1ec2daf6eSJon Flatley // SPDX-License-Identifier: GPL-2.0-only 2ec2daf6eSJon Flatley /* 3ec2daf6eSJon Flatley * Copyright 2020 Google LLC 4ec2daf6eSJon Flatley * 5ec2daf6eSJon Flatley * This driver serves as the receiver of cros_ec PD host events. 6ec2daf6eSJon Flatley */ 7ec2daf6eSJon Flatley 8ec2daf6eSJon Flatley #include <linux/acpi.h> 9ec2daf6eSJon Flatley #include <linux/module.h> 10ec2daf6eSJon Flatley #include <linux/platform_data/cros_ec_proto.h> 11ec2daf6eSJon Flatley #include <linux/platform_data/cros_usbpd_notify.h> 12ec2daf6eSJon Flatley #include <linux/platform_device.h> 13ec2daf6eSJon Flatley 14ec2daf6eSJon Flatley #define DRV_NAME "cros-usbpd-notify" 157e91e1acSPrashant Malani #define DRV_NAME_PLAT_ACPI "cros-usbpd-notify-acpi" 16ec2daf6eSJon Flatley #define ACPI_DRV_NAME "GOOG0003" 17ec2daf6eSJon Flatley 18ec2daf6eSJon Flatley static BLOCKING_NOTIFIER_HEAD(cros_usbpd_notifier_list); 19ec2daf6eSJon Flatley 20f5d84a21SPrashant Malani struct cros_usbpd_notify_data { 21f5d84a21SPrashant Malani struct device *dev; 22f5d84a21SPrashant Malani struct cros_ec_device *ec; 23f5d84a21SPrashant Malani struct notifier_block nb; 24f5d84a21SPrashant Malani }; 25f5d84a21SPrashant Malani 26ec2daf6eSJon Flatley /** 27ec2daf6eSJon Flatley * cros_usbpd_register_notify - Register a notifier callback for PD events. 28ec2daf6eSJon Flatley * @nb: Notifier block pointer to register 29ec2daf6eSJon Flatley * 30ec2daf6eSJon Flatley * On ACPI platforms this corresponds to host events on the ECPD 31ec2daf6eSJon Flatley * "GOOG0003" ACPI device. On non-ACPI platforms this will filter mkbp events 32ec2daf6eSJon Flatley * for USB PD events. 33ec2daf6eSJon Flatley * 34ec2daf6eSJon Flatley * Return: 0 on success or negative error code. 35ec2daf6eSJon Flatley */ 36ec2daf6eSJon Flatley int cros_usbpd_register_notify(struct notifier_block *nb) 37ec2daf6eSJon Flatley { 38ec2daf6eSJon Flatley return blocking_notifier_chain_register(&cros_usbpd_notifier_list, 39ec2daf6eSJon Flatley nb); 40ec2daf6eSJon Flatley } 41ec2daf6eSJon Flatley EXPORT_SYMBOL_GPL(cros_usbpd_register_notify); 42ec2daf6eSJon Flatley 43ec2daf6eSJon Flatley /** 44ec2daf6eSJon Flatley * cros_usbpd_unregister_notify - Unregister notifier callback for PD events. 45ec2daf6eSJon Flatley * @nb: Notifier block pointer to unregister 46ec2daf6eSJon Flatley * 47ec2daf6eSJon Flatley * Unregister a notifier callback that was previously registered with 48ec2daf6eSJon Flatley * cros_usbpd_register_notify(). 49ec2daf6eSJon Flatley */ 50ec2daf6eSJon Flatley void cros_usbpd_unregister_notify(struct notifier_block *nb) 51ec2daf6eSJon Flatley { 52ec2daf6eSJon Flatley blocking_notifier_chain_unregister(&cros_usbpd_notifier_list, nb); 53ec2daf6eSJon Flatley } 54ec2daf6eSJon Flatley EXPORT_SYMBOL_GPL(cros_usbpd_unregister_notify); 55ec2daf6eSJon Flatley 56a8821408SPrashant Malani static void cros_usbpd_get_event_and_notify(struct device *dev, 57a8821408SPrashant Malani struct cros_ec_device *ec_dev) 58a8821408SPrashant Malani { 59a8821408SPrashant Malani struct ec_response_host_event_status host_event_status; 60a8821408SPrashant Malani u32 event = 0; 61a8821408SPrashant Malani int ret; 62a8821408SPrashant Malani 63a8821408SPrashant Malani /* 64a8821408SPrashant Malani * We still send a 0 event out to older devices which don't 65a8821408SPrashant Malani * have the updated device heirarchy. 