1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ChromeOS Embedded Controller 4 * 5 * Copyright (C) 2014 Google, Inc. 6 */ 7 8 #include <linux/dmi.h> 9 #include <linux/kconfig.h> 10 #include <linux/mfd/core.h> 11 #include <linux/module.h> 12 #include <linux/mod_devicetable.h> 13 #include <linux/of.h> 14 #include <linux/platform_device.h> 15 #include <linux/platform_data/cros_ec_chardev.h> 16 #include <linux/platform_data/cros_ec_commands.h> 17 #include <linux/platform_data/cros_ec_proto.h> 18 #include <linux/slab.h> 19 20 #define DRV_NAME "cros-ec-dev" 21 22 static struct class cros_class = { 23 .name = "chromeos", 24 }; 25 26 /** 27 * struct cros_feature_to_name - CrOS feature id to name/short description. 28 * @id: The feature identifier. 29 * @name: Device name associated with the feature id. 30 * @desc: Short name that will be displayed. 31 */ 32 struct cros_feature_to_name { 33 unsigned int id; 34 const char *name; 35 const char *desc; 36 }; 37 38 /** 39 * struct cros_feature_to_cells - CrOS feature id to mfd cells association. 40 * @id: The feature identifier. 41 * @mfd_cells: Pointer to the array of mfd cells that needs to be added. 42 * @num_cells: Number of mfd cells into the array. 43 */ 44 struct cros_feature_to_cells { 45 unsigned int id; 46 const struct mfd_cell *mfd_cells; 47 unsigned int num_cells; 48 }; 49 50 static const struct cros_feature_to_name cros_mcu_devices[] = { 51 { 52 .id = EC_FEATURE_FINGERPRINT, 53 .name = CROS_EC_DEV_FP_NAME, 54 .desc = "Fingerprint", 55 }, 56 { 57 .id = EC_FEATURE_ISH, 58 .name = CROS_EC_DEV_ISH_NAME, 59 .desc = "Integrated Sensor Hub", 60 }, 61 { 62 .id = EC_FEATURE_SCP, 63 .name = CROS_EC_DEV_SCP_NAME, 64 .desc = "System Control Processor", 65 }, 66 { 67 .id = EC_FEATURE_TOUCHPAD, 68 .name = CROS_EC_DEV_TP_NAME, 69 .desc = "Touchpad", 70 }, 71 }; 72 73 static const struct mfd_cell cros_ec_cec_cells[] = { 74 { .name = "cros-ec-cec", }, 75 }; 76 77 static const struct mfd_cell cros_ec_gpio_cells[] = { 78 { .name = "cros-ec-gpio", }, 79 }; 80 81 static const struct mfd_cell cros_ec_rtc_cells[] = { 82 { .name = "cros-ec-rtc", }, 83 }; 84 85 static const struct mfd_cell cros_ec_sensorhub_cells[] = { 86 { .name = "cros-ec-sensorhub", }, 87 }; 88 89 static const struct mfd_cell cros_usbpd_charger_cells[] = { 90 { .name = "cros-charge-control", }, 91 { .name = "cros-usbpd-charger", }, 92 { .name = "cros-usbpd-logger", }, 93 }; 94 95 static const struct mfd_cell cros_usbpd_notify_cells[] = { 96 { .name = "cros-usbpd-notify", }, 97 }; 98 99 static const struct mfd_cell cros_ec_wdt_cells[] = { 100 { .name = "cros-ec-wdt", } 101 }; 102 103 static const struct mfd_cell cros_ec_led_cells[] = { 104 { .name = "cros-ec-led", }, 105 }; 106 107 static const struct mfd_cell cros_ec_keyboard_leds_cells[] = { 108 { .name = "cros-keyboard-leds", }, 109 }; 110 111 static const struct mfd_cell cros_ec_ucsi_cells[] = { 112 { .name = "cros_ec_ucsi", }, 113 }; 114 115 static const struct cros_feature_to_cells cros_subdevices[] = { 116 { 117 .id = EC_FEATURE_CEC, 118 .mfd_cells = cros_ec_cec_cells, 119 .num_cells = ARRAY_SIZE(cros_ec_cec_cells), 120 }, 121 { 122 .id = EC_FEATURE_GPIO, 123 .mfd_cells = cros_ec_gpio_cells, 124 .num_cells = ARRAY_SIZE(cros_ec_gpio_cells), 125 }, 126 { 127 .id = EC_FEATURE_RTC, 128 .mfd_cells = cros_ec_rtc_cells, 129 .num_cells = ARRAY_SIZE(cros_ec_rtc_cells), 130 }, 131 { 132 .id = EC_FEATURE_UCSI_PPM, 133 .mfd_cells = cros_ec_ucsi_cells, 134 .num_cells = ARRAY_SIZE(cros_ec_ucsi_cells), 135 }, 136 { 137 .id = EC_FEATURE_HANG_DETECT, 138 .mfd_cells = cros_ec_wdt_cells, 139 .num_cells = ARRAY_SIZE(cros_ec_wdt_cells), 140 }, 141 { 142 .id = EC_FEATURE_LED, 143 .mfd_cells = cros_ec_led_cells, 144 .num_cells = ARRAY_SIZE(cros_ec_led_cells), 145 }, 146 { 147 .id = EC_FEATURE_PWM_KEYB, 148 .mfd_cells = cros_ec_keyboard_leds_cells, 149 .num_cells = ARRAY_SIZE(cros_ec_keyboard_leds_cells), 150 }, 151 }; 152 153 static const struct mfd_cell cros_ec_platform_cells[] = { 154 { .name = "cros-ec-chardev", }, 155 { .name = "cros-ec-debugfs", }, 156 { .name = "cros-ec-hwmon", }, 157 { .name = "cros-ec-sysfs", }, 158 }; 159 160 static const struct mfd_cell cros_ec_pchg_cells[] = { 161 { .name = "cros-ec-pchg", }, 162 }; 163 164 static const struct mfd_cell cros_ec_lightbar_cells[] = { 165 { .name = "cros-ec-lightbar", } 166 }; 167 168 static const struct mfd_cell cros_ec_vbc_cells[] = { 169 { .name = "cros-ec-vbc", } 170 }; 171 172 static void cros_ec_class_release(struct device *dev) 173 { 174 kfree(to_cros_ec_dev(dev)); 175 } 176 177 static int ec_device_probe(struct platform_device *pdev) 178 { 179 int retval = -ENOMEM; 180 struct device_node *node; 181 struct device *dev = &pdev->dev; 182 struct cros_ec_platform *ec_platform = dev_get_platdata(dev); 183 struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL); 184 struct ec_response_pchg_count pchg_count; 185 int i; 186 187 if (!ec) 188 return retval; 189 190 dev_set_drvdata(dev, ec); 191 ec->ec_dev = dev_get_drvdata(dev->parent); 192 ec->dev = dev; 193 ec->cmd_offset = ec_platform->cmd_offset; 194 ec->features.flags[0] = -1U; /* Not cached yet */ 195 ec->features.flags[1] = -1U; /* Not cached yet */ 196 device_initialize(&ec->class_dev); 197 198 for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) { 199 /* 200 * Check whether this is actually a dedicated MCU rather 201 * than an standard EC. 202 */ 203 if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) { 204 dev_info(dev, "CrOS %s MCU detected\n", 205 cros_mcu_devices[i].desc); 206 /* 207 * Help userspace differentiating ECs from other MCU, 208 * regardless of the probing order. 209 */ 210 ec_platform->ec_name = cros_mcu_devices[i].name; 211 break; 212 } 213 } 214 215 /* 216 * Add the class device 217 */ 218 ec->class_dev.class = &cros_class; 219 ec->class_dev.parent = dev; 220 ec->class_dev.release = cros_ec_class_release; 221 222 retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name); 223 if (retval) { 224 dev_err(dev, "dev_set_name failed => %d\n", retval); 225 goto failed; 226 } 227 228 retval = device_add(&ec->class_dev); 229 if (retval) 230 goto failed; 231 232 /* check whether this EC is a sensor hub. */ 233 if (cros_ec_get_sensor_count(ec) > 0) { 234 retval = mfd_add_hotplug_devices(ec->dev, 235 cros_ec_sensorhub_cells, 236 ARRAY_SIZE(cros_ec_sensorhub_cells)); 237 if (retval) 238 dev_err(ec->dev, "failed to add %s subdevice: %d\n", 239 cros_ec_sensorhub_cells->name, retval); 240 } 241 242 /* 243 * The following subdevices can be detected by sending the 244 * EC_FEATURE_GET_CMD Embedded Controller device. 245 */ 246 for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) { 247 if (cros_ec_check_features(ec, cros_subdevices[i].id)) { 248 retval = mfd_add_hotplug_devices(ec->dev, 249 cros_subdevices[i].mfd_cells, 250 cros_subdevices[i].num_cells); 251 if (retval) 252 dev_err(ec->dev, 253 "failed to add %s subdevice: %d\n", 254 cros_subdevices[i].mfd_cells->name, 255 retval); 256 } 257 } 258 259 /* 260 * UCSI provides power supply information so we don't need to separately 261 * load the cros_usbpd_charger driver. 