[PATCH 07/13] platform: chrome: sensorhub: Add FIFO support

Gwendal Grignou
2019-09-22T17:51:57Z

cros_ec_sensorhub registers a listener and query motion sense FIFO,
spread to iio sensors registers.

To test, we can use libiio:
iiod&
iio_readdev -u ip:localhost -T 10000 -s 25 -b 16 cros-ec-gyro | od -x

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
---
drivers/iio/accel/cros_ec_accel_legacy.c | 1 +
.../common/cros_ec_sensors/cros_ec_sensors.c | 1 +
.../cros_ec_sensors/cros_ec_sensors_core.c | 13 +
drivers/iio/light/cros_ec_light_prox.c | 1 +
drivers/iio/pressure/cros_ec_baro.c | 1 +
drivers/platform/chrome/Makefile | 3 +-
drivers/platform/chrome/cros_ec_sensorhub.c | 130 ++++--
.../platform/chrome/cros_ec_sensorhub_ring.c | 374 ++++++++++++++++++
.../linux/iio/common/cros_ec_sensors_core.h | 3 +
.../linux/platform_data/cros_ec_sensorhub.h | 79 ++++
10 files changed, 569 insertions(+), 37 deletions(-)
create mode 100644 drivers/platform/chrome/cros_ec_sensorhub_ring.c

diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
index c9af6fa0670d..591c0d962c44 100644
--- a/drivers/iio/accel/cros_ec_accel_legacy.c
+++ b/drivers/iio/accel/cros_ec_accel_legacy.c
@@ -212,6 +212,7 @@ static struct platform_driver cros_ec_accel_platform_driver = {
.name = DRV_NAME,
},
.probe = cros_ec_accel_legacy_probe,
+ .remove = cros_ec_sensors_core_clean,
};
module_platform_driver(cros_ec_accel_platform_driver);

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 5bd6f54afc42..a88dd8deade9 100644
--- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
+++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors.c
@@ -329,6 +329,7 @@ static struct platform_driver cros_ec_sensors_platform_driver = {
.pm = &cros_ec_sensors_pm_ops,
},
.probe = cros_ec_sensors_probe,
+ .remove = cros_ec_sensors_core_clean,
.id_table = cros_ec_sensors_ids,
};
module_platform_driver(cros_ec_sensors_platform_driver);
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 81a7f692de2f..43eb1d42820e 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
@@ -160,6 +160,19 @@ int cros_ec_sensors_core_init(struct platform_device *pdev,
}
EXPORT_SYMBOL_GPL(cros_ec_sensors_core_init);

