Merge tag 'iio-for-4.8a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First round of IIO new device support, features and cleanups for the 4.8 cycle.

New device support
* ads1015
  - add ads1115 support
* bma220 accelerometer
  - new driver
  - triggered buffer support.
* bmc150
  - add bmm150 support.
* bmp280
  - bme280 support with addition of humidity channel.
* max5487 potentiometer
  - new driver
* MMA7660FC accelerometer.
  - New driver
* st-pressure
  - support for the lps22hb
* loop trigger.
  - This one is *nasty* but we have real applications (parrot drones) where
  it is useful.  The trigger basically spins as hard as it can firing off
  a new trigger each time all triggered devices come back to say they are
  done.  It doesn't hang a machine even when doing it on a dummy driver.
  A lot nicer than having this implemented within lots of device drivers
  anyway.

Core stuff
* Add support to create IIO devices via configfs (similar to we did for
triggers a while back) + docs.
* New channel types
  - IIO_ELECTRICAL_CONDUCTIVITY
* Couple of MAINTAINERS patches to list the device tree bindings.
* Make trigger ops structure non optional (comment fix). It hasn't been for
an awful long time, but that's not what the description said.

New features
* ak8975
  - support adapters that are limited to byte data only by allowing the
  emulated block read i2c function that was recently introduced.
* atlas-ph
  - support atlas-ec (electrical conductivity sensor)
* bmi160
  - add available frequency and scale attributes to make the driver
  more user friendly (and avoid having to read the datasheet to know
  what will work).
* dummy
  - move creation to configfs interface.  It's not real hardware so we
  are not that worried about the ABI breakage ;)
* mma8452
  - oversampling ration support
* nau7802
  - expose available gains to make life easier for userspace.
* st-sensors
  - allow use of emulation for SMBus block reads as all the st parts support
  it.
* ti-ads1015
  - list datasheet names to allow their use by inkernel consumers.
* Various module alias additions to help auto probing.  Drop one redundant one
as well.

Cleanups
* ad7266, ad7476, ad7887, ad7923, ad799x
  - use direct mode claim function rather than open coding it during sensor
  read (prevents switching on buffers mid read).
* ad7793, ad7791
  - use direct mode claim to prevent frequency changes when buffers running.
* afe440x - These are ABI breaking but the driver requires custom userspace
  code to do anything useful anyway and that is still being written and under
  control of TI.  Ultimately we may have other libraries to do pulse
  oximetry with these devices but we aren't aware of any yet.
  - kernel-doc format fixes
  - drop ifdef fun around of_match_ptr - it's not worth the mess to save
  a tiny amount of space.
  - drop some unnecessary register initializations.
  - drop the weird locked gain modes as they gain us nothing (can just set
  all gains separately).
  - remove handling of offset attributes seeing as no channels actually have
  them (oops)
  - Drop the LED3 input channel as it's an alias for ALED2.
  - *big one* remove channel names - an experiment that turned out to not
  make sense - see patch for details.
  - use regmap fields to clean up code.
  - tie the tia gain stages to appropriate channels in the ABI as that is
  what they really effect. Same with the LED currents.
  - cleanout some unused defines and fix a missnamed one.
* atlas-ph
  - reorganise to allow support of other similar parts.
* bmc150
  - document supported chips in kconfig help.
* jsa1212
  - drop an unneeded i2c functionality check for functionality the driver
  doesn't use.
* mxs-lradc
  - simply touch screen registration code.
  - remove the touch screen unregister as all devm based now.
  - disable only those channels that are masked in hardware stop (others
  are already dealt with elsewhere)
* st-sensors
  - unexport st_sensors_get_buffer_element as nothing outside the st-sensors
  core driver uses it.
  - fix handling of failure to start up regulators.
* tpl0102
  - drop an i2c functionality test for features that aren't needed.
* ti-am335x
  - use variable name rather than type in sizeof for clarity.
  - use SIMPLE_DEV_PM_OPS helper macro to tidy up a bit.

Tools
* Add install / uninstall to makefile.  Someone cares, so presumably
some people will find it useful!
*  generic_buffer
   - rename to iio_generic_buffer to line up with other tools.
   - handle cleanup when receiving signals
   - Add a --device-num option and a --trigger-num option rather than
   relying on naming which doesn't work if you have two of the same part.

