383 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ChromeOS Embedded Controller4 *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 22static 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 */32struct 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 */44struct cros_feature_to_cells {45 unsigned int id;46 const struct mfd_cell *mfd_cells;47 unsigned int num_cells;48};49 50static 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 73static const struct mfd_cell cros_ec_cec_cells[] = {74 { .name = "cros-ec-cec", },75};76 77static const struct mfd_cell cros_ec_gpio_cells[] = {78 { .name = "cros-ec-gpio", },79};80 81static const struct mfd_cell cros_ec_rtc_cells[] = {82 { .name = "cros-ec-rtc", },83};84 85static const struct mfd_cell cros_ec_sensorhub_cells[] = {86 { .name = "cros-ec-sensorhub", },87};88 89static 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 95static const struct mfd_cell cros_usbpd_notify_cells[] = {96 { .name = "cros-usbpd-notify", },97};98 99static const struct mfd_cell cros_ec_wdt_cells[] = {100 { .name = "cros-ec-wdt", }101};102 103static const struct mfd_cell cros_ec_led_cells[] = {104 { .name = "cros-ec-led", },105};106 107static const struct mfd_cell cros_ec_keyboard_leds_cells[] = {108 { .name = "cros-keyboard-leds", },109};110 111static const struct cros_feature_to_cells cros_subdevices[] = {112 {113 .id = EC_FEATURE_CEC,114 .mfd_cells = cros_ec_cec_cells,115 .num_cells = ARRAY_SIZE(cros_ec_cec_cells),116 },117 {118 .id = EC_FEATURE_GPIO,119 .mfd_cells = cros_ec_gpio_cells,120 .num_cells = ARRAY_SIZE(cros_ec_gpio_cells),121 },122 {123 .id = EC_FEATURE_RTC,124 .mfd_cells = cros_ec_rtc_cells,125 .num_cells = ARRAY_SIZE(cros_ec_rtc_cells),126 },127 {128 .id = EC_FEATURE_USB_PD,129 .mfd_cells = cros_usbpd_charger_cells,130 .num_cells = ARRAY_SIZE(cros_usbpd_charger_cells),131 },132 {133 .id = EC_FEATURE_HANG_DETECT,134 .mfd_cells = cros_ec_wdt_cells,135 .num_cells = ARRAY_SIZE(cros_ec_wdt_cells),136 },137 {138 .id = EC_FEATURE_LED,139 .mfd_cells = cros_ec_led_cells,140 .num_cells = ARRAY_SIZE(cros_ec_led_cells),141 },142 {143 .id = EC_FEATURE_PWM_KEYB,144 .mfd_cells = cros_ec_keyboard_leds_cells,145 .num_cells = ARRAY_SIZE(cros_ec_keyboard_leds_cells),146 },147};148 149static const struct mfd_cell cros_ec_platform_cells[] = {150 { .name = "cros-ec-chardev", },151 { .name = "cros-ec-debugfs", },152 { .name = "cros-ec-hwmon", },153 { .name = "cros-ec-sysfs", },154};155 156static const struct mfd_cell cros_ec_pchg_cells[] = {157 { .name = "cros-ec-pchg", },158};159 160static const struct mfd_cell cros_ec_lightbar_cells[] = {161 { .name = "cros-ec-lightbar", }162};163 164static const struct mfd_cell cros_ec_vbc_cells[] = {165 { .name = "cros-ec-vbc", }166};167 168static void cros_ec_class_release(struct device *dev)169{170 kfree(to_cros_ec_dev(dev));171}172 173static int ec_device_probe(struct platform_device *pdev)174{175 int retval = -ENOMEM;176 struct device_node *node;177 struct device *dev = &pdev->dev;178 struct cros_ec_platform *ec_platform = dev_get_platdata(dev);179 struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL);180 struct ec_response_pchg_count pchg_count;181 int i;182 183 if (!ec)184 return retval;185 186 dev_set_drvdata(dev, ec);187 ec->ec_dev = dev_get_drvdata(dev->parent);188 ec->dev = dev;189 ec->cmd_offset = ec_platform->cmd_offset;190 ec->features.flags[0] = -1U; /* Not cached yet */191 ec->features.flags[1] = -1U; /* Not cached yet */192 device_initialize(&ec->class_dev);193 194 for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {195 /*196 * Check whether this is actually a dedicated MCU rather197 * than an standard EC.198 */199 if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {200 dev_info(dev, "CrOS %s MCU detected\n",201 cros_mcu_devices[i].desc);202 /*203 * Help userspace differentiating ECs from other MCU,204 * regardless of the probing order.205 */206 ec_platform->ec_name = cros_mcu_devices[i].name;207 break;208 }209 }210 211 /*212 * Add the class device213 */214 ec->class_dev.class = &cros_class;215 ec->class_dev.parent = dev;216 ec->class_dev.release = cros_ec_class_release;217 218 retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name);219 if (retval) {220 dev_err(dev, "dev_set_name failed => %d\n", retval);221 goto failed;222 }223 224 retval = device_add(&ec->class_dev);225 if (retval)226 goto