iio: make invensense timestamp module generic

Rename common module to inv_sensors_timestamp, add configuration
at init (chip internal clock, acceptable jitter, ...) and update
inv_icm42600 driver integration.

Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20230606162147.79667-4-inv.git-commit@tdk.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/common/inv_sensors/Makefile

@@ -3,4 +3,4 @@
 # Makefile for TDK-InvenSense sensors module.
 #
 
-obj-$(CONFIG_IIO_INV_SENSORS_TIMESTAMP) += inv_icm42600_timestamp.o
+obj-$(CONFIG_IIO_INV_SENSORS_TIMESTAMP) += inv_sensors_timestamp.o

drivers/iio/common/inv_sensors/inv_icm42600_timestamp.c → drivers/iio/common/inv_sensors/inv_sensors_timestamp.c

@@ -8,20 +8,18 @@
 #include <linux/math64.h>
 #include <linux/module.h>
 
-#include <linux/iio/common/inv_icm42600_timestamp.h>
-
-/* internal chip period is 32kHz, 31250ns */
-#define INV_ICM42600_TIMESTAMP_PERIOD		31250
-/* allow a jitter of +/- 2% */
-#define INV_ICM42600_TIMESTAMP_JITTER		2
-/* compute min and max periods accepted */
-#define INV_ICM42600_TIMESTAMP_MIN_PERIOD(_p)		\
-	(((_p) * (100 - INV_ICM42600_TIMESTAMP_JITTER)) / 100)
-#define INV_ICM42600_TIMESTAMP_MAX_PERIOD(_p)		\
-	(((_p) * (100 + INV_ICM42600_TIMESTAMP_JITTER)) / 100)
+#include <linux/iio/common/inv_sensors_timestamp.h>
+
+/* compute jitter, min and max following jitter in per mille */
+#define INV_SENSORS_TIMESTAMP_JITTER(_val, _jitter)		\
+	(div_s64((_val) * (_jitter), 1000))
+#define INV_SENSORS_TIMESTAMP_MIN(_val, _jitter)		\
+	(((_val) * (1000 - (_jitter))) / 1000)
+#define INV_SENSORS_TIMESTAMP_MAX(_val, _jitter)		\
+	(((_val) * (1000 + (_jitter))) / 1000)
 
 /* Add a new value inside an accumulator and update the estimate value */
-static void inv_update_acc(struct inv_icm42600_timestamp_acc *acc, uint32_t val)
+static void inv_update_acc(struct inv_sensors_timestamp_acc *acc, uint32_t val)
 {
 	uint64_t sum = 0;
 	size_t i;
@@ -40,56 +38,57 @@ static void inv_update_acc(struct inv_icm42600_timestamp_acc *acc, uint32_t val)
 	acc->val = div_u64(sum, i);
 }
 
-void inv_icm42600_timestamp_init(struct inv_icm42600_timestamp *ts,
-				 uint32_t period)
+void inv_sensors_timestamp_init(struct inv_sensors_timestamp *ts,
+				const struct inv_sensors_timestamp_chip *chip)
 {
-	/* initial odr for sensor after reset is 1kHz */
-	const uint32_t default_period = 1000000;
+	memset(ts, 0, sizeof(*ts));
+
+	/* save chip parameters and compute min and max clock period */
+	ts->chip = *chip;
+	ts->min_period = INV_SENSORS_TIMESTAMP_MIN(chip->clock_period, chip->jitter);
+	ts->max_period = INV_SENSORS_TIMESTAMP_MAX(chip->clock_period, chip->jitter);
 
 	/* current multiplier and period values after reset */
-	ts->mult = default_period / INV_ICM42600_TIMESTAMP_PERIOD;
-	ts->period = default_period;
-	/* new set multiplier is the one from chip initialization */
-	ts->new_mult = period / INV_ICM42600_TIMESTAMP_PERIOD;
+	ts->mult = chip->init_period / chip->clock_period;
+	ts->period = chip->init_period;
 
