| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Maxim MAX11205 16-Bit Delta-Sigma ADC |
| * |
| * Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX1240-max11205.pdf |
| * Copyright (C) 2022 Analog Devices, Inc. |
| * Author: Ramona Bolboaca <ramona.bolboaca@analog.com> |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/module.h> |
| #include <linux/regulator/consumer.h> |
| #include <linux/spi/spi.h> |
| |
| #include <linux/iio/iio.h> |
| #include <linux/iio/adc/ad_sigma_delta.h> |
| |
| #define MAX11205_BIT_SCALE 15 |
| #define MAX11205A_OUT_DATA_RATE 116 |
| #define MAX11205B_OUT_DATA_RATE 13 |
| |
| enum max11205_chip_type { |
| TYPE_MAX11205A, |
| TYPE_MAX11205B, |
| }; |
| |
| struct max11205_chip_info { |
| unsigned int out_data_rate; |
| const char *name; |
| }; |
| |
| struct max11205_state { |
| const struct max11205_chip_info *chip_info; |
| struct regulator *vref; |
| struct ad_sigma_delta sd; |
| }; |
| |
| static const struct ad_sigma_delta_info max11205_sigma_delta_info = { |
| .has_registers = false, |
| }; |
| |
| static int max11205_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| struct max11205_state *st = iio_priv(indio_dev); |
| int reg_mv; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| return ad_sigma_delta_single_conversion(indio_dev, chan, val); |
| case IIO_CHAN_INFO_SCALE: |
| reg_mv = regulator_get_voltage(st->vref); |
| if (reg_mv < 0) |
| return reg_mv; |
| reg_mv /= 1000; |
| *val = reg_mv; |
| *val2 = MAX11205_BIT_SCALE; |
| return IIO_VAL_FRACTIONAL_LOG2; |
| case IIO_CHAN_INFO_SAMP_FREQ: |
| *val = st->chip_info->out_data_rate; |
| return IIO_VAL_INT; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static const struct iio_info max11205_iio_info = { |
| .read_raw = max11205_read_raw, |
| .validate_trigger = ad_sd_validate_trigger, |
| }; |
| |
| static const struct iio_chan_spec max11205_channels[] = { |
| { |
| .type = IIO_VOLTAGE, |
| .indexed = 1, |
| .scan_type = { |
| .sign = 's', |
| .realbits = 16, |
| .storagebits = 16, |
| .endianness = IIO_BE, |
| }, |
| .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | |
| BIT(IIO_CHAN_INFO_SAMP_FREQ) | |
| BIT(IIO_CHAN_INFO_SCALE), |
| }, |
| }; |
| |
| static const struct max11205_chip_info max11205_chip_info[] = { |
| [TYPE_MAX11205A] = { |
| .out_data_rate = MAX11205A_OUT_DATA_RATE, |
| .name = "max11205a", |
| }, |
| [TYPE_MAX11205B] = { |
| .out_data_rate = MAX11205B_OUT_DATA_RATE, |
| .name = "max11205b", |
| }, |
| }; |
| |
| static void max11205_reg_disable(void *reg) |
| { |
| regulator_disable(reg); |
| } |
| |
| static int max11205_probe(struct spi_device *spi) |
| { |
| struct max11205_state *st; |
| struct iio_dev *indio_dev; |
| int ret; |
| |
| indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| st = iio_priv(indio_dev); |
| |
| ad_sd_init(&st->sd, indio_dev, spi, &max11205_sigma_delta_info); |
| |
| st->chip_info = device_get_match_data(&spi->dev); |
| if (!st->chip_info) |
| st->chip_info = |
| (const struct max11205_chip_info *)spi_get_device_id(spi)->driver_data; |
| |
| indio_dev->name = st->chip_info->name; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| indio_dev->channels = max11205_channels; |
| indio_dev->num_channels = 1; |
| indio_dev->info = &max11205_iio_info; |
| |
| st->vref = devm_regulator_get(&spi->dev, "vref"); |
| if (IS_ERR(st->vref)) |
| return dev_err_probe(&spi->dev, PTR_ERR(st->vref), |
| "Failed to get vref regulator\n"); |
| |
| ret = regulator_enable(st->vref); |
| if (ret) |
| return ret; |
| |
| ret = devm_add_action_or_reset(&spi->dev, max11205_reg_disable, st->vref); |
| if (ret) |
| return ret; |
| |
| ret = devm_ad_sd_setup_buffer_and_trigger(&spi->dev, indio_dev); |
| if (ret) |
| return ret; |
| |
| return devm_iio_device_register(&spi->dev, indio_dev); |
| } |
| |
| static const struct spi_device_id max11205_spi_ids[] = { |
| { "max11205a", (kernel_ulong_t)&max11205_chip_info[TYPE_MAX11205A] }, |
| { "max11205b", (kernel_ulong_t)&max11205_chip_info[TYPE_MAX11205B] }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(spi, max11205_spi_ids); |
| |
| static const struct of_device_id max11205_dt_ids[] = { |
| { |
| .compatible = "maxim,max11205a", |
| .data = &max11205_chip_info[TYPE_MAX11205A], |
| }, |
| { |
| .compatible = "maxim,max11205b", |
| .data = &max11205_chip_info[TYPE_MAX11205B], |
| }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, max11205_dt_ids); |
| |
| static struct spi_driver max11205_spi_driver = { |
| .driver = { |
| .name = "max11205", |
| .of_match_table = max11205_dt_ids, |
| }, |
| .probe = max11205_probe, |
| .id_table = max11205_spi_ids, |
| }; |
| module_spi_driver(max11205_spi_driver); |
| |
| MODULE_AUTHOR("Ramona Bolboaca <ramona.bolboaca@analog.com>"); |
| MODULE_DESCRIPTION("MAX11205 ADC driver"); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_IMPORT_NS(IIO_AD_SIGMA_DELTA); |