+int cros_ec_sensors_core_clean(struct platform_device *pdev)
+{
+ struct cros_ec_sensorhub *sensor_hub =
+ dev_get_drvdata(pdev->dev.parent);
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct cros_ec_sensors_core_state *st = iio_priv(indio_dev);
+ u8 sensor_num = st->param.info.sensor_num;
+
+ cros_ec_sensorhub_unregister_push_data(sensor_hub, sensor_num);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cros_ec_sensors_core_clean);
+
int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *state,
u16 opt_length)
{
diff --git a/drivers/iio/light/cros_ec_light_prox.c b/drivers/iio/light/cros_ec_light_prox.c
index 205effc1f404..c431e4d1482d 100644
--- a/drivers/iio/light/cros_ec_light_prox.c
+++ b/drivers/iio/light/cros_ec_light_prox.c
@@ -270,6 +270,7 @@ static struct platform_driver cros_ec_light_prox_platform_driver = {
.pm = &cros_ec_sensors_pm_ops,
},
.probe = cros_ec_light_prox_probe,
+ .remove = cros_ec_sensors_core_clean,
.id_table = cros_ec_light_prox_ids,
};
module_platform_driver(cros_ec_light_prox_platform_driver);
diff --git a/drivers/iio/pressure/cros_ec_baro.c b/drivers/iio/pressure/cros_ec_baro.c
index 2354302375de..2f4d6d3ab41d 100644
--- a/drivers/iio/pressure/cros_ec_baro.c
+++ b/drivers/iio/pressure/cros_ec_baro.c
@@ -201,6 +201,7 @@ static struct platform_driver cros_ec_baro_platform_driver = {
.name = "cros-ec-baro",
},
.probe = cros_ec_baro_probe,
+ .remove = cros_ec_sensors_core_clean,
.id_table = cros_ec_baro_ids,
};
module_platform_driver(cros_ec_baro_platform_driver);
diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index a164c40dc099..cb709048c003 100644
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -17,7 +17,8 @@ obj-$(CONFIG_CROS_EC_PROTO) += cros_ec_proto.o cros_ec_trace.o
obj-$(CONFIG_CROS_KBD_LED_BACKLIGHT) += cros_kbd_led_backlight.o
obj-$(CONFIG_CROS_EC_CHARDEV) += cros_ec_chardev.o
obj-$(CONFIG_CROS_EC_LIGHTBAR) += cros_ec_lightbar.o
-obj-$(CONFIG_CROS_EC_SENSORHUB) += cros_ec_sensorhub.o
+cros_ec_sensorsupport-objs := cros_ec_sensorhub_ring.o cros_ec_sensorhub.o
+obj-$(CONFIG_CROS_EC_SENSORHUB) += cros_ec_sensorsupport.o
obj-$(CONFIG_CROS_EC_VBC) += cros_ec_vbc.o
obj-$(CONFIG_CROS_EC_DEBUGFS) += cros_ec_debugfs.o
obj-$(CONFIG_CROS_EC_SYSFS) += cros_ec_sysfs.o
diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c
index 01f11ed611fb..cf93120719c4 100644
--- a/drivers/platform/chrome/cros_ec_sensorhub.c
+++ b/drivers/platform/chrome/cros_ec_sensorhub.c
@@ -26,15 +26,14 @@
#define DRV_NAME "cros-ec-sensorhub"

static int cros_ec_sensors_register(struct device *dev,
- struct cros_ec_dev *ec)
+ struct cros_ec_sensorhub *sensorhub)
{
int ret, i, id, sensor_num;
struct mfd_cell *sensor_cells;
struct cros_ec_sensor_platform *sensor_platforms;
int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 };
- struct ec_params_motion_sense *params;
- struct ec_response_motion_sense *resp;
- struct cros_ec_command *msg;
+ struct cros_ec_command *msg = sensorhub->msg;
+ struct cros_ec_dev *ec = sensorhub->ec;

sensor_num = cros_ec_get_sensor_count(ec);
if (sensor_num < 0) {
@@ -49,32 +48,17 @@ static int cros_ec_sensors_register(struct device *dev,
return -EINVAL;
}

- /*
- * Build an array of sensors driver and register them all.
- */
- msg = kzalloc(sizeof(struct cros_ec_command) +
- max(sizeof(*params), sizeof(*resp)), GFP_KERNEL);
- if (msg == NULL) {
- ret = -ENOMEM;
- goto error;
- }
-
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;
+ msg->insize = sizeof(struct ec_response_motion_sense);
+ msg->outsize = sizeof(struct ec_params_motion_sense);

/*
* Allocate 1 extra sensor if lid angle sensor is needed.
*/
sensor_cells = kcalloc(sensor_num + 1, sizeof(struct mfd_cell),
GFP_KERNEL);
- if (sensor_cells == NULL) {
- ret = -ENOMEM;
- goto error;
- }
+ if (sensor_cells == NULL)
+ return -ENOMEM;

sensor_platforms = kcalloc(sensor_num,
sizeof(struct cros_ec_sensor_platform),
@@ -86,15 +70,15 @@ static int cros_ec_sensors_register(struct device *dev,