 	/* use theoretical value for chip period */
-	inv_update_acc(&ts->chip_period, INV_ICM42600_TIMESTAMP_PERIOD);
+	inv_update_acc(&ts->chip_period, chip->clock_period);
 }
-EXPORT_SYMBOL_NS_GPL(inv_icm42600_timestamp_init, IIO_INV_SENSORS_TIMESTAMP);
+EXPORT_SYMBOL_NS_GPL(inv_sensors_timestamp_init, IIO_INV_SENSORS_TIMESTAMP);
 
-int inv_icm42600_timestamp_update_odr(struct inv_icm42600_timestamp *ts,
-				      uint32_t period, bool fifo)
+int inv_sensors_timestamp_update_odr(struct inv_sensors_timestamp *ts,
+				     uint32_t period, bool fifo)
 {
 	/* when FIFO is on, prevent odr change if one is already pending */
 	if (fifo && ts->new_mult != 0)
 		return -EAGAIN;
 
-	ts->new_mult = period / INV_ICM42600_TIMESTAMP_PERIOD;
+	ts->new_mult = period / ts->chip.clock_period;
 
 	return 0;
 }
-EXPORT_SYMBOL_NS_GPL(inv_icm42600_timestamp_update_odr, IIO_INV_SENSORS_TIMESTAMP);
+EXPORT_SYMBOL_NS_GPL(inv_sensors_timestamp_update_odr, IIO_INV_SENSORS_TIMESTAMP);
 
-static bool inv_validate_period(uint32_t period, uint32_t mult)
+static bool inv_validate_period(struct inv_sensors_timestamp *ts, uint32_t period, uint32_t mult)
 {
-	const uint32_t chip_period = INV_ICM42600_TIMESTAMP_PERIOD;
 	uint32_t period_min, period_max;
 
 	/* check that period is acceptable */
-	period_min = INV_ICM42600_TIMESTAMP_MIN_PERIOD(chip_period) * mult;
-	period_max = INV_ICM42600_TIMESTAMP_MAX_PERIOD(chip_period) * mult;
+	period_min = ts->min_period * mult;
+	period_max = ts->max_period * mult;
 	if (period > period_min && period < period_max)
 		return true;
 	else
 		return false;
 }
 
-static bool inv_update_chip_period(struct inv_icm42600_timestamp *ts,
-				   uint32_t mult, uint32_t period)
+static bool inv_update_chip_period(struct inv_sensors_timestamp *ts,
+				    uint32_t mult, uint32_t period)
 {
 	uint32_t new_chip_period;
 
-	if (!inv_validate_period(period, mult))
+	if (!inv_validate_period(ts, period, mult))
 		return false;
 
 	/* update chip internal period estimation */
@@ -100,7 +99,7 @@ static bool inv_update_chip_period(struct inv_icm42600_timestamp *ts,
 	return true;
 }
 
-static void inv_align_timestamp_it(struct inv_icm42600_timestamp *ts)
+static void inv_align_timestamp_it(struct inv_sensors_timestamp *ts)
 {
 	int64_t delta, jitter;
 	int64_t adjust;
@@ -109,7 +108,7 @@ static void inv_align_timestamp_it(struct inv_icm42600_timestamp *ts)
 	delta = ts->it.lo - ts->timestamp;
 
 	/* adjust timestamp while respecting jitter */
-	jitter = div_s64((int64_t)ts->period * INV_ICM42600_TIMESTAMP_JITTER, 100);
+	jitter = INV_SENSORS_TIMESTAMP_JITTER((int64_t)ts->period, ts->chip.jitter);
 	if (delta > jitter)
 		adjust = jitter;
 	else if (delta < -jitter)
@@ -120,13 +119,13 @@ static void inv_align_timestamp_it(struct inv_icm42600_timestamp *ts)
 	ts->timestamp += adjust;
 }
 
-void inv_icm42600_timestamp_interrupt(struct inv_icm42600_timestamp *ts,
+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)
 {
-	struct inv_icm42600_timestamp_interval *it;
+	struct inv_sensors_timestamp_interval *it;
 	int64_t delta, interval;
-	const uint32_t fifo_mult = fifo_period / INV_ICM42600_TIMESTAMP_PERIOD;
+	const uint32_t fifo_mult = fifo_period / ts->chip.clock_period;
 	uint32_t period = ts->period;
 	bool valid = false;
 