66a8821408SPrashant Malani */ 67a8821408SPrashant Malani if (!ec_dev) { 68a8821408SPrashant Malani dev_dbg(dev, 69a8821408SPrashant Malani "EC device inaccessible; sending 0 event status.\n"); 70a8821408SPrashant Malani goto send_notify; 71a8821408SPrashant Malani } 72a8821408SPrashant Malani 73a8821408SPrashant Malani /* Check for PD host events on EC. */ 74*b1d288d9SPrashant Malani ret = cros_ec_cmd(ec_dev, 0, EC_CMD_PD_HOST_EVENT_STATUS, 755d122256SPrashant Malani NULL, 0, &host_event_status, sizeof(host_event_status)); 76a8821408SPrashant Malani if (ret < 0) { 77a8821408SPrashant Malani dev_warn(dev, "Can't get host event status (err: %d)\n", ret); 78a8821408SPrashant Malani goto send_notify; 79a8821408SPrashant Malani } 80a8821408SPrashant Malani 81a8821408SPrashant Malani event = host_event_status.status; 82a8821408SPrashant Malani 83a8821408SPrashant Malani send_notify: 84a8821408SPrashant Malani blocking_notifier_call_chain(&cros_usbpd_notifier_list, event, NULL); 85a8821408SPrashant Malani } 86a8821408SPrashant Malani 87ec2daf6eSJon Flatley #ifdef CONFIG_ACPI 88ec2daf6eSJon Flatley 897e91e1acSPrashant Malani static void cros_usbpd_notify_acpi(acpi_handle device, u32 event, void *data) 90ec2daf6eSJon Flatley { 91a8821408SPrashant Malani struct cros_usbpd_notify_data *pdnotify = data; 92a8821408SPrashant Malani 93a8821408SPrashant Malani cros_usbpd_get_event_and_notify(pdnotify->dev, pdnotify->ec); 947e91e1acSPrashant Malani } 957e91e1acSPrashant Malani 967e91e1acSPrashant Malani static int cros_usbpd_notify_probe_acpi(struct platform_device *pdev) 977e91e1acSPrashant Malani { 987e91e1acSPrashant Malani struct cros_usbpd_notify_data *pdnotify; 997e91e1acSPrashant Malani struct device *dev = &pdev->dev; 1007e91e1acSPrashant Malani struct acpi_device *adev; 1017e91e1acSPrashant Malani struct cros_ec_device *ec_dev; 1027e91e1acSPrashant Malani acpi_status status; 1037e91e1acSPrashant Malani 1047e91e1acSPrashant Malani adev = ACPI_COMPANION(dev); 1057e91e1acSPrashant Malani 1067e91e1acSPrashant Malani pdnotify = devm_kzalloc(dev, sizeof(*pdnotify), GFP_KERNEL); 1077e91e1acSPrashant Malani if (!pdnotify) 1087e91e1acSPrashant Malani return -ENOMEM; 1097e91e1acSPrashant Malani 1107e91e1acSPrashant Malani /* Get the EC device pointer needed to talk to the EC. */ 1117e91e1acSPrashant Malani ec_dev = dev_get_drvdata(dev->parent); 1127e91e1acSPrashant Malani if (!ec_dev) { 1137e91e1acSPrashant Malani /* 1147e91e1acSPrashant Malani * We continue even for older devices which don't have the 1157e91e1acSPrashant Malani * correct device heirarchy, namely, GOOG0003 is a child 1167e91e1acSPrashant Malani * of GOOG0004. 1177e91e1acSPrashant Malani */ 1187e91e1acSPrashant Malani dev_warn(dev, "Couldn't get Chrome EC device pointer.