1 files changed, 198 insertions, 2 deletions

diff --git a/drivers/iio/pressure/bmp280.c b/drivers/iio/pressure/bmp280.c
index 2f1498e..1876b50 100644
--- a/drivers/iio/pressure/bmp280.c
+++ b/drivers/iio/pressure/bmp280.c
@@ -10,6 +10,7 @@
  * Datasheet:
  * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf
  * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf
+ * https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf
  */
 
 #define pr_fmt(fmt) "bmp280: " fmt
@@ -23,6 +24,8 @@
 #include <linux/iio/sysfs.h>
 
 /* BMP280 specific registers */
+#define BMP280_REG_HUMIDITY_LSB		0xFE
+#define BMP280_REG_HUMIDITY_MSB		0xFD
 #define BMP280_REG_TEMP_XLSB		0xFC
 #define BMP280_REG_TEMP_LSB		0xFB
 #define BMP280_REG_TEMP_MSB		0xFA
@@ -31,7 +34,17 @@
 #define BMP280_REG_PRESS_MSB		0xF7
 
 #define BMP280_REG_CONFIG		0xF5
+#define BMP280_REG_CTRL_MEAS		0xF4
 #define BMP280_REG_STATUS		0xF3
+#define BMP280_REG_CTRL_HUMIDITY	0xF2
+
+/* Due to non linear mapping, and data sizes we can't do a bulk read */
+#define BMP280_REG_COMP_H1		0xA1
+#define BMP280_REG_COMP_H2		0xE1
+#define BMP280_REG_COMP_H3		0xE3
+#define BMP280_REG_COMP_H4		0xE4
+#define BMP280_REG_COMP_H5		0xE5
+#define BMP280_REG_COMP_H6		0xE7
 
 #define BMP280_REG_COMP_TEMP_START	0x88
 #define BMP280_COMP_TEMP_REG_COUNT	6
@@ -46,6 +59,15 @@
 #define BMP280_FILTER_8X		(BIT(3) | BIT(2))
 #define BMP280_FILTER_16X		BIT(4)
 
+#define BMP280_OSRS_HUMIDITY_MASK	(BIT(2) | BIT(1) | BIT(0))
+#define BMP280_OSRS_HUMIDITIY_X(osrs_h)	((osrs_h) << 0)
+#define BMP280_OSRS_HUMIDITY_SKIP	0
+#define BMP280_OSRS_HUMIDITY_1X		BMP280_OSRS_HUMIDITIY_X(1)
+#define BMP280_OSRS_HUMIDITY_2X		BMP280_OSRS_HUMIDITIY_X(2)
+#define BMP280_OSRS_HUMIDITY_4X		BMP280_OSRS_HUMIDITIY_X(3)
+#define BMP280_OSRS_HUMIDITY_8X		BMP280_OSRS_HUMIDITIY_X(4)
+#define BMP280_OSRS_HUMIDITY_16X	BMP280_OSRS_HUMIDITIY_X(5)
+
 #define BMP280_OSRS_TEMP_MASK		(BIT(7) | BIT(6) | BIT(5))
 #define BMP280_OSRS_TEMP_SKIP		0
 #define BMP280_OSRS_TEMP_X(osrs_t)	((osrs_t) << 5)
@@ -92,6 +114,7 @@
 
 #define BMP180_CHIP_ID			0x55
 #define BMP280_CHIP_ID			0x58
+#define BME280_CHIP_ID			0x60
 #define BMP280_SOFT_RESET_VAL		0xB6
 
 struct bmp280_data {
@@ -103,6 +126,7 @@ struct bmp280_data {
 	/* log of base 2 of oversampling rate */
 	u8 oversampling_press;
 	u8 oversampling_temp;
+	u8 oversampling_humid;
 
 	/*
 	 * Carryover value from temperature conversion, used in pressure
@@ -120,9 +144,13 @@ struct bmp280_chip_info {
 	const int *oversampling_press_avail;
 	int num_oversampling_press_avail;
 
+	const int *oversampling_humid_avail;
+	int num_oversampling_humid_avail;
+
 	int (*chip_config)(struct bmp280_data *);
 	int (*read_temp)(struct bmp280_data *, int *);
 	int (*read_press)(struct bmp280_data *, int *, int *);
+	int (*read_humid)(struct bmp280_data *, int *, int *);
 };
 
