Merge tag 'iio-for-4.12c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Third set of new device support, cleanups and features for IIO in the 4.12 cycle

Somewhat dominated in patch numbers of last of the outreachy application
window related patches (they are still coming, despite window being closed
which is good to see!)

Good set of new drivers as well.

New device support
* ASPEED ADC
  - new driver
* cpcap PMIC ADC
  - new driver
* hid-humidity
  - driver for HID compatible humidity sensors.
* ltc2497 ADC
  - new driver
* mpu6050
  - bring bindings up to date and add trivial support for 9250
* rockchip-saradc
  - update bindings to cover rk3328
* vl6180 light, proximity and time of flight sensor.
  - new driver

Features
* meson-saradc
  - add calibration

Cleanup and minor fixes
* ad5504
  - constify attribute_group structure
  - drop casting of void *
* ad7150
  - replace some shifts of 1 by BIT macro usage
* ad7152
  - blank lines between function definitions
* ad7280a
  - octal permissions.
* ad7606
  - replace use of core mlock mutex with a local lock
* ad7746
  - replace some shifts of 1 by BIT macro usage
  - function parameter alignment
  - drop some excessive brackets (introduced in last pull request)
* ad7753
  - white space cleanup
* ad7754
  - includes in alphabetical order and groupped appropriately.
  - change from missuse of internal mlock mutex to using the buffer lock to
  also protect values during frequency update.
* ad779x
  - constify attribute_group structures
* ad9832
  - octal permissions
* adis16060
  - remove use of core mlock mutex in favour of adding a local
  _spi_write_then_read which can use the local buffer protection lock.
  - fix naming of above function.
* adis16203
  - remove locking during reads of calibbias that doesn't protect anything
  not protected elsewhere.
* adis16209
  - remove unnecessary braces in single statement if
* adis16240
  - remove unnecessary braces in single statement if
* adt7136
  - drop excess blank lines and put some in between functions.
* ams-iaq
  - replace comma with semi colon. Not actual bug, just unusual syntax.
* apds9960
  - constify attribute group structure
* as3935
  - constify attribute group structure
* bm1750
  - constify attribute group structure
* cros_ec
  - devm version of triggered buffer setup to simplify code.
* exynos
  - drop casting of void *
* hdc100x
  - constify attribute_group structure
* hid-accel
  - fix wrong scale for newly introduced gravity sensor.
* hts221
  - drop casting of void *
* hx711
  - constify attribute_group structure
* imx7d_adc
  - drop casting of void *
* lm35333
  - constify attribute_group structure
* lsm6dsx
  - drop casting of void *
  - hold ODR configuration until enabling to avoid a race condition.
* max1027
  - drop casting of void *
* max11100
  - fix a comma where semicolon was intended (no actual bug, just odd)
* max1363
  - constify attribute_group structure
* ms sensors
  - drop casting of void *
* rockchip_saradc
  - drop casting of void *
* sun4i-gpadc
  - fix missing dependency on THERMAL or presence of stubs (issue only
  introduced in pervious set)
  - drop casting of void *
* tsl2x7x
  - fix wrong standard deviation calc.  Note these aren't actually used for
  anything at the moment so bug didn't really matter.
  - constify attribute group structure.
* vf610adc
  - drop casting of void *
* vz89x
  - replace comma with semicolon. Not actual bug, just odd syntax.
* zpa2326
  - drop casting of void *

