iio: accel: Add sampling rate support for STK8BA50

Added support for setting the STK8BA50 accelerometer's
sampling rate.

Signed-off-by: Tiberiu Breana <tiberiu.a.breana@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
Tiberiu Breana 2015-06-10 18:07:30 +03:00 committed by Jonathan Cameron
parent 003f4880bd
commit eb2c9ce2cc
1 changed files with 50 additions and 7 deletions

View File

@ -21,6 +21,7 @@
#define STK8BA50_REG_YOUT 0x04
#define STK8BA50_REG_ZOUT 0x06
#define STK8BA50_REG_RANGE 0x0F
#define STK8BA50_REG_BWSEL 0x10
#define STK8BA50_REG_POWMODE 0x11
#define STK8BA50_REG_SWRST 0x14
@ -29,6 +30,7 @@
#define STK8BA50_MODE_POWERBIT BIT(7)
#define STK8BA50_DATA_SHIFT 6
#define STK8BA50_RESET_CMD 0xB6
#define STK8BA50_SR_1792HZ_IDX 7
#define STK8BA50_DRIVER_NAME "stk8ba50"
@ -57,10 +59,20 @@ static const struct {
{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
};
/* Sample rates are stored as { <register value>, <Hz value> } */
static const struct {
u8 reg_val;
u16 samp_freq;
} stk8ba50_samp_freq_table[] = {
{0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
};
struct stk8ba50_data {
struct i2c_client *client;
struct mutex lock;
int range;
u8 sample_rate_idx;
};
#define STK8BA50_ACCEL_CHANNEL(reg, axis) { \
@ -70,6 +82,7 @@ struct stk8ba50_data {
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
}
static const struct iio_chan_spec stk8ba50_channels[] = {
@ -80,8 +93,11 @@ static const struct iio_chan_spec stk8ba50_channels[] = {
static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
static struct attribute *stk8ba50_attributes[] = {
&iio_const_attr_in_accel_scale_available.dev_attr.attr,
&iio_const_attr_sampling_frequency_available.dev_attr.attr,
NULL,
};
@ -119,6 +135,11 @@ static int stk8ba50_read_raw(struct iio_dev *indio_dev,
*val = 0;
*val2 = stk8ba50_scale_table[data->range].scale_val;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SAMP_FREQ:
*val = stk8ba50_samp_freq_table
[data->sample_rate_idx].samp_freq;
*val2 = 0;
return IIO_VAL_INT;
}
return -EINVAL;
@ -155,6 +176,25 @@ static int stk8ba50_write_raw(struct iio_dev *indio_dev,
else
data->range = index;
return ret;
case IIO_CHAN_INFO_SAMP_FREQ:
for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
if (val == stk8ba50_samp_freq_table[i].samp_freq) {
index = i;
break;
}
if (index < 0)
return -EINVAL;
ret = i2c_smbus_write_byte_data(data->client,
STK8BA50_REG_BWSEL,
stk8ba50_samp_freq_table[index].reg_val);
if (ret < 0)
dev_err(&data->client->dev,
"failed to set sampling rate\n");
else
data->sample_rate_idx = index;
return ret;
}
@ -231,6 +271,9 @@ static int stk8ba50_probe(struct i2c_client *client,
/* The default range is +/-2g */
data->range = 0;
/* The default sampling rate is 1792 Hz (maximum) */
data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev, "device_register failed\n");