 /*
@@ -143,12 +171,18 @@ static const struct iio_chan_spec bmp280_channels[] = {
 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
 				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
 	},
+	{
+		.type = IIO_HUMIDITYRELATIVE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+	},
 };
 
 static bool bmp280_is_writeable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case BMP280_REG_CONFIG:
+	case BMP280_REG_CTRL_HUMIDITY:
 	case BMP280_REG_CTRL_MEAS:
 	case BMP280_REG_RESET:
 		return true;
@@ -160,6 +194,8 @@ static bool bmp280_is_writeable_reg(struct device *dev, unsigned int reg)
 static bool bmp280_is_volatile_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
+	case BMP280_REG_HUMIDITY_LSB:
+	case BMP280_REG_HUMIDITY_MSB:
 	case BMP280_REG_TEMP_XLSB:
 	case BMP280_REG_TEMP_LSB:
 	case BMP280_REG_TEMP_MSB:
@@ -177,7 +213,7 @@ static const struct regmap_config bmp280_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 
-	.max_register = BMP280_REG_TEMP_XLSB,
+	.max_register = BMP280_REG_HUMIDITY_LSB,
 	.cache_type = REGCACHE_RBTREE,
 
 	.writeable_reg = bmp280_is_writeable_reg,
@@ -185,6 +221,70 @@ static const struct regmap_config bmp280_regmap_config = {
 };
 
 /*
+ * Returns humidity in percent, resolution is 0.01 percent. Output value of
+ * "47445" represents 47445/1024 = 46.333 %RH.
+ *
+ * Taken from BME280 datasheet, Section 4.2.3, "Compensation formula".
+ */
+
+static u32 bmp280_compensate_humidity(struct bmp280_data *data,
+				      s32 adc_humidity)
+{
+	struct device *dev = &data->client->dev;
+	unsigned int H1, H3, tmp;
+	int H2, H4, H5, H6, ret, var;
+
+	ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &H1);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H1 comp value\n");
+		return ret;
+	}
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H2 comp value\n");
+		return ret;
+	}
+	H2 = sign_extend32(le16_to_cpu(tmp), 15);
+
+	ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &H3);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H3 comp value\n");
+		return ret;
+	}
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H4 comp value\n");
+		return ret;
+	}
+	H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) |
+			  (be16_to_cpu(tmp) & 0xf), 11);
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H5 comp value\n");
+		return ret;
+	}
+	H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 11);
+
+	ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
+	if (ret < 0) {
+		dev_err(dev, "failed to read H6 comp value\n");
+		return ret;
+	}
+	H6 = sign_extend32(tmp, 7);
+
+	var = ((s32)data->t_fine) - 76800;
+	var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var)) + 16384) >> 15)
+		* (((((((var * H6) >> 10) * (((var * H3) >> 11) + 32768)) >> 10)
+		+ 2097152) * H2 + 8192) >> 14);
+	var -= ((((var >> 15) * (var >> 15)) >> 7) * H1) >> 4;
+
+	return var >> 12;
+};
+
+/*
  * Returns temperature in DegC, resolution is 0.01 DegC.  Output value of
  * "5123" equals 51.23 DegC.  t_fine carries fine temperature as global
  * value.
@@ -324,6 +424,34 @@ static int bmp280_read_press(struct bmp280_data *data,
 	return IIO_VAL_FRACTIONAL;
 }
 
+static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
+{
+	int ret;
+	__be16 tmp = 0;
+	s32 adc_humidity;
+	u32 comp_humidity;
+
+	/* Read and compensate temperature so we get a reading of t_fine. */
+	ret = bmp280_read_temp(data, NULL);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
+			       (u8 *) &tmp, 2);
+	if (ret < 0) {
+		dev_err(&data->client->dev, "failed to read humidity\n");
+		return ret;
+	}
+
+	adc_humidity = be16_to_cpu(tmp);
+	comp_humidity = bmp280_compensate_humidity(data, adc_humidity);
+
+	*val = comp_humidity;
+	*val2 = 1024;
+
+	return IIO_VAL_FRACTIONAL;
+}
+
 static int bmp280_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val, int *val2, long mask)
@@ -336,6 +464,9 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
 	switch (mask) {
 	case IIO_CHAN_INFO_PROCESSED:
 		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			ret = data->chip_info->read_humid(data, val, val2);
+			break;
 		case IIO_PRESSURE:
 			ret = data->chip_info->read_press(data, val, val2);
 			break;
@@ -349,6 +480,10 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
 		break;
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			*val = 1 << data->oversampling_humid;
+			ret = IIO_VAL_INT;
+			break;
 		case IIO_PRESSURE:
 			*val = 1 << data->oversampling_press;
 			ret = IIO_VAL_INT;
@@ -372,6 +507,23 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
 	return ret;
 }
 