id = 0;
for (i = 0; i < sensor_num; i++) {
- params->cmd = MOTIONSENSE_CMD_INFO;
- params->info.sensor_num = i;
+ sensorhub->params->cmd = MOTIONSENSE_CMD_INFO;
+ sensorhub->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) {
+ switch (sensorhub->resp->info.type) {
case MOTIONSENSE_TYPE_ACCEL:
sensor_cells[id].name = "cros-ec-accel";
break;
@@ -117,7 +101,8 @@ static int cros_ec_sensors_register(struct device *dev,
sensor_cells[id].name = "cros-ec-activity";
break;
default:
- dev_warn(dev, "unknown type %d\n", resp->info.type);
+ dev_warn(dev, "unknown type %d\n",
+ sensorhub->resp->info.type);
continue;
}
sensor_platforms[id].sensor_num = i;
@@ -125,7 +110,7 @@ static int cros_ec_sensors_register(struct device *dev,
sensor_cells[id].pdata_size =
sizeof(struct cros_ec_sensor_platform);

- sensor_type[resp->info.type]++;
+ sensor_type[sensorhub->resp->info.type]++;
id++;
}

@@ -142,8 +127,6 @@ static int cros_ec_sensors_register(struct device *dev,
kfree(sensor_platforms);
error_platforms:
kfree(sensor_cells);
-error:
- kfree(msg);
return ret;
}

@@ -165,41 +148,116 @@ static const struct mfd_cell cros_ec_accel_legacy_cells[] = {
}
};

-
-
static int cros_ec_sensorhub_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);
int ret;
- struct cros_ec_sensorhub *data =
- kzalloc(sizeof(struct cros_ec_sensorhub), GFP_KERNEL);
+ struct cros_ec_sensorhub *data;
+ struct cros_ec_command *msg;
+
+ msg = devm_kzalloc(dev, sizeof(struct cros_ec_command) +
+ max((u16)sizeof(struct ec_params_motion_sense),
+ ec->ec_dev->max_response), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+ msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;

+ data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL);
if (!data)
return -ENOMEM;

+ data->dev = dev;
data->ec = ec;
+
+ mutex_init(&data->cmd_lock);
+ data->msg = msg;
+ data->params = (struct ec_params_motion_sense *)msg->data;
+ data->resp = (struct ec_response_motion_sense *)msg->data;
+
dev_set_drvdata(dev, data);

/* Check whether this EC is a sensor hub. */
if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) {
- ret = cros_ec_sensors_register(dev, ec);
+ ret = cros_ec_sensors_register(dev, data);
} else {
/* Workaroud for older EC firmware */
+ ec->has_kb_wake_angle = true;
ret = mfd_add_hotplug_devices(dev,
cros_ec_accel_legacy_cells,
ARRAY_SIZE(cros_ec_accel_legacy_cells));
}
- if (ret)
+ if (ret) {
dev_err(dev, "failed to add EC sensors: error %d\n", ret);
+ return ret;
+ }
+
+ /*
+ * If the EC does not have a FIFO, the sensors will query their data
+ * themselves via sysfs or a software trigger.
+ */
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
+ ret = cros_ec_sensorhub_ring_add(data);
+ /*
+ * The msg and its data is not under the control of the ring
+ * handler.
+ */
+ }
return ret;
}

