Merge tag 'tag-ib-chrome-mfd-iio-input-5.5' into chrome-platform-5.5

IB between mfd, iio, input and chrome platform for cros-ec-sensorhub

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

17 files changed, 636 insertions, 421 deletions

diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
index fcc3f999e482..65f85faf6f31 100644
--- a/drivers/iio/accel/cros_ec_accel_legacy.c
+++ b/drivers/iio/accel/cros_ec_accel_legacy.c
@@ -163,16 +163,10 @@ static const struct iio_chan_spec cros_ec_accel_legacy_channels[] = {
 static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
 	struct iio_dev *indio_dev;
 	struct cros_ec_sensors_core_state *state;
 	int ret;
 
-	if (!ec || !ec->ec_dev) {
-		dev_warn(&pdev->dev, "No EC device found.\n");
-		return -EINVAL;
-	}
-
 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
 	if (!indio_dev)
 		return -ENOMEM;
diff --git a/drivers/iio/common/cros_ec_sensors/Kconfig b/drivers/iio/common/cros_ec_sensors/Kconfig
index cdbb29cfb907..fefad9572790 100644
--- a/drivers/iio/common/cros_ec_sensors/Kconfig
+++ b/drivers/iio/common/cros_ec_sensors/Kconfig
@@ -4,7 +4,7 @@
 #
 config IIO_CROS_EC_SENSORS_CORE
 	tristate "ChromeOS EC Sensors Core"
-	depends on SYSFS && CROS_EC
+	depends on SYSFS && CROS_EC_SENSORHUB
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	help
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
index a6987726eeb8..7dce04473467 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
@@ -222,17 +222,11 @@ static const struct iio_info ec_sensors_info = {
 static int cros_ec_sensors_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
 	struct iio_dev *indio_dev;
 	struct cros_ec_sensors_state *state;
 	struct iio_chan_spec *channel;
 	int ret, i;
 
-	if (!ec_dev || !ec_dev->ec_dev) {
-		dev_warn(&pdev->dev, "No CROS EC device found.\n");
-		return -EINVAL;
-	}
-
 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*state));
 	if (!indio_dev)
 		return -ENOMEM;
diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
index d2609e6feda4..81a7f692de2f 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c
@@ -18,6 +18,7 @@
 #include <linux/slab.h>
 #include <linux/platform_data/cros_ec_commands.h>
 #include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_data/cros_ec_sensorhub.h>
 #include <linux/platform_device.h>
 
 static char *cros_ec_loc[] = {
@@ -88,7 +89,8 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
 {
 	struct device *dev = &pdev->dev;
 	struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
-	struct cros_ec_dev *ec = dev_get_drvdata(pdev->dev.parent);
+	struct cros_ec_sensorhub *sensor_hub = dev_get_drvdata(dev->parent);
+	struct cros_ec_dev *ec = sensor_hub->ec;
 	struct cros_ec_sensor_platform *sensor_platform = dev_get_platdata(dev);
 	u32 ver_mask;
 	int ret, i;
diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c
index c5263b563fc1..d85a391e50c5 100644
--- a/drivers/iio/light/cros_ec_light_prox.c
+++ b/drivers/iio/light/cros_ec_light_prox.c
@@ -169,17 +169,11 @@ static const struct iio_info cros_ec_light_prox_info = {
 static int cros_ec_light_prox_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
 	struct iio_dev *indio_dev;
 	struct cros_ec_light_prox_state *state;
 	struct iio_chan_spec *channel;
 	int ret;
 
-	if (!ec_dev || !ec_dev->ec_dev) {
-		dev_warn(dev, "No CROS EC device found.\n");
-		return -EINVAL;
-	}
-
 	indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
 	if (!indio_dev)
 		return -ENOMEM;
diff --git a/drivers/input/keyboard/cros_ec_keyb.c b/drivers/input/keyboard/cros_ec_keyb.c
index 8d4d9786cc74..2b71c5a51f90 100644
--- a/drivers/input/keyboard/cros_ec_keyb.c
+++ b/drivers/input/keyboard/cros_ec_keyb.c
@@ -226,8 +226,6 @@ static int cros_ec_keyb_work(struct notifier_block *nb,
 {
 	struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
 						  notifier);
-	uint8_t mkbp_event_type = ckdev->ec->event_data.event_type &
-				  EC_MKBP_EVENT_TYPE_MASK;
 	u32 val;
 	unsigned int ev_type;
 
@@ -239,7 +237,7 @@ static int cros_ec_keyb_work(struct notifier_block *nb,
 	if (queued_during_suspend && !device_may_wakeup(ckdev->dev))
 		return NOTIFY_OK;
 
-	switch (mkbp_event_type) {
+	switch (ckdev->ec->event_data.event_type) {
 	case EC_MKBP_EVENT_KEY_MATRIX:
 		pm_wakeup_event(ckdev->dev, 0);
 
@@ -266,7 +264,7 @@ static int cros_ec_keyb_work(struct notifier_block *nb,
 	case EC_MKBP_EVENT_SWITCH:
 		pm_wakeup_event(ckdev->dev, 0);
 
-		if (mkbp_event_type == EC_MKBP_EVENT_BUTTON) {
+		if (ckdev->ec->event_data.event_type == EC_MKBP_EVENT_BUTTON) {
 			val = get_unaligned_le32(
 					&ckdev->ec->event_data.data.buttons);
 			ev_type = EV_KEY;
diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c
index 6e6dfd6c1871..c4b977a5dd96 100644
--- a/drivers/mfd/cros_ec_dev.c
+++ b/drivers/mfd/cros_ec_dev.c
@@ -78,6 +78,10 @@ static const struct mfd_cell cros_ec_rtc_cells[] = {
 	{ .name = "cros-ec-rtc", },
 };
 
+static const struct mfd_cell cros_ec_sensorhub_cells[] = {
+	{ .name = "cros-ec-sensorhub", },
+};
+
 static const struct mfd_cell cros_usbpd_charger_cells[] = {
 	{ .name = "cros-usbpd-charger", },
 	{ .name = "cros-usbpd-logger", },
@@ -112,229 +116,11 @@ static const struct mfd_cell cros_ec_vbc_cells[] = {
 	{ .name = "cros-ec-vbc", }
 };
 
-static int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
-{
-	struct cros_ec_command *msg;
-	int ret;
-
-	if (ec->features[0] == -1U && ec->features[1] == -1U) {
-		/* features bitmap not read yet */
-		msg = kzalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);
-		if (!msg)
-			return -ENOMEM;
-
-		msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;
-		msg->insize = sizeof(ec->features);
-
-		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
-		if (ret < 0) {
-			dev_warn(ec->dev, "cannot get EC features: %d/%d\n",
-				 ret, msg->result);
-			memset(ec->features, 0, sizeof(ec->features));
-		} else {
-			memcpy(ec->features, msg->data, sizeof(ec->features));
-		}
-
-		dev_dbg(ec->dev, "EC features %08x %08x\n",
-			ec->features[0], ec->features[1]);
-
-		kfree(msg);
-	}
-
-	return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature);
-}
-
 static void cros_ec_class_release(struct device *dev)
 {
 	kfree(to_cros_ec_dev(dev));
 }
 
