTAGE_RANGE_M10V_to_6V, + AD5766_VOLTAGE_RANGE_M5V_to_5V, + AD5766_VOLTAGE_RANGE_M10V_to_10V, +}; + +/** + * struct ad5766_chip_info - chip specific information + * @num_channels: number of channels + * @channels: channel specification + */ +struct ad5766_chip_info { + unsigned int num_channels; + const struct iio_chan_spec *channels; +}; + +enum { + AD5766_DITHER_ENABLE, + AD5766_DITHER_INVERT, + AD5766_DITHER_SOURCE, +}; + +/* + * Dither signal can also be scaled. + * Available dither scale strings corresponding to "dither_scale" field in + * "struct ad5766_state". + */ +static const char * const ad5766_dither_scales[] = { + "1", + "0.75", + "0.5", + "0.25", +}; + +/** + * struct ad5766_state - driver instance specific data + * @spi: SPI device + * @lock: Lock used to restrict concurent access to SPI device + * @chip_info: Chip model specific constants + * @gpio_reset: Reset GPIO, used to reset the device + * @crt_range: Current selected output range + * @dither_enable: Power enable bit for each channel dither block (for + * example, D15 = DAC 15,D8 = DAC 8, and D0 = DAC 0) + * 0 - Normal operation, 1 - Power down + * @dither_invert: Inverts the dither signal applied to the selected DAC + * outputs + * @dither_source: Selects between 2 possible sources: + * 1: N0, 2: N1 + * Two bits are used for each channel + * @dither_scale: Two bits are used for each of the 16 channels: + * 0: 1 SCALING, 1: 0.75 SCALING, 2: 0.5 SCALING, + * 3: 0.25 SCALING. + * @data: SPI transfer buffers + */ +struct ad5766_state { + struct spi_device *spi; + struct mutex lock; + const struct ad5766_chip_info *chip_info; + struct gpio_desc *gpio_reset; + enum ad5766_voltage_range crt_range; + u16 dither_enable; + u16 dither_invert; + u32 dither_source; + u32 dither_scale; + union { + u32 d32; + u16 w16[2]; + u8 b8[4]; + } data[3] ____cacheline_aligned; +}; + +struct ad5766_span_tbl { + int min; + int max; +}; + +static const struct ad5766_span_tbl ad5766_span_tbl[] = { + [AD5766_VOLTAGE_RANGE_M20V_0V] = {-20, 0}, + [AD5766_VOLTAGE_RANGE_M16V_to_0V] = {-16, 0}, + [AD5766_VOLTAGE_RANGE_M10V_to_0V] = {-10, 0}, + [AD5766_VOLTAGE_RANGE_M12V_to_14V] = {-12, 14}, + [AD5766_VOLTAGE_RANGE_M16V_to_10V] = {-16, 10}, + [AD5766_VOLTAGE_RANGE_M10V_to_6V] = {-10, 6}, + [AD5766_VOLTAGE_RANGE_M5V_to_5V] = {-5, 5}, + [AD5766_VOLTAGE_RANGE_M10V_to_10V] = {-10, 10}, +}; + +static int __ad5766_spi_read(struct ad5766_state *st, u8 dac, int *val) +{ + int ret; + struct spi_transfer xfers[] = { + { + .tx_buf = &st->data[0].d32, + .bits_per_word = 8, + .len = 3, + .cs_change = 1, + }, { + .tx_buf = &st->data[1].d32, + .rx_buf = &st->data[2].d32, + .bits_per_word = 8, + .len = 3, + }, + }; + + st->data[0].d32 = AD5766_CMD_READBACK_REG(dac); + st->data[1].d32 = AD5766_CMD_NOP_MUX_OUT; + + ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers)); + if (ret) + return ret; + + *val = st->data[2].w16[1]; + + return ret; +} + +static int __ad5766_spi_write(struct ad5766_state *st, u8 command, u16 data) +{ + st->data[0].b8[0] = command; + put_unaligned_be16(data, &st->data[0].b8[1]); + + return spi_write(st->spi, &st->data[0].b8[0], 3); +} + +static int ad5766_read(struct iio_dev *indio_dev, u8 dac, int *val) +{ + struct ad5766_state *st = iio_priv(indio_dev); + int ret; + + mutex_lock(&st->lock); + ret = __ad5766_spi_read(st, dac, val); + mutex_unlock(&st->lock); + + return ret; +} + +static int ad5766_write(struct iio_dev *indio_dev, u8 dac, u16 data) +{ + struct ad5766_state *st = iio_priv(indio_dev); + int ret; + + mutex_lock(&st->lock); + ret = __ad5766_spi_write(st, AD5766_CMD_WR_DAC_REG(dac), data); + mutex_unlock(&st->lock); + + return