diff options
Diffstat (limited to 'drivers/platform/chrome/cros_ec_sensorhub.c')
| -rw-r--r-- | drivers/platform/chrome/cros_ec_sensorhub.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c new file mode 100644 index 0000000000..31fb8bdaad --- /dev/null +++ b/drivers/platform/chrome/cros_ec_sensorhub.c @@ -0,0 +1,263 @@ +// 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/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 struct platform_driver cros_ec_sensorhub_driver = { + .driver = { + .name = DRV_NAME, + .pm = &cros_ec_sensorhub_pm_ops, + }, + .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"); |