failed;227 228 /* check whether this EC is a sensor hub. */229 if (cros_ec_get_sensor_count(ec) > 0) {230 retval = mfd_add_hotplug_devices(ec->dev,231 cros_ec_sensorhub_cells,232 ARRAY_SIZE(cros_ec_sensorhub_cells));233 if (retval)234 dev_err(ec->dev, "failed to add %s subdevice: %d\n",235 cros_ec_sensorhub_cells->name, retval);236 }237 238 /*239 * The following subdevices can be detected by sending the240 * EC_FEATURE_GET_CMD Embedded Controller device.241 */242 for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) {243 if (cros_ec_check_features(ec, cros_subdevices[i].id)) {244 retval = mfd_add_hotplug_devices(ec->dev,245 cros_subdevices[i].mfd_cells,246 cros_subdevices[i].num_cells);247 if (retval)248 dev_err(ec->dev,249 "failed to add %s subdevice: %d\n",250 cros_subdevices[i].mfd_cells->name,251 retval);252 }253 }254 255 /*256 * Lightbar is a special case. Newer devices support autodetection,257 * but older ones do not.258 */259 if (cros_ec_check_features(ec, EC_FEATURE_LIGHTBAR) ||260 dmi_match(DMI_PRODUCT_NAME, "Link")) {261 retval = mfd_add_hotplug_devices(ec->dev,262 cros_ec_lightbar_cells,263 ARRAY_SIZE(cros_ec_lightbar_cells));264 if (retval)265 dev_warn(ec->dev, "failed to add lightbar: %d\n",266 retval);267 }268 269 /*270 * The PD notifier driver cell is separate since it only needs to be271 * explicitly added on platforms that don't have the PD notifier ACPI272 * device entry defined.273 */274 if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) {275 if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {276 retval = mfd_add_hotplug_devices(ec->dev,277 cros_usbpd_notify_cells,278 ARRAY_SIZE(cros_usbpd_notify_cells));279 if (retval)280 dev_err(ec->dev,281 "failed to add PD notify devices: %d\n",282 retval);283 }284 }285 286 /*287 * The PCHG device cannot be detected by sending EC_FEATURE_GET_CMD, but288 * it can be detected by querying the number of peripheral chargers.289 */290 retval = cros_ec_cmd(ec->ec_dev, 0, EC_CMD_PCHG_COUNT, NULL, 0,291 &pchg_count, sizeof(pchg_count));292 if (retval >= 0 && pchg_count.port_count) {293 retval = mfd_add_hotplug_devices(ec->dev,294 cros_ec_pchg_cells,295 ARRAY_SIZE(cros_ec_pchg_cells));296 if (retval)297 dev_warn(ec->dev, "failed to add pchg: %d\n",298 retval);299 }300 301 /*302 * The following subdevices cannot be detected by sending the303 * EC_FEATURE_GET_CMD to the Embedded Controller device.304 */305 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_platform_cells,306 ARRAY_SIZE(cros_ec_platform_cells));307 if (retval)308 dev_warn(ec->dev,309 "failed to add cros-ec platform devices: %d\n",310 retval);311 312 /* Check whether this EC instance has a VBC NVRAM */313 node = ec->ec_dev->dev->of_node;314 if (of_property_read_bool(node, "google,has-vbc-nvram")) {315 retval = mfd_add_hotplug_devices(ec->dev, cros_ec_vbc_cells,316 ARRAY_SIZE(cros_ec_vbc_cells));317 if (retval)318 dev_warn(ec->dev, "failed to add VBC devices: %d\n",319 retval);320 }321 322 return 0;323 324failed:325 put_device(&ec->class_dev);326 return retval;327}328 329static void ec_device_remove(struct platform_device *pdev)330{331 struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev);332 333 mfd_remove_devices(ec->dev);334 device_unregister(&ec->class_dev);335}336 337static const struct platform_device_id cros_ec_id[] = {338 { DRV_NAME, 0 },339 { /* sentinel */ }340};341MODULE_DEVICE_TABLE(platform, cros_ec_id);342 343static struct platform_driver cros_ec_dev_driver = {344 .driver = {345 .name = DRV_NAME,346 },347 .id_table = cros_ec_id,348 .probe = ec_device_probe,349 .remove_new = ec_device_remove,350};351 352static int __init cros_ec_dev_init(void)353{354 int ret;355 356 ret = class_register(&cros_class);357 if (ret) {358 pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");359 return ret;360 }361 362 ret = platform_driver_register(&cros_ec_dev_driver);363 if (ret) {364 pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);365 class_unregister(&cros_class);366 }367 return ret;368}369 370static void __exit cros_ec_dev_exit(void)371{372 platform_driver_unregister(&cros_ec_dev_driver);373 class_unregister(&cros_class);374}375 376module_init(cros_ec_dev_init);377module_exit(cros_ec_dev_exit);378 379MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");380MODULE_DESCRIPTION("ChromeOS Embedded Controller");381MODULE_VERSION("1.0");382MODULE_LICENSE("GPL");383