From 6a533f56b020d3941da8b8d3a521fc800ffc29ea Mon Sep 17 00:00:00 2001 From: Pop Ioan Daniel Date: Thu, 5 Jun 2025 18:09:43 +0300 Subject: [PATCH] iio: adc: ad7405: add ad7405 driver MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Add support for the AD7405/ADUM770x, a high performance isolated ADC, 1-channel, 16-bit with a second-order Σ-Δ modulator that converts an analog input signal into a high speed, single-bit data stream. Signed-off-by: Pop Ioan Daniel Reviewed-by: Nuno Sá Link: https://patch.msgid.link/20250605150948.3091827-6-pop.ioan-daniel@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/adc/Kconfig | 10 ++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ad7405.c | 253 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 264 insertions(+) create mode 100644 drivers/iio/adc/ad7405.c diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 3bd03df9a976..799437f918df 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -266,6 +266,16 @@ config AD7380 To compile this driver as a module, choose M here: the module will be called ad7380. +config AD7405 + tristate "Analog Device AD7405 ADC Driver" + depends on IIO_BACKEND + help + Say yes here to build support for Analog Devices AD7405, ADUM7701, + ADUM7702, ADUM7703 analog to digital converters (ADC). + + To compile this driver as a module, choose M here: the module will be + called ad7405. + config AD7476 tristate "Analog Devices AD7476 1-channel ADCs driver and other similar devices from AD and TI" depends on SPI diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 6516ccb4d63b..15c60544a475 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_AD7291) += ad7291.o obj-$(CONFIG_AD7292) += ad7292.o obj-$(CONFIG_AD7298) += ad7298.o obj-$(CONFIG_AD7380) += ad7380.o +obj-$(CONFIG_AD7405) += ad7405.o obj-$(CONFIG_AD7476) += ad7476.o obj-$(CONFIG_AD7606_IFACE_PARALLEL) += ad7606_par.o obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o diff --git a/drivers/iio/adc/ad7405.c b/drivers/iio/adc/ad7405.c new file mode 100644 index 000000000000..9adf85a732ce --- /dev/null +++ b/drivers/iio/adc/ad7405.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Analog Devices AD7405 driver + * + * Copyright 2025 Analog Devices Inc. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +static const unsigned int ad7405_dec_rates_range[] = { + 32, 1, 4096, +}; + +struct ad7405_chip_info { + const char *name; + const unsigned int full_scale_mv; +}; + +struct ad7405_state { + struct iio_backend *back; + const struct ad7405_chip_info *info; + unsigned int ref_frequency; + unsigned int dec_rate; +}; + +static int ad7405_set_dec_rate(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int dec_rate) +{ + struct ad7405_state *st = iio_priv(indio_dev); + int ret; + + if (dec_rate > 4096 || dec_rate < 32) + return -EINVAL; + + if (!iio_device_claim_direct(indio_dev)) + return -EBUSY; + + ret = iio_backend_oversampling_ratio_set(st->back, chan->scan_index, dec_rate); + iio_device_release_direct(indio_dev); + + if (ret < 0) + return ret; + + st->dec_rate = dec_rate; + + return 0; +} + +static int ad7405_read_raw(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, int *val, + int *val2, long info) +{ + struct ad7405_state *st = iio_priv(indio_dev); + + switch (info) { + case IIO_CHAN_INFO_SCALE: + *val = st->info->full_scale_mv; + *val2 = indio_dev->channels[0].scan_type.realbits - 1; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = st->dec_rate; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SAMP_FREQ: + *val = DIV_ROUND_CLOSEST_ULL(st->ref_frequency, st->dec_rate); + return IIO_VAL_INT; + case IIO_CHAN_INFO_OFFSET: + *val = -(1 << (indio_dev->channels[0].scan_type.realbits - 1)); + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int ad7405_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_OVERSAMPLING_RATIO: + if (val < 0) + return -EINVAL; + return ad7405_set_dec_rate(indio_dev, chan, val); + default: + return -EINVAL; + } +} + +static int ad7405_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long info) +{ + switch (info) { + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *vals = ad7405_dec_rates_range; + *type = IIO_VAL_INT; + return IIO_AVAIL_RANGE; + default: + return -EINVAL; + } +} + +static const struct iio_info ad7405_iio_info = { + .read_raw = &ad7405_read_raw, + .write_raw = &ad7405_write_raw, + .read_avail = &ad7405_read_avail, +}; + +static const struct iio_chan_spec ad7405_channel = { + .type = IIO_VOLTAGE, + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .info_mask_shared_by_all = IIO_CHAN_INFO_SAMP_FREQ | + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), + .info_mask_shared_by_all_available = + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), + .indexed = 1, + .channel = 0, + .channel2 = 1, + .differential = 1, + .scan_index = 0, + .scan_type = { + .sign = 'u', + .realbits = 16, + .storagebits = 16, + }, +}; + +static const struct ad7405_chip_info ad7405_chip_info = { + .name = "ad7405", + .full_scale_mv = 320, +}; + +static const struct ad7405_chip_info adum7701_chip_info = { + .name = "adum7701", + .full_scale_mv = 320, +}; + +static const struct ad7405_chip_info adum7702_chip_info = { + .name = "adum7702", + .full_scale_mv = 64, +}; + +static const struct ad7405_chip_info adum7703_chip_info = { + .name = "adum7703", + .full_scale_mv = 320, +}; + +static const char * const ad7405_power_supplies[] = { + "vdd1", "vdd2", +}; + +static int ad7405_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *indio_dev; + struct ad7405_state *st; + struct clk *clk; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + + st->info = device_get_match_data(dev); + if (!st->info) + return dev_err_probe(dev, -EINVAL, "no chip info\n"); + + ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(ad7405_power_supplies), + ad7405_power_supplies); + if (ret) + return dev_err_probe(dev, ret, "failed to get and enable supplies"); + + clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + st->ref_frequency = clk_get_rate(clk); + if (!st->ref_frequency) + return -EINVAL; + + indio_dev->name = st->info->name; + indio_dev->channels = &ad7405_channel; + indio_dev->num_channels = 1; + indio_dev->info = &ad7405_iio_info; + + st->back = devm_iio_backend_get(dev, NULL); + if (IS_ERR(st->back)) + return dev_err_probe(dev, PTR_ERR(st->back), + "failed to get IIO backend"); + + ret = iio_backend_chan_enable(st->back, 0); + if (ret) + return ret; + + ret = devm_iio_backend_request_buffer(dev, st->back, indio_dev); + if (ret) + return ret; + + ret = devm_iio_backend_enable(dev, st->back); + if (ret) + return ret; + + /* + * Set 256 decimation rate. The default value in the AXI_ADC register + * is 0, so we set the register with a decimation rate value that is + * functional for all parts. + */ + ret = ad7405_set_dec_rate(indio_dev, &indio_dev->channels[0], 256); + if (ret) + return ret; + + return devm_iio_device_register(dev, indio_dev); +} + +static const struct of_device_id ad7405_of_match[] = { + { .compatible = "adi,ad7405", .data = &ad7405_chip_info, }, + { .compatible = "adi,adum7701", .data = &adum7701_chip_info, }, + { .compatible = "adi,adum7702", .data = &adum7702_chip_info, }, + { .compatible = "adi,adum7703", .data = &adum7703_chip_info, }, + { } +}; +MODULE_DEVICE_TABLE(of, ad7405_of_match); + +static struct platform_driver ad7405_driver = { + .driver = { + .name = "ad7405", + .of_match_table = ad7405_of_match, + }, + .probe = ad7405_probe, +}; +module_platform_driver(ad7405_driver); + +MODULE_AUTHOR("Dragos Bogdan "); +MODULE_AUTHOR("Pop Ioan Daniel "); +MODULE_DESCRIPTION("Analog Devices AD7405 driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("IIO_BACKEND"); -- 2.51.0