262 */ 263 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD) && 264 !cros_ec_check_features(ec, EC_FEATURE_UCSI_PPM)) { 265 retval = mfd_add_hotplug_devices(ec->dev, 266 cros_usbpd_charger_cells, 267 ARRAY_SIZE(cros_usbpd_charger_cells)); 268 269 if (retval) 270 dev_warn(ec->dev, "failed to add usbpd-charger: %d\n", 271 retval); 272 } 273 274 /* 275 * Lightbar is a special case. Newer devices support autodetection, 276 * but older ones do not. 277 */ 278 if (cros_ec_check_features(ec, EC_FEATURE_LIGHTBAR) || 279 dmi_match(DMI_PRODUCT_NAME, "Link")) { 280 retval = mfd_add_hotplug_devices(ec->dev, 281 cros_ec_lightbar_cells, 282 ARRAY_SIZE(cros_ec_lightbar_cells)); 283 if (retval) 284 dev_warn(ec->dev, "failed to add lightbar: %d\n", 285 retval); 286 } 287 288 /* 289 * The PD notifier driver cell is separate since it only needs to be 290 * explicitly added on platforms that don't have the PD notifier ACPI 291 * device entry defined. 292 */ 293 if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) { 294 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) { 295 retval = mfd_add_hotplug_devices(ec->dev, 296 cros_usbpd_notify_cells, 297 ARRAY_SIZE(cros_usbpd_notify_cells)); 298 if (retval) 299 dev_err(ec->dev, 300 "failed to add PD notify devices: %d\n", 301 retval); 302 } 303 } 304 305 /* 306 * The PCHG device cannot be detected by sending EC_FEATURE_GET_CMD, but 307 * it can be detected by querying the number of peripheral chargers. 308 */ 309 retval = cros_ec_cmd(ec->ec_dev, 0, EC_CMD_PCHG_COUNT, NULL, 0, 310 &pchg_count, sizeof(pchg_count)); 311 if (retval >= 0 && pchg_count.port_count) { 312 retval = mfd_add_hotplug_devices(ec->dev, 313 cros_ec_pchg_cells, 314 ARRAY_SIZE(cros_ec_pchg_cells)); 315 if (retval) 316 dev_warn(ec->dev, "failed to add pchg: %d\n", 317 retval); 318 } 319 320 /* 321 * The following subdevices cannot be detected by sending the 322 * EC_FEATURE_GET_CMD to the Embedded Controller device. 323 */ 324 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_platform_cells, 325 ARRAY_SIZE(cros_ec_platform_cells)); 326 if (retval) 327 dev_warn(ec->dev, 328 "failed to add cros-ec platform devices: %d\n", 329 retval); 330 331 /* Check whether this EC instance has a VBC NVRAM */ 332 node = ec->ec_dev->dev->of_node; 333 if (of_property_read_bool(node, "google,has-vbc-nvram")) { 334 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_vbc_cells, 335 ARRAY_SIZE(cros_ec_vbc_cells)); 336 if (retval) 337 dev_warn(ec->dev, "failed to add VBC devices: %d\n", 338 retval); 339 } 340 341 return 0; 342 343 failed: 344 put_device(&ec->class_dev); 345 return retval; 346 } 347 348 static void ec_device_remove(struct platform_device *pdev) 349 { 350 struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev); 351 352 mfd_remove_devices(ec->dev); 353 device_unregister(&ec->class_dev); 354 } 355 356 static const struct platform_device_id cros_ec_id[] = { 357 { DRV_NAME, 0 }, 358 { /* sentinel */ } 359 }; 360 MODULE_DEVICE_TABLE(platform, cros_ec_id); 361 362 static struct platform_driver cros_ec_dev_driver = { 363 .driver = { 364 .name = DRV_NAME, 365 }, 366 .id_table = cros_ec_id, 367 .probe = ec_device_probe, 368 .remove = ec_device_remove, 369 }; 370 371 static int __init cros_ec_dev_init(void) 372 { 373 int ret; 374 375 ret = class_register(&cros_class); 376 if (ret) { 377 pr_err(CROS_EC_DEV_NAME ": failed to register device class\n"); 378 return ret; 379 } 380 381 ret = platform_driver_register(&cros_ec_dev_driver); 382 if (ret) { 383 pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret); 384 class_unregister(&cros_class); 385 } 386 return ret; 387 } 388 389 static void __exit cros_ec_dev_exit(void) 390 { 391 platform_driver_unregister(&cros_ec_dev_driver); 392 class_unregister(&cros_class); 393 } 394 395 module_init(cros_ec_dev_init); 396 module_exit(cros_ec_dev_exit); 397 398 MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>"); 399 MODULE_DESCRIPTION("ChromeOS Embedded Controller"); 400 MODULE_VERSION("1.0"); 401 MODULE_LICENSE("GPL"); 402