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 */
cros_usbpd_register_notify(struct notifier_block * nb)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 */
cros_usbpd_unregister_notify(struct notifier_block * nb)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
cros_usbpd_get_event_and_notify(struct device * dev,struct cros_ec_device * ec_dev)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. */
74b1d288d9SPrashant 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
cros_usbpd_notify_acpi(acpi_handle device,u32 event,void * data)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
cros_usbpd_notify_probe_acpi(struct platform_device * pdev)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
cros_usbpd_notify_remove_acpi(struct platform_device * pdev)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
cros_usbpd_notify_plat(struct notifier_block * nb,unsigned long queued_during_suspend,void * data)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
cros_usbpd_notify_probe_plat(struct platform_device * pdev)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
cros_usbpd_notify_remove_plat(struct platform_device * pdev)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
cros_usbpd_notify_init(void)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
242*5a2d9662SYuan Can ret = platform_driver_register(&cros_usbpd_notify_acpi_driver);
243*5a2d9662SYuan Can if (ret) {
244*5a2d9662SYuan Can platform_driver_unregister(&cros_usbpd_notify_plat_driver);
245*5a2d9662SYuan Can return ret;
246*5a2d9662SYuan Can }
247ec2daf6eSJon Flatley #endif
248ec2daf6eSJon Flatley return 0;
249ec2daf6eSJon Flatley }
250ec2daf6eSJon Flatley
cros_usbpd_notify_exit(void)251ec2daf6eSJon Flatley static void __exit cros_usbpd_notify_exit(void)
252ec2daf6eSJon Flatley {
253ec2daf6eSJon Flatley #ifdef CONFIG_ACPI
2547e91e1acSPrashant Malani platform_driver_unregister(&cros_usbpd_notify_acpi_driver);
255ec2daf6eSJon Flatley #endif
256ec2daf6eSJon Flatley platform_driver_unregister(&cros_usbpd_notify_plat_driver);
257ec2daf6eSJon Flatley }
258ec2daf6eSJon Flatley
259ec2daf6eSJon Flatley module_init(cros_usbpd_notify_init);
260ec2daf6eSJon Flatley module_exit(cros_usbpd_notify_exit);
261ec2daf6eSJon Flatley
262ec2daf6eSJon Flatley MODULE_LICENSE("GPL");
263ec2daf6eSJon Flatley MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
264ec2daf6eSJon Flatley MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
265ec2daf6eSJon Flatley MODULE_ALIAS("platform:" DRV_NAME);
266