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-rw-r--r--include/linux/iio/common/inv_sensors_timestamp.h95
-rw-r--r--include/linux/iio/consumer.h37
-rw-r--r--include/linux/iio/types.h2
3 files changed, 124 insertions, 10 deletions
diff --git a/include/linux/iio/common/inv_sensors_timestamp.h b/include/linux/iio/common/inv_sensors_timestamp.h
new file mode 100644
index 000000000000..a47d304d1ba7
--- /dev/null
+++ b/include/linux/iio/common/inv_sensors_timestamp.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 Invensense, Inc.
+ */
+
+#ifndef INV_SENSORS_TIMESTAMP_H_
+#define INV_SENSORS_TIMESTAMP_H_
+
+/**
+ * struct inv_sensors_timestamp_chip - chip internal properties
+ * @clock_period: internal clock period in ns
+ * @jitter: acceptable jitter in per-mille
+ * @init_period: chip initial period at reset in ns
+ */
+struct inv_sensors_timestamp_chip {
+ uint32_t clock_period;
+ uint32_t jitter;
+ uint32_t init_period;
+};
+
+/**
+ * struct inv_sensors_timestamp_interval - timestamps interval
+ * @lo: interval lower bound
+ * @up: interval upper bound
+ */
+struct inv_sensors_timestamp_interval {
+ int64_t lo;
+ int64_t up;
+};
+
+/**
+ * struct inv_sensors_timestamp_acc - accumulator for computing an estimation
+ * @val: current estimation of the value, the mean of all values
+ * @idx: current index of the next free place in values table
+ * @values: table of all measured values, use for computing the mean
+ */
+struct inv_sensors_timestamp_acc {
+ uint32_t val;
+ size_t idx;
+ uint32_t values[32];
+};
+
+/**
+ * struct inv_sensors_timestamp - timestamp management states
+ * @chip: chip internal characteristics
+ * @min_period: minimal acceptable clock period
+ * @max_period: maximal acceptable clock period
+ * @it: interrupts interval timestamps
+ * @timestamp: store last timestamp for computing next data timestamp
+ * @mult: current internal period multiplier
+ * @new_mult: new set internal period multiplier (not yet effective)
+ * @period: measured current period of the sensor
+ * @chip_period: accumulator for computing internal chip period
+ */
+struct inv_sensors_timestamp {
+ struct inv_sensors_timestamp_chip chip;
+ uint32_t min_period;
+ uint32_t max_period;
+ struct inv_sensors_timestamp_interval it;
+ int64_t timestamp;
+ uint32_t mult;
+ uint32_t new_mult;
+ uint32_t period;
+ struct inv_sensors_timestamp_acc chip_period;
+};
+
+void inv_sensors_timestamp_init(struct inv_sensors_timestamp *ts,
+ const struct inv_sensors_timestamp_chip *chip);
+
+int inv_sensors_timestamp_update_odr(struct inv_sensors_timestamp *ts,
+ uint32_t period, bool fifo);
+
+void inv_sensors_timestamp_interrupt(struct inv_sensors_timestamp *ts,
+ uint32_t fifo_period, size_t fifo_nb,
+ size_t sensor_nb, int64_t timestamp);
+
+static inline int64_t inv_sensors_timestamp_pop(struct inv_sensors_timestamp *ts)
+{
+ ts->timestamp += ts->period;
+ return ts->timestamp;
+}
+
+void inv_sensors_timestamp_apply_odr(struct inv_sensors_timestamp *ts,
+ uint32_t fifo_period, size_t fifo_nb,
+ unsigned int fifo_no);
+
+static inline void inv_sensors_timestamp_reset(struct inv_sensors_timestamp *ts)
+{
+ const struct inv_sensors_timestamp_interval interval_init = {0LL, 0LL};
+
+ ts->it = interval_init;
+ ts->timestamp = 0;
+}
+
+#endif
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index 6802596b017c..e9910b41d48e 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -201,8 +201,9 @@ struct iio_dev
* @chan: The channel being queried.
* @val: Value read back.
*
- * Note raw reads from iio channels are in adc counts and hence
- * scale will need to be applied if standard units required.
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
*/
int iio_read_channel_raw(struct iio_channel *chan,
int *val);
@@ -212,8 +213,9 @@ int iio_read_channel_raw(struct iio_channel *chan,
* @chan: The channel being queried.
* @val: Value read back.
*
- * Note raw reads from iio channels are in adc counts and hence
- * scale will need to be applied if standard units required.
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
*
* In opposit to the normal iio_read_channel_raw this function
* returns the average of multiple reads.
@@ -281,8 +283,9 @@ int iio_read_channel_attribute(struct iio_channel *chan, int *val,
* @chan: The channel being queried.
* @val: Value being written.
*
- * Note raw writes to iio channels are in dac counts and hence
- * scale will need to be applied if standard units required.
+ * Note that for raw writes to iio channels, if the value provided is
+ * in standard units, the affect of the scale and offset must be removed
+ * as (value / scale) - offset.
*/
int iio_write_channel_raw(struct iio_channel *chan, int val);
@@ -292,12 +295,25 @@ int iio_write_channel_raw(struct iio_channel *chan, int val);
* @chan: The channel being queried.
* @val: Value read back.
*
- * Note raw reads from iio channels are in adc counts and hence
- * scale will need to be applied if standard units are required.
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
*/
int iio_read_max_channel_raw(struct iio_channel *chan, int *val);
/**
+ * iio_read_min_channel_raw() - read minimum available raw value from a given
+ * channel, i.e. the minimum possible value.
+ * @chan: The channel being queried.
+ * @val: Value read back.
+ *
+ * Note, if standard units are required, raw reads from iio channels
+ * need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
+ */
+int iio_read_min_channel_raw(struct iio_channel *chan, int *val);
+
+/**
* iio_read_avail_channel_raw() - read available raw values from a given channel
* @chan: The channel being queried.
* @vals: Available values read back.
@@ -308,8 +324,9 @@ int iio_read_max_channel_raw(struct iio_channel *chan, int *val);
* For ranges, three vals are always returned; min, step and max.
* For lists, all the possible values are enumerated.
*
- * Note raw available values from iio channels are in adc counts and
- * hence scale will need to be applied if standard units are required.
+ * Note, if standard units are required, raw available values from iio
+ * channels need the offset (default 0) and scale (default 1) to be applied
+ * as (raw + offset) * scale.
*/
int iio_read_avail_channel_raw(struct iio_channel *chan,
const int **vals, int *length);
diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
index 82faa98c719a..117bde7d6ad7 100644
--- a/include/linux/iio/types.h
+++ b/include/linux/iio/types.h
@@ -19,6 +19,8 @@ enum iio_event_info {
IIO_EV_INFO_TIMEOUT,
IIO_EV_INFO_RESET_TIMEOUT,
IIO_EV_INFO_TAP2_MIN_DELAY,
+ IIO_EV_INFO_RUNNING_PERIOD,
+ IIO_EV_INFO_RUNNING_COUNT,
};
#define IIO_VAL_INT 1