staging:iio:hmc5843: Add trigger handling

v3:
* use __be16 instead of s16
v2 (thanks to Jonathan Cameron):
* drop dynamic buffer allocation, buffer is in hmc5842_data
* grab timestamp near data acquisition
* restrict available scan masks (only read all axis)

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
Peter Meerwald 2013-10-16 23:19:00 +01:00 committed by Jonathan Cameron
parent 39c1882882
commit cb9b9a828f

View file

@ -23,6 +23,9 @@
#include <linux/i2c.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/buffer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/delay.h>
#define HMC5843_CONFIG_REG_A 0x00
@ -124,6 +127,7 @@ struct hmc5843_data {
u8 operating_mode;
u8 range;
const struct hmc5843_chip_info *variant;
__be16 buffer[8]; /* 3x 16-bit channels + padding + 64-bit timestamp */
};
/* The lower two bits contain the current conversion mode */
@ -403,7 +407,7 @@ static int hmc5843_read_raw(struct iio_dev *indio_dev,
switch (mask) {
case IIO_CHAN_INFO_RAW:
return hmc5843_read_measurement(data, chan->address, val);
return hmc5843_read_measurement(data, chan->scan_index, val);
case IIO_CHAN_INFO_SCALE:
*val = 0;
*val2 = data->variant->regval_to_nanoscale[data->range];
@ -468,6 +472,36 @@ static int hmc5843_write_raw_get_fmt(struct iio_dev *indio_dev,
}
}
static irqreturn_t hmc5843_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct hmc5843_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->lock);
ret = hmc5843_wait_measurement(data);
if (ret < 0) {
mutex_unlock(&data->lock);
goto done;
}
ret = i2c_smbus_read_i2c_block_data(data->client,
HMC5843_DATA_OUT_MSB_REGS, 3 * sizeof(__be16),
(u8 *) data->buffer);
mutex_unlock(&data->lock);
if (ret < 0)
goto done;
iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
iio_get_time_ns());
done:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
#define HMC5843_CHANNEL(axis, idx) \
{ \
.type = IIO_MAGN, \
@ -476,13 +510,15 @@ static int hmc5843_write_raw_get_fmt(struct iio_dev *indio_dev,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.address = idx \
.scan_index = idx, \
.scan_type = IIO_ST('s', 16, 16, IIO_BE), \
}
static const struct iio_chan_spec hmc5843_channels[] = {
HMC5843_CHANNEL(X, 0),
HMC5843_CHANNEL(Y, 1),
HMC5843_CHANNEL(Z, 2),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
/* Beware: Y and Z are exchanged on HMC5883 */
@ -490,6 +526,7 @@ static const struct iio_chan_spec hmc5883_channels[] = {
HMC5843_CHANNEL(X, 0),
HMC5843_CHANNEL(Z, 1),
HMC5843_CHANNEL(Y, 2),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
static struct attribute *hmc5843_attributes[] = {
@ -539,12 +576,14 @@ static const struct iio_info hmc5843_info = {
.driver_module = THIS_MODULE,
};
static const unsigned long hmc5843_scan_masks[] = {0x7, 0};
static int hmc5843_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct hmc5843_data *data;
struct iio_dev *indio_dev;
int err = 0;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (indio_dev == NULL)
@ -562,20 +601,34 @@ static int hmc5843_probe(struct i2c_client *client,
indio_dev->dev.parent = &client->dev;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = data->variant->channels;
indio_dev->num_channels = 3;
indio_dev->num_channels = 4;
indio_dev->available_scan_masks = hmc5843_scan_masks;
hmc5843_init(data);
err = iio_device_register(indio_dev);
if (err)
return err;
ret = iio_triggered_buffer_setup(indio_dev, NULL,
hmc5843_trigger_handler, NULL);
if (ret < 0)
return ret;
ret = iio_device_register(indio_dev);
if (ret < 0)
goto buffer_cleanup;
return 0;
buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
return ret;
}
static int hmc5843_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);
/* sleep mode to save power */
hmc5843_configure(client, HMC5843_MODE_SLEEP);