From: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Date: Mon, 30 Jun 2025 19:47:31 +0000 (+0200)
Subject: iio: imu: inv_icm42600: add wakeup functionality for Wake-on-Motion
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7586eb9b67995b3d6824a886783dab5e80b7e8d2;p=thirdparty%2Fkernel%2Fstable.git

iio: imu: inv_icm42600: add wakeup functionality for Wake-on-Motion

When Wake-on-Motion is on, enable system wakeup and keep the chip on
for waking up the system with an interrupt.

Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Link: https://patch.msgid.link/20250630-losd-3-inv-icm42600-add-wom-support-v6-3-5bb0c84800d9@tdk.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---

diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600.h b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
index 6af96df9f0ed..1430ab4f1dea 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600.h
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600.h
@@ -151,6 +151,7 @@ struct inv_icm42600_apex {
  *  @map:		regmap pointer.
  *  @vdd_supply:	VDD voltage regulator for the chip.
  *  @vddio_supply:	I/O voltage regulator for the chip.
+ *  @irq:		chip irq, required to enable/disable and set wakeup
  *  @orientation:	sensor chip orientation relative to main hardware.
  *  @conf:		chip sensors configurations.
  *  @suspended:		suspended sensors configuration.
@@ -168,6 +169,7 @@ struct inv_icm42600_state {
 	struct regmap *map;
 	struct regulator *vdd_supply;
 	struct regulator *vddio_supply;
+	int irq;
 	struct iio_mount_matrix orientation;
 	struct inv_icm42600_conf conf;
 	struct inv_icm42600_suspended suspended;
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
index c52d77cab040..7a28051330b7 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_accel.c
@@ -1206,6 +1206,11 @@ struct iio_dev *inv_icm42600_accel_init(struct inv_icm42600_state *st)
 	if (ret)
 		return ERR_PTR(ret);
 
+	/* accel events are wakeup capable */
+	ret = devm_device_init_wakeup(&indio_dev->dev);
+	if (ret)
+		return ERR_PTR(ret);
+
 	return indio_dev;
 }
 
diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
index 283483ed82ff..a4d42e7e2180 100644
--- a/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
+++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_core.c
@@ -765,6 +765,7 @@ int inv_icm42600_core_probe(struct regmap *regmap, int chip,
 	mutex_init(&st->lock);
 	st->chip = chip;
 	st->map = regmap;
+	st->irq = irq;
 
 	ret = iio_read_mount_matrix(dev, &st->orientation);
 	if (ret) {
@@ -843,6 +844,9 @@ EXPORT_SYMBOL_NS_GPL(inv_icm42600_core_probe, "IIO_ICM42600");
 static int inv_icm42600_suspend(struct device *dev)
 {
 	struct inv_icm42600_state *st = dev_get_drvdata(dev);
+	struct device *accel_dev;
+	bool wakeup;
+	int accel_conf;
 	int ret;
 
 	mutex_lock(&st->lock);
@@ -863,20 +867,32 @@ static int inv_icm42600_suspend(struct device *dev)
 			goto out_unlock;
 	}
 
-	/* disable APEX features */
-	if (st->apex.wom.enable) {
-		ret = inv_icm42600_disable_wom(st);
-		if (ret)
-			goto out_unlock;
+	/* keep chip on and wake-up capable if APEX and wakeup on */
+	accel_dev = &st->indio_accel->dev;
+	wakeup = st->apex.on && device_may_wakeup(accel_dev);
+	if (wakeup) {
+		/* keep accel on and setup irq for wakeup */
+		accel_conf = st->conf.accel.mode;
+		enable_irq_wake(st->irq);
+		disable_irq(st->irq);
+	} else {
+		/* disable APEX features and accel if wakeup disabled */
+		if (st->apex.wom.enable) {
+			ret = inv_icm42600_disable_wom(st);
+			if (ret)
+				goto out_unlock;
+		}
+		accel_conf = INV_ICM42600_SENSOR_MODE_OFF;
 	}
 
 	ret = inv_icm42600_set_pwr_mgmt0(st, INV_ICM42600_SENSOR_MODE_OFF,
-					 INV_ICM42600_SENSOR_MODE_OFF, false,
-					 NULL);
+					 accel_conf, false, NULL);
 	if (ret)
 		goto out_unlock;
 
-	regulator_disable(st->vddio_supply);
+	/* disable vddio regulator if chip is sleeping */
+	if (!wakeup)
+		regulator_disable(st->vddio_supply);
 
 out_unlock:
 	mutex_unlock(&st->lock);
@@ -892,13 +908,24 @@ static int inv_icm42600_resume(struct device *dev)
 	struct inv_icm42600_state *st = dev_get_drvdata(dev);
 	struct inv_icm42600_sensor_state *gyro_st = iio_priv(st->indio_gyro);
 	struct inv_icm42600_sensor_state *accel_st = iio_priv(st->indio_accel);
+	struct device *accel_dev;
+	bool wakeup;
 	int ret;
 
 	mutex_lock(&st->lock);
 
-	ret = inv_icm42600_enable_regulator_vddio(st);
-	if (ret)
-		goto out_unlock;
+	/* check wakeup capability */
+	accel_dev = &st->indio_accel->dev;
+	wakeup = st->apex.on && device_may_wakeup(accel_dev);
+	/* restore irq state or vddio if cut off */
+	if (wakeup) {
+		enable_irq(st->irq);
+		disable_irq_wake(st->irq);
+	} else {
+		ret = inv_icm42600_enable_regulator_vddio(st);
+		if (ret)
+			goto out_unlock;
+	}
 
 	pm_runtime_disable(dev);
 	pm_runtime_set_active(dev);
@@ -911,8 +938,8 @@ static int inv_icm42600_resume(struct device *dev)
 	if (ret)
 		goto out_unlock;
 
-	/* restore APEX features */
-	if (st->apex.wom.enable) {
+	/* restore APEX features if disabled */
+	if (!wakeup && st->apex.wom.enable) {
 		ret = inv_icm42600_enable_wom(st);
 		if (ret)
 			goto out_unlock;