+static int cros_ec_sensorhub_remove(struct platform_device *pdev)
+{
+ struct cros_ec_sensorhub *sensorhub = platform_get_drvdata(pdev);
+ struct cros_ec_dev *ec = sensorhub->ec;
+
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
+ cros_ec_sensorhub_ring_remove(sensorhub);
+ return 0;
+}
+
+/*
+ * When the EC is suspending, we must stop sending interrupt,
+ * we may use the same interrupt line for waking up the device.
+ * Tell the EC to stop sending non-interrupt event on the iio ring.
+ */
+static int __maybe_unused cros_ec_ring_prepare(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct cros_ec_sensorhub *sensorhub = platform_get_drvdata(pdev);
+ struct cros_ec_dev *ec = sensorhub->ec;
+
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
+ return cros_ec_sensorhub_ring_fifo_toggle(sensorhub, false);
+ return 0;
+}
+
+static void __maybe_unused cros_ec_ring_complete(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct cros_ec_sensorhub *sensorhub = platform_get_drvdata(pdev);
+ struct cros_ec_dev *ec = sensorhub->ec;
+
+ if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
+ cros_ec_sensorhub_ring_fifo_toggle(sensorhub, true);
+}
+
+#if CONFIG_PM_SLEEP
+static const struct dev_pm_ops cros_ec_sensorhub_ring_pm_ops = {
+ .prepare = cros_ec_ring_prepare,
+ .complete = cros_ec_ring_complete
+};
+#else
+static const struct dev_pm_ops cros_ec_sensorhub_ring_pm_ops = { };
+#endif
+
static struct platform_driver cros_ec_sensorhub_driver = {
.driver = {
.name = DRV_NAME,
+ .pm = &cros_ec_sensorhub_ring_pm_ops,
},
.probe = cros_ec_sensorhub_probe,
+ .remove = cros_ec_sensorhub_remove,
};

