Commit 1ce0eda0 authored by Teodora Baluta's avatar Teodora Baluta Committed by Jonathan Cameron
Browse files

iio: mxc4005: add triggered buffer mode for mxc4005 



This patch adds support for buffered readings for the 3-axis
accelerometer mxc4005.

Signed-off-by: default avatarTeodora Baluta <teodora.baluta@intel.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 077377fc

drivers/iio/accel/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -140,6 +140,8 @@ config MMA9553 
config MXC4005

	tristate "Memsic MXC4005XC 3-Axis Accelerometer Driver"

	depends on I2C

	select IIO_BUFFER

	select IIO_TRIGGERED_BUFFER

	select REGMAP_I2C

	help

	  Say yes here to build support for the Memsic MXC4005XC 3-axis

drivers/iio/accel/mxc4005.c

+76 −3
Original line number Diff line number Diff line
@@ -19,6 +19,9 @@ 
#include <linux/acpi.h>

#include <linux/regmap.h>

#include <linux/iio/sysfs.h>

#include <linux/iio/buffer.h>

#include <linux/iio/triggered_buffer.h>

#include <linux/iio/trigger_consumer.h>



#define MXC4005_DRV_NAME		"mxc4005"

#define MXC4005_REGMAP_NAME		"mxc4005_regmap"
@@ -52,6 +55,7 @@ struct mxc4005_data { 
	struct device *dev;

	struct mutex mutex;

	struct regmap *regmap;

	__be16 buffer[8];

};



/*
@@ -122,6 +126,20 @@ static const struct regmap_config mxc4005_regmap_config = { 
	.writeable_reg = mxc4005_is_writeable_reg,

};



static int mxc4005_read_xyz(struct mxc4005_data *data)

{

	int ret;



	ret = regmap_bulk_read(data->regmap, MXC4005_REG_XOUT_UPPER,

			       (u8 *) data->buffer, sizeof(data->buffer));

	if (ret < 0) {

		dev_err(data->dev, "failed to read axes\n");

		return ret;

	}



	return 0;

}



static int mxc4005_read_axis(struct mxc4005_data *data,

			     unsigned int addr)

{
@@ -197,7 +215,8 @@ static int mxc4005_read_raw(struct iio_dev *indio_dev, 
			ret = mxc4005_read_axis(data, chan->address);

			if (ret < 0)

				return ret;

			*val = sign_extend32(ret >> 4, 11);

			*val = sign_extend32(ret >> chan->scan_type.shift,

					     chan->scan_type.realbits - 1);

			return IIO_VAL_INT;

		default:

			return -EINVAL;
@@ -239,6 +258,11 @@ static const struct iio_info mxc4005_info = { 
	.attrs		= &mxc4005_attrs_group,

};



static const unsigned long mxc4005_scan_masks[] = {

	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),

	0

};



#define MXC4005_CHANNEL(_axis, _addr) {				\

	.type = IIO_ACCEL,					\

	.modified = 1,						\
@@ -246,14 +270,43 @@ static const struct iio_info mxc4005_info = { 
	.address = _addr,					\

	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\

	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\

	.scan_index = AXIS_##_axis,				\

	.scan_type = {						\

		.sign = 's',					\

		.realbits = 12,					\

		.storagebits = 16,				\

		.shift = 4,					\

		.endianness = IIO_BE,				\

	},							\

}



static const struct iio_chan_spec mxc4005_channels[] = {

	MXC4005_CHANNEL(X, MXC4005_REG_XOUT_UPPER),

	MXC4005_CHANNEL(Y, MXC4005_REG_YOUT_UPPER),

	MXC4005_CHANNEL(Z, MXC4005_REG_ZOUT_UPPER),

	IIO_CHAN_SOFT_TIMESTAMP(3),

};



static irqreturn_t mxc4005_trigger_handler(int irq, void *private)

{

	struct iio_poll_func *pf = private;

	struct iio_dev *indio_dev = pf->indio_dev;

	struct mxc4005_data *data = iio_priv(indio_dev);

	int ret;



	ret = mxc4005_read_xyz(data);

	if (ret < 0)

		goto err;



	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,

					   pf->timestamp);



err:

	iio_trigger_notify_done(indio_dev->trig);



	return IRQ_HANDLED;

}



static int mxc4005_chip_init(struct mxc4005_data *data)

{

	int ret;
@@ -304,23 +357,43 @@ static int mxc4005_probe(struct i2c_client *client, 
	indio_dev->dev.parent = &client->dev;

	indio_dev->channels = mxc4005_channels;

	indio_dev->num_channels = ARRAY_SIZE(mxc4005_channels);

	indio_dev->available_scan_masks = mxc4005_scan_masks;

	indio_dev->name = MXC4005_DRV_NAME;

	indio_dev->modes = INDIO_DIRECT_MODE;

	indio_dev->info = &mxc4005_info;



	ret = iio_triggered_buffer_setup(indio_dev,

					 &iio_pollfunc_store_time,

					 mxc4005_trigger_handler,

					 NULL);

	if (ret < 0) {

		dev_err(&client->dev,

			"failed to setup iio triggered buffer\n");

		return ret;

	}



	ret = iio_device_register(indio_dev);

	if (ret < 0) {

		dev_err(&client->dev,

			"unable to register iio device %d\n", ret);

		return ret;

		goto err_buffer_cleanup;

	}



	return 0;



err_buffer_cleanup:

	iio_triggered_buffer_cleanup(indio_dev);



	return ret;

}



static int mxc4005_remove(struct i2c_client *client)

{

	iio_device_unregister(i2c_get_clientdata(client));

	struct iio_dev *indio_dev = i2c_get_clientdata(client);



	iio_device_unregister(indio_dev);



	iio_triggered_buffer_cleanup(indio_dev);



	return 0;

}