+static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
+					       int val)
+{
+	int i;
+	const int *avail = data->chip_info->oversampling_humid_avail;
+	const int n = data->chip_info->num_oversampling_humid_avail;
+
+	for (i = 0; i < n; i++) {
+		if (avail[i] == val) {
+			data->oversampling_humid = ilog2(val);
+
+			return data->chip_info->chip_config(data);
+		}
+	}
+	return -EINVAL;
+}
+
 static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
 					       int val)
 {
@@ -417,6 +569,9 @@ static int bmp280_write_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 		mutex_lock(&data->lock);
 		switch (chan->type) {
+		case IIO_HUMIDITYRELATIVE:
+			ret = bmp280_write_oversampling_ratio_humid(data, val);
+			break;
 		case IIO_PRESSURE:
 			ret = bmp280_write_oversampling_ratio_press(data, val);
 			break;
@@ -535,6 +690,37 @@ static const struct bmp280_chip_info bmp280_chip_info = {
 	.read_press = bmp280_read_press,
 };
 
+static int bme280_chip_config(struct bmp280_data *data)
+{
+	int ret = bmp280_chip_config(data);
+	u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
+
+	if (ret < 0)
+		return ret;
+
+	return regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY,
+				  BMP280_OSRS_HUMIDITY_MASK, osrs);
+}
+
+static const struct bmp280_chip_info bme280_chip_info = {
+	.regmap_config = &bmp280_regmap_config,
+
+	.oversampling_temp_avail = bmp280_oversampling_avail,
+	.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.oversampling_press_avail = bmp280_oversampling_avail,
+	.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.oversampling_humid_avail = bmp280_oversampling_avail,
+	.num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
+
+	.chip_config = bme280_chip_config,
+	.read_temp = bmp280_read_temp,
+	.read_press = bmp280_read_press,
+	.read_humid = bmp280_read_humid,
+};
+
+
 static bool bmp180_is_writeable_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
@@ -849,21 +1035,29 @@ static int bmp280_probe(struct i2c_client *client,
 	indio_dev->dev.parent = &client->dev;
 	indio_dev->name = id->name;
 	indio_dev->channels = bmp280_channels;
-	indio_dev->num_channels = ARRAY_SIZE(bmp280_channels);
 	indio_dev->info = &bmp280_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
 	switch (id->driver_data) {
 	case BMP180_CHIP_ID:
+		indio_dev->num_channels = 2;
 		data->chip_info = &bmp180_chip_info;
 		data->oversampling_press = ilog2(8);
 		data->oversampling_temp = ilog2(1);
 		break;
 	case BMP280_CHIP_ID:
+		indio_dev->num_channels = 2;
 		data->chip_info = &bmp280_chip_info;
 		data->oversampling_press = ilog2(16);
 		data->oversampling_temp = ilog2(2);
 		break;
+	case BME280_CHIP_ID:
+		indio_dev->num_channels = 3;
+		data->chip_info = &bme280_chip_info;
+		data->oversampling_press = ilog2(16);
+		data->oversampling_humid = ilog2(16);
+		data->oversampling_temp = ilog2(2);
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -895,6 +1089,7 @@ static const struct acpi_device_id bmp280_acpi_match[] = {
 	{"BMP0280", BMP280_CHIP_ID },
 	{"BMP0180", BMP180_CHIP_ID },
 	{"BMP0085", BMP180_CHIP_ID },
+	{"BME0280", BME280_CHIP_ID },
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, bmp280_acpi_match);
@@ -903,6 +1098,7 @@ static const struct i2c_device_id bmp280_id[] = {
 	{"bmp280", BMP280_CHIP_ID },
 	{"bmp180", BMP180_CHIP_ID },
 	{"bmp085", BMP180_CHIP_ID },
+	{"bme280", BME280_CHIP_ID },
 	{ },
 };
 MODULE_DEVICE_TABLE(i2c, bmp280_id);