diff options
Diffstat (limited to 'drivers/iio/adc/ti-adc128s052.c')
| -rw-r--r-- | drivers/iio/adc/ti-adc128s052.c | 286 |
1 files changed, 286 insertions, 0 deletions
diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c new file mode 100644 index 000000000000..4ae65793ad9b --- /dev/null +++ b/drivers/iio/adc/ti-adc128s052.c @@ -0,0 +1,286 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2014 Angelo Compagnucci <angelo.compagnucci@gmail.com> + * + * Driver for Texas Instruments' ADC128S052, ADC122S021 and ADC124S021 ADC chip. + * Datasheets can be found here: + * https://www.ti.com/lit/ds/symlink/adc128s052.pdf + * https://www.ti.com/lit/ds/symlink/adc122s021.pdf + * https://www.ti.com/lit/ds/symlink/adc124s021.pdf + */ + +#include <linux/cleanup.h> +#include <linux/err.h> +#include <linux/iio/iio.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h> + +struct adc128_configuration { + const struct iio_chan_spec *channels; + u8 num_channels; + const char *refname; + int num_other_regulators; + const char * const (*other_regulators)[]; +}; + +struct adc128 { + struct spi_device *spi; + + /* + * Serialize the SPI 'write-channel + read data' accesses and protect + * the shared buffer. + */ + struct mutex lock; + int vref_mv; + union { + __be16 buffer16; + u8 buffer[2]; + } __aligned(IIO_DMA_MINALIGN); +}; + +static int adc128_adc_conversion(struct adc128 *adc, u8 channel) +{ + int ret; + + guard(mutex)(&adc->lock); + + adc->buffer[0] = channel << 3; + adc->buffer[1] = 0; + + ret = spi_write(adc->spi, &adc->buffer, sizeof(adc->buffer)); + if (ret < 0) + return ret; + + ret = spi_read(adc->spi, &adc->buffer16, sizeof(adc->buffer16)); + if (ret < 0) + return ret; + + return be16_to_cpu(adc->buffer16) & 0xFFF; +} + +static int adc128_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, int *val, + int *val2, long mask) +{ + struct adc128 *adc = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + + ret = adc128_adc_conversion(adc, channel->channel); + if (ret < 0) + return ret; + + *val = ret; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + + *val = adc->vref_mv; + *val2 = 12; + return IIO_VAL_FRACTIONAL_LOG2; + + default: + return -EINVAL; + } + +} + +#define ADC128_VOLTAGE_CHANNEL(num) \ + { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (num), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \ + } + +static const struct iio_chan_spec simple_1chan_adc_channels[] = { + ADC128_VOLTAGE_CHANNEL(0), +}; + +static const struct iio_chan_spec simple_2chan_adc_channels[] = { + ADC128_VOLTAGE_CHANNEL(0), + ADC128_VOLTAGE_CHANNEL(1), +}; + +static const struct iio_chan_spec simple_4chan_adc_channels[] = { + ADC128_VOLTAGE_CHANNEL(0), + ADC128_VOLTAGE_CHANNEL(1), + ADC128_VOLTAGE_CHANNEL(2), + ADC128_VOLTAGE_CHANNEL(3), +}; + +static const struct iio_chan_spec simple_8chan_adc_channels[] = { + ADC128_VOLTAGE_CHANNEL(0), + ADC128_VOLTAGE_CHANNEL(1), + ADC128_VOLTAGE_CHANNEL(2), + ADC128_VOLTAGE_CHANNEL(3), + ADC128_VOLTAGE_CHANNEL(4), + ADC128_VOLTAGE_CHANNEL(5), + ADC128_VOLTAGE_CHANNEL(6), + ADC128_VOLTAGE_CHANNEL(7), +}; + +static const char * const bd79104_regulators[] = { "iovdd" }; + +static const struct adc128_configuration adc122s_config = { + .channels = simple_2chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_2chan_adc_channels), + .refname = "vref", +}; + +static const struct adc128_configuration adc124s_config = { + .channels = simple_4chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_4chan_adc_channels), + .refname = "vref", +}; + +static const struct adc128_configuration adc128s_config = { + .channels = simple_8chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_8chan_adc_channels), + .refname = "vref", +}; + +static const struct adc128_configuration bd79100_config = { + .channels = simple_1chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_1chan_adc_channels), + .refname = "vdd", + .other_regulators = &bd79104_regulators, + .num_other_regulators = 1, +}; + +static const struct adc128_configuration bd79101_config = { + .channels = simple_2chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_2chan_adc_channels), + .refname = "vdd", + .other_regulators = &bd79104_regulators, + .num_other_regulators = 1, +}; + +static const struct adc128_configuration bd79102_config = { + .channels = simple_4chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_4chan_adc_channels), + .refname = "vdd", + .other_regulators = &bd79104_regulators, + .num_other_regulators = 1, +}; + +static const struct adc128_configuration bd79104_config = { + .channels = simple_8chan_adc_channels, + .num_channels = ARRAY_SIZE(simple_8chan_adc_channels), + .refname = "vdd", + .other_regulators = &bd79104_regulators, + .num_other_regulators = 1, +}; + +static const struct iio_info adc128_info = { + .read_raw = adc128_read_raw, +}; + +static int adc128_probe(struct spi_device *spi) +{ + const struct adc128_configuration *config; + struct iio_dev *indio_dev; + struct adc128 *adc; + int ret; + + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc)); + if (!indio_dev) + return -ENOMEM; + + adc = iio_priv(indio_dev); + adc->spi = spi; + + indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &adc128_info; + + config = spi_get_device_match_data(spi); + + indio_dev->channels = config->channels; + indio_dev->num_channels = config->num_channels; + + ret = devm_regulator_get_enable_read_voltage(&spi->dev, + config->refname); + if (ret < 0) + return dev_err_probe(&spi->dev, ret, + "failed to read '%s' voltage", + config->refname); + + adc->vref_mv = ret / 1000; + + if (config->num_other_regulators) { + ret = devm_regulator_bulk_get_enable(&spi->dev, + config->num_other_regulators, + *config->other_regulators); + if (ret) + return dev_err_probe(&spi->dev, ret, + "Failed to enable regulators\n"); + } + + ret = devm_mutex_init(&spi->dev, &adc->lock); + if (ret) + return ret; + + return devm_iio_device_register(&spi->dev, indio_dev); +} + +static const struct of_device_id adc128_of_match[] = { + { .compatible = "ti,adc128s052", .data = &adc128s_config }, + { .compatible = "ti,adc122s021", .data = &adc122s_config }, + { .compatible = "ti,adc122s051", .data = &adc122s_config }, + { .compatible = "ti,adc122s101", .data = &adc122s_config }, + { .compatible = "ti,adc124s021", .data = &adc124s_config }, + { .compatible = "ti,adc124s051", .data = &adc124s_config }, + { .compatible = "ti,adc124s101", .data = &adc124s_config }, + { .compatible = "rohm,bd79100", .data = &bd79100_config }, + { .compatible = "rohm,bd79101", .data = &bd79101_config }, + { .compatible = "rohm,bd79102", .data = &bd79102_config }, + { .compatible = "rohm,bd79103", .data = &bd79104_config }, + { .compatible = "rohm,bd79104", .data = &bd79104_config }, + { } +}; +MODULE_DEVICE_TABLE(of, adc128_of_match); + +static const struct spi_device_id adc128_id[] = { + { "adc128s052", (kernel_ulong_t)&adc128s_config }, + { "adc122s021", (kernel_ulong_t)&adc122s_config }, + { "adc122s051", (kernel_ulong_t)&adc122s_config }, + { "adc122s101", (kernel_ulong_t)&adc122s_config }, + { "adc124s021", (kernel_ulong_t)&adc124s_config }, + { "adc124s051", (kernel_ulong_t)&adc124s_config }, + { "adc124s101", (kernel_ulong_t)&adc124s_config }, + { "bd79100", (kernel_ulong_t)&bd79100_config }, + { "bd79101", (kernel_ulong_t)&bd79101_config }, + { "bd79102", (kernel_ulong_t)&bd79102_config }, + { "bd79103", (kernel_ulong_t)&bd79104_config }, + { "bd79104", (kernel_ulong_t)&bd79104_config }, + { } +}; +MODULE_DEVICE_TABLE(spi, adc128_id); + +static const struct acpi_device_id adc128_acpi_match[] = { + { "AANT1280", (kernel_ulong_t)&adc124s_config }, + { } +}; +MODULE_DEVICE_TABLE(acpi, adc128_acpi_match); + +static struct spi_driver adc128_driver = { + .driver = { + .name = "adc128s052", + .of_match_table = adc128_of_match, + .acpi_match_table = adc128_acpi_match, + }, + .probe = adc128_probe, + .id_table = adc128_id, +}; +module_spi_driver(adc128_driver); + +MODULE_AUTHOR("Angelo Compagnucci <angelo.compagnucci@gmail.com>"); +MODULE_DESCRIPTION("Texas Instruments ADC128S052"); +MODULE_LICENSE("GPL v2"); |