-static void cros_ec_sensors_register(struct cros_ec_dev *ec)
-{
-	/*
-	 * Issue a command to get the number of sensor reported.
-	 * Build an array of sensors driver and register them all.
-	 */
-	int ret, i, id, sensor_num;
-	struct mfd_cell *sensor_cells;
-	struct cros_ec_sensor_platform *sensor_platforms;
-	int sensor_type[MOTIONSENSE_TYPE_MAX];
-	struct ec_params_motion_sense *params;
-	struct ec_response_motion_sense *resp;
-	struct cros_ec_command *msg;
-
-	msg = kzalloc(sizeof(struct cros_ec_command) +
-		      max(sizeof(*params), sizeof(*resp)), GFP_KERNEL);
-	if (msg == NULL)
-		return;
-
-	msg->version = 2;
-	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
-	msg->outsize = sizeof(*params);
-	msg->insize = sizeof(*resp);
-
-	params = (struct ec_params_motion_sense *)msg->data;
-	params->cmd = MOTIONSENSE_CMD_DUMP;
-
-	ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
-	if (ret < 0) {
-		dev_warn(ec->dev, "cannot get EC sensor information: %d/%d\n",
-			 ret, msg->result);
-		goto error;
-	}
-
-	resp = (struct ec_response_motion_sense *)msg->data;
-	sensor_num = resp->dump.sensor_count;
-	/*
-	 * Allocate 2 extra sensors if lid angle sensor and/or FIFO are needed.
-	 */
-	sensor_cells = kcalloc(sensor_num + 2, sizeof(struct mfd_cell),
-			       GFP_KERNEL);
-	if (sensor_cells == NULL)
-		goto error;
-
-	sensor_platforms = kcalloc(sensor_num,
-				   sizeof(struct cros_ec_sensor_platform),
-				   GFP_KERNEL);
-	if (sensor_platforms == NULL)
-		goto error_platforms;
-
-	memset(sensor_type, 0, sizeof(sensor_type));
-	id = 0;
-	for (i = 0; i < sensor_num; i++) {
-		params->cmd = MOTIONSENSE_CMD_INFO;
-		params->info.sensor_num = i;
-		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
-		if (ret < 0) {
-			dev_warn(ec->dev, "no info for EC sensor %d : %d/%d\n",
-				 i, ret, msg->result);
-			continue;
-		}
-		switch (resp->info.type) {
-		case MOTIONSENSE_TYPE_ACCEL:
-			sensor_cells[id].name = "cros-ec-accel";
-			break;
-		case MOTIONSENSE_TYPE_BARO:
-			sensor_cells[id].name = "cros-ec-baro";
-			break;
-		case MOTIONSENSE_TYPE_GYRO:
-			sensor_cells[id].name = "cros-ec-gyro";
-			break;
-		case MOTIONSENSE_TYPE_MAG:
-			sensor_cells[id].name = "cros-ec-mag";
-			break;
-		case MOTIONSENSE_TYPE_PROX:
-			sensor_cells[id].name = "cros-ec-prox";
-			break;
-		case MOTIONSENSE_TYPE_LIGHT:
-			sensor_cells[id].name = "cros-ec-light";
-			break;
-		case MOTIONSENSE_TYPE_ACTIVITY:
-			sensor_cells[id].name = "cros-ec-activity";
-			break;
-		default:
-			dev_warn(ec->dev, "unknown type %d\n", resp->info.type);
-			continue;
-		}
-		sensor_platforms[id].sensor_num = i;
-		sensor_cells[id].id = sensor_type[resp->info.type];
-		sensor_cells[id].platform_data = &sensor_platforms[id];
-		sensor_cells[id].pdata_size =
-			sizeof(struct cros_ec_sensor_platform);
-
-		sensor_type[resp->info.type]++;
-		id++;
-	}
-
-	if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2)
-		ec->has_kb_wake_angle = true;
-
-	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
-		sensor_cells[id].name = "cros-ec-ring";
-		id++;
-	}
-	if (cros_ec_check_features(ec,
-				EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {
-		sensor_cells[id].name = "cros-ec-lid-angle";
-		id++;
-	}
-
-	ret = mfd_add_devices(ec->dev, 0, sensor_cells, id,
-			      NULL, 0, NULL);
-	if (ret)
-		dev_err(ec->dev, "failed to add EC sensors\n");
-
-	kfree(sensor_platforms);
-error_platforms:
-	kfree(sensor_cells);
-error:
-	kfree(msg);
-}
-
-static struct cros_ec_sensor_platform sensor_platforms[] = {
-	{ .sensor_num = 0 },
-	{ .sensor_num = 1 }
-};
-
-static const struct mfd_cell cros_ec_accel_legacy_cells[] = {
-	{
-		.name = "cros-ec-accel-legacy",
-		.platform_data = &sensor_platforms[0],
-		.pdata_size = sizeof(struct cros_ec_sensor_platform),
-	},
-	{
-		.name = "cros-ec-accel-legacy",
-		.platform_data = &sensor_platforms[1],
-		.pdata_size = sizeof(struct cros_ec_sensor_platform),
-	}
-};
-
-static void cros_ec_accel_legacy_register(struct cros_ec_dev *ec)
-{
-	struct cros_ec_device *ec_dev = ec->ec_dev;
-	u8 status;
-	int ret;
-
-	/*
-	 * ECs that need legacy support are the main EC, directly connected to
-	 * the AP.
-	 */
-	if (ec->cmd_offset != 0)
-		return;
-
-	/*
-	 * Check if EC supports direct memory reads and if EC has
-	 * accelerometers.
-	 */
-	if (ec_dev->cmd_readmem) {
-		ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS, 1,
-					  &status);
-		if (ret < 0) {
-			dev_warn(ec->dev, "EC direct read error.\n");
-			return;
-		}
-
-		/* Check if EC has accelerometers. */
-		if (!(status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
-			dev_info(ec->dev, "EC does not have accelerometers.\n");
-			return;
-		}
-	}
-
-	/*
-	 * The device may still support accelerometers:
-	 * it would be an older ARM based device that do not suppor the
-	 * EC_CMD_GET_FEATURES command.
-	 *
-	 * Register 2 accelerometers, we will fail in the IIO driver if there
-	 * are no sensors.
-	 */
-	ret = mfd_add_hotplug_devices(ec->dev, cros_ec_accel_legacy_cells,
-				      ARRAY_SIZE(cros_ec_accel_legacy_cells));
-	if (ret)
-		dev_err(ec_dev->dev, "failed to add EC sensors\n");
-}
-
 static int ec_device_probe(struct platform_device *pdev)
 {
 	int retval = -ENOMEM;
@@ -390,11 +176,14 @@ static int ec_device_probe(struct platform_device *pdev)
 		goto failed;
 
