diff options
Diffstat (limited to 'drivers/platform/chrome/cros_ec_sensorhub.c')
| -rw-r--r-- | drivers/platform/chrome/cros_ec_sensorhub.c | 199 |
1 files changed, 199 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 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"); |