iio: bmg160: add callbacks for the filter frequency
The filter frequency and sample rate have a fixed relationship.
Only the filter frequency is unique, however.
Currently the driver ignores the filter settings for 32 Hz and
64 Hz.
This patch adds the necessary callbacks to be able to configure
and read the filter setting from sysfs.
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/gyro/bmg160_core.c b/drivers/iio/gyro/bmg160_core.c
index 8155251..f7fcfa8 100644
--- a/drivers/iio/gyro/bmg160_core.c
+++ b/drivers/iio/gyro/bmg160_core.c
@@ -50,6 +50,7 @@
#define BMG160_REG_PMU_BW 0x10
#define BMG160_NO_FILTER 0
#define BMG160_DEF_BW 100
+#define BMG160_REG_PMU_BW_RES BIT(7)
#define BMG160_REG_INT_MAP_0 0x17
#define BMG160_INT_MAP_0_BIT_ANY BIT(1)
@@ -100,7 +101,6 @@
struct iio_trigger *motion_trig;
struct mutex mutex;
s16 buffer[8];
- u8 bw_bits;
u32 dps_range;
int ev_enable_state;
int slope_thres;
@@ -117,13 +117,16 @@
};
static const struct {
- int val;
+ int odr;
+ int filter;
int bw_bits;
-} bmg160_samp_freq_table[] = { {100, 0x07},
- {200, 0x06},
- {400, 0x03},
- {1000, 0x02},
- {2000, 0x01} };
+} bmg160_samp_freq_table[] = { {100, 32, 0x07},
+ {200, 64, 0x06},
+ {100, 12, 0x05},
+ {200, 23, 0x04},
+ {400, 47, 0x03},
+ {1000, 116, 0x02},
+ {2000, 230, 0x01} };
static const struct {
int scale;
@@ -153,7 +156,7 @@
int i;
for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
- if (bmg160_samp_freq_table[i].val == val)
+ if (bmg160_samp_freq_table[i].odr == val)
return bmg160_samp_freq_table[i].bw_bits;
}
@@ -176,7 +179,53 @@
return ret;
}
- data->bw_bits = bw_bits;
+ return 0;
+}
+
+static int bmg160_get_filter(struct bmg160_data *data, int *val)
+{
+ struct device *dev = regmap_get_device(data->regmap);
+ int ret;
+ int i;
+ unsigned int bw_bits;
+
+ ret = regmap_read(data->regmap, BMG160_REG_PMU_BW, &bw_bits);
+ if (ret < 0) {
+ dev_err(dev, "Error reading reg_pmu_bw\n");
+ return ret;
+ }
+
+ /* Ignore the readonly reserved bit. */
+ bw_bits &= ~BMG160_REG_PMU_BW_RES;
+
+ for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
+ if (bmg160_samp_freq_table[i].bw_bits == bw_bits)
+ break;
+ }
+
+ *val = bmg160_samp_freq_table[i].filter;
+
+ return ret ? ret : IIO_VAL_INT;
+}
+
+
+static int bmg160_set_filter(struct bmg160_data *data, int val)
+{
+ struct device *dev = regmap_get_device(data->regmap);
+ int ret;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
+ if (bmg160_samp_freq_table[i].filter == val)
+ break;
+ }
+
+ ret = regmap_write(data->regmap, BMG160_REG_PMU_BW,
+ bmg160_samp_freq_table[i].bw_bits);
+ if (ret < 0) {
+ dev_err(dev, "Error writing reg_pmu_bw\n");
+ return ret;
+ }
return 0;
}
@@ -386,11 +435,23 @@
static int bmg160_get_bw(struct bmg160_data *data, int *val)
{
+ struct device *dev = regmap_get_device(data->regmap);
int i;
+ unsigned int bw_bits;
+ int ret;
+
+ ret = regmap_read(data->regmap, BMG160_REG_PMU_BW, &bw_bits);
+ if (ret < 0) {
+ dev_err(dev, "Error reading reg_pmu_bw\n");
+ return ret;
+ }
+
+ /* Ignore the readonly reserved bit. */
+ bw_bits &= ~BMG160_REG_PMU_BW_RES;
for (i = 0; i < ARRAY_SIZE(bmg160_samp_freq_table); ++i) {
- if (bmg160_samp_freq_table[i].bw_bits == data->bw_bits) {
- *val = bmg160_samp_freq_table[i].val;
+ if (bmg160_samp_freq_table[i].bw_bits == bw_bits) {
+ *val = bmg160_samp_freq_table[i].odr;
return IIO_VAL_INT;
}
}
@@ -507,6 +568,8 @@
return IIO_VAL_INT;
} else
return -EINVAL;
+ case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+ return bmg160_get_filter(data, val);
case IIO_CHAN_INFO_SCALE:
*val = 0;
switch (chan->type) {
@@ -571,6 +634,26 @@
ret = bmg160_set_power_state(data, false);
mutex_unlock(&data->mutex);
return ret;
+ case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+ if (val2)
+ return -EINVAL;
+
+ mutex_lock(&data->mutex);
+ ret = bmg160_set_power_state(data, true);
+ if (ret < 0) {
+ bmg160_set_power_state(data, false);
+ mutex_unlock(&data->mutex);
+ return ret;
+ }
+ ret = bmg160_set_filter(data, val);
+ if (ret < 0) {
+ bmg160_set_power_state(data, false);
+ mutex_unlock(&data->mutex);
+ return ret;
+ }
+ ret = bmg160_set_power_state(data, false);
+ mutex_unlock(&data->mutex);
+ return ret;
case IIO_CHAN_INFO_SCALE:
if (val)
return -EINVAL;
@@ -728,7 +811,8 @@
.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), \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+ BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), \
.scan_index = AXIS_##_axis, \
.scan_type = { \
.sign = 's', \