ret; +} + +static int ad5766_reset(struct ad5766_state *st) +{ + int ret; + + if (st->gpio_reset) { + gpiod_set_value_cansleep(st->gpio_reset, 1); + ndelay(100); /* t_reset >= 100ns */ + gpiod_set_value_cansleep(st->gpio_reset, 0); + } else { + ret = __ad5766_spi_write(st, AD5766_CMD_SW_FULL_RESET, + AD5766_FULL_RESET_CODE); + if (ret < 0) + return ret; + } + + /* + * Minimum time between a reset and the subsequent successful write is + * typically 25 ns + */ + ndelay(25); + + return 0; +} + +static int ad5766_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long m) +{ + struct ad5766_state *st = iio_priv(indio_dev); + int ret; + + switch (m) { + case IIO_CHAN_INFO_RAW: + ret = ad5766_read(indio_dev, chan->address, val); + if (ret) + return ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_OFFSET: + *val = ad5766_span_tbl[st->crt_range].min; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = ad5766_span_tbl[st->crt_range].max - + ad5766_span_tbl[st->crt_range].min; + *val2 = st->chip_info->channels[0].scan_type.realbits; + + return IIO_VAL_FRACTIONAL_LOG2; + default: + return -EINVAL; + } +} + +static int ad5766_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, + int val2, + long info) +{ + switch (info) { + case IIO_CHAN_INFO_RAW: + { + const int max_val = GENMASK(chan->scan_type.realbits - 1, 0); + + if (val > max_val || val < 0) + return -EINVAL; + val <<= chan->scan_type.shift; + return ad5766_write(indio_dev, chan->address, val); + } + default: + return -EINVAL; + } +} + +static const struct iio_info ad5766_info = { + .read_raw = ad5766_read_raw, + .write_raw = ad5766_write_raw, +}; + +static int ad5766_get_dither_source(struct iio_dev *dev, + const struct iio_chan_spec *chan) +{ + struct ad5766_state *st = iio_priv(dev); + u32 source; + + source = st->dither_source & AD5766_DITHER_SOURCE_MASK(chan->channel); + source = source >> (chan->channel * 2); + source -= 1; + + return source; +} + +static int ad5766_set_dither_source(struct iio_dev *dev, + const struct iio_chan_spec *chan, + unsigned int source) +{ + struct ad5766_state *st = iio_priv(dev); + uint16_t val; + int ret; + + st->dither_source &= ~AD5766_DITHER_SOURCE_MASK(chan->channel); + st->dither_source |= AD5766_DITHER_SOURCE(chan->channel, source); + + val = FIELD_GET(AD5766_LOWER_WORD_SPI_MASK, st->dither_source); + ret = ad5766_write(dev, AD5766_CMD_DITHER_SIG_1, val); + if (ret) + return ret; + + val = FIELD_GET(AD5766_UPPER_WORD_SPI_MASK, st->dither_source); + + return ad5766_write(dev, AD5766_CMD_DITHER_SIG_2, val); +} + +static int ad5766_get_dither_scale(struct iio_dev *dev, + const struct iio_chan_spec *chan) +{ + struct ad5766_state *st = iio_priv(dev); + u32 scale; + + scale = st->dither_scale & AD5766_DITHER_SCALE_MASK(chan->channel); + + return (scale >> (chan->channel * 2)); +} + +static int ad5766_set_dither_scale(struct iio_dev *dev, + const struct iio_chan_spec *chan, + unsigned int scale) +{ + int ret; + struct ad5766_state *st = iio_priv(dev); + uint16_t val; + + st->dither_scale &= ~AD5766_DITHER_SCALE_MASK(chan->channel); + st->dither_scale |= AD5766_DITHER_SCALE(chan->channel, scale); + + val = FIELD_GET(AD5766_LOWER_WORD_SPI_MASK, st->dither_scale); + ret = ad5766_write(dev, AD5766_CMD_DITHER_SCALE_1, val); + if (ret) + return ret; + val = FIELD_GET(AD5766_UPPER_WORD_SPI_MASK, st->dither_scale); + + return ad5766_write(dev, AD5766_CMD_DITHER_SCALE_2, val); +} + +static const struct iio_enum ad5766_dither_scale_enum = { + .items = ad5766_dither_scales, + .num_items = ARRAY_SIZE(ad5766_dither_scales), + .set = ad5766_set_dither_scale, + .get = ad5766_get_dither_scale, +}; + +static ssize_t ad5766_read_ext(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + char *buf) +{ + struct ad5766_state *st = iio_priv(indio_dev); + + switch (private) { + case AD5766_DITHER_ENABLE: + return sprintf(buf, "%u\n", + !