module_platform_driver(cros_ec_sensorhub_driver);
diff --git a/drivers/platform/chrome/cros_ec_sensorhub_ring.c b/drivers/platform/chrome/cros_ec_sensorhub_ring.c
new file mode 100644
index 000000000000..8cd533d5542e
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_sensorhub_ring.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * cros_ec_sensorhub_ring - Driver for Chrome OS EC Sensor hub FIFO.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/iio/iio.h>
+#include <linux/kernel.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/module.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/sort.h>
+#include <linux/slab.h>
+
+
+static inline int cros_sensorhub_send_sample(
+ struct cros_ec_sensorhub *sensorhub,
+ struct cros_ec_sensors_ring_sample *sample)
+{
+ int id = sample->sensor_id;
+ cros_ec_sensorhub_push_data_cb_t cb;
+ struct iio_dev *indio_dev;
+
+ if (id > CROS_EC_SENSOR_MAX)
+ return -EINVAL;
+
+ cb = sensorhub->push_data[id].push_data_cb;
+ if (!cb)
+ return 0;
+
+ indio_dev = sensorhub->push_data[id].indio_dev;
+
+ return cb(indio_dev, sample->vector, sample->timestamp);
+}
+
+int cros_ec_sensorhub_register_push_data(
+ struct cros_ec_sensorhub *sensorhub,
+ u8 sensor_num,
+ struct iio_dev *indio_dev,
+ cros_ec_sensorhub_push_data_cb_t cb)
+{
+ if (sensor_num > CROS_EC_SENSOR_MAX)
+ return -EINVAL;
+ if (sensorhub->push_data[sensor_num].indio_dev != NULL)
+ return -EINVAL;
+
+ sensorhub->push_data[sensor_num].indio_dev = indio_dev;
+ sensorhub->push_data[sensor_num].push_data_cb = cb;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cros_ec_sensorhub_register_push_data);
+
+void cros_ec_sensorhub_unregister_push_data(
+ struct cros_ec_sensorhub *sensorhub,
+ u8 sensor_num)
+{
+ sensorhub->push_data[sensor_num].indio_dev = NULL;
+ sensorhub->push_data[sensor_num].push_data_cb = NULL;
+}
+EXPORT_SYMBOL_GPL(cros_ec_sensorhub_unregister_push_data);
+
+int cros_ec_sensorhub_ring_fifo_toggle(
+ struct cros_ec_sensorhub *sensorhub,
+ bool on)
+{
+ int ret;
+
+ mutex_lock(&sensorhub->cmd_lock);
+ sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INT_ENABLE;
+ sensorhub->params->fifo_int_enable.enable = on;
+
+ sensorhub->msg->outsize = sizeof(struct ec_params_motion_sense);
+ sensorhub->msg->insize = sizeof(struct ec_response_motion_sense);
+
+ ret = cros_ec_cmd_xfer_status(sensorhub->ec->ec_dev, sensorhub->msg);
+ /* We expect to receive a payload of 4 bytes, ignore. */
+ if (ret > 0)
+ ret = 0;
+ mutex_unlock(&sensorhub->cmd_lock);
+ return ret;
+}
+
+/*
+ * cros_ec_ring_process_event: process one EC FIFO event
+ *
+ * Process one EC event, add it in the ring if necessary.
+ *
+ * Return true if out event has been populated.
+ *
+ * fifo_info: fifo information from the EC (includes b point, EC timebase).
+ * fifo_timestamp: EC IRQ, kernel timebase (aka c)
+ * current_timestamp: calculated event timestamp, kernel timebase (aka a')
+ * in: incoming FIFO event from EC (includes a point, EC timebase)
+ * out: outgoing event to user space (includes a')
+ */
+static bool cros_ec_ring_process_event(
+ struct cros_ec_sensorhub *sensorhub,
+ const struct cros_ec_fifo_info *fifo_info,
+ const s64 fifo_timestamp,
+ s64 *current_timestamp,
+ struct ec_response_motion_sensor_data *in,
+ struct cros_ec_sensors_ring_sample *out)
+{
+ int axis;
+ /* Do not populate the filter based on asynchronous events. */
+ const int async_flags = in->flags &
+ (MOTIONSENSE_SENSOR_FLAG_ODR | MOTIONSENSE_SENSOR_FLAG_FLUSH);
+ const s64 now = cros_ec_get_time_ns();
+
+ if (in->flags & MOTIONSENSE_SENSOR_FLAG_TIMESTAMP && !async_flags) {
+ s64 a = in->timestamp;
+ s64 b = fifo_info->info.timestamp;
+ s64 c = fifo_timestamp;
+ s64 new_timestamp;
+
+ /*
+ * disable filtering since we might add more jitter
+ * if b is in a random point in time
+ */
+ new_timestamp = c - b * 1000 + a * 1000;
+ /*
+ * The timestamp can be stale if we had to use the fifo