@@ -156,11 +155,11 @@ void inv_icm42600_timestamp_interrupt(struct inv_icm42600_timestamp *ts,
 	if (valid)
 		inv_align_timestamp_it(ts);
 }
-EXPORT_SYMBOL_NS_GPL(inv_icm42600_timestamp_interrupt, IIO_INV_SENSORS_TIMESTAMP);
+EXPORT_SYMBOL_NS_GPL(inv_sensors_timestamp_interrupt, IIO_INV_SENSORS_TIMESTAMP);
 
-void inv_icm42600_timestamp_apply_odr(struct inv_icm42600_timestamp *ts,
-				      uint32_t fifo_period, size_t fifo_nb,
-				      unsigned int fifo_no)
+void inv_sensors_timestamp_apply_odr(struct inv_sensors_timestamp *ts,
+				     uint32_t fifo_period, size_t fifo_nb,
+				     unsigned int fifo_no)
 {
 	int64_t interval;
 	uint32_t fifo_mult;
@@ -181,14 +180,14 @@ void inv_icm42600_timestamp_apply_odr(struct inv_icm42600_timestamp *ts,
 	 */
 	if (ts->timestamp != 0) {
 		/* compute measured fifo period */
-		fifo_mult = fifo_period / INV_ICM42600_TIMESTAMP_PERIOD;
+		fifo_mult = fifo_period / ts->chip.clock_period;
 		fifo_period = fifo_mult * ts->chip_period.val;
 		/* computes time interval between interrupt and this sample */
 		interval = (int64_t)(fifo_nb - fifo_no) * (int64_t)fifo_period;
 		ts->timestamp = ts->it.up - interval;
 	}
 }
-EXPORT_SYMBOL_NS_GPL(inv_icm42600_timestamp_apply_odr, IIO_INV_SENSORS_TIMESTAMP);
+EXPORT_SYMBOL_NS_GPL(inv_sensors_timestamp_apply_odr, IIO_INV_SENSORS_TIMESTAMP);
 
 MODULE_AUTHOR("InvenSense, Inc.");
 MODULE_DESCRIPTION("InvenSense sensors timestamp module");

drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c

@@ -12,7 +12,7 @@
 #include <linux/math64.h>
 
 #include <linux/iio/buffer.h>
-#include <linux/iio/common/inv_icm42600_timestamp.h>
+#include <linux/iio/common/inv_sensors_timestamp.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/kfifo_buf.h>
 
@@ -99,7 +99,7 @@ static int inv_icm42600_accel_update_scan_mode(struct iio_dev *indio_dev,
 					       const unsigned long *scan_mask)
 {
 	struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
-	struct inv_icm42600_timestamp *ts = iio_priv(indio_dev);
+	struct inv_sensors_timestamp *ts = iio_priv(indio_dev);
 	struct inv_icm42600_sensor_conf conf = INV_ICM42600_SENSOR_CONF_INIT;
 	unsigned int fifo_en = 0;
 	unsigned int sleep_temp = 0;
@@ -127,7 +127,7 @@ static int inv_icm42600_accel_update_scan_mode(struct iio_dev *indio_dev,
 	}
 
 	/* update data FIFO write */
-	inv_icm42600_timestamp_apply_odr(ts, 0, 0, 0);
+	inv_sensors_timestamp_apply_odr(ts, 0, 0, 0);
 	ret = inv_icm42600_buffer_set_fifo_en(st, fifo_en | st->fifo.en);
 	if (ret)
 		goto out_unlock;
@@ -312,7 +312,7 @@ static int inv_icm42600_accel_write_odr(struct iio_dev *indio_dev,
 					int val, int val2)
 {
 	struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
-	struct inv_icm42600_timestamp *ts = iio_priv(indio_dev);
+	struct inv_sensors_timestamp *ts = iio_priv(indio_dev);
 	struct device *dev = regmap_get_device(st->map);
 	unsigned int idx;
 	struct inv_icm42600_sensor_conf conf = INV_ICM42600_SENSOR_CONF_INIT;
@@ -331,8 +331,8 @@ static int inv_icm42600_accel_write_odr(struct iio_dev *indio_dev,
 	pm_runtime_get_sync(dev);
 	mutex_lock(&st->lock);
 
