Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 277 insertions, 0 deletions

diff --git a/drivers/iio/adc/ti-adc081c.c b/drivers/iio/adc/ti-adc081c.c
new file mode 100644
index 000000000..ef95363eb
--- /dev/null
+++ b/drivers/iio/adc/ti-adc081c.c
@@ -0,0 +1,277 @@
+/*
+ * TI ADC081C/ADC101C/ADC121C 8/10/12-bit ADC driver
+ *
+ * Copyright (C) 2012 Avionic Design GmbH
+ * Copyright (C) 2016 Intel
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Datasheets:
+ *	http://www.ti.com/lit/ds/symlink/adc081c021.pdf
+ *	http://www.ti.com/lit/ds/symlink/adc101c021.pdf
+ *	http://www.ti.com/lit/ds/symlink/adc121c021.pdf
+ *
+ * The devices have a very similar interface and differ mostly in the number of
+ * bits handled. For the 8-bit and 10-bit models the least-significant 4 or 2
+ * bits of value registers are reserved.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/acpi.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/regulator/consumer.h>
+
+struct adc081c {
+	struct i2c_client *i2c;
+	struct regulator *ref;
+
+	/* 8, 10 or 12 */
+	int bits;
+
+	/* Ensure natural alignment of buffer elements */
+	struct {
+		u16 channel;
+		s64 ts __aligned(8);
+	} scan;
+};
+
+#define REG_CONV_RES 0x00
+
+static int adc081c_read_raw(struct iio_dev *iio,
+			    struct iio_chan_spec const *channel, int *value,
+			    int *shift, long mask)
+{
+	struct adc081c *adc = iio_priv(iio);
+	int err;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES);
+		if (err < 0)
+			return err;
+
+		*value = (err & 0xFFF) >> (12 - adc->bits);
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		err = regulator_get_voltage(adc->ref);
+		if (err < 0)
+			return err;
+
+		*value = err / 1000;
+		*shift = adc->bits;
+
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+#define ADCxx1C_CHAN(_bits) {					\
+	.type = IIO_VOLTAGE,					\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.scan_type = {						\
+		.sign = 'u',					\
+		.realbits = (_bits),				\
+		.storagebits = 16,				\
+		.shift = 12 - (_bits),				\
+		.endianness = IIO_CPU,				\
+	},							\
+}
+
+#define DEFINE_ADCxx1C_CHANNELS(_name, _bits)				\
+	static const struct iio_chan_spec _name ## _channels[] = {	\
+		ADCxx1C_CHAN((_bits)),					\
+		IIO_CHAN_SOFT_TIMESTAMP(1),				\
+	};								\
+
+#define ADC081C_NUM_CHANNELS 2
+
+struct adcxx1c_model {
+	const struct iio_chan_spec* channels;
+	int bits;
+};
+
+#define ADCxx1C_MODEL(_name, _bits)					\
+	{								\
+		.channels = _name ## _channels,				\
+		.bits = (_bits),					\
+	}
+
+DEFINE_ADCxx1C_CHANNELS(adc081c,  8);
+DEFINE_ADCxx1C_CHANNELS(adc101c, 10);
+DEFINE_ADCxx1C_CHANNELS(adc121c, 12);
+
+/* Model ids are indexes in _models array */
+enum adcxx1c_model_id {
+	ADC081C = 0,
+	ADC101C = 1,
+	ADC121C = 2,
+};
+
+static struct adcxx1c_model adcxx1c_models[] = {
+	ADCxx1C_MODEL(adc081c,  8),
+	ADCxx1C_MODEL(adc101c, 10),
+	ADCxx1C_MODEL(adc121c, 12),
+};
+
+static const struct iio_info adc081c_info = {
+	.read_raw = adc081c_read_raw,
+};
+
+static irqreturn_t adc081c_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct adc081c *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES);
+	if (ret < 0)
+		goto out;
+	data->scan.channel = ret;
+	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
+					   iio_get_time_ns(indio_dev));
+out:
+	iio_trigger_notify_done(indio_dev->trig);
+	return IRQ_HANDLED;
+}
+
+static int adc081c_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct iio_dev *iio;
+	struct adc081c *adc;
+	struct adcxx1c_model *model;
+	int err;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
+		return -EOPNOTSUPP;
+
+	if (ACPI_COMPANION(&client->dev)) {
+		const struct acpi_device_id *ad_id;
+
+		ad_id = acpi_match_device(client->dev.driver->acpi_match_table,
+					  &client->dev);
+		if (!ad_id)
+			return -ENODEV;
+		model = &adcxx1c_models[ad_id->driver_data];
+	} else {
+		model = &adcxx1c_models[id->driver_data];
+	}
+
+	iio = devm_iio_device_alloc(&client->dev, sizeof(*adc));
+	if (!iio)
+		return -ENOMEM;
+
+	adc = iio_priv(iio);
+	adc->i2c = client;
+	adc->bits = model->bits;
+
+	adc->ref = devm_regulator_get(&client->dev, "vref");
+	if (IS_ERR(adc->ref))
+		return PTR_ERR(adc->ref);
+
+	err = regulator_enable(adc->ref);
+	if (err < 0)
+		return err;
+
+	iio->dev.parent = &client->dev;
+	iio->dev.of_node = client->dev.of_node;
+	iio->name = dev_name(&client->dev);
+	iio->modes = INDIO_DIRECT_MODE;
+	iio->info = &adc081c_info;
+
+	iio->channels = model->channels;
+	iio->num_channels = ADC081C_NUM_CHANNELS;
+
+	err = iio_triggered_buffer_setup(iio, NULL, adc081c_trigger_handler, NULL);
+	if (err < 0) {
+		dev_err(&client->dev, "iio triggered buffer setup failed\n");
+		goto err_regulator_disable;
+	}
+
+	err = iio_device_register(iio);
+	if (err < 0)
+		goto err_buffer_cleanup;
+
+	i2c_set_clientdata(client, iio);
+
+	return 0;
+
+err_buffer_cleanup:
+	iio_triggered_buffer_cleanup(iio);
+err_regulator_disable:
+	regulator_disable(adc->ref);
+
+	return err;
+}
+
+static int adc081c_remove(struct i2c_client *client)
+{
+	struct iio_dev *iio = i2c_get_clientdata(client);
+	struct adc081c *adc = iio_priv(iio);
+
+	iio_device_unregister(iio);
+	iio_triggered_buffer_cleanup(iio);
+	regulator_disable(adc->ref);
+
+	return 0;
+}
+
+static const struct i2c_device_id adc081c_id[] = {
+	{ "adc081c", ADC081C },
+	{ "adc101c", ADC101C },
+	{ "adc121c", ADC121C },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, adc081c_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id adc081c_of_match[] = {
+	{ .compatible = "ti,adc081c" },
+	{ .compatible = "ti,adc101c" },
+	{ .compatible = "ti,adc121c" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, adc081c_of_match);
+#endif
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id adc081c_acpi_match[] = {
+	{ "ADC081C", ADC081C },
+	{ "ADC101C", ADC101C },
+	{ "ADC121C", ADC121C },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, adc081c_acpi_match);
+#endif
+
+static struct i2c_driver adc081c_driver = {
+	.driver = {
+		.name = "adc081c",
+		.of_match_table = of_match_ptr(adc081c_of_match),
+		.acpi_match_table = ACPI_PTR(adc081c_acpi_match),
+	},
+	.probe = adc081c_probe,
+	.remove = adc081c_remove,
+	.id_table = adc081c_id,
+};
+module_i2c_driver(adc081c_driver);
+
+MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
+MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver");
+MODULE_LICENSE("GPL v2");