File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/iio/temperature/tmp006.c b/drivers/iio/temperature/tmp006.c
new file mode 100644
index 0000000..e78c106
--- /dev/null
+++ b/drivers/iio/temperature/tmp006.c
@@ -0,0 +1,292 @@
+/*
+ * tmp006.c - Support for TI TMP006 IR thermopile sensor
+ *
+ * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
+ *
+ * (7-bit I2C slave address 0x40, changeable via ADR pins)
+ *
+ * TODO: data ready irq
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/bitops.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define TMP006_VOBJECT 0x00
+#define TMP006_TAMBIENT 0x01
+#define TMP006_CONFIG 0x02
+#define TMP006_MANUFACTURER_ID 0xfe
+#define TMP006_DEVICE_ID 0xff
+
+#define TMP006_TAMBIENT_SHIFT 2
+
+#define TMP006_CONFIG_RESET BIT(15)
+#define TMP006_CONFIG_DRDY_EN BIT(8)
+#define TMP006_CONFIG_DRDY BIT(7)
+
+#define TMP006_CONFIG_MOD_MASK GENMASK(14, 12)
+
+#define TMP006_CONFIG_CR_MASK GENMASK(11, 9)
+#define TMP006_CONFIG_CR_SHIFT 9
+
+#define TMP006_MANUFACTURER_MAGIC 0x5449
+#define TMP006_DEVICE_MAGIC 0x0067
+
+struct tmp006_data {
+	struct i2c_client *client;
+	u16 config;
+};
+
+static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
+{
+	s32 ret;
+	int tries = 50;
+
+	while (tries-- > 0) {
+		ret = i2c_smbus_read_word_swapped(data->client,
+			TMP006_CONFIG);
+		if (ret < 0)
+			return ret;
+		if (ret & TMP006_CONFIG_DRDY)
+			break;
+		msleep(100);
+	}
+
+	if (tries < 0)
+		return -EIO;
+
+	return i2c_smbus_read_word_swapped(data->client, reg);
+}
+
+static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
+					{0, 500000}, {0, 250000} };
+
+static int tmp006_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *channel, int *val,
+			    int *val2, long mask)
+{
+	struct tmp006_data *data = iio_priv(indio_dev);
+	s32 ret;
+	int cr;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (channel->type == IIO_VOLTAGE) {
+			/* LSB is 156.25 nV */
+			ret = tmp006_read_measurement(data, TMP006_VOBJECT);
+			if (ret < 0)
+				return ret;
+			*val = sign_extend32(ret, 15);
+		} else if (channel->type == IIO_TEMP) {
+			/* LSB is 0.03125 degrees Celsius */
+			ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
+			if (ret < 0)
+				return ret;
+			*val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
+		} else {
+			break;
+		}
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		if (channel->type == IIO_VOLTAGE) {
+			*val = 0;
+			*val2 = 156250;
+		} else if (channel->type == IIO_TEMP) {
+			*val = 31;
+			*val2 = 250000;
+		} else {
+			break;
+		}
+		return IIO_VAL_INT_PLUS_MICRO;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		cr = (data->config & TMP006_CONFIG_CR_MASK)
+			>> TMP006_CONFIG_CR_SHIFT;
+		*val = tmp006_freqs[cr][0];
+		*val2 = tmp006_freqs[cr][1];
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int tmp006_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long mask)
+{
+	struct tmp006_data *data = iio_priv(indio_dev);
+	int i;
+
+	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
+		return -EINVAL;
+
+	for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
+		if ((val == tmp006_freqs[i][0]) &&
+		    (val2 == tmp006_freqs[i][1])) {
+			data->config &= ~TMP006_CONFIG_CR_MASK;
+			data->config |= i << TMP006_CONFIG_CR_SHIFT;
+
+			return i2c_smbus_write_word_swapped(data->client,
+							    TMP006_CONFIG,
+							    data->config);
+
+		}
+	return -EINVAL;
+}
+
+static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
+
+static struct attribute *tmp006_attributes[] = {
+	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group tmp006_attribute_group = {
+	.attrs = tmp006_attributes,
+};
+
+static const struct iio_chan_spec tmp006_channels[] = {
+	{
+		.type = IIO_VOLTAGE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+			BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+	},
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+			BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+	}
+};
+
+static const struct iio_info tmp006_info = {
+	.read_raw = tmp006_read_raw,
+	.write_raw = tmp006_write_raw,
+	.attrs = &tmp006_attribute_group,
+	.driver_module = THIS_MODULE,
+};
+
+static bool tmp006_check_identification(struct i2c_client *client)
+{
+	int mid, did;
+
+	mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
+	if (mid < 0)
+		return false;
+
+	did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
+	if (did < 0)
+		return false;
+
+	return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC;
+}
+
+static int tmp006_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct tmp006_data *data;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
+		return -ENODEV;
+
+	if (!tmp006_check_identification(client)) {
+		dev_err(&client->dev, "no TMP006 sensor\n");
+		return -ENODEV;
+	}
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->name = dev_name(&client->dev);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &tmp006_info;
+
+	indio_dev->channels = tmp006_channels;
+	indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
+
+	ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
+	if (ret < 0)
+		return ret;
+	data->config = ret;
+
+	return iio_device_register(indio_dev);
+}
+
+static int tmp006_powerdown(struct tmp006_data *data)
+{
+	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
+		data->config & ~TMP006_CONFIG_MOD_MASK);
+}
+
+static int tmp006_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+	tmp006_powerdown(iio_priv(indio_dev));
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tmp006_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	return tmp006_powerdown(iio_priv(indio_dev));
+}
+
+static int tmp006_resume(struct device *dev)
+{
+	struct tmp006_data *data = iio_priv(i2c_get_clientdata(
+		to_i2c_client(dev)));
+	return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
+		data->config | TMP006_CONFIG_MOD_MASK);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);
+
+static const struct i2c_device_id tmp006_id[] = {
+	{ "tmp006", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tmp006_id);
+
+static struct i2c_driver tmp006_driver = {
+	.driver = {
+		.name	= "tmp006",
+		.pm	= &tmp006_pm_ops,
+	},
+	.probe = tmp006_probe,
+	.remove = tmp006_remove,
+	.id_table = tmp006_id,
+};
+module_i2c_driver(tmp006_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
+MODULE_LICENSE("GPL");