1 files changed, 279 insertions, 0 deletions

diff --git a/drivers/iio/adc/ltc2497.c b/drivers/iio/adc/ltc2497.c
new file mode 100644
index 000000000000..2691b10023f5
--- /dev/null
+++ b/drivers/iio/adc/ltc2497.c
@@ -0,0 +1,279 @@
+/*
+ * ltc2497.c - Driver for Analog Devices/Linear Technology LTC2497 ADC
+ *
+ * Copyright (C) 2017 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ *
+ * Datasheet: http://cds.linear.com/docs/en/datasheet/2497fd.pdf
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+
+#define LTC2497_ENABLE			0xA0
+#define LTC2497_SGL			BIT(4)
+#define LTC2497_DIFF			0
+#define LTC2497_SIGN			BIT(3)
+#define LTC2497_CONFIG_DEFAULT		LTC2497_ENABLE
+#define LTC2497_CONVERSION_TIME_MS	150ULL
+
+struct ltc2497_st {
+	struct i2c_client *client;
+	struct regulator *ref;
+	ktime_t	time_prev;
+	u8 addr_prev;
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+	__be32 buf ____cacheline_aligned;
+};
+
+static int ltc2497_wait_conv(struct ltc2497_st *st)
+{
+	s64 time_elapsed;
+
+	time_elapsed = ktime_ms_delta(ktime_get(), st->time_prev);
+
+	if (time_elapsed < LTC2497_CONVERSION_TIME_MS) {
+		/* delay if conversion time not passed
+		 * since last read or write
+		 */
+		if (msleep_interruptible(
+		    LTC2497_CONVERSION_TIME_MS - time_elapsed))
+			return -ERESTARTSYS;
+
+		return 0;
+	}
+
+	if (time_elapsed - LTC2497_CONVERSION_TIME_MS <= 0) {
+		/* We're in automatic mode -
+		 * so the last reading is stil not outdated
+		 */
+		return 0;
+	}
+
+	return 1;
+}
+
+static int ltc2497_read(struct ltc2497_st *st, u8 address, int *val)
+{
+	struct i2c_client *client = st->client;
+	int ret;
+
+	ret = ltc2497_wait_conv(st);
+	if (ret < 0)
+		return ret;
+
+	if (ret || st->addr_prev != address) {
+		ret = i2c_smbus_write_byte(st->client,
+					   LTC2497_ENABLE | address);
+		if (ret < 0)
+			return ret;
+		st->addr_prev = address;
+		if (msleep_interruptible(LTC2497_CONVERSION_TIME_MS))
+			return -ERESTARTSYS;
+	}
+	ret = i2c_master_recv(client, (char *)&st->buf, 3);
+	if (ret < 0)  {
+		dev_err(&client->dev, "i2c_master_recv failed\n");
+		return ret;
+	}
+	st->time_prev = ktime_get();
+
+	/* convert and shift the result,
+	 * and finally convert from offset binary to signed integer
+	 */
+	*val = (be32_to_cpu(st->buf) >> 14) - (1 << 17);
+
+	return ret;
+}
+
+static int ltc2497_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct ltc2497_st *st = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&indio_dev->mlock);
+		ret = ltc2497_read(st, chan->address, val);
+		mutex_unlock(&indio_dev->mlock);
+		if (ret < 0)
+			return ret;
+
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		ret = regulator_get_voltage(st->ref);
+		if (ret < 0)
+			return ret;
+
+		*val = ret / 1000;
+		*val2 = 17;
+
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+#define LTC2497_CHAN(_chan, _addr) { \
+	.type = IIO_VOLTAGE, \
+	.indexed = 1, \
+	.channel = (_chan), \
+	.address = (_addr | (_chan / 2) | ((_chan & 1) ? LTC2497_SIGN : 0)), \
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+}
+
+#define LTC2497_CHAN_DIFF(_chan, _addr) { \
+	.type = IIO_VOLTAGE, \
+	.indexed = 1, \
+	.channel = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 1 : 0), \
+	.channel2 = (_chan) * 2 + ((_addr) & LTC2497_SIGN ? 0 : 1),\
+	.address = (_addr | _chan), \
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+	.differential = 1, \
+}
+
+static const struct iio_chan_spec ltc2497_channel[] = {
+	LTC2497_CHAN(0, LTC2497_SGL),
+	LTC2497_CHAN(1, LTC2497_SGL),
+	LTC2497_CHAN(2, LTC2497_SGL),
+	LTC2497_CHAN(3, LTC2497_SGL),
+	LTC2497_CHAN(4, LTC2497_SGL),
+	LTC2497_CHAN(5, LTC2497_SGL),
+	LTC2497_CHAN(6, LTC2497_SGL),
+	LTC2497_CHAN(7, LTC2497_SGL),
+	LTC2497_CHAN(8, LTC2497_SGL),
+	LTC2497_CHAN(9, LTC2497_SGL),
+	LTC2497_CHAN(10, LTC2497_SGL),
+	LTC2497_CHAN(11, LTC2497_SGL),
+	LTC2497_CHAN(12, LTC2497_SGL),
+	LTC2497_CHAN(13, LTC2497_SGL),
+	LTC2497_CHAN(14, LTC2497_SGL),
+	LTC2497_CHAN(15, LTC2497_SGL),
+	LTC2497_CHAN_DIFF(0, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(1, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(2, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(3, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(4, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(5, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(6, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(7, LTC2497_DIFF),
+	LTC2497_CHAN_DIFF(0, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(1, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(2, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(3, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(4, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(5, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(6, LTC2497_DIFF | LTC2497_SIGN),
+	LTC2497_CHAN_DIFF(7, LTC2497_DIFF | LTC2497_SIGN),
+};
+
+static const struct iio_info ltc2497_info = {
+	.read_raw = ltc2497_read_raw,
+	.driver_module = THIS_MODULE,
+};
+
+static int ltc2497_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct iio_dev *indio_dev;
+	struct ltc2497_st *st;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
+				     I2C_FUNC_SMBUS_WRITE_BYTE))
+		return -EOPNOTSUPP;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	st->client = client;
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->name = id->name;
+	indio_dev->info = &ltc2497_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = ltc2497_channel;
+	indio_dev->num_channels = ARRAY_SIZE(ltc2497_channel);
+
+	st->ref = devm_regulator_get(&client->dev, "vref");
+	if (IS_ERR(st->ref))
+		return PTR_ERR(st->ref);
+
+	ret = regulator_enable(st->ref);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_write_byte(st->client, LTC2497_CONFIG_DEFAULT);
+	if (ret < 0)
+		goto err_regulator_disable;
+
+	st->addr_prev = LTC2497_CONFIG_DEFAULT;
+	st->time_prev = ktime_get();
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0)
+		goto err_regulator_disable;
+
+	return 0;
+
+err_regulator_disable:
+	regulator_disable(st->ref);
+
+	return ret;
+}
+
+static int ltc2497_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct ltc2497_st *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	regulator_disable(st->ref);
+
+	return 0;
+}
+
+static const struct i2c_device_id ltc2497_id[] = {
+	{ "ltc2497", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ltc2497_id);
+
+static const struct of_device_id ltc2497_of_match[] = {
+	{ .compatible = "lltc,ltc2497", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ltc2497_of_match);
+
+static struct i2c_driver ltc2497_driver = {
+	.driver = {
+		.name = "ltc2497",
+		.of_match_table = of_match_ptr(ltc2497_of_match),
+	},
+	.probe = ltc2497_probe,
+	.remove = ltc2497_remove,
+	.id_table = ltc2497_id,
+};
+module_i2c_driver(ltc2497_driver);
+
+MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
+MODULE_DESCRIPTION("Linear Technology LTC2497 ADC driver");
+MODULE_LICENSE("GPL v2");