1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Sensor HUB driver that discovers sensors behind a ChromeOS Embedded 4 * Controller. 5 * 6 * Copyright 2019 Google LLC 7 */ 8 9 #include <linux/init.h> 10 #include <linux/device.h> 11 #include <linux/module.h> 12 #include <linux/platform_data/cros_ec_commands.h> 13 #include <linux/platform_data/cros_ec_proto.h> 14 #include <linux/platform_data/cros_ec_sensorhub.h> 15 #include <linux/platform_device.h> 16 #include <linux/slab.h> 17 #include <linux/types.h> 18 19 #define DRV_NAME "cros-ec-sensorhub" 20 21 static void cros_ec_sensorhub_free_sensor(void *arg) 22 { 23 struct platform_device *pdev = arg; 24 25 platform_device_unregister(pdev); 26 } 27 28 static int cros_ec_sensorhub_allocate_sensor(struct device *parent, 29 char *sensor_name, 30 int sensor_num) 31 { 32 struct cros_ec_sensor_platform sensor_platforms = { 33 .sensor_num = sensor_num, 34 }; 35 struct platform_device *pdev; 36 37 pdev = platform_device_register_data(parent, sensor_name, 38 PLATFORM_DEVID_AUTO, 39 &sensor_platforms, 40 sizeof(sensor_platforms)); 41 if (IS_ERR(pdev)) 42 return PTR_ERR(pdev); 43 44 return devm_add_action_or_reset(parent, 45 cros_ec_sensorhub_free_sensor, 46 pdev); 47 } 48 49 static int cros_ec_sensorhub_register(struct device *dev, 50 struct cros_ec_sensorhub *sensorhub) 51 { 52 int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 }; 53 struct cros_ec_command *msg = sensorhub->msg; 54 struct cros_ec_dev *ec = sensorhub->ec; 55 int ret, i; 56 char *name; 57 58 59 msg->version = 1; 60 msg->insize = sizeof(struct ec_response_motion_sense); 61 msg->outsize = sizeof(struct ec_params_motion_sense); 62 63 for (i = 0; i < sensorhub->sensor_num; i++) { 64 sensorhub->params->cmd = MOTIONSENSE_CMD_INFO; 65 sensorhub->params->info.sensor_num = i; 66 67 ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg); 68 if (ret < 0) { 69 dev_warn(dev, "no info for EC sensor %d : %d/%d\n", 70 i, ret, msg->result); 71 continue; 72 } 73 74 switch (sensorhub->resp->info.type) { 75 case MOTIONSENSE_TYPE_ACCEL: 76 name = "cros-ec-accel"; 77 break; 78 case MOTIONSENSE_TYPE_BARO: 79 name = "cros-ec-baro"; 80 break; 81 case MOTIONSENSE_TYPE_GYRO: 82 name = "cros-ec-gyro"; 83 break; 84 case MOTIONSENSE_TYPE_MAG: 85 name = "cros-ec-mag"; 86 break; 87 case MOTIONSENSE_TYPE_PROX: 88 name = "cros-ec-prox"; 89 break; 90 case MOTIONSENSE_TYPE_LIGHT: 91 name = "cros-ec-light"; 92 break; 93 case MOTIONSENSE_TYPE_ACTIVITY: 94 name = "cros-ec-activity"; 95 break; 96 default: 97 dev_warn(dev, "unknown type %d\n", 98 sensorhub->resp->info.type); 99 continue; 100 } 101 102 ret = cros_ec_sensorhub_allocate_sensor(dev, name, i); 103 if (ret) 104 return ret; 105 106 sensor_type[sensorhub->resp->info.type]++; 107 } 108 109 if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2) 110 ec->has_kb_wake_angle = true; 111 112 if (cros_ec_check_features(ec, 113 EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) { 114 ret = cros_ec_sensorhub_allocate_sensor(dev, 115 "cros-ec-lid-angle", 116 0); 117 if (ret) 118 return ret; 119 } 120 121 return 0; 122 } 123 124 static int cros_ec_sensorhub_probe(struct platform_device *pdev) 125 { 126 struct device *dev = &pdev->dev; 127 struct cros_ec_dev *ec = dev_get_drvdata(dev->parent); 128 struct cros_ec_sensorhub *data; 129 struct cros_ec_command *msg; 130 int ret, i, sensor_num; 131 132 msg = devm_kzalloc(dev, sizeof(struct cros_ec_command) + 133 max((u16)sizeof(struct ec_params_motion_sense), 134 ec->ec_dev->max_response), GFP_KERNEL); 135 if (!msg) 