\n"); 1197e91e1acSPrashant Malani } 1207e91e1acSPrashant Malani 1217e91e1acSPrashant Malani pdnotify->dev = dev; 1227e91e1acSPrashant Malani pdnotify->ec = ec_dev; 1237e91e1acSPrashant Malani 1247e91e1acSPrashant Malani status = acpi_install_notify_handler(adev->handle, 1257e91e1acSPrashant Malani ACPI_ALL_NOTIFY, 1267e91e1acSPrashant Malani cros_usbpd_notify_acpi, 1277e91e1acSPrashant Malani pdnotify); 1287e91e1acSPrashant Malani if (ACPI_FAILURE(status)) { 1297e91e1acSPrashant Malani dev_warn(dev, "Failed to register notify handler %08x\n", 1307e91e1acSPrashant Malani status); 1317e91e1acSPrashant Malani return -EINVAL; 1327e91e1acSPrashant Malani } 1337e91e1acSPrashant Malani 134ec2daf6eSJon Flatley return 0; 135ec2daf6eSJon Flatley } 136ec2daf6eSJon Flatley 1377e91e1acSPrashant Malani static int cros_usbpd_notify_remove_acpi(struct platform_device *pdev) 138ec2daf6eSJon Flatley { 1397e91e1acSPrashant Malani struct device *dev = &pdev->dev; 1407e91e1acSPrashant Malani struct acpi_device *adev = ACPI_COMPANION(dev); 1417e91e1acSPrashant Malani 1427e91e1acSPrashant Malani acpi_remove_notify_handler(adev->handle, ACPI_ALL_NOTIFY, 1437e91e1acSPrashant Malani cros_usbpd_notify_acpi); 1447e91e1acSPrashant Malani 1457e91e1acSPrashant Malani return 0; 146ec2daf6eSJon Flatley } 147ec2daf6eSJon Flatley 148ec2daf6eSJon Flatley static const struct acpi_device_id cros_usbpd_notify_acpi_device_ids[] = { 149ec2daf6eSJon Flatley { ACPI_DRV_NAME, 0 }, 150ec2daf6eSJon Flatley { } 151ec2daf6eSJon Flatley }; 152ec2daf6eSJon Flatley MODULE_DEVICE_TABLE(acpi, cros_usbpd_notify_acpi_device_ids); 153ec2daf6eSJon Flatley 1547e91e1acSPrashant Malani static struct platform_driver cros_usbpd_notify_acpi_driver = { 1557e91e1acSPrashant Malani .driver = { 1567e91e1acSPrashant Malani .name = DRV_NAME_PLAT_ACPI, 1577e91e1acSPrashant Malani .acpi_match_table = cros_usbpd_notify_acpi_device_ids, 158ec2daf6eSJon Flatley }, 1597e91e1acSPrashant Malani .probe = cros_usbpd_notify_probe_acpi, 1607e91e1acSPrashant Malani .remove = cros_usbpd_notify_remove_acpi, 161ec2daf6eSJon Flatley }; 162ec2daf6eSJon Flatley 163ec2daf6eSJon Flatley #endif /* CONFIG_ACPI */ 164ec2daf6eSJon Flatley 165ec2daf6eSJon Flatley static int cros_usbpd_notify_plat(struct notifier_block *nb, 166ec2daf6eSJon Flatley unsigned long queued_during_suspend, 167ec2daf6eSJon Flatley void *data) 168ec2daf6eSJon Flatley { 169a8821408SPrashant Malani struct cros_usbpd_notify_data *pdnotify = container_of(nb, 170a8821408SPrashant Malani struct cros_usbpd_notify_data, nb); 171ec2daf6eSJon Flatley struct cros_ec_device *ec_dev = (struct cros_ec_device *)data; 172ec2daf6eSJon Flatley u32 host_event = cros_ec_get_host_event(ec_dev); 173ec2daf6eSJon Flatley 174ec2daf6eSJon Flatley if (!host_event) 17592e399c0SGwendal Grignou return NOTIFY_DONE; 176ec2daf6eSJon Flatley 1774423ee65SPi-Hsun Shih if (host_event & (EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) | 1784423ee65SPi-Hsun Shih EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX))) { 179a8821408SPrashant Malani cros_usbpd_get_event_and_notify(pdnotify->dev, ec_dev); 180ec2daf6eSJon Flatley return NOTIFY_OK; 181ec2daf6eSJon Flatley } 182ec2daf6eSJon Flatley return NOTIFY_DONE; 183ec2daf6eSJon Flatley } 184ec2daf6eSJon Flatley 185ec2daf6eSJon Flatley static int cros_usbpd_notify_probe_plat(struct platform_device *pdev) 186ec2daf6eSJon Flatley { 187ec2daf6eSJon Flatley struct device *dev = &pdev->dev; 188ec2daf6eSJon Flatley struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent); 189f5d84a21SPrashant Malani struct cros_usbpd_notify_data *pdnotify; 190ec2daf6eSJon Flatley int ret; 191ec2daf6eSJon Flatley 192f5d84a21SPrashant Malani pdnotify = devm_kzalloc(dev, sizeof(*pdnotify), GFP_KERNEL); 