-	ret = inv_icm42600_timestamp_update_odr(ts, inv_icm42600_odr_to_period(conf.odr),
-						iio_buffer_enabled(indio_dev));
+	ret = inv_sensors_timestamp_update_odr(ts, inv_icm42600_odr_to_period(conf.odr),
+					       iio_buffer_enabled(indio_dev));
 	if (ret)
 		goto out_unlock;
 
@@ -708,7 +708,8 @@ struct iio_dev *inv_icm42600_accel_init(struct inv_icm42600_state *st)
 {
 	struct device *dev = regmap_get_device(st->map);
 	const char *name;
-	struct inv_icm42600_timestamp *ts;
+	struct inv_sensors_timestamp_chip ts_chip;
+	struct inv_sensors_timestamp *ts;
 	struct iio_dev *indio_dev;
 	int ret;
 
@@ -720,8 +721,15 @@ struct iio_dev *inv_icm42600_accel_init(struct inv_icm42600_state *st)
 	if (!indio_dev)
 		return ERR_PTR(-ENOMEM);
 
+	/*
+	 * clock period is 32kHz (31250ns)
+	 * jitter is +/- 2% (20 per mille)
+	 */
+	ts_chip.clock_period = 31250;
+	ts_chip.jitter = 20;
+	ts_chip.init_period = inv_icm42600_odr_to_period(st->conf.accel.odr);
 	ts = iio_priv(indio_dev);
-	inv_icm42600_timestamp_init(ts, inv_icm42600_odr_to_period(st->conf.accel.odr));
+	inv_sensors_timestamp_init(ts, &ts_chip);
 
 	iio_device_set_drvdata(indio_dev, st);
 	indio_dev->name = name;
@@ -746,7 +754,7 @@ struct iio_dev *inv_icm42600_accel_init(struct inv_icm42600_state *st)
 int inv_icm42600_accel_parse_fifo(struct iio_dev *indio_dev)
 {
 	struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
-	struct inv_icm42600_timestamp *ts = iio_priv(indio_dev);
+	struct inv_sensors_timestamp *ts = iio_priv(indio_dev);
 	ssize_t i, size;
 	unsigned int no;
 	const void *accel, *gyro, *timestamp;
@@ -769,15 +777,15 @@ int inv_icm42600_accel_parse_fifo(struct iio_dev *indio_dev)
 
 		/* update odr */
 		if (odr & INV_ICM42600_SENSOR_ACCEL)
-			inv_icm42600_timestamp_apply_odr(ts, st->fifo.period,
-							 st->fifo.nb.total, no);
+			inv_sensors_timestamp_apply_odr(ts, st->fifo.period,
+							st->fifo.nb.total, no);
 
 		/* buffer is copied to userspace, zeroing it to avoid any data leak */
 		memset(&buffer, 0, sizeof(buffer));
 		memcpy(&buffer.accel, accel, sizeof(buffer.accel));
 		/* convert 8 bits FIFO temperature in high resolution format */
 		buffer.temp = temp ? (*temp * 64) : 0;
-		ts_val = inv_icm42600_timestamp_pop(ts);
+		ts_val = inv_sensors_timestamp_pop(ts);
 		iio_push_to_buffers_with_timestamp(indio_dev, &buffer, ts_val);
 	}
 

drivers/iio/imu/inv_icm42600/inv_icm42600_buffer.c

@@ -11,7 +11,7 @@
 #include <linux/delay.h>
 
 #include <linux/iio/buffer.h>
-#include <linux/iio/common/inv_icm42600_timestamp.h>
+#include <linux/iio/common/inv_sensors_timestamp.h>
 #include <linux/iio/iio.h>
 
