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1// SPDX-License-Identifier: GPL-2.02/*3 * Sensor HUB driver that discovers sensors behind a ChromeOS Embedded4 * Controller.5 *6 * Copyright 2019 Google LLC7 */8 9#include <linux/init.h>10#include <linux/device.h>11#include <linux/mod_devicetable.h>12#include <linux/module.h>13#include <linux/platform_data/cros_ec_commands.h>14#include <linux/platform_data/cros_ec_proto.h>15#include <linux/platform_data/cros_ec_sensorhub.h>16#include <linux/platform_device.h>17#include <linux/slab.h>18#include <linux/types.h>19 20#define DRV_NAME "cros-ec-sensorhub"21 22static void cros_ec_sensorhub_free_sensor(void *arg)23{24 struct platform_device *pdev = arg;25 26 platform_device_unregister(pdev);27}28 29static int cros_ec_sensorhub_allocate_sensor(struct device *parent,30 char *sensor_name,31 int sensor_num)32{33 struct cros_ec_sensor_platform sensor_platforms = {34 .sensor_num = sensor_num,35 };36 struct platform_device *pdev;37 38 pdev = platform_device_register_data(parent, sensor_name,39 PLATFORM_DEVID_AUTO,40 &sensor_platforms,41 sizeof(sensor_platforms));42 if (IS_ERR(pdev))43 return PTR_ERR(pdev);44 45 return devm_add_action_or_reset(parent,46 cros_ec_sensorhub_free_sensor,47 pdev);48}49 50static int cros_ec_sensorhub_register(struct device *dev,51 struct cros_ec_sensorhub *sensorhub)52{53 int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 };54 struct cros_ec_command *msg = sensorhub->msg;55 struct cros_ec_dev *ec = sensorhub->ec;56 int ret, i;57 char *name;58 59 60 msg->version = 1;61 msg->insize = sizeof(struct ec_response_motion_sense);62 msg->outsize = sizeof(struct ec_params_motion_sense);63 64 for (i = 0; i < sensorhub->sensor_num; i++) {65 sensorhub->params->cmd = MOTIONSENSE_CMD_INFO;66 sensorhub->params->info.sensor_num = i;67 68 ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);69 if (ret < 0) {70 dev_warn(dev, "no info for EC sensor %d : %d/%d\n",71 i, ret, msg->result);72 continue;73 }74 75 switch (sensorhub->resp->info.type) {76 case MOTIONSENSE_TYPE_ACCEL:77 name = "cros-ec-accel";78 break;79 case MOTIONSENSE_TYPE_BARO:80 name = "cros-ec-baro";81 break;82 case MOTIONSENSE_TYPE_GYRO:83 name = "cros-ec-gyro";84 break;85 case MOTIONSENSE_TYPE_MAG:86 name = "cros-ec-mag";87 break;88 case MOTIONSENSE_TYPE_PROX:89 name = "cros-ec-prox";90 break;91 case MOTIONSENSE_TYPE_LIGHT:92 name = "cros-ec-light";93 break;94 case MOTIONSENSE_TYPE_ACTIVITY:95 name = "cros-ec-activity";96 break;97 default:98 dev_warn(dev, "unknown type %d\n",99 sensorhub->resp->info.type);100 continue;101 }102 103 ret = cros_ec_sensorhub_allocate_sensor(dev, name, i);104 if (ret)105 return ret;106 107 sensor_type[sensorhub->resp->info.type]++;108 }109 110 if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2)111 ec->has_kb_wake_angle = true;112 113 if (cros_ec_check_features(ec,114 EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {115 ret = cros_ec_sensorhub_allocate_sensor(dev,116 "cros-ec-lid-angle",117 0);118 if (ret)119 return ret;120 }121 122 return 0;123}124 125static int cros_ec_sensorhub_probe(struct platform_device *pdev)126{127 struct device *dev = &pdev->dev;128 struct cros_ec_dev *ec = dev_get_drvdata(dev->parent);129 struct cros_ec_sensorhub *data;130 struct cros_ec_command *msg;131 int ret, i, sensor_num;132 133 msg = devm_kzalloc(dev, sizeof(struct cros_ec_command) +134 max((u16)sizeof(struct ec_params_motion_sense),135 ec->ec_dev->max_response), GFP_KERNEL);136 if (!msg)137 return -ENOMEM;138 139 msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;140 141 data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL);142 if (!data)143 return -ENOMEM;144 145 mutex_init(&data->cmd_lock);146 147 data->dev = dev;148 data->ec = ec;149 data->msg = msg;150 data->params = (struct ec_params_motion_sense *)msg->data;151 data->resp = (struct ec_response_motion_sense *)msg->data;152 153 dev_set_drvdata(dev, data);154 155 /* Check whether this EC is a sensor hub. */156 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) {157 sensor_num = cros_ec_get_sensor_count(ec);158 if (sensor_num < 0) {159 dev_err(dev,160 "Unable to retrieve sensor information (err:%d)\n",161 sensor_num);162 return sensor_num;163 }164 if (sensor_num == 0) {165 dev_err(dev, "Zero sensors reported.\n");166 return -EINVAL;167 }168 data->sensor_num = sensor_num;169 170 /*171 * Prepare the ring handler before enumering the172 * sensors.173 */174 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {175 ret = cros_ec_sensorhub_ring_allocate(data);176 if (ret)177 return ret;178 }179 180 /* Enumerate the sensors.*/181 ret = cros_ec_sensorhub_register(dev, data);182 if (ret)183 return ret;184 185 /*186 * When the EC does not have a FIFO, the sensors will query187 * their data themselves via sysfs or a software trigger.188 */189 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) {190 ret = cros_ec_sensorhub_ring_add(data);191 if (ret)192 return ret;193 /*194 * The msg and its data is not under the control of the195 * ring handler.196 */197 return devm_add_action_or_reset(dev,198 cros_ec_sensorhub_ring_remove,199 data);200 }201 202 } else {203 /*204 * If the device has sensors but does not claim to205 * be a sensor hub, we are in legacy mode.206 */207 data->sensor_num = 2;208 for (i = 0; i < data->sensor_num; i++) {209 ret = cros_ec_sensorhub_allocate_sensor(dev,210 "cros-ec-accel-legacy", i);211 if (ret)212 return ret;213 }214 }215 216 217 return 0;218}219 220#ifdef CONFIG_PM_SLEEP221/*222 * When the EC is suspending, we must stop sending interrupt,223 * we may use the same interrupt line for waking up the device.224 * Tell the EC to stop sending non-interrupt event on the iio ring.225 */226static int cros_ec_sensorhub_suspend(struct device *dev)227{228 struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev);229 struct cros_ec_dev *ec = sensorhub->ec;230 231 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))232 return cros_ec_sensorhub_ring_fifo_enable(sensorhub, false);233 return 0;234}235 236static int cros_ec_sensorhub_resume(struct device *dev)237{238 struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev);239 struct cros_ec_dev *ec = sensorhub->ec;240 241 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO))242 return cros_ec_sensorhub_ring_fifo_enable(sensorhub, true);243 return 0;244}245#endif246 247static SIMPLE_DEV_PM_OPS(cros_ec_sensorhub_pm_ops,248 cros_ec_sensorhub_suspend,249 cros_ec_sensorhub_resume);250 251static const struct platform_device_id cros_ec_sensorhub_id[] = {252 { DRV_NAME, 0 },253 {}254};255MODULE_DEVICE_TABLE(platform, cros_ec_sensorhub_id);256 257static struct platform_driver cros_ec_sensorhub_driver = {258 .driver = {259 .name = DRV_NAME,260 .pm = &cros_ec_sensorhub_pm_ops,261 },262 .probe = cros_ec_sensorhub_probe,263 .id_table = cros_ec_sensorhub_id,264};265 266module_platform_driver(cros_ec_sensorhub_driver);267 268MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");269MODULE_DESCRIPTION("ChromeOS EC MEMS Sensor Hub Driver");270MODULE_LICENSE("GPL");271