 	/* check whether this EC is a sensor hub. */
-	if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE))
-		cros_ec_sensors_register(ec);
-	else
-		/* Workaroud for older EC firmware */
-		cros_ec_accel_legacy_register(ec);
+	if (cros_ec_get_sensor_count(ec) > 0) {
+		retval = mfd_add_hotplug_devices(ec->dev,
+				cros_ec_sensorhub_cells,
+				ARRAY_SIZE(cros_ec_sensorhub_cells));
+		if (retval)
+			dev_err(ec->dev, "failed to add %s subdevice: %d\n",
+				cros_ec_sensorhub_cells->name, retval);
+	}
 
 	/*
 	 * The following subdevices can be detected by sending the
diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index b66cc7182287..38f4b98a98b2 100644
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -190,6 +190,18 @@ config CROS_EC_DEBUGFS
 	  To compile this driver as a module, choose M here: the
 	  module will be called cros_ec_debugfs.
 
+config CROS_EC_SENSORHUB
+	tristate "ChromeOS EC MEMS Sensor Hub"
+	depends on CROS_EC
+	help
+	  Allow loading IIO sensors. This driver is loaded by MFD and will in
+	  turn query the EC and register the sensors.
+	  It also spreads the sensor data coming from the EC to the IIO sensor
+	  object.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cros_ec_sensorhub.
+
 config CROS_EC_SYSFS
 	tristate "ChromeOS EC control and information through sysfs"
 	depends on MFD_CROS_EC_DEV && SYSFS
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 477ec3d1d1c9..aacd5920d8a1 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_CROS_EC_CHARDEV)		+= cros_ec_chardev.o
 obj-$(CONFIG_CROS_EC_LIGHTBAR)		+= cros_ec_lightbar.o
 obj-$(CONFIG_CROS_EC_VBC)		+= cros_ec_vbc.o
 obj-$(CONFIG_CROS_EC_DEBUGFS)		+= cros_ec_debugfs.o
+obj-$(CONFIG_CROS_EC_SENSORHUB)		+= cros_ec_sensorhub.o
 obj-$(CONFIG_CROS_EC_SYSFS)		+= cros_ec_sysfs.o
 obj-$(CONFIG_CROS_USBPD_LOGGER)		+= cros_usbpd_logger.o
 
diff --git a/drivers/platform/chrome/cros_ec.c b/drivers/platform/chrome/cros_ec.c
index fd77e6fa74c2..6d6ce86a1408 100644
--- a/drivers/platform/chrome/cros_ec.c
+++ b/drivers/platform/chrome/cros_ec.c
@@ -31,13 +31,32 @@ static struct cros_ec_platform pd_p = {
 	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX),
 };
 
-static irqreturn_t ec_irq_thread(int irq, void *data)
+static irqreturn_t ec_irq_handler(int irq, void *data)
 {
 	struct cros_ec_device *ec_dev = data;
-	bool wake_event = true;
+
+	ec_dev->last_event_time = cros_ec_get_time_ns();
+
+	return IRQ_WAKE_THREAD;
+}
+
+/**
+ * cros_ec_handle_event() - process and forward pending events on EC
+ * @ec_dev: Device with events to process.
+ *
+ * Call this function in a loop when the kernel is notified that the EC has
+ * pending events.
+ *
+ * Return: true if more events are still pending and this function should be
+ * called again.
+ */
+bool cros_ec_handle_event(struct cros_ec_device *ec_dev)
+{
+	bool wake_event;
+	bool ec_has_more_events;
 	int ret;
 
-	ret = cros_ec_get_next_event(ec_dev, &wake_event);
+	ret = cros_ec_get_next_event(ec_dev, &wake_event, &ec_has_more_events);
 
 	/*
 	 * Signal only if wake host events or any interrupt if
@@ -50,6 +69,20 @@ static irqreturn_t ec_irq_thread(int irq, void *data)
 	if (ret > 0)
 		blocking_notifier_call_chain(&ec_dev->event_notifier,
 					     0, ec_dev);
+
+	return ec_has_more_events;
+}
+EXPORT_SYMBOL(cros_ec_handle_event);
+
+static irqreturn_t ec_irq_thread(int irq, void *data)
+{
+	struct cros_ec_device *ec_dev = data;
+	bool ec_has_more_events;
+
+	do {
+		ec_has_more_events = cros_ec_handle_event(ec_dev);
+	} while (ec_has_more_events);
+
 	return IRQ_HANDLED;
 }
 
@@ -104,6 +137,15 @@ static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
 	return ret;
 }
 
+/**
+ * cros_ec_register() - Register a new ChromeOS EC, using the provided info.
+ * @ec_dev: Device to register.
+ *
+ * Before calling this, allocate a pointer to a new device and then fill
+ * in all the fields up to the --private-- marker.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_register(struct cros_ec_device *ec_dev)
 {
 	struct device *dev = ec_dev->dev;
@@ -131,10 +173,12 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
 		return err;
 	}
 
-	if (ec_dev->irq) {
-		err = devm_request_threaded_irq(dev, ec_dev->irq, NULL,
-				ec_irq_thread, IRQF_TRIGGER_LOW | IRQF_ONESHOT,
-				"chromeos-ec", ec_dev);
+	if (ec_dev->irq > 0) {
+		err = devm_request_threaded_irq(dev, ec_dev->irq,
+						ec_irq_handler,
+						ec_irq_thread,
+						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+						"chromeos-ec", ec_dev);
 		if (err) {
 			dev_err(dev, "Failed to request IRQ %d: %d",
 				ec_dev->irq, err);
@@ -198,6 +242,14 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
 }
 EXPORT_SYMBOL(cros_ec_register);
 
+/**
+ * cros_ec_unregister() - Remove a ChromeOS EC.
+ * @ec_dev: Device to unregister.
+ *
+ * Call this to deregister a ChromeOS EC, then clean up any private data.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_unregister(struct cros_ec_device *ec_dev)
 {
 	if (ec_dev->pd)
@@ -209,6 +261,14 @@ int cros_ec_unregister(struct cros_ec_device *ec_dev)
 EXPORT_SYMBOL(cros_ec_unregister);
 
