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path: root/drivers/platform/chrome/cros_ec_sensorhub.c
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Diffstat (limited to 'drivers/platform/chrome/cros_ec_sensorhub.c')
-rw-r--r--drivers/platform/chrome/cros_ec_sensorhub.c199
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");