// 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/mod_devicetable.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/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_command *msg = sensorhub->msg;
struct cros_ec_dev *ec = sensorhub->ec;
int ret, i;
char *name;
msg->version = 1;
msg->insize = sizeof(struct ec_response_motion_sense);
msg->outsize = sizeof(struct ec_params_motion_sense);
for (i = 0; i < sensorhub->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 (sensorhub->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",
sensorhub->resp->info.type);
continue;
}
ret = cros_ec_sensorhub_allocate_sensor(dev, name, i);
if (ret)
return ret;
sensor_type[sensorhub->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)
return ret;
}
return 0;
}
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);
struct cros_ec_sensorhub *data;
struct cros_ec_command *msg;
int ret, i, sensor_num;
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;
mutex_init(&data->cmd_lock);
data->dev = dev;
data->ec = ec;
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)) {
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;
}
data->sensor_num = sensor_num;
/*
* Prepare the ring handler before enumering the
* sensors.
*/
if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {
ret = cros_ec_sensorhub_ring_allocate(data);
if (ret)
return ret;
}
/* Enumerate the sensors.*/
ret = cros_ec_sensorhub_register(dev, data);
if (ret)
return ret;
/*
* When 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);
if (ret)
return ret;
/*
* The msg and its data is not under the control of the
* ring handler.
*/
return devm_add_action_or_reset(dev,
cros_ec_sensorhub_ring_remove,
data);
}
} else {
/*
* If the device has sensors but does not claim to
* be a sensor hub, we are in legacy mode.
*/
data->sensor_num = 2;
for (i = 0; i < data->sensor_num; i++) {
ret = cros_ec_sensorhub_allocate_sensor(dev,
"cros-ec-accel-legacy", i);
if (ret)
return ret;
}
}
return 0;
}
#ifdef CONFIG_PM_SLEEP
/*
* 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 cros_ec_sensorhub_suspend(struct device *dev)
{
struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev);
struct cros_ec_dev *ec = sensorhub->ec;
if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
return cros_ec_sensorhub_ring_fifo_enable(sensorhub, false);
return 0;
}
static int cros_ec_sensorhub_resume(struct device *dev)
{
struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev);
struct cros_ec_dev *ec = sensorhub->ec;
if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))
return cros_ec_sensorhub_ring_fifo_enable(sensorhub, true);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(cros_ec_sensorhub_pm_ops,
cros_ec_sensorhub_suspend,
cros_ec_sensorhub_resume);
static const struct platform_device_id cros_ec_sensorhub_id[] = {
{ DRV_NAME, 0 },
{}
};
MODULE_DEVICE_TABLE(platform, cros_ec_sensorhub_id);
static struct platform_driver cros_ec_sensorhub_driver = {
.driver = {
.name = DRV_NAME,
.pm = &cros_ec_sensorhub_pm_ops,
},
.probe = cros_ec_sensorhub_probe,
.id_table = cros_ec_sensorhub_id,
};
module_platform_driver(cros_ec_sensorhub_driver);
MODULE_AUTHOR("Gwendal Grignou <[email protected]>");
MODULE_DESCRIPTION("ChromeOS EC MEMS Sensor Hub Driver");
MODULE_LICENSE("GPL");
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