+ * info timestamp.
+ */
+ if (new_timestamp - *current_timestamp > 0)
+ *current_timestamp = new_timestamp;
+ }
+
+ if (in->flags & MOTIONSENSE_SENSOR_FLAG_FLUSH) {
+ out->sensor_id = in->sensor_num;
+ out->timestamp = *current_timestamp;
+ out->flag = in->flags;
+ /*
+ * No other payload information provided with
+ * flush ack.
+ */
+ return true;
+ }
+ if (in->flags & MOTIONSENSE_SENSOR_FLAG_TIMESTAMP)
+ /* If we just have a timestamp, skip this entry. */
+ return false;
+
+ /* Regular sample */
+ out->sensor_id = in->sensor_num;
+ if (*current_timestamp - now > 0) {
+ /* If the timestamp is in the future. */
+ out->timestamp = now;
+ } else {
+ out->timestamp = *current_timestamp;
+ }
+ out->flag = in->flags;
+ for (axis = 0; axis < 3; axis++)
+ out->vector[axis] = in->data[axis];
+ return true;
+}
+
+/*
+ * cros_ec_sensorhub_ring_handler - the trigger handler function
+ *
+ * @sensorhub: device information.
+ *
+ * Called by the notifier, process the EC sensor FIFO queue.
+ */
+static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub)
+{
+ struct cros_ec_fifo_info *fifo_info = &sensorhub->fifo_info;
+ struct cros_ec_dev *ec = sensorhub->ec;
+ s64 fifo_timestamp, current_timestamp;
+ int i, j, number_data, ret;
+ unsigned long sensor_mask = 0;
+ struct ec_response_motion_sensor_data *in;
+ struct cros_ec_sensors_ring_sample *out, *last_out;
+
+ mutex_lock(&sensorhub->cmd_lock);
+ /* Get FIFO information */
+ fifo_timestamp = sensorhub->fifo_timestamp[NEW_TS];
+ /* Copy elements in the main fifo */
+ if (fifo_info->info.total_lost) {
+ /* Need to retrieve the number of lost vectors per sensor */
+ sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INFO;
+ sensorhub->msg->outsize = 1;
+ sensorhub->msg->insize =
+ sizeof(struct ec_response_motion_sense_fifo_info) +
+ sizeof(u16) * CROS_EC_SENSOR_MAX;
+
+ if (cros_ec_cmd_xfer_status(ec->ec_dev, sensorhub->msg) < 0) {
+ mutex_unlock(&sensorhub->cmd_lock);
+ return;
+ }
+ memcpy(fifo_info, &sensorhub->resp->fifo_info,
+ sizeof(*fifo_info));
+ fifo_timestamp = cros_ec_get_time_ns();
+ }
+ if (fifo_info->info.count > sensorhub->fifo_size ||
+ fifo_info->info.size != sensorhub->fifo_size) {
+ dev_warn(sensorhub->dev,
+ "Mismatch EC data: count %d, size %d - expected %d",
+ fifo_info->info.count, fifo_info->info.size,
+ sensorhub->fifo_size);
+ mutex_unlock(&sensorhub->cmd_lock);
+ return;
+ }
+
+ current_timestamp = sensorhub->fifo_timestamp[LAST_TS];
+ out = sensorhub->ring;
+ for (i = 0; i < fifo_info->info.count; i += number_data) {
+ sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_READ;
+ sensorhub->params->fifo_read.max_data_vector =
+ fifo_info->info.count - i;
+ sensorhub->msg->outsize =
+ sizeof(struct ec_params_motion_sense);
+ sensorhub->msg->insize =
+ sizeof(sensorhub->resp->fifo_read) +
+ sensorhub->params->fifo_read.max_data_vector *
+ sizeof(struct ec_response_motion_sensor_data);
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, sensorhub->msg);
+ if (ret < 0) {
+ dev_warn(sensorhub->dev, "Fifo error: %d\n", ret);
+ break;
+ }
+ number_data = sensorhub->resp->fifo_read.number_data;
+ if (number_data == 0) {
+ dev_dbg(sensorhub->dev, "Unexpected empty FIFO\n");
+ break;
+ } else if (number_data > fifo_info->info.count - i) {
+ dev_warn(sensorhub->dev,
+ "Invalid EC data: too many entry received: %d, expected %d",
+ number_data, fifo_info->info.count - i);
+ break;
+ } else if (out + number_data >
+ sensorhub->ring + fifo_info->info.count) {
+ dev_warn(sensorhub->dev,
+ "Too many samples: %d (%zd data) to %d entries for expected %d entries",
+ i, out - sensorhub->ring, i + number_data,
+ fifo_info->info.count);
+ break;
+ }
+ for (in = sensorhub->resp->fifo_read.data, j = 0;
+ j < number_data; j++, in++) {
+ if (cros_ec_ring_process_event(
+ sensorhub, fifo_info, fifo_timestamp,
+ &current_timestamp, in, out)) {
+ sensor_mask |= (1 << in->sensor_num);
