[PATCH v3 6/6] iio: imu: bmi270: Add scale and sampling frequency to BMI270 IMU

Justin Weiss
2024-10-20T22:01:31Z

Add read and write functions and create _available entries.

Signed-off-by: Justin Weiss <justin@justinweiss.com>
---
drivers/iio/imu/bmi270/bmi270_core.c | 340 +++++++++++++++++++++++++++
1 file changed, 340 insertions(+)

diff --git a/drivers/iio/imu/bmi270/bmi270_core.c b/drivers/iio/imu/bmi270/bmi270_core.c
index 5b643afae9f7..3e1e698c4af0 100644
--- a/drivers/iio/imu/bmi270/bmi270_core.c
+++ b/drivers/iio/imu/bmi270/bmi270_core.c
@@ -7,6 +7,7 @@
#include <linux/regmap.h>

#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>

@@ -38,6 +39,9 @@
#define BMI270_ACC_CONF_BWP_NORMAL_MODE 0x02
#define BMI270_ACC_CONF_FILTER_PERF_MSK BIT(7)

+#define BMI270_ACC_CONF_RANGE_REG 0x41
+#define BMI270_ACC_CONF_RANGE_MSK GENMASK(1, 0)
+
#define BMI270_GYR_CONF_REG 0x42
#define BMI270_GYR_CONF_ODR_MSK GENMASK(3, 0)
#define BMI270_GYR_CONF_ODR_200HZ 0x09
@@ -46,6 +50,9 @@
#define BMI270_GYR_CONF_NOISE_PERF_MSK BIT(6)
#define BMI270_GYR_CONF_FILTER_PERF_MSK BIT(7)

+#define BMI270_GYR_CONF_RANGE_REG 0x43
+#define BMI270_GYR_CONF_RANGE_MSK GENMASK(2, 0)
+
#define BMI270_INIT_CTRL_REG 0x59
#define BMI270_INIT_CTRL_LOAD_DONE_MSK BIT(0)

@@ -99,6 +106,265 @@ const struct bmi270_chip_info bmi270_chip_info = {
};
EXPORT_SYMBOL_NS_GPL(bmi270_chip_info, IIO_BMI270);