193f5d84a21SPrashant Malani if (!pdnotify) 194ec2daf6eSJon Flatley return -ENOMEM; 195ec2daf6eSJon Flatley 196f5d84a21SPrashant Malani pdnotify->dev = dev; 197f5d84a21SPrashant Malani pdnotify->ec = ecdev->ec_dev; 198f5d84a21SPrashant Malani pdnotify->nb.notifier_call = cros_usbpd_notify_plat; 199f5d84a21SPrashant Malani 200f5d84a21SPrashant Malani dev_set_drvdata(dev, pdnotify); 201ec2daf6eSJon Flatley 202ec2daf6eSJon Flatley ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier, 203f5d84a21SPrashant Malani &pdnotify->nb); 204ec2daf6eSJon Flatley if (ret < 0) { 205ec2daf6eSJon Flatley dev_err(dev, "Failed to register notifier\n"); 206ec2daf6eSJon Flatley return ret; 207ec2daf6eSJon Flatley } 208ec2daf6eSJon Flatley 209ec2daf6eSJon Flatley return 0; 210ec2daf6eSJon Flatley } 211ec2daf6eSJon Flatley 212ec2daf6eSJon Flatley static int cros_usbpd_notify_remove_plat(struct platform_device *pdev) 213ec2daf6eSJon Flatley { 214ec2daf6eSJon Flatley struct device *dev = &pdev->dev; 215ec2daf6eSJon Flatley struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent); 216f5d84a21SPrashant Malani struct cros_usbpd_notify_data *pdnotify = 217f5d84a21SPrashant Malani (struct cros_usbpd_notify_data *)dev_get_drvdata(dev); 218ec2daf6eSJon Flatley 219f5d84a21SPrashant Malani blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier, 220f5d84a21SPrashant Malani &pdnotify->nb); 221ec2daf6eSJon Flatley 222ec2daf6eSJon Flatley return 0; 223ec2daf6eSJon Flatley } 224ec2daf6eSJon Flatley 225ec2daf6eSJon Flatley static struct platform_driver cros_usbpd_notify_plat_driver = { 226ec2daf6eSJon Flatley .driver = { 227ec2daf6eSJon Flatley .name = DRV_NAME, 228ec2daf6eSJon Flatley }, 229ec2daf6eSJon Flatley .probe = cros_usbpd_notify_probe_plat, 230ec2daf6eSJon Flatley .remove = cros_usbpd_notify_remove_plat, 231ec2daf6eSJon Flatley }; 232ec2daf6eSJon Flatley 233ec2daf6eSJon Flatley static int __init cros_usbpd_notify_init(void) 234ec2daf6eSJon Flatley { 235ec2daf6eSJon Flatley int ret; 236ec2daf6eSJon Flatley 237ec2daf6eSJon Flatley ret = platform_driver_register(&cros_usbpd_notify_plat_driver); 238ec2daf6eSJon Flatley if (ret < 0) 239ec2daf6eSJon Flatley return ret; 240ec2daf6eSJon Flatley 241ec2daf6eSJon Flatley #ifdef CONFIG_ACPI 2427e91e1acSPrashant Malani platform_driver_register(&cros_usbpd_notify_acpi_driver); 243ec2daf6eSJon Flatley #endif 244ec2daf6eSJon Flatley return 0; 245ec2daf6eSJon Flatley } 246ec2daf6eSJon Flatley 247ec2daf6eSJon Flatley static void __exit cros_usbpd_notify_exit(void) 248ec2daf6eSJon Flatley { 249ec2daf6eSJon Flatley #ifdef CONFIG_ACPI 2507e91e1acSPrashant Malani platform_driver_unregister(&cros_usbpd_notify_acpi_driver); 251ec2daf6eSJon Flatley #endif 252ec2daf6eSJon Flatley platform_driver_unregister(&cros_usbpd_notify_plat_driver); 253ec2daf6eSJon Flatley } 254ec2daf6eSJon Flatley 255ec2daf6eSJon Flatley module_init(cros_usbpd_notify_init); 256ec2daf6eSJon Flatley module_exit(cros_usbpd_notify_exit); 257ec2daf6eSJon Flatley 258ec2daf6eSJon Flatley MODULE_LICENSE("GPL"); 259ec2daf6eSJon Flatley MODULE_DESCRIPTION("ChromeOS power delivery notifier device"); 260ec2daf6eSJon Flatley MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>"); 261ec2daf6eSJon Flatley MODULE_ALIAS("platform:" DRV_NAME); 262