Commit b81fbab7 authored by Peter Meerwald's avatar Peter Meerwald Committed by Jonathan Cameron
Browse files

iio:bma180: Expose temperature channel 



8-bit signed; 0 LSB @ 24 °C, 0.5 °C per LSB

Signed-off-by: default avatarPeter Meerwald <pmeerw@pmeerw.net>
Cc: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent c7c69e85

drivers/iio/accel/bma180.c

+59 −21
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
/* Register set */

#define BMA180_CHIP_ID		0x00 /* Need to distinguish BMA180 from other */

#define BMA180_ACC_X_LSB	0x02 /* First of 6 registers of accel data */

#define BMA180_TEMP		0x08

#define BMA180_CTRL_REG0	0x0d

#define BMA180_RESET		0x10

#define BMA180_BW_TCS		0x20
@@ -84,27 +85,37 @@ struct bma180_data { 
	char *buff;

};



enum bma180_axis {

enum bma180_chan {

	AXIS_X,

	AXIS_Y,

	AXIS_Z,

	TEMP

};



static int bma180_bw_table[] = { 10, 20, 40, 75, 150, 300 }; /* Hz */

static int bma180_scale_table[] = { 1275, 1863, 2452, 3727, 4903, 9709, 19417 };



static int bma180_get_acc_reg(struct bma180_data *data, enum bma180_axis axis)

static int bma180_get_data_reg(struct bma180_data *data, enum bma180_chan chan)

{

	u8 reg = BMA180_ACC_X_LSB + axis * 2;

	int ret;



	if (data->sleep_state)

		return -EBUSY;



	ret = i2c_smbus_read_word_data(data->client, reg);

	switch (chan) {

	case TEMP:

		ret = i2c_smbus_read_byte_data(data->client, BMA180_TEMP);

		if (ret < 0)

			dev_err(&data->client->dev, "failed to read temp register\n");

		break;

	default:

		ret = i2c_smbus_read_word_data(data->client,

			BMA180_ACC_X_LSB + chan * 2);

		if (ret < 0)

			dev_err(&data->client->dev,

			"failed to read accel_%c register\n", 'x' + axis);

				"failed to read accel_%c register\n",

				'x' + chan);

	}



	return ret;

}
@@ -337,22 +348,35 @@ static int bma180_read_raw(struct iio_dev *indio_dev, 
	switch (mask) {

	case IIO_CHAN_INFO_RAW:

		mutex_lock(&data->mutex);

		if (iio_buffer_enabled(indio_dev))

			ret = -EBUSY;

		else

			ret = bma180_get_acc_reg(data, chan->scan_index);

		if (iio_buffer_enabled(indio_dev)) {

			mutex_unlock(&data->mutex);

			return -EBUSY;

		}

		ret = bma180_get_data_reg(data, chan->scan_index);

		mutex_unlock(&data->mutex);

		if (ret < 0)

			return ret;

		*val = (s16)ret >> chan->scan_type.shift;

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

			chan->scan_type.realbits - 1);

		return IIO_VAL_INT;

	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:

		*val = data->bw;

		return IIO_VAL_INT;

	case IIO_CHAN_INFO_SCALE:

		switch (chan->type) {

		case IIO_ACCEL:

			*val = 0;

			*val2 = data->scale;

			return IIO_VAL_INT_PLUS_MICRO;

		case IIO_TEMP:

			*val = 500;

			return IIO_VAL_INT;

		default:

			return -EINVAL;

		}

	case IIO_CHAN_INFO_OFFSET:

		*val = 48; /* 0 LSB @ 24 degree C */

		return IIO_VAL_INT;

	default:

		return -EINVAL;

	}
@@ -443,7 +467,7 @@ static const struct iio_chan_spec_ext_info bma180_ext_info[] = { 
	{ },

};



#define BMA180_CHANNEL(_axis) {					\

#define BMA180_ACC_CHANNEL(_axis) {					\

	.type = IIO_ACCEL,						\

	.modified = 1,							\

	.channel2 = IIO_MOD_##_axis,					\
@@ -460,11 +484,24 @@ static const struct iio_chan_spec_ext_info bma180_ext_info[] = { 
	.ext_info = bma180_ext_info,					\

}



#define BMA180_TEMP_CHANNEL {						\

	.type = IIO_TEMP,						\

	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\

		BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET),	\

	.scan_index = TEMP,						\

	.scan_type = {							\

		.sign = 's',						\

		.realbits = 8,						\

		.storagebits = 16,					\

	},								\

}



static const struct iio_chan_spec bma180_channels[] = {

	BMA180_CHANNEL(X),

	BMA180_CHANNEL(Y),

	BMA180_CHANNEL(Z),

	IIO_CHAN_SOFT_TIMESTAMP(3),

	BMA180_ACC_CHANNEL(X),

	BMA180_ACC_CHANNEL(Y),

	BMA180_ACC_CHANNEL(Z),

	BMA180_TEMP_CHANNEL,

	IIO_CHAN_SOFT_TIMESTAMP(4),

};



static irqreturn_t bma180_trigger_handler(int irq, void *p)
@@ -479,13 +516,14 @@ static irqreturn_t bma180_trigger_handler(int irq, void *p) 


	for_each_set_bit(bit, indio_dev->buffer->scan_mask,

			 indio_dev->masklength) {

		ret = bma180_get_acc_reg(data, bit);

		ret = bma180_get_data_reg(data, bit);

		if (ret < 0) {

			mutex_unlock(&data->mutex);

			goto err;

		}

		((s16 *)data->buff)[i++] = ret;

	}



	mutex_unlock(&data->mutex);



	iio_push_to_buffers_with_timestamp(indio_dev, data->buff, time_ns);