staging:iio:hmc5843: Always read all channels values otherwise no updates

v2:
* use __be16 instead of s16

Split out data ready/wait for read measurement
fix bug in case reading status register fails

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 9a3b2d5e0c
commit 39c1882882
1 changed files with 32 additions and 21 deletions

View File

@ -28,12 +28,7 @@
#define HMC5843_CONFIG_REG_A 0x00
#define HMC5843_CONFIG_REG_B 0x01
#define HMC5843_MODE_REG 0x02
#define HMC5843_DATA_OUT_X_MSB_REG 0x03
#define HMC5843_DATA_OUT_Y_MSB_REG 0x05
#define HMC5843_DATA_OUT_Z_MSB_REG 0x07
/* Beware: Y and Z are exchanged on HMC5883 */
#define HMC5883_DATA_OUT_Z_MSB_REG 0x05
#define HMC5883_DATA_OUT_Y_MSB_REG 0x07
#define HMC5843_DATA_OUT_MSB_REGS 0x03
#define HMC5843_STATUS_REG 0x09
enum hmc5843_ids {
@ -140,17 +135,16 @@ static s32 hmc5843_configure(struct i2c_client *client,
operating_mode & HMC5843_MODE_MASK);
}
/* Return the measurement value from the specified channel */
static int hmc5843_read_measurement(struct hmc5843_data *data,
int address, int *val)
static int hmc5843_wait_measurement(struct hmc5843_data *data)
{
s32 result;
int tries = 150;
mutex_lock(&data->lock);
while (tries-- > 0) {
result = i2c_smbus_read_byte_data(data->client,
HMC5843_STATUS_REG);
if (result < 0)
return result;
if (result & HMC5843_DATA_READY)
break;
msleep(20);
@ -158,16 +152,32 @@ static int hmc5843_read_measurement(struct hmc5843_data *data,
if (tries < 0) {
dev_err(&data->client->dev, "data not ready\n");
mutex_unlock(&data->lock);
return -EIO;
}
result = i2c_smbus_read_word_swapped(data->client, address);
return 0;
}
/* Return the measurement value from the specified channel */
static int hmc5843_read_measurement(struct hmc5843_data *data,
int idx, int *val)
{
s32 result;
__be16 values[3];
mutex_lock(&data->lock);
result = hmc5843_wait_measurement(data);
if (result < 0) {
mutex_unlock(&data->lock);
return result;
}
result = i2c_smbus_read_i2c_block_data(data->client,
HMC5843_DATA_OUT_MSB_REGS, sizeof(values), (u8 *) values);
mutex_unlock(&data->lock);
if (result < 0)
return -EINVAL;
*val = sign_extend32(result, 15);
*val = sign_extend32(be16_to_cpu(values[idx]), 15);
return IIO_VAL_INT;
}
@ -458,7 +468,7 @@ static int hmc5843_write_raw_get_fmt(struct iio_dev *indio_dev,
}
}
#define HMC5843_CHANNEL(axis, addr) \
#define HMC5843_CHANNEL(axis, idx) \
{ \
.type = IIO_MAGN, \
.modified = 1, \
@ -466,19 +476,20 @@ 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 = addr \
.address = idx \
}
static const struct iio_chan_spec hmc5843_channels[] = {
HMC5843_CHANNEL(X, HMC5843_DATA_OUT_X_MSB_REG),
HMC5843_CHANNEL(Y, HMC5843_DATA_OUT_Y_MSB_REG),
HMC5843_CHANNEL(Z, HMC5843_DATA_OUT_Z_MSB_REG),
HMC5843_CHANNEL(X, 0),
HMC5843_CHANNEL(Y, 1),
HMC5843_CHANNEL(Z, 2),
};
/* Beware: Y and Z are exchanged on HMC5883 */
static const struct iio_chan_spec hmc5883_channels[] = {
HMC5843_CHANNEL(X, HMC5843_DATA_OUT_X_MSB_REG),
HMC5843_CHANNEL(Y, HMC5883_DATA_OUT_Y_MSB_REG),
HMC5843_CHANNEL(Z, HMC5883_DATA_OUT_Z_MSB_REG),
HMC5843_CHANNEL(X, 0),
HMC5843_CHANNEL(Z, 1),
HMC5843_CHANNEL(Y, 2),
};
static struct attribute *hmc5843_attributes[] = {