+enum bmi270_sensor_type {
+ BMI270_ACCEL = 0,
+ BMI270_GYRO,
+};
+
+struct bmi270_scale {
+ int scale;
+ int uscale;
+};
+
+struct bmi270_odr {
+ int odr;
+ int uodr;
+};
+
+static const struct bmi270_scale bmi270_accel_scale[] = {
+ { 0, 598 },
+ { 0, 1197 },
+ { 0, 2394 },
+ { 0, 4788 },
+};
+
+static const struct bmi270_scale bmi270_gyro_scale[] = {
+ { 0, 1065 },
+ { 0, 532 },
+ { 0, 266 },
+ { 0, 133 },
+ { 0, 66 },
+};
+
+struct bmi270_scale_item {
+ const struct bmi270_scale *tbl;
+ int num;
+};
+
+static const struct bmi270_scale_item bmi270_scale_table[] = {
+ [BMI270_ACCEL] = {
+ .tbl = bmi270_accel_scale,
+ .num = ARRAY_SIZE(bmi270_accel_scale),
+ },
+ [BMI270_GYRO] = {
+ .tbl = bmi270_gyro_scale,
+ .num = ARRAY_SIZE(bmi270_gyro_scale),
+ },
+};
+
+static const struct bmi270_odr bmi270_accel_odr[] = {
+ { 0, 781250 },
+ { 1, 562500 },
+ { 3, 125000 },
+ { 6, 250000 },
+ { 12, 500000 },
+ { 25, 0 },
+ { 50, 0 },
+ { 100, 0 },
+ { 200, 0 },
+ { 400, 0 },
+ { 800, 0 },
+ { 1600, 0 },
+};
+
+static const u8 bmi270_accel_odr_vals[] = {
+ 0x01,
+ 0x02,
+ 0x03,
+ 0x04,
+ 0x05,
+ 0x06,
+ 0x07,
+ 0x08,
+ 0x09,
+ 0x0A,
+ 0x0B,
+ 0x0C,
+};
+
+static const struct bmi270_odr bmi270_gyro_odr[] = {
+ { 25, 0 },
+ { 50, 0 },
+ { 100, 0 },
+ { 200, 0 },
+ { 400, 0 },
+ { 800, 0 },
+ { 1600, 0 },
+ { 3200, 0 },
+};
+
+static const u8 bmi270_gyro_odr_vals[] = {
+ 0x06,
+ 0x07,
+ 0x08,
+ 0x09,
+ 0x0A,
+ 0x0B,
+ 0x0C,
+ 0x0D,
+};
+
+struct bmi270_odr_item {
+ const struct bmi270_odr *tbl;
+ const u8 *vals;
+ int num;
+};
+
+static const struct bmi270_odr_item bmi270_odr_table[] = {
+ [BMI270_ACCEL] = {
+ .tbl = bmi270_accel_odr,
+ .vals = bmi270_accel_odr_vals,
+ .num = ARRAY_SIZE(bmi270_accel_odr),
+ },
+ [BMI270_GYRO] = {
+ .tbl = bmi270_gyro_odr,
+ .vals = bmi270_gyro_odr_vals,
+ .num = ARRAY_SIZE(bmi270_gyro_odr),
+ },
+};
+
+static int bmi270_set_scale(struct bmi270_data *data,
+ int chan_type, int uscale)
+{
+ int i;
+ int reg, mask;
+ struct bmi270_scale_item bmi270_scale_item;
+
+ switch (chan_type) {
+ case IIO_ACCEL:
+ reg = BMI270_ACC_CONF_RANGE_REG;
+ mask = BMI270_ACC_CONF_RANGE_MSK;
+ bmi270_scale_item = bmi270_scale_table[BMI270_ACCEL];
+ break;
+ case IIO_ANGL_VEL:
+ reg = BMI270_GYR_CONF_RANGE_REG;
+ mask = BMI270_GYR_CONF_RANGE_MSK;
+ bmi270_scale_item = bmi270_scale_table[BMI270_GYRO];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ for (i = 0; i < bmi270_scale_item.num; i++) {
+ if (bmi270_scale_item.tbl[i].uscale != uscale)
+ continue;
+
+ return regmap_update_bits(data->regmap, reg, mask, i);
+ }
+
+ return -EINVAL;
+}
+
+static int bmi270_get_scale(struct bmi270_data *bmi270_device,
+ int chan_type, int *uscale)
+{
+ int ret;
+ unsigned int val;
+ struct bmi270_scale_item bmi270_scale_item;
+
+ switch (chan_type) {
+ case IIO_ACCEL:
+ ret = regmap_read(bmi270_device->regmap,
+ BMI270_ACC_CONF_RANGE_REG, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(BMI270_ACC_CONF_RANGE_MSK, val);
+ bmi270_scale_item = bmi270_scale_table[BMI270_ACCEL];
+ break;
+ case IIO_ANGL_VEL:
+ ret = regmap_read(bmi270_device->regmap,
+ BMI270_GYR_CONF_RANGE_REG, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(BMI270_GYR_CONF_RANGE_MSK, val);
+ bmi270_scale_item = bmi270_scale_table[BMI270_GYRO];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (val >= bmi270_scale_item.num)
+ return -EINVAL;
+
+ *uscale = bmi270_scale_item.tbl[val].uscale;
+ return 0;
+}
+
+static int bmi270_set_odr(struct bmi270_data *data, int chan_type,
+ int odr, int uodr)
+{
+ int i;
+ int reg, mask;
+ struct bmi270_odr_item bmi270_odr_item;
+
+ switch (chan_type) {
+ case IIO_ACCEL:
+ reg = BMI270_ACC_CONF_REG;
+ mask = BMI270_ACC_CONF_ODR_MSK;
+ bmi270_odr_item = bmi270_odr_table[BMI270_ACCEL];
+ break;
+ case IIO_ANGL_VEL:
+ reg = BMI270_GYR_CONF_REG;
+ mask = BMI270_GYR_CONF_ODR_MSK;
+ bmi270_odr_item = bmi270_odr_table[BMI270_GYRO];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ for (i = 0; i < bmi270_odr_item.num; i++) {
+ if (bmi270_odr_item.tbl[i].odr != odr ||
+ bmi270_odr_item.tbl[i].uodr != uodr)
+ continue;
+
+ return regmap_update_bits(data->regmap, reg, mask,
+ bmi270_odr_item.vals[i]);
+ }
+
+ return -EINVAL;
+}
+
+static int bmi270_get_odr(struct bmi270_data *data, int chan_type,
+ int *odr, int *uodr)
+{
+ int i, val, ret;
+ struct bmi270_odr_item bmi270_odr_item;
+
+ switch (chan_type) {
+ case IIO_ACCEL:
+ ret = regmap_read(data->regmap, BMI270_ACC_CONF_REG, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(BMI270_ACC_CONF_ODR_MSK, val);
+ bmi270_odr_item = bmi270_odr_table[BMI270_ACCEL];
+ break;
+ case IIO_ANGL_VEL:
+ ret = regmap_read(data->regmap, BMI270_GYR_CONF_REG, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(BMI270_GYR_CONF_ODR_MSK, val);
+ bmi270_odr_item = bmi270_odr_table[BMI270_GYRO];
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ for (i = 0; i < bmi270_odr_item.num; i++) {
+ if (val != bmi270_odr_item.vals[i])
+ continue;
+
+ *odr = bmi270_odr_item.tbl[i].odr;
+ *uodr = bmi270_odr_item.tbl[i].uodr;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
static irqreturn_t bmi270_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
@@ -161,6 +427,68 @@ static int bmi270_read_raw(struct iio_dev *indio_dev,
return ret;