 #ifdef CONFIG_PM_SLEEP
+/**
+ * cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
+ * @ec_dev: Device to suspend.
+ *
+ * This can be called by drivers to handle a suspend event.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_suspend(struct cros_ec_device *ec_dev)
 {
 	struct device *dev = ec_dev->dev;
@@ -238,11 +298,19 @@ EXPORT_SYMBOL(cros_ec_suspend);
 static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev)
 {
 	while (ec_dev->mkbp_event_supported &&
-	       cros_ec_get_next_event(ec_dev, NULL) > 0)
+	       cros_ec_get_next_event(ec_dev, NULL, NULL) > 0)
 		blocking_notifier_call_chain(&ec_dev->event_notifier,
 					     1, ec_dev);
 }
 
+/**
+ * cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
+ * @ec_dev: Device to resume.
+ *
+ * This can be called by drivers to handle a resume event.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_resume(struct cros_ec_device *ec_dev)
 {
 	int ret;
diff --git a/drivers/platform/chrome/cros_ec_ishtp.c b/drivers/platform/chrome/cros_ec_ishtp.c
index 25ca2c894b4d..e5996821d08b 100644
--- a/drivers/platform/chrome/cros_ec_ishtp.c
+++ b/drivers/platform/chrome/cros_ec_ishtp.c
@@ -136,11 +136,11 @@ static void ish_evt_handler(struct work_struct *work)
 	struct ishtp_cl_data *client_data =
 		container_of(work, struct ishtp_cl_data, work_ec_evt);
 	struct cros_ec_device *ec_dev = client_data->ec_dev;
+	bool ec_has_more_events;
 
-	if (cros_ec_get_next_event(ec_dev, NULL) > 0) {
-		blocking_notifier_call_chain(&ec_dev->event_notifier,
-					     0, ec_dev);
-	}
+	do {
+		ec_has_more_events = cros_ec_handle_event(ec_dev);
+	} while (ec_has_more_events);
 }
 
 /**
@@ -200,13 +200,14 @@ static int ish_send(struct ishtp_cl_data *client_data,
  * process_recv() - Received and parse incoming packet
  * @cros_ish_cl: Client instance to get stats
  * @rb_in_proc: Host interface message buffer
+ * @timestamp: Timestamp of when parent callback started
  *
  * Parse the incoming packet. If it is a response packet then it will
  * update per instance flags and wake up the caller waiting to for the
  * response. If it is an event packet then it will schedule event work.
  */
 static void process_recv(struct ishtp_cl *cros_ish_cl,
-			 struct ishtp_cl_rb *rb_in_proc)
+			 struct ishtp_cl_rb *rb_in_proc, ktime_t timestamp)
 {
 	size_t data_len = rb_in_proc->buf_idx;
 	struct ishtp_cl_data *client_data =
@@ -295,6 +296,11 @@ error_wake_up:
 		break;
 
 	case CROS_MKBP_EVENT:
+		/*
+		 * Set timestamp from beginning of function since we actually
+		 * got an incoming MKBP event
+		 */
+		client_data->ec_dev->last_event_time = timestamp;
 		/* The event system doesn't send any data in buffer */
 		schedule_work(&client_data->work_ec_evt);
 
@@ -322,10 +328,17 @@ static void ish_event_cb(struct ishtp_cl_device *cl_device)
 {
 	struct ishtp_cl_rb *rb_in_proc;
 	struct ishtp_cl	*cros_ish_cl = ishtp_get_drvdata(cl_device);
+	ktime_t timestamp;
+
+	/*
+	 * Take timestamp as close to hardware interrupt as possible for sensor
+	 * timestamps.
+	 */
+	timestamp = cros_ec_get_time_ns();
 
 	while ((rb_in_proc = ishtp_cl_rx_get_rb(cros_ish_cl)) != NULL) {
 		/* Decide what to do with received data */
-		process_recv(cros_ish_cl, rb_in_proc);
+		process_recv(cros_ish_cl, rb_in_proc, timestamp);
 	}
 }
 
diff --git a/drivers/platform/chrome/cros_ec_lpc.c b/drivers/platform/chrome/cros_ec_lpc.c
index 7d10d909435f..dccf479c6625 100644
--- a/drivers/platform/chrome/cros_ec_lpc.c
+++ b/drivers/platform/chrome/cros_ec_lpc.c
@@ -312,11 +312,20 @@ static int cros_ec_lpc_readmem(struct cros_ec_device *ec, unsigned int offset,
 static void cros_ec_lpc_acpi_notify(acpi_handle device, u32 value, void *data)
 {
 	struct cros_ec_device *ec_dev = data;
+	bool ec_has_more_events;
+	int ret;
 
-	if (ec_dev->mkbp_event_supported &&
-	    cros_ec_get_next_event(ec_dev, NULL) > 0)
-		blocking_notifier_call_chain(&ec_dev->event_notifier, 0,
-					     ec_dev);
+	ec_dev->last_event_time = cros_ec_get_time_ns();
+
+	if (ec_dev->mkbp_event_supported)
+		do {
+			ret = cros_ec_get_next_event(ec_dev, NULL,
+						     &ec_has_more_events);
+			if (ret > 0)
+				blocking_notifier_call_chain(
+						&ec_dev->event_notifier, 0,
+						ec_dev);
+		} while (ec_has_more_events);
 
 	if (value == ACPI_NOTIFY_DEVICE_WAKE)
 		pm_system_wakeup();
diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index f659f96bda12..da1b1c450433 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -117,6 +117,17 @@ static int send_command(struct cros_ec_device *ec_dev,
 	return ret;
 }
 
+/**
+ * cros_ec_prepare_tx() - Prepare an outgoing message in the output buffer.
+ * @ec_dev: Device to register.
+ * @msg: Message to write.
+ *
+ * This is intended to be used by all ChromeOS EC drivers, but at present
+ * only SPI uses it. Once LPC uses the same protocol it can start using it.
+ * I2C could use it now, with a refactor of the existing code.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
 		       struct cros_ec_command *msg)
 {
@@ -141,6 +152,16 @@ int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
 }
 EXPORT_SYMBOL(cros_ec_prepare_tx);
 
+/**
+ * cros_ec_check_result() - Check ec_msg->result.
+ * @ec_dev: EC device.
+ * @msg: Message to check.
+ *
+ * This is used by ChromeOS EC drivers to check the ec_msg->result for
+ * errors and to warn about them.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_check_result(struct cros_ec_device *ec_dev,
 			 struct cros_ec_command *msg)
 {
@@ -326,6 +347,13 @@ static int cros_ec_get_host_command_version_mask(struct cros_ec_device *ec_dev,
 	return ret;
 }
 