 #include "inv_icm42600.h"
@@ -276,12 +276,12 @@ static int inv_icm42600_buffer_preenable(struct iio_dev *indio_dev)
 {
 	struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
 	struct device *dev = regmap_get_device(st->map);
-	struct inv_icm42600_timestamp *ts = iio_priv(indio_dev);
+	struct inv_sensors_timestamp *ts = iio_priv(indio_dev);
 
 	pm_runtime_get_sync(dev);
 
 	mutex_lock(&st->lock);
-	inv_icm42600_timestamp_reset(ts);
+	inv_sensors_timestamp_reset(ts);
 	mutex_unlock(&st->lock);
 
 	return 0;
@@ -505,16 +505,16 @@ int inv_icm42600_buffer_fifo_read(struct inv_icm42600_state *st,
 
 int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st)
 {
-	struct inv_icm42600_timestamp *ts;
+	struct inv_sensors_timestamp *ts;
 	int ret;
 
 	if (st->fifo.nb.total == 0)
 		return 0;
 
 	/* handle gyroscope timestamp and FIFO data parsing */
 	ts = iio_priv(st->indio_gyro);
-	inv_icm42600_timestamp_interrupt(ts, st->fifo.period, st->fifo.nb.total,
-					 st->fifo.nb.gyro, st->timestamp.gyro);
+	inv_sensors_timestamp_interrupt(ts, st->fifo.period, st->fifo.nb.total,
+					st->fifo.nb.gyro, st->timestamp.gyro);
 	if (st->fifo.nb.gyro > 0) {
 		ret = inv_icm42600_gyro_parse_fifo(st->indio_gyro);
 		if (ret)
@@ -523,8 +523,8 @@ int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st)
 
 	/* handle accelerometer timestamp and FIFO data parsing */
 	ts = iio_priv(st->indio_accel);
-	inv_icm42600_timestamp_interrupt(ts, st->fifo.period, st->fifo.nb.total,
-					 st->fifo.nb.accel, st->timestamp.accel);
+	inv_sensors_timestamp_interrupt(ts, st->fifo.period, st->fifo.nb.total,
+					st->fifo.nb.accel, st->timestamp.accel);
 	if (st->fifo.nb.accel > 0) {
 		ret = inv_icm42600_accel_parse_fifo(st->indio_accel);
 		if (ret)
@@ -537,7 +537,7 @@ int inv_icm42600_buffer_fifo_parse(struct inv_icm42600_state *st)
 int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
 				     unsigned int count)
 {
-	struct inv_icm42600_timestamp *ts;
+	struct inv_sensors_timestamp *ts;
 	int64_t gyro_ts, accel_ts;
 	int ret;
 
@@ -553,19 +553,19 @@ int inv_icm42600_buffer_hwfifo_flush(struct inv_icm42600_state *st,
 
 	if (st->fifo.nb.gyro > 0) {
 		ts = iio_priv(st->indio_gyro);
-		inv_icm42600_timestamp_interrupt(ts, st->fifo.period,
-						 st->fifo.nb.total, st->fifo.nb.gyro,
-						 gyro_ts);
+		inv_sensors_timestamp_interrupt(ts, st->fifo.period,
+						st->fifo.nb.total, st->fifo.nb.gyro,
+						gyro_ts);
 		ret = inv_icm42600_gyro_parse_fifo(st->indio_gyro);
 		if (ret)
 			return ret;
 	}
 
 	if (st->fifo.nb.accel > 0) {
 		ts = iio_priv(st->indio_accel);
-		inv_icm42600_timestamp_interrupt(ts, st->fifo.period,
-						 st->fifo.nb.total, st->fifo.nb.accel,
-						 accel_ts);
+		inv_sensors_timestamp_interrupt(ts, st->fifo.period,
+						st->fifo.nb.total, st->fifo.nb.accel,
+						accel_ts);
 		ret = inv_icm42600_accel_parse_fifo(st->indio_accel);
 		if (ret)
 			return ret;

drivers/iio/imu/inv_icm42600/inv_icm42600_core.c

@@ -16,7 +16,6 @@
 #include <linux/property.h>
 #include <linux/regmap.h>
 
-#include <linux/iio/common/inv_icm42600_timestamp.h>
 #include <linux/iio/iio.h>
 
 #include "inv_icm42600.h"