return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ ret = bmi270_get_scale(bmi270_device, chan->type, val2);
+ return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = bmi270_get_odr(bmi270_device, chan->type, val, val2);
+ return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int bmi270_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct bmi270_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ return bmi270_set_scale(data, chan->type, val2);
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return bmi270_set_odr(data, chan->type, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int bmi270_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ switch (chan->type) {
+ case IIO_ANGL_VEL:
+ *vals = (const int *)bmi270_gyro_scale;
+ *length = ARRAY_SIZE(bmi270_gyro_scale) * 2;
+ return IIO_AVAIL_LIST;
+ case IIO_ACCEL:
+ *vals = (const int *)bmi270_accel_scale;
+ *length = ARRAY_SIZE(bmi270_accel_scale) * 2;
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ switch (chan->type) {
+ case IIO_ANGL_VEL:
+ *vals = (const int *)bmi270_gyro_odr;
+ *length = ARRAY_SIZE(bmi270_gyro_odr) * 2;
+ return IIO_AVAIL_LIST;
+ case IIO_ACCEL:
+ *vals = (const int *)bmi270_accel_odr;
+ *length = ARRAY_SIZE(bmi270_accel_odr) * 2;
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
default:
return -EINVAL;
}
@@ -168,6 +496,8 @@ static int bmi270_read_raw(struct iio_dev *indio_dev,

static const struct iio_info bmi270_info = {
.read_raw = bmi270_read_raw,
+ .write_raw = bmi270_write_raw,
+ .read_avail = bmi270_read_avail,
};

#define BMI270_ACCEL_CHANNEL(_axis) { \
@@ -175,6 +505,11 @@ static const struct iio_info bmi270_info = {
.modified = 1, \
.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), \
+ .info_mask_shared_by_type_available = \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.scan_index = BMI270_SCAN_ACCEL_##_axis, \
.scan_type = { \
.sign = 's', \
@@ -189,6 +524,11 @@ static const struct iio_info bmi270_info = {
.modified = 1, \
.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), \
+ .info_mask_shared_by_type_available = \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.scan_index = BMI270_SCAN_GYRO_##_axis, \
.scan_type = { \
.sign = 's', \
--
2.47.0