+/**
+ * cros_ec_query_all() -  Query the protocol version supported by the
+ *         ChromeOS EC.
+ * @ec_dev: Device to register.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_query_all(struct cros_ec_device *ec_dev)
 {
 	struct device *dev = ec_dev->dev;
@@ -428,7 +456,10 @@ int cros_ec_query_all(struct cros_ec_device *ec_dev)
 	if (ret < 0 || ver_mask == 0)
 		ec_dev->mkbp_event_supported = 0;
 	else
-		ec_dev->mkbp_event_supported = 1;
+		ec_dev->mkbp_event_supported = fls(ver_mask);
+
+	dev_dbg(ec_dev->dev, "MKBP support version %u\n",
+		ec_dev->mkbp_event_supported - 1);
 
 	/* Probe if host sleep v1 is supported for S0ix failure detection. */
 	ret = cros_ec_get_host_command_version_mask(ec_dev,
@@ -453,6 +484,16 @@ exit:
 }
 EXPORT_SYMBOL(cros_ec_query_all);
 
+/**
+ * cros_ec_cmd_xfer() - Send a command to the ChromeOS EC.
+ * @ec_dev: EC device.
+ * @msg: Message to write.
+ *
+ * Call this to send a command to the ChromeOS EC.  This should be used
+ * instead of calling the EC's cmd_xfer() callback directly.
+ *
+ * Return: 0 on success or negative error code.
+ */
 int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
 		     struct cros_ec_command *msg)
 {
@@ -500,6 +541,18 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
 }
 EXPORT_SYMBOL(cros_ec_cmd_xfer);
 
+/**
+ * cros_ec_cmd_xfer_status() - Send a command to the ChromeOS EC.
+ * @ec_dev: EC device.
+ * @msg: Message to write.
+ *
+ * This function is identical to cros_ec_cmd_xfer, except it returns success
+ * status only if both the command was transmitted successfully and the EC
+ * replied with success status. It's not necessary to check msg->result when
+ * using this function.
+ *
+ * Return: The number of bytes transferred on success or negative error code.
+ */
 int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
 			    struct cros_ec_command *msg)
 {
@@ -519,6 +572,7 @@ EXPORT_SYMBOL(cros_ec_cmd_xfer_status);
 
 static int get_next_event_xfer(struct cros_ec_device *ec_dev,
 			       struct cros_ec_command *msg,
+			       struct ec_response_get_next_event_v1 *event,
 			       int version, uint32_t size)
 {
 	int ret;
@@ -531,7 +585,7 @@ static int get_next_event_xfer(struct cros_ec_device *ec_dev,
 	ret = cros_ec_cmd_xfer(ec_dev, msg);
 	if (ret > 0) {
 		ec_dev->event_size = ret - 1;
-		memcpy(&ec_dev->event_data, msg->data, ret);
+		ec_dev->event_data = *event;
 	}
 
 	return ret;
@@ -539,30 +593,26 @@ static int get_next_event_xfer(struct cros_ec_device *ec_dev,
 
 static int get_next_event(struct cros_ec_device *ec_dev)
 {
-	u8 buffer[sizeof(struct cros_ec_command) + sizeof(ec_dev->event_data)];
-	struct cros_ec_command *msg = (struct cros_ec_command *)&buffer;
-	static int cmd_version = 1;
-	int ret;
+	struct {
+		struct cros_ec_command msg;
+		struct ec_response_get_next_event_v1 event;
+	} __packed buf;
+	struct cros_ec_command *msg = &buf.msg;
+	struct ec_response_get_next_event_v1 *event = &buf.event;
+	const int cmd_version = ec_dev->mkbp_event_supported - 1;
 
+	memset(msg, 0, sizeof(*msg));
 	if (ec_dev->suspended) {
 		dev_dbg(ec_dev->dev, "Device suspended.\n");
 		return -EHOSTDOWN;
 	}
 
-	if (cmd_version == 1) {
-		ret = get_next_event_xfer(ec_dev, msg, cmd_version,
-				sizeof(struct ec_response_get_next_event_v1));
-		if (ret < 0 || msg->result != EC_RES_INVALID_VERSION)
-			return ret;
-
-		/* Fallback to version 0 for future send attempts */
-		cmd_version = 0;
-	}
-
-	ret = get_next_event_xfer(ec_dev, msg, cmd_version,
+	if (cmd_version == 0)
+		return get_next_event_xfer(ec_dev, msg, event, 0,
 				  sizeof(struct ec_response_get_next_event));
 
-	return ret;
+	return get_next_event_xfer(ec_dev, msg, event, cmd_version,
+				sizeof(struct ec_response_get_next_event_v1));
 }
 
 static int get_keyboard_state_event(struct cros_ec_device *ec_dev)
@@ -584,27 +634,60 @@ static int get_keyboard_state_event(struct cros_ec_device *ec_dev)
 	return ec_dev->event_size;
 }
 
-int cros_ec_get_next_event(struct cros_ec_device *ec_dev, bool *wake_event)
+/**
+ * cros_ec_get_next_event() - Fetch next event from the ChromeOS EC.
+ * @ec_dev: Device to fetch event from.
+ * @wake_event: Pointer to a bool set to true upon return if the event might be
+ *              treated as a wake event. Ignored if null.
+ * @has_more_events: Pointer to bool set to true if more than one event is
+ *              pending.
+ *              Some EC will set this flag to indicate cros_ec_get_next_event()
+ *              can be called multiple times in a row.
+ *              It is an optimization to prevent issuing a EC command for
+ *              nothing or wait for another interrupt from the EC to process
+ *              the next message.
+ *              Ignored if null.
+ *
+ * Return: negative error code on errors; 0 for no data; or else number of
+ * bytes received (i.e., an event was retrieved successfully). Event types are
+ * written out to @ec_dev->event_data.event_type on success.
+ */
+int cros_ec_get_next_event(struct cros_ec_device *ec_dev,
+			   bool *wake_event,
+			   bool *has_more_events)
 {
 	u8 event_type;
 	u32 host_event;
 	int ret;
 
-	if (!ec_dev->mkbp_event_supported) {
-		ret = get_keyboard_state_event(ec_dev);
-		if (ret <= 0)
-			return ret;
+	/*
+	 * Default value for wake_event.
+	 * Wake up on keyboard event, wake up for spurious interrupt or link
+	 * error to the EC.
+	 */
+	if (wake_event)
+		*wake_event = true;
 
-		if (wake_event)
-			*wake_event = true;
+	/*
+	 * Default value for has_more_events.
+	 * EC will raise another interrupt if AP does not process all events
+	 * anyway.
+	 */
+	if (has_more_events)
+		*has_more_events = false;
 
-		return ret;
-	}
+	if (!ec_dev->mkbp_event_supported)
+		return get_keyboard_state_event(ec_dev);
 
 	ret = get_next_event(ec_dev);
 	if (ret <= 0)
 		return ret;
 
