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-rw-r--r--drivers/iio/adc/ti-adc161s626.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/drivers/iio/adc/ti-adc161s626.c b/drivers/iio/adc/ti-adc161s626.c
new file mode 100644
index 000000000..b789891dc
--- /dev/null
+++ b/drivers/iio/adc/ti-adc161s626.c
@@ -0,0 +1,256 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * ti-adc161s626.c - Texas Instruments ADC161S626 1-channel differential ADC
+ *
+ * ADC Devices Supported:
+ * adc141s626 - 14-bit ADC
+ * adc161s626 - 16-bit ADC
+ *
+ * Copyright (C) 2016-2018
+ * Author: Matt Ranostay <matt.ranostay@konsulko.com>
+ */
+
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/spi/spi.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/regulator/consumer.h>
+
+#define TI_ADC_DRV_NAME "ti-adc161s626"
+
+enum {
+ TI_ADC141S626,
+ TI_ADC161S626,
+};
+
+static const struct iio_chan_spec ti_adc141s626_channels[] = {
+ {
+ .type = IIO_VOLTAGE,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 's',
+ .realbits = 14,
+ .storagebits = 16,
+ },
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
+static const struct iio_chan_spec ti_adc161s626_channels[] = {
+ {
+ .type = IIO_VOLTAGE,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 's',
+ .realbits = 16,
+ .storagebits = 16,
+ },
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
+struct ti_adc_data {
+ struct iio_dev *indio_dev;
+ struct spi_device *spi;
+ struct regulator *ref;
+
+ u8 read_size;
+ u8 shift;
+
+ u8 buffer[16] __aligned(IIO_DMA_MINALIGN);
+};
+
+static int ti_adc_read_measurement(struct ti_adc_data *data,
+ struct iio_chan_spec const *chan, int *val)
+{
+ int ret;
+
+ switch (data->read_size) {
+ case 2: {
+ __be16 buf;
+
+ ret = spi_read(data->spi, (void *) &buf, 2);
+ if (ret)
+ return ret;
+
+ *val = be16_to_cpu(buf);
+ break;
+ }
+ case 3: {
+ __be32 buf;
+
+ ret = spi_read(data->spi, (void *) &buf, 3);
+ if (ret)
+ return ret;
+
+ *val = be32_to_cpu(buf) >> 8;
+ break;
+ }
+ default:
+ return -EINVAL;
+ }
+
+ *val = sign_extend32(*val >> data->shift, chan->scan_type.realbits - 1);
+
+ return 0;
+}
+
+static irqreturn_t ti_adc_trigger_handler(int irq, void *private)
+{
+ struct iio_poll_func *pf = private;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ti_adc_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = ti_adc_read_measurement(data, &indio_dev->channels[0],
+ (int *) &data->buffer);
+ if (!ret)
+ iio_push_to_buffers_with_timestamp(indio_dev,
+ data->buffer,
+ iio_get_time_ns(indio_dev));
+
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static int ti_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct ti_adc_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ ret = ti_adc_read_measurement(data, chan, val);
+ iio_device_release_direct_mode(indio_dev);
+
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ ret = regulator_get_voltage(data->ref);
+ if (ret < 0)
+ return ret;
+
+ *val = ret / 1000;
+ *val2 = chan->scan_type.realbits;
+
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_OFFSET:
+ *val = 1 << (chan->scan_type.realbits - 1);
+ return IIO_VAL_INT;
+ }
+
+ return 0;
+}
+
+static const struct iio_info ti_adc_info = {
+ .read_raw = ti_adc_read_raw,
+};
+
+static void ti_adc_reg_disable(void *reg)
+{
+ regulator_disable(reg);
+}
+
+static int ti_adc_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct ti_adc_data *data;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ indio_dev->info = &ti_adc_info;
+ indio_dev->name = TI_ADC_DRV_NAME;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ data = iio_priv(indio_dev);
+ data->spi = spi;
+
+ switch (spi_get_device_id(spi)->driver_data) {
+ case TI_ADC141S626:
+ indio_dev->channels = ti_adc141s626_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ti_adc141s626_channels);
+ data->shift = 0;
+ data->read_size = 2;
+ break;
+ case TI_ADC161S626:
+ indio_dev->channels = ti_adc161s626_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ti_adc161s626_channels);
+ data->shift = 6;
+ data->read_size = 3;
+ break;
+ }
+
+ data->ref = devm_regulator_get(&spi->dev, "vdda");
+ if (IS_ERR(data->ref))
+ return PTR_ERR(data->ref);
+
+ ret = regulator_enable(data->ref);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_add_action_or_reset(&spi->dev, ti_adc_reg_disable,
+ data->ref);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL,
+ ti_adc_trigger_handler, NULL);
+ if (ret)
+ return ret;
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct of_device_id ti_adc_dt_ids[] = {
+ { .compatible = "ti,adc141s626", },
+ { .compatible = "ti,adc161s626", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ti_adc_dt_ids);
+
+static const struct spi_device_id ti_adc_id[] = {
+ {"adc141s626", TI_ADC141S626},
+ {"adc161s626", TI_ADC161S626},
+ {},
+};
+MODULE_DEVICE_TABLE(spi, ti_adc_id);
+
+static struct spi_driver ti_adc_driver = {
+ .driver = {
+ .name = TI_ADC_DRV_NAME,
+ .of_match_table = ti_adc_dt_ids,
+ },
+ .probe = ti_adc_probe,
+ .id_table = ti_adc_id,
+};
+module_spi_driver(ti_adc_driver);
+
+MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
+MODULE_DESCRIPTION("Texas Instruments ADC1x1S 1-channel differential ADC");
+MODULE_LICENSE("GPL");