(st->dither_enable & BIT(chan->channel))); + break; + case AD5766_DITHER_INVERT: + return sprintf(buf, "%u\n", + !!(st->dither_invert & BIT(chan->channel))); + break; + case AD5766_DITHER_SOURCE: + return sprintf(buf, "%d\n", + ad5766_get_dither_source(indio_dev, chan)); + default: + return -EINVAL; + } +} + +static ssize_t ad5766_write_ext(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct ad5766_state *st = iio_priv(indio_dev); + bool readin; + int ret; + + ret = kstrtobool(buf, &readin); + if (ret) + return ret; + + switch (private) { + case AD5766_DITHER_ENABLE: + st->dither_enable &= ~AD5766_DITHER_ENABLE_MASK(chan->channel); + st->dither_enable |= AD5766_DITHER_ENABLE(chan->channel, + readin); + ret = ad5766_write(indio_dev, AD5766_CMD_WR_PWR_DITHER, + st->dither_enable); + break; + case AD5766_DITHER_INVERT: + st->dither_invert &= ~AD5766_DITHER_INVERT_MASK(chan->channel); + st->dither_invert |= AD5766_DITHER_INVERT(chan->channel, + readin); + ret = ad5766_write(indio_dev, AD5766_CMD_INV_DITHER, + st->dither_invert); + break; + case AD5766_DITHER_SOURCE: + ret = ad5766_set_dither_source(indio_dev, chan, readin); + break; + default: + return -EINVAL; + } + + return ret ? ret : len; +} + +#define _AD5766_CHAN_EXT_INFO(_name, _what, _shared) { \ + .name = _name, \ + .read = ad5766_read_ext, \ + .write = ad5766_write_ext, \ + .private = _what, \ + .shared = _shared, \ +} + +#define IIO_ENUM_AVAILABLE_SHARED(_name, _shared, _e) \ +{ \ + .name = (_name "_available"), \ + .shared = _shared, \ + .read = iio_enum_available_read, \ + .private = (uintptr_t)(_e), \ +} + +static const struct iio_chan_spec_ext_info ad5766_ext_info[] = { + + _AD5766_CHAN_EXT_INFO("dither_enable", AD5766_DITHER_ENABLE, + IIO_SEPARATE), + _AD5766_CHAN_EXT_INFO("dither_invert", AD5766_DITHER_INVERT, + IIO_SEPARATE), + _AD5766_CHAN_EXT_INFO("dither_source", AD5766_DITHER_SOURCE, + IIO_SEPARATE), + IIO_ENUM("dither_scale", IIO_SEPARATE, &ad5766_dither_scale_enum), + IIO_ENUM_AVAILABLE_SHARED("dither_scale", + IIO_SEPARATE, + &ad5766_dither_scale_enum), + {} +}; + +#define AD576x_CHANNEL(_chan, _bits) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .output = 1, \ + .channel = (_chan), \ + .address = (_chan), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | \ + BIT(IIO_CHAN_INFO_SCALE), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = (_bits), \ + .storagebits = 16, \ + .shift = 16 - (_bits), \ + }, \ + .ext_info = ad5766_ext_info, \ +} + +#define DECLARE_AD576x_CHANNELS(_name, _bits) \ +const struct iio_chan_spec _name[] = { \ + AD576x_CHANNEL(0, (_bits)), \ + AD576x_CHANNEL(1, (_bits)), \ + AD576x_CHANNEL(2, (_bits)), \ + AD576x_CHANNEL(3, (_bits)), \ + AD576x_CHANNEL(4, (_bits)), \ + AD576x_CHANNEL(5, (_bits)), \ + AD576x_CHANNEL(6, (_bits)), \ + AD576x_CHANNEL(7, (_bits)), \ + AD576x_CHANNEL(8, (_bits)), \ + AD576x_CHANNEL(9, (_bits)), \ + AD576x_CHANNEL(10, (_bits)), \ + AD576x_CHANNEL(11, (_bits)), \ + AD576x_CHANNEL(12, (_bits)), \ + AD576x_CHANNEL(13, (_bits)), \ + AD576x_CHANNEL(14, (_bits)), \ + AD576x_CHANNEL(15, (_bits)), \ +} + +static DECLARE_AD576x_CHANNELS(ad5766_channels, 16); +static DECLARE_AD576x_CHANNELS(ad5767_channels, 12); + +static const struct ad5766_chip_info ad5766_chip_infos[] = { + [ID_AD5766] = { + .num_channels = ARRAY_SIZE(ad5766_channels), + .channels = ad5766_channels, + }, + [ID_AD5767] = { + .num_channels = ARRAY_SIZE(ad5767_channels), + .channels = ad5767_channels, + }, +}; + +static int ad5766_get_output_range(struct ad5766_state *st) +{ + int i, ret, min, max, tmp[2]; + + ret = device_property_read_u32_array(&st->spi->dev, + "output-range-voltage", + tmp, 2); + if (ret) + return ret; + + min = tmp[0] / 1000; + max = tmp[1] / 1000; + for (i = 0; i < ARRAY_SIZE(ad5766_span_tbl); i++) { + if (ad5766_span_tbl[i].min != min || + ad5766_span_tbl[i].max != max) + continue; + + st->crt_range = i; + + return 0; + } + + return -EINVAL; +} + +static int ad5766_default_setup(struct ad5766_state *st) +{ + uint16_t val; + int ret, i; + + /* Always issue a reset before writing to the span register. */ + ret = ad5766_reset(st); + if (ret) + return ret; + + ret = ad5766_get_output_range(st); + if (ret) + return ret; + + /* Dither power down */ + st->dither_enable = GENMASK(15, 0); + ret = __ad5766_spi_write(st, AD5766_CMD_WR_PWR_DITHER, + st->dither_enable); + if (ret) + return ret; + + st->dither_source = 0; + for (i = 0; i < ARRAY_SIZE(ad5766_channels); i++) + st->dither_source |= AD5766_DITHER_SOURCE(i, 0); + val = FIELD_GET(AD5766_LOWER_WORD_SPI_MASK, st->dither_source); + ret = __ad5766_spi_write(st, AD5766_CMD_DITHER_SIG_1, val); + if (ret) + return ret; + + val = FIELD_GET(AD5766_UPPER_WORD_SPI_MASK, st->dither_source); + ret = __ad5766_spi_write(st, AD5766_CMD_DITHER_SIG_2, val); + if (ret) + return ret; + + st->dither_scale = 0; + val = FIELD_GET(AD5766_LOWER_WORD_SPI_MASK, st->dither_scale); + ret = __ad5766_spi_write(st, AD5766_CMD_DITHER_SCALE_1, val); + if (ret) + return ret; + + val = FIELD_GET(AD5766_UPPER_WORD_SPI_MASK, st->dither_scale); + ret = __ad5766_spi_write(st, AD5766_CMD_DITHER_SCALE_2, val); + if (ret) + return ret; + + st->dither_invert = 0; + ret = __ad5766_spi_write(st, AD5766_CMD_INV_DITHER, st->dither_invert); + if (ret) + return ret; + + return __ad5766_spi_write(st, AD5766_CMD_SPAN_REG, st->crt_range); +} + +static int ad5766_probe(struct spi_device *spi) +{ + enum ad5766_type type; + struct iio_dev *indio_dev; + struct ad5766_state *st; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + mutex_init(&st->lock); + + st->spi = spi; + type = spi_get_device_id(spi)->driver_data; + st->chip_info = &ad5766_chip_infos[type]; + + indio_dev->channels = st->chip_info->channels; + indio_dev->num_channels = st->chip_info->num_channels; + indio_dev->info = &ad5766_info; + indio_dev->dev.parent = &spi->dev; + indio_dev->dev.of_node = spi->dev.of_node; + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->modes = INDIO_DIRECT_MODE; + + st->gpio_reset = devm_gpiod_get_optional(&st->spi->dev, "reset", + GPIOD_OUT_LOW); + if (IS_ERR(st->gpio_reset)) + return PTR_ERR(st->gpio_reset); + + ret = ad5766_default_setup(st); + if (ret) + return ret; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id ad5766_dt_match[] = { + { .compatible = "adi,ad5766" }, + { .compatible = "adi,ad5767" }, + {} +}; +MODULE_DEVICE_TABLE(of, ad5766_dt_match); + +static const struct spi_device_id ad5766_spi_ids[] = { + { "ad5766", ID_AD5766 }, + { "ad5767", ID_AD5767 }, + {} +}; +MODULE_DEVICE_TABLE(spi, ad5766_spi_ids); + +static struct spi_driver ad5766_driver = { + .driver = { + .name = "ad5766", + .of_match_table = ad5766_dt_match, + }, + .probe = ad5766_probe, + .id_table = ad5766_spi_ids, +}; +module_spi_driver(ad5766_driver); + +MODULE_AUTHOR("Denis-Gabriel Gheorghescu "); +MODULE_DESCRIPTION("Analog Devices AD5766/AD5767 DACs"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3