Commit 16bf793f authored by Alison Schofield's avatar Alison Schofield Committed by Jonathan Cameron
Browse files

iio: humidity: hdc100x: add triggered buffer support for HDC100X 



Triggered buffer support uses the HDC100X's dual acquisition mode
to read both humidity and temperature in one shot.

This patch depends on
	447136effbf4 ("iio: humidity: hdc100x: fix sensor data reads of
		       temp and humidity")

Signed-off-by: default avatarAlison Schofield <amsfield22@gmail.com>
Cc: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 88e39a88

drivers/iio/humidity/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -27,6 +27,8 @@ config DHT11 
config HDC100X

	tristate "TI HDC100x relative humidity and temperature sensor"

	depends on I2C

	select IIO_BUFFER

	select IIO_TRIGGERED_BUFFER

	help

	  Say yes here to build support for the Texas Instruments

	  HDC1000 and HDC1008 relative humidity and temperature sensors.

drivers/iio/humidity/hdc100x.c

+128 −2
Original line number Diff line number Diff line
@@ -22,11 +22,15 @@ 


#include <linux/iio/iio.h>

#include <linux/iio/sysfs.h>

#include <linux/iio/buffer.h>

#include <linux/iio/trigger_consumer.h>

#include <linux/iio/triggered_buffer.h>



#define HDC100X_REG_TEMP			0x00

#define HDC100X_REG_HUMIDITY			0x01



#define HDC100X_REG_CONFIG			0x02

#define HDC100X_REG_CONFIG_ACQ_MODE		BIT(12)

#define HDC100X_REG_CONFIG_HEATER_EN		BIT(13)



struct hdc100x_data {
@@ -87,22 +91,40 @@ static const struct iio_chan_spec hdc100x_channels[] = { 
			BIT(IIO_CHAN_INFO_SCALE) |

			BIT(IIO_CHAN_INFO_INT_TIME) |

			BIT(IIO_CHAN_INFO_OFFSET),

		.scan_index = 0,

		.scan_type = {

			.sign = 's',

			.realbits = 16,

			.storagebits = 16,

			.endianness = IIO_BE,

		},

	},

	{

		.type = IIO_HUMIDITYRELATIVE,

		.address = HDC100X_REG_HUMIDITY,

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |

			BIT(IIO_CHAN_INFO_SCALE) |

			BIT(IIO_CHAN_INFO_INT_TIME)

			BIT(IIO_CHAN_INFO_INT_TIME),

		.scan_index = 1,

		.scan_type = {

			.sign = 'u',

			.realbits = 16,

			.storagebits = 16,

			.endianness = IIO_BE,

		},

	},

	{

		.type = IIO_CURRENT,

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

		.extend_name = "heater",

		.output = 1,

		.scan_index = -1,

	},

	IIO_CHAN_SOFT_TIMESTAMP(2),

};



static const unsigned long hdc100x_scan_masks[] = {0x3, 0};



static int hdc100x_update_config(struct hdc100x_data *data, int mask, int val)

{

	int tmp = (~mask & data->config) | val;
@@ -183,7 +205,14 @@ static int hdc100x_read_raw(struct iio_dev *indio_dev, 
			*val = hdc100x_get_heater_status(data);

			ret = IIO_VAL_INT;

		} else {

			ret = iio_device_claim_direct_mode(indio_dev);

			if (ret) {

				mutex_unlock(&data->lock);

				return ret;

			}



			ret = hdc100x_get_measurement(data, chan);

			iio_device_release_direct_mode(indio_dev);

			if (ret >= 0) {

				*val = ret;

				ret = IIO_VAL_INT;
@@ -246,6 +275,78 @@ static int hdc100x_write_raw(struct iio_dev *indio_dev, 
	}

}



static int hdc100x_buffer_postenable(struct iio_dev *indio_dev)

{

	struct hdc100x_data *data = iio_priv(indio_dev);

	int ret;



	/* Buffer is enabled. First set ACQ Mode, then attach poll func */

	mutex_lock(&data->lock);

	ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE,

				    HDC100X_REG_CONFIG_ACQ_MODE);

	mutex_unlock(&data->lock);

	if (ret)

		return ret;



	return iio_triggered_buffer_postenable(indio_dev);

}



static int hdc100x_buffer_predisable(struct iio_dev *indio_dev)

{

	struct hdc100x_data *data = iio_priv(indio_dev);

	int ret;



	/* First detach poll func, then reset ACQ mode. OK to disable buffer */

	ret = iio_triggered_buffer_predisable(indio_dev);

	if (ret)

		return ret;



	mutex_lock(&data->lock);

	ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);

	mutex_unlock(&data->lock);



	return ret;

}



static const struct iio_buffer_setup_ops hdc_buffer_setup_ops = {

	.postenable  = hdc100x_buffer_postenable,

	.predisable  = hdc100x_buffer_predisable,

};



static irqreturn_t hdc100x_trigger_handler(int irq, void *p)

{

	struct iio_poll_func *pf = p;

	struct iio_dev *indio_dev = pf->indio_dev;

	struct hdc100x_data *data = iio_priv(indio_dev);

	struct i2c_client *client = data->client;

	int delay = data->adc_int_us[0] + data->adc_int_us[1];

	int ret;

	s16 buf[8];  /* 2x s16 + padding + 8 byte timestamp */



	/* dual read starts at temp register */

	mutex_lock(&data->lock);

	ret = i2c_smbus_write_byte(client, HDC100X_REG_TEMP);

	if (ret < 0) {

		dev_err(&client->dev, "cannot start measurement\n");

		goto err;

	}

	usleep_range(delay, delay + 1000);



	ret = i2c_master_recv(client, (u8 *)buf, 4);

	if (ret < 0) {

		dev_err(&client->dev, "cannot read sensor data\n");

		goto err;

	}



	iio_push_to_buffers_with_timestamp(indio_dev, buf,

					   iio_get_time_ns(indio_dev));

err:

	mutex_unlock(&data->lock);

	iio_trigger_notify_done(indio_dev->trig);



	return IRQ_HANDLED;

}



static const struct iio_info hdc100x_info = {

	.read_raw = hdc100x_read_raw,

	.write_raw = hdc100x_write_raw,
@@ -258,6 +359,7 @@ static int hdc100x_probe(struct i2c_client *client, 
{

	struct iio_dev *indio_dev;

	struct hdc100x_data *data;

	int ret;



	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |

				     I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
@@ -279,12 +381,35 @@ static int hdc100x_probe(struct i2c_client *client, 


	indio_dev->channels = hdc100x_channels;

	indio_dev->num_channels = ARRAY_SIZE(hdc100x_channels);

	indio_dev->available_scan_masks = hdc100x_scan_masks;



	/* be sure we are in a known state */

	hdc100x_set_it_time(data, 0, hdc100x_int_time[0][0]);

	hdc100x_set_it_time(data, 1, hdc100x_int_time[1][0]);

	hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);



	ret = iio_triggered_buffer_setup(indio_dev, NULL,

					 hdc100x_trigger_handler,

					 &hdc_buffer_setup_ops);

	if (ret < 0) {

		dev_err(&client->dev, "iio triggered buffer setup failed\n");

		return ret;

	}

	ret = iio_device_register(indio_dev);

	if (ret < 0)

		iio_triggered_buffer_cleanup(indio_dev);



	return ret;

}



static int hdc100x_remove(struct i2c_client *client)

{

	struct iio_dev *indio_dev = i2c_get_clientdata(client);



	iio_device_unregister(indio_dev);

	iio_triggered_buffer_cleanup(indio_dev);



	return devm_iio_device_register(&client->dev, indio_dev);

	return 0;

}



static const struct i2c_device_id hdc100x_id[] = {
@@ -298,6 +423,7 @@ static struct i2c_driver hdc100x_driver = { 
		.name	= "hdc100x",

	},

	.probe = hdc100x_probe,

	.remove = hdc100x_remove,

	.id_table = hdc100x_id,

};

module_i2c_driver(hdc100x_driver);

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