+	if (has_more_events)
+		*has_more_events = ec_dev->event_data.event_type &
+			EC_MKBP_HAS_MORE_EVENTS;
+	ec_dev->event_data.event_type &= EC_MKBP_EVENT_TYPE_MASK;
+
 	if (wake_event) {
 		event_type = ec_dev->event_data.event_type;
 		host_event = cros_ec_get_host_event(ec_dev);
@@ -619,15 +702,22 @@ int cros_ec_get_next_event(struct cros_ec_device *ec_dev, bool *wake_event)
 		else if (host_event &&
 			 !(host_event & ec_dev->host_event_wake_mask))
 			*wake_event = false;
-		/* Consider all other events as wake events. */
-		else
-			*wake_event = true;
 	}
 
 	return ret;
 }
 EXPORT_SYMBOL(cros_ec_get_next_event);
 
+/**
+ * cros_ec_get_host_event() - Return a mask of event set by the ChromeOS EC.
+ * @ec_dev: Device to fetch event from.
+ *
+ * When MKBP is supported, when the EC raises an interrupt, we collect the
+ * events raised and call the functions in the ec notifier. This function
+ * is a helper to know which events are raised.
+ *
+ * Return: 0 on error or non-zero bitmask of one or more EC_HOST_EVENT_*.
+ */
 u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev)
 {
 	u32 host_event;
@@ -647,3 +737,120 @@ u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev)
 	return host_event;
 }
 EXPORT_SYMBOL(cros_ec_get_host_event);
+
+/**
+ * cros_ec_check_features() - Test for the presence of EC features
+ *
+ * @ec: EC device, does not have to be connected directly to the AP,
+ *      can be daisy chained through another device.
+ * @feature: One of ec_feature_code bit.
+ *
+ * Call this function to test whether the ChromeOS EC supports a feature.
+ *
+ * Return: 1 if supported, 0 if not
+ */
+int cros_ec_check_features(struct cros_ec_dev *ec, int feature)
+{
+	struct cros_ec_command *msg;
+	int ret;
+
+	if (ec->features[0] == -1U && ec->features[1] == -1U) {
+		/* features bitmap not read yet */
+		msg = kzalloc(sizeof(*msg) + sizeof(ec->features), GFP_KERNEL);
+		if (!msg)
+			return -ENOMEM;
+
+		msg->command = EC_CMD_GET_FEATURES + ec->cmd_offset;
+		msg->insize = sizeof(ec->features);
+
+		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+		if (ret < 0) {
+			dev_warn(ec->dev, "cannot get EC features: %d/%d\n",
+				 ret, msg->result);
+			memset(ec->features, 0, sizeof(ec->features));
+		} else {
+			memcpy(ec->features, msg->data, sizeof(ec->features));
+		}
+
+		dev_dbg(ec->dev, "EC features %08x %08x\n",
+			ec->features[0], ec->features[1]);
+
+		kfree(msg);
+	}
+
+	return ec->features[feature / 32] & EC_FEATURE_MASK_0(feature);
+}
+EXPORT_SYMBOL_GPL(cros_ec_check_features);
+
+/**
+ * cros_ec_get_sensor_count() - Return the number of MEMS sensors supported.
+ *
+ * @ec: EC device, does not have to be connected directly to the AP,
+ *      can be daisy chained through another device.
+ * Return: < 0 in case of error.
+ */
+int cros_ec_get_sensor_count(struct cros_ec_dev *ec)
+{
+	/*
+	 * Issue a command to get the number of sensor reported.
+	 * If not supported, check for legacy mode.
+	 */
+	int ret, sensor_count;
+	struct ec_params_motion_sense *params;
+	struct ec_response_motion_sense *resp;
+	struct cros_ec_command *msg;
+	struct cros_ec_device *ec_dev = ec->ec_dev;
+	u8 status;
+
+	msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),
+		      GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	msg->version = 1;
+	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
+	msg->outsize = sizeof(*params);
+	msg->insize = sizeof(*resp);
+
+	params = (struct ec_params_motion_sense *)msg->data;
+	params->cmd = MOTIONSENSE_CMD_DUMP;
+
+	ret = cros_ec_cmd_xfer(ec->ec_dev, msg);
+	if (ret < 0) {
+		sensor_count = ret;
+	} else if (msg->result != EC_RES_SUCCESS) {
+		sensor_count = -EPROTO;
+	} else {
+		resp = (struct ec_response_motion_sense *)msg->data;
+		sensor_count = resp->dump.sensor_count;
+	}
+	kfree(msg);
+
+	/*
+	 * Check legacy mode: Let's find out if sensors are accessible
+	 * via LPC interface.
+	 */
+	if (sensor_count == -EPROTO &&
+	    ec->cmd_offset == 0 &&
+	    ec_dev->cmd_readmem) {
+		ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS,
+				1, &status);
+		if (ret >= 0 &&
+		    (status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
+			/*
+			 * We have 2 sensors, one in the lid, one in the base.
+			 */
+			sensor_count = 2;
+		} else {
+			/*
+			 * EC uses LPC interface and no sensors are presented.
+			 */
+			sensor_count = 0;
+		}
+	} else if (sensor_count == -EPROTO) {
+		/* EC responded, but does not understand DUMP command. */
+		sensor_count = 0;
+	}
+	return sensor_count;
+}
+EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count);
diff --git a/drivers/platform/chrome/cros_ec_rpmsg.c b/drivers/platform/chrome/cros_ec_rpmsg.c
index 0c3738c3244d..bd068afe43b5 100644
--- a/drivers/platform/chrome/cros_ec_rpmsg.c
+++ b/drivers/platform/chrome/cros_ec_rpmsg.c
@@ -143,22 +143,11 @@ cros_ec_rpmsg_host_event_function(struct work_struct *host_event_work)
 						      struct cros_ec_rpmsg,
 						      host_event_work);
 	struct cros_ec_device *ec_dev = dev_get_drvdata(&ec_rpmsg->rpdev->dev);
-	bool wake_event = true;
-	int ret;
-
-	ret = cros_ec_get_next_event(ec_dev, &wake_event);
-
-	/*
-	 * Signal only if wake host events or any interrupt if
-	 * cros_ec_get_next_event() returned an error (default value for
-	 * wake_event is true)
-	 */
-	if (wake_event && device_may_wakeup(ec_dev->dev))
-		pm_wakeup_event(ec_dev->dev, 0);
+	bool ec_has_more_events;
 
