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-rw-r--r--drivers/iio/adc/ti-adc128s052.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c
new file mode 100644
index 0000000000..a456ea7846
--- /dev/null
+++ b/drivers/iio/adc/ti-adc128s052.c
@@ -0,0 +1,222 @@
+// 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/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;
+};
+
+struct adc128 {
+ struct spi_device *spi;
+
+ struct regulator *reg;
+ struct mutex lock;
+
+ u8 buffer[2] __aligned(IIO_DMA_MINALIGN);
+};
+
+static int adc128_adc_conversion(struct adc128 *adc, u8 channel)
+{
+ int ret;
+
+ mutex_lock(&adc->lock);
+
+ adc->buffer[0] = channel << 3;
+ adc->buffer[1] = 0;
+
+ ret = spi_write(adc->spi, &adc->buffer, 2);
+ if (ret < 0) {
+ mutex_unlock(&adc->lock);
+ return ret;
+ }
+
+ ret = spi_read(adc->spi, &adc->buffer, 2);
+
+ mutex_unlock(&adc->lock);
+
+ if (ret < 0)
+ return ret;
+
+ return ((adc->buffer[0] << 8 | adc->buffer[1]) & 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:
+
+ ret = regulator_get_voltage(adc->reg);
+ if (ret < 0)
+ return ret;
+
+ *val = ret / 1000;
+ *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 adc128s052_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 struct iio_chan_spec adc122s021_channels[] = {
+ ADC128_VOLTAGE_CHANNEL(0),
+ ADC128_VOLTAGE_CHANNEL(1),
+};
+
+static const struct iio_chan_spec adc124s021_channels[] = {
+ ADC128_VOLTAGE_CHANNEL(0),
+ ADC128_VOLTAGE_CHANNEL(1),
+ ADC128_VOLTAGE_CHANNEL(2),
+ ADC128_VOLTAGE_CHANNEL(3),
+};
+
+static const struct adc128_configuration adc128_config[] = {
+ { adc128s052_channels, ARRAY_SIZE(adc128s052_channels) },
+ { adc122s021_channels, ARRAY_SIZE(adc122s021_channels) },
+ { adc124s021_channels, ARRAY_SIZE(adc124s021_channels) },
+};
+
+static const struct iio_info adc128_info = {
+ .read_raw = adc128_read_raw,
+};
+
+static void adc128_disable_regulator(void *reg)
+{
+ regulator_disable(reg);
+}
+
+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;
+
+ adc->reg = devm_regulator_get(&spi->dev, "vref");
+ if (IS_ERR(adc->reg))
+ return PTR_ERR(adc->reg);
+
+ ret = regulator_enable(adc->reg);
+ if (ret < 0)
+ return ret;
+ ret = devm_add_action_or_reset(&spi->dev, adc128_disable_regulator,
+ adc->reg);
+ if (ret)
+ return ret;
+
+ mutex_init(&adc->lock);
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct of_device_id adc128_of_match[] = {
+ { .compatible = "ti,adc128s052", .data = &adc128_config[0] },
+ { .compatible = "ti,adc122s021", .data = &adc128_config[1] },
+ { .compatible = "ti,adc122s051", .data = &adc128_config[1] },
+ { .compatible = "ti,adc122s101", .data = &adc128_config[1] },
+ { .compatible = "ti,adc124s021", .data = &adc128_config[2] },
+ { .compatible = "ti,adc124s051", .data = &adc128_config[2] },
+ { .compatible = "ti,adc124s101", .data = &adc128_config[2] },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, adc128_of_match);
+
+static const struct spi_device_id adc128_id[] = {
+ { "adc128s052", (kernel_ulong_t)&adc128_config[0] },
+ { "adc122s021", (kernel_ulong_t)&adc128_config[1] },
+ { "adc122s051", (kernel_ulong_t)&adc128_config[1] },
+ { "adc122s101", (kernel_ulong_t)&adc128_config[1] },
+ { "adc124s021", (kernel_ulong_t)&adc128_config[2] },
+ { "adc124s051", (kernel_ulong_t)&adc128_config[2] },
+ { "adc124s101", (kernel_ulong_t)&adc128_config[2] },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, adc128_id);
+
+static const struct acpi_device_id adc128_acpi_match[] = {
+ { "AANT1280", (kernel_ulong_t)&adc128_config[2] },
+ { }
+};
+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");