+ out++;
+ }
+ }
+ }
+ mutex_unlock(&sensorhub->cmd_lock);
+ last_out = out;
+
+ if (out == sensorhub->ring)
+ /* Unexpected empty FIFO. */
+ goto ring_handler_end;
+
+ /*
+ * Check if current_timestamp is ahead of the last sample.
+ * Normally, the EC appends a timestamp after the last sample, but if
+ * the AP is slow to respond to the IRQ, the EC may have added new
+ * samples. Use the FIFO info timestamp as last timestamp then.
+ */
+ if ((last_out-1)->timestamp == current_timestamp)
+ current_timestamp = fifo_timestamp;
+
+ /* Warn on lost samples. */
+ for_each_set_bit(i, &sensor_mask, BITS_PER_LONG) {
+ if (fifo_info->info.total_lost) {
+ int lost = fifo_info->lost[i];
+
+ if (lost) {
+ dev_warn(sensorhub->dev,
+ "Sensor %d: lost: %d out of %d\n", i,
+ lost, fifo_info->info.total_lost);
+ }
+ }
+ }
+
+ /* push the event into the kfifo */
+ for (out = sensorhub->ring; out < last_out; out++)
+ cros_sensorhub_send_sample(sensorhub, out);
+
+ring_handler_end:
+ sensorhub->fifo_timestamp[LAST_TS] = current_timestamp;
+}
+
+static int cros_ec_sensorhub_event(struct notifier_block *nb,
+ unsigned long queued_during_suspend, void *_notify)
+{
+ struct cros_ec_sensorhub *sensorhub;
+ struct cros_ec_device *ec_dev;
+
+ sensorhub = container_of(nb, struct cros_ec_sensorhub, notifier);
+ ec_dev = sensorhub->ec->ec_dev;
+
+ if (ec_dev->event_data.event_type != EC_MKBP_EVENT_SENSOR_FIFO)
+ return NOTIFY_DONE;
+
+ if (ec_dev->event_size != sizeof(ec_dev->event_data.data.sensor_fifo)) {
+ dev_warn(ec_dev->dev, "Invalid fifo info size\n");
+ return NOTIFY_DONE;
+ }
+
+ if (queued_during_suspend)
+ return NOTIFY_OK;
+
+ sensorhub->fifo_info.info = ec_dev->event_data.data.sensor_fifo.info;
+ sensorhub->fifo_timestamp[NEW_TS] = ec_dev->last_event_time;
+ cros_ec_sensorhub_ring_handler(sensorhub);
+ return NOTIFY_OK;
+}
+
+int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensorhub)
+{
+ struct cros_ec_dev *ec = sensorhub->ec;
+ int ret;
+
+ /* Retrieve FIFO information */
+ sensorhub->msg->version = 2;
+ sensorhub->params->cmd = MOTIONSENSE_CMD_FIFO_INFO;
+ sensorhub->msg->outsize = 1;
+ sensorhub->msg->insize =
+ sizeof(struct ec_response_motion_sense_fifo_info) +
+ sizeof(u16) * CROS_EC_SENSOR_MAX;
+
+ ret = cros_ec_cmd_xfer_status(ec->ec_dev, sensorhub->msg);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Allocate the full fifo.
+ * We need to copy the whole FIFO to set timestamps properly *
+ */
+ sensorhub->fifo_size = sensorhub->resp->fifo_info.size;
+ sensorhub->ring = devm_kcalloc(sensorhub->dev, sensorhub->fifo_size,
+ sizeof(*sensorhub->ring), GFP_KERNEL);
+ if (!sensorhub->ring)
+ return -ENOMEM;
+
+ sensorhub->fifo_timestamp[LAST_TS] = cros_ec_get_time_ns();
+
+ /* register the notifier that will act as a top half interrupt. */
+ sensorhub->notifier.notifier_call = cros_ec_sensorhub_event;
+ ret = blocking_notifier_chain_register(&ec->ec_dev->event_notifier,
+ &sensorhub->notifier);
+ if (ret < 0) {
+ dev_warn(sensorhub->dev, "failed to register notifier\n");
+ return ret;
+ }
+
+ /*
+ * Start collection samples.
+ */
+ ret = cros_ec_sensorhub_ring_fifo_toggle(sensorhub, true);
+ return ret;
+}
+
+int cros_ec_sensorhub_ring_remove(struct cros_ec_sensorhub *sensorhub)
+{
+ struct cros_ec_device *ec_dev = sensorhub->ec->ec_dev;
+
+ /*
+ * Disable the ring, prevent EC interrupt to the AP for nothing.
+ */
+ cros_ec_sensorhub_ring_fifo_toggle(sensorhub, false);
+ blocking_notifier_chain_unregister(&ec_dev->event_notifier,
+ &sensorhub->notifier);
+ return 0;
+}
+
diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h
index bb331e6356a9..abef66d0e884 100644
--- a/include/linux/iio/common/cros_ec_sensors_core.h
+++ b/include/linux/iio/common/cros_ec_sensors_core.h
@@ -116,6 +116,9 @@ struct platform_device;
int cros_ec_sensors_core_init(struct platform_device *pdev,
struct iio_dev *indio_dev, bool physical_device);