136 return -ENOMEM; 137 138 msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset; 139 140 data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL); 141 if (!data) 142 return -ENOMEM; 143 144 mutex_init(&data->cmd_lock); 145 146 data->dev = dev; 147 data->ec = ec; 148 data->msg = msg; 149 data->params = (struct ec_params_motion_sense *)msg->data; 150 data->resp = (struct ec_response_motion_sense *)msg->data; 151 152 dev_set_drvdata(dev, data); 153 154 /* Check whether this EC is a sensor hub. */ 155 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE)) { 156 sensor_num = cros_ec_get_sensor_count(ec); 157 if (sensor_num < 0) { 158 dev_err(dev, 159 "Unable to retrieve sensor information (err:%d)\n", 160 sensor_num); 161 return sensor_num; 162 } 163 if (sensor_num == 0) { 164 dev_err(dev, "Zero sensors reported.\n"); 165 return -EINVAL; 166 } 167 data->sensor_num = sensor_num; 168 169 /* 170 * Prepare the ring handler before enumering the 171 * sensors. 172 */ 173 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) { 174 ret = cros_ec_sensorhub_ring_allocate(data); 175 if (ret) 176 return ret; 177 } 178 179 /* Enumerate the sensors.*/ 180 ret = cros_ec_sensorhub_register(dev, data); 181 if (ret) 182 return ret; 183 184 /* 185 * When the EC does not have a FIFO, the sensors will query 186 * their data themselves via sysfs or a software trigger. 187 */ 188 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) { 189 ret = cros_ec_sensorhub_ring_add(data); 190 if (ret) 191 return ret; 192 /* 193 * The msg and its data is not under the control of the 194 * ring handler. 195 */ 196 return devm_add_action_or_reset(dev, 197 cros_ec_sensorhub_ring_remove, 198 data); 199 } 200 201 } else { 202 /* 203 * If the device has sensors but does not claim to 204 * be a sensor hub, we are in legacy mode. 205 */ 206 data->sensor_num = 2; 207 for (i = 0; i < data->sensor_num; i++) { 208 ret = cros_ec_sensorhub_allocate_sensor(dev, 209 "cros-ec-accel-legacy", i); 210 if (ret) 211 return ret; 212 } 213 } 214 215 216 return 0; 217 } 218 219 #ifdef CONFIG_PM_SLEEP 220 /* 221 * When the EC is suspending, we must stop sending interrupt, 222 * we may use the same interrupt line for waking up the device. 223 * Tell the EC to stop sending non-interrupt event on the iio ring. 224 */ 225 static int cros_ec_sensorhub_suspend(struct device *dev) 226 { 227 struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev); 228 struct cros_ec_dev *ec = sensorhub->ec; 229 230 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) 231 return cros_ec_sensorhub_ring_fifo_enable(sensorhub, false); 232 return 0; 233 } 234 235 static int cros_ec_sensorhub_resume(struct device *dev) 236 { 237 struct cros_ec_sensorhub *sensorhub = dev_get_drvdata(dev); 238 struct cros_ec_dev *ec = sensorhub->ec; 239 240 if (cros_ec_check_features(ec, EC_FEATURE_MOTION_SENSE_FIFO)) 241 return cros_ec_sensorhub_ring_fifo_enable(sensorhub, true); 242 return 0; 243 } 244 #endif 245 246 static SIMPLE_DEV_PM_OPS(cros_ec_sensorhub_pm_ops, 247 cros_ec_sensorhub_suspend, 248 cros_ec_sensorhub_resume); 249 250 static struct platform_driver cros_ec_sensorhub_driver = { 251 .driver = { 252 .name = DRV_NAME, 253 .pm = &cros_ec_sensorhub_pm_ops, 254 }, 255 .probe = cros_ec_sensorhub_probe, 256 }; 257 258 module_platform_driver(cros_ec_sensorhub_driver); 259 260 MODULE_ALIAS("platform:" DRV_NAME); 261 MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>"); 262 MODULE_DESCRIPTION("ChromeOS EC MEMS Sensor Hub Driver"); 263 MODULE_LICENSE("GPL"); 264