-	if (ret > 0)
-		blocking_notifier_call_chain(&ec_dev->event_notifier,
-					     0, ec_dev);
+	do {
+		ec_has_more_events = cros_ec_handle_event(ec_dev);
+	} while (ec_has_more_events);
 }
 
 static int cros_ec_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c
new file mode 100644
index 000000000000..04d8879689e9
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_sensorhub.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sensor HUB driver that discovers sensors behind a ChromeOS Embedded
+ * Controller.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_data/cros_ec_sensorhub.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define DRV_NAME		"cros-ec-sensorhub"
+
+static void cros_ec_sensorhub_free_sensor(void *arg)
+{
+	struct platform_device *pdev = arg;
+
+	platform_device_unregister(pdev);
+}
+
+static int cros_ec_sensorhub_allocate_sensor(struct device *parent,
+					     char *sensor_name,
+					     int sensor_num)
+{
+	struct cros_ec_sensor_platform sensor_platforms = {
+		.sensor_num = sensor_num,
+	};
+	struct platform_device *pdev;
+
+	pdev = platform_device_register_data(parent, sensor_name,
+					     PLATFORM_DEVID_AUTO,
+					     &sensor_platforms,
+					     sizeof(sensor_platforms));
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
+
+	return devm_add_action_or_reset(parent,
+					cros_ec_sensorhub_free_sensor,
+					pdev);
+}
+
+static int cros_ec_sensorhub_register(struct device *dev,
+				      struct cros_ec_sensorhub *sensorhub)
+{
+	int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 };
+	struct cros_ec_dev *ec = sensorhub->ec;
+	struct ec_params_motion_sense *params;
+	struct ec_response_motion_sense *resp;
+	struct cros_ec_command *msg;
+	int ret, i, sensor_num;
+	char *name;
+
+	sensor_num = cros_ec_get_sensor_count(ec);
+	if (sensor_num < 0) {
+		dev_err(dev,
+			"Unable to retrieve sensor information (err:%d)\n",
+			sensor_num);
+		return sensor_num;
+	}
+
+	if (sensor_num == 0) {
+		dev_err(dev, "Zero sensors reported.\n");
+		return -EINVAL;
+	}
+
+	/* Prepare a message to send INFO command to each sensor. */
+	msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),
+		      GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	msg->version = 1;
+	msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
+	msg->outsize = sizeof(*params);
+	msg->insize = sizeof(*resp);
+	params = (struct ec_params_motion_sense *)msg->data;
+	resp = (struct ec_response_motion_sense *)msg->data;
+
+	for (i = 0; i < sensor_num; i++) {
+		params->cmd = MOTIONSENSE_CMD_INFO;
+		params->info.sensor_num = i;
+
+		ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+		if (ret < 0) {
+			dev_warn(dev, "no info for EC sensor %d : %d/%d\n",
+				 i, ret, msg->result);
+			continue;
+		}
+
+		switch (resp->info.type) {
+		case MOTIONSENSE_TYPE_ACCEL:
+			name = "cros-ec-accel";
+			break;
+		case MOTIONSENSE_TYPE_BARO:
+			name = "cros-ec-baro";
+			break;
+		case MOTIONSENSE_TYPE_GYRO:
+			name = "cros-ec-gyro";
+			break;
+		case MOTIONSENSE_TYPE_MAG:
+			name = "cros-ec-mag";
+			break;
+		case MOTIONSENSE_TYPE_PROX:
+			name = "cros-ec-prox";
+			break;
+		case MOTIONSENSE_TYPE_LIGHT:
+			name = "cros-ec-light";
+			break;
+		case MOTIONSENSE_TYPE_ACTIVITY:
+			name = "cros-ec-activity";
+			break;
+		default:
+			dev_warn(dev, "unknown type %d\n", resp->info.type);
+			continue;
+		}
+
+		ret = cros_ec_sensorhub_allocate_sensor(dev, name, i);
+		if (ret)
+			goto error;
+
+		sensor_type[resp->info.type]++;
+	}
+
+	if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2)
+		ec->has_kb_wake_angle = true;
+
+	if (cros_ec_check_features(ec,
+				   EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {
+		ret = cros_ec_sensorhub_allocate_sensor(dev,
+							"cros-ec-lid-angle",
+							0);
+		if (ret)
+			goto error;
+	}
+
+	kfree(msg);
+	return 0;
+
+error:
+	kfree(msg);
+	return ret;
+}
+
+static int cros_ec_sensorhub_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cros_ec_sensorhub *data;
+	int ret;
+	int i;
+
+	data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->ec = dev_get_drvdata(dev->parent);
+	dev_set_drvdata(dev, data);
+
+	/* Check whether this EC is a sensor hub. */
+	if (cros_ec_check_features(data->ec, EC_FEATURE_MOTION_SENSE)) {
+		ret = cros_ec_sensorhub_register(dev, data);
+		if (ret)
+			return ret;
+	} else {
+		/*
+		 * If the device has sensors but does not claim to
+		 * be a sensor hub, we are in legacy mode.
+		 */
+		for (i = 0; i < 2; i++) {
+			ret = cros_ec_sensorhub_allocate_sensor(dev,
+						"cros-ec-accel-legacy", i);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static struct platform_driver cros_ec_sensorhub_driver = {
+	.driver = {
+		.name = DRV_NAME,
+	},
+	.probe = cros_ec_sensorhub_probe,
+};
+
+module_platform_driver(cros_ec_sensorhub_driver);
+
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
+MODULE_DESCRIPTION("ChromeOS EC MEMS Sensor Hub Driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h
index eab7036cda09..30098a551523 100644
--- a/include/linux/platform_data/cros_ec_proto.h
+++ b/include/linux/platform_data/cros_ec_proto.h
@@ -12,6 +12,7 @@
 #include <linux/mutex.h>
 #include <linux/notifier.h>
 
+#include <linux/mfd/cros_ec.h>
 #include <linux/platform_data/cros_ec_commands.h>
 
 #define CROS_EC_DEV_NAME	"cros_ec"
@@ -115,12 +116,16 @@ struct cros_ec_command {
  *            code.
  * @pkt_xfer: Send packet to EC and get response.
  * @lock: One transaction at a time.
- * @mkbp_event_supported: True if this EC supports the MKBP event protocol.
+ * @mkbp_event_supported: 0 if MKBP not supported. Otherwise its value is
+ *                        the maximum supported version of the MKBP host event
+ *                        command + 1.
  * @host_sleep_v1: True if this EC supports the sleep v1 command.
  * @event_notifier: Interrupt event notifier for transport devices.
  * @event_data: Raw payload transferred with the MKBP event.
  * @event_size: Size in bytes of the event data.
  * @host_event_wake_mask: Mask of host events that cause wake from suspend.
+ * @last_event_time: exact time from the hard irq when we got notified of
+ *     a new event.
  * @ec: The platform_device used by the mfd driver to interface with the
  *      main EC.
  * @pd: The platform_device used by the mfd driver to interface with the
@@ -153,7 +158,7 @@ struct cros_ec_device {
 	int (*pkt_xfer)(struct cros_ec_device *ec,
 			struct cros_ec_command *msg);
 	struct mutex lock;
-	bool mkbp_event_supported;
+	u8 mkbp_event_supported;
 	bool host_sleep_v1;
 	struct blocking_notifier_head event_notifier;
 