+/* To remove association of physical device to cros_ec_sensorhub. */
+int cros_ec_sensors_core_clean(struct platform_device *pdev);
+
/**
* cros_ec_sensors_capture() - the trigger handler function
* @irq: the interrupt number.
diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h
index 9295eabb16f6..18cda568c58a 100644
--- a/include/linux/platform_data/cros_ec_sensorhub.h
+++ b/include/linux/platform_data/cros_ec_sensorhub.h
@@ -9,6 +9,7 @@
#ifndef __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H
#define __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H

+#include <linux/iio/iio.h>
#include <linux/platform_data/cros_ec_commands.h>

/**
@@ -19,11 +20,89 @@ struct cros_ec_sensor_platform {
u8 sensor_num;
};

+/**
+ * Callback function to send datum to specific sensors.
+ */
+typedef int (*cros_ec_sensorhub_push_data_cb_t)(
+ struct iio_dev *indio_dev,
+ s16 *data,
+ s64 timestamp);
+
+struct cros_ec_sensorhub_sensor_push_data {
+ struct iio_dev *indio_dev;
+ cros_ec_sensorhub_push_data_cb_t push_data_cb;
+};
+
+enum {
+ LAST_TS,
+ NEW_TS,
+ ALL_TS
+};
+
+#define CROS_EC_SENSOR_MAX 16
+
+struct __ec_todo_packed cros_ec_fifo_info {
+ struct ec_response_motion_sense_fifo_info info;
+ uint16_t lost[CROS_EC_SENSOR_MAX];
+};
+
+struct cros_ec_sensors_ring_sample {
+ uint8_t sensor_id;
+ uint8_t flag;
+ int16_t vector[3];
+ s64 timestamp;
+} __packed;
+
/**
* struct cros_ec_sensorhub - Sensor Hub device data.
*/
struct cros_ec_sensorhub {
+ struct device *dev;
struct cros_ec_dev *ec;
+
+ /* Structure to send FIFO requests. */
+ struct cros_ec_command *msg;
+ struct ec_params_motion_sense *params;
+ struct ec_response_motion_sense *resp;
+ struct mutex cmd_lock;
+
+ /* Notifier to kick the FIFO interrupt */
+ struct notifier_block notifier;
+
+ /* Preprocessed ring to send to kfifos */
+ struct cros_ec_sensors_ring_sample *ring;
+
+ s64 fifo_timestamp[ALL_TS];
+ struct cros_ec_fifo_info fifo_info;
+ int fifo_size;
+
+ /*
+ * Dynamic array to be able to spread datum to iio sensor objects.
+ */
+ struct cros_ec_sensorhub_sensor_push_data push_data[CROS_EC_SENSOR_MAX];
};

+/**
+ * Function to register the callback to the sensor hub.
+ * The callback cb will be used by cros_ec_sensorhub_ring to distribute events
+ * from the EC.
+ */
+int cros_ec_sensorhub_register_push_data(
+ struct cros_ec_sensorhub *sensor_hub,
+ u8 sensor_num,
+ struct iio_dev *indio_dev,
+ cros_ec_sensorhub_push_data_cb_t cb);
+void cros_ec_sensorhub_unregister_push_data(
+ struct cros_ec_sensorhub *sensor_hub,
+ u8 sensor_num);
+
+/**
+ * Add/Remove the fifo functionality if the EC supports it.
+ */
+int cros_ec_sensorhub_ring_add(struct cros_ec_sensorhub *sensor_hub);
+int cros_ec_sensorhub_ring_remove(struct cros_ec_sensorhub *sensor_hub);
+int cros_ec_sensorhub_ring_fifo_toggle(
+ struct cros_ec_sensorhub *sensorhub,
+ bool on);
+
#endif /* __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H */
--
2.23.0.351.gc4317032e6-goog