@@ -161,6 +166,7 @@ struct cros_ec_device {
 	int event_size;
 	u32 host_event_wake_mask;
 	u32 last_resume_result;
+	ktime_t last_event_time;
 
 	/* The platform devices used by the mfd driver */
 	struct platform_device *ec;
@@ -168,14 +174,6 @@ struct cros_ec_device {
 };
 
 /**
- * struct cros_ec_sensor_platform - ChromeOS EC sensor platform information.
- * @sensor_num: Id of the sensor, as reported by the EC.
- */
-struct cros_ec_sensor_platform {
-	u8 sensor_num;
-};
-
-/**
  * struct cros_ec_platform - ChromeOS EC platform information.
  * @ec_name: Name of EC device (e.g. 'cros-ec', 'cros-pd', ...)
  *           used in /dev/ and sysfs.
@@ -187,133 +185,51 @@ struct cros_ec_platform {
 	u16 cmd_offset;
 };
 
-/**
- * cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
- * @ec_dev: Device to suspend.
- *
- * This can be called by drivers to handle a suspend event.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_suspend(struct cros_ec_device *ec_dev);
 
-/**
- * cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
- * @ec_dev: Device to resume.
- *
- * This can be called by drivers to handle a resume event.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_resume(struct cros_ec_device *ec_dev);
 
-/**
- * cros_ec_prepare_tx() - Prepare an outgoing message in the output buffer.
- * @ec_dev: Device to register.
- * @msg: Message to write.
- *
- * This is intended to be used by all ChromeOS EC drivers, but at present
- * only SPI uses it. Once LPC uses the same protocol it can start using it.
- * I2C could use it now, with a refactor of the existing code.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
 		       struct cros_ec_command *msg);
 
-/**
- * cros_ec_check_result() - Check ec_msg->result.
- * @ec_dev: EC device.
- * @msg: Message to check.
- *
- * This is used by ChromeOS EC drivers to check the ec_msg->result for
- * errors and to warn about them.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_check_result(struct cros_ec_device *ec_dev,
 			 struct cros_ec_command *msg);
 
-/**
- * cros_ec_cmd_xfer() - Send a command to the ChromeOS EC.
- * @ec_dev: EC device.
- * @msg: Message to write.
- *
- * Call this to send a command to the ChromeOS EC.  This should be used
- * instead of calling the EC's cmd_xfer() callback directly.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
 		     struct cros_ec_command *msg);
 
-/**
- * cros_ec_cmd_xfer_status() - Send a command to the ChromeOS EC.
- * @ec_dev: EC device.
- * @msg: Message to write.
- *
- * This function is identical to cros_ec_cmd_xfer, except it returns success
- * status only if both the command was transmitted successfully and the EC
- * replied with success status. It's not necessary to check msg->result when
- * using this function.
- *
- * Return: The number of bytes transferred on success or negative error code.
- */
 int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
 			    struct cros_ec_command *msg);
 
-/**
- * cros_ec_register() - Register a new ChromeOS EC, using the provided info.
- * @ec_dev: Device to register.
- *
- * Before calling this, allocate a pointer to a new device and then fill
- * in all the fields up to the --private-- marker.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_register(struct cros_ec_device *ec_dev);
 
-/**
- * cros_ec_unregister() - Remove a ChromeOS EC.
- * @ec_dev: Device to unregister.
- *
- * Call this to deregister a ChromeOS EC, then clean up any private data.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_unregister(struct cros_ec_device *ec_dev);
 
-/**
- * cros_ec_query_all() -  Query the protocol version supported by the
- *         ChromeOS EC.
- * @ec_dev: Device to register.
- *
- * Return: 0 on success or negative error code.
- */
 int cros_ec_query_all(struct cros_ec_device *ec_dev);
 
-/**
- * cros_ec_get_next_event() - Fetch next event from the ChromeOS EC.
- * @ec_dev: Device to fetch event from.
- * @wake_event: Pointer to a bool set to true upon return if the event might be
- *              treated as a wake event. Ignored if null.
- *
- * Return: negative error code on errors; 0 for no data; or else number of
- * bytes received (i.e., an event was retrieved successfully). Event types are
- * written out to @ec_dev->event_data.event_type on success.
- */
-int cros_ec_get_next_event(struct cros_ec_device *ec_dev, bool *wake_event);
+int cros_ec_get_next_event(struct cros_ec_device *ec_dev,
+			   bool *wake_event,
+			   bool *has_more_events);
+
+u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
+
+int cros_ec_check_features(struct cros_ec_dev *ec, int feature);
+
+int cros_ec_get_sensor_count(struct cros_ec_dev *ec);
+
+bool cros_ec_handle_event(struct cros_ec_device *ec_dev);
 
 /**
- * cros_ec_get_host_event() - Return a mask of event set by the ChromeOS EC.
- * @ec_dev: Device to fetch event from.
+ * cros_ec_get_time_ns() - Return time in ns.
  *
- * When MKBP is supported, when the EC raises an interrupt, we collect the
- * events raised and call the functions in the ec notifier. This function
- * is a helper to know which events are raised.
+ * This is the function used to record the time for last_event_time in struct
+ * cros_ec_device during the hard irq.
  *
- * Return: 0 on error or non-zero bitmask of one or more EC_HOST_EVENT_*.
+ * Return: ktime_t format since boot.
  */
-u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev);
+static inline ktime_t cros_ec_get_time_ns(void)
+{
+	return ktime_get_boottime_ns();
+}
 
 #endif /* __LINUX_CROS_EC_PROTO_H */
diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h
new file mode 100644
index 000000000000..bef7ffc7fce1
--- /dev/null
+++ b/include/linux/platform_data/cros_ec_sensorhub.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Chrome OS EC MEMS Sensor Hub driver.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#ifndef __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H
+#define __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H
+
+#include <linux/platform_data/cros_ec_commands.h>
+
+/**
+ * struct cros_ec_sensor_platform - ChromeOS EC sensor platform information.
+ * @sensor_num: Id of the sensor, as reported by the EC.
+ */
+struct cros_ec_sensor_platform {
+	u8 sensor_num;
+};
+
+/**
+ * struct cros_ec_sensorhub - Sensor Hub device data.
+ *
+ * @ec: Embedded Controller where the hub is located.
+ */
+struct cros_ec_sensorhub {
+	struct cros_ec_dev *ec;
+};
+
+#endif   /* __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H */