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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2020 Google LLC
4 *
5 * This driver serves as the receiver of cros_ec PD host events.
6 */
7
8#include <linux/acpi.h>
9#include <linux/module.h>
10#include <linux/platform_data/cros_ec_proto.h>
11#include <linux/platform_data/cros_usbpd_notify.h>
12#include <linux/platform_device.h>
13
14#define DRV_NAME "cros-usbpd-notify"
15#define DRV_NAME_PLAT_ACPI "cros-usbpd-notify-acpi"
16#define ACPI_DRV_NAME "GOOG0003"
17
18static BLOCKING_NOTIFIER_HEAD(cros_usbpd_notifier_list);
19
20struct cros_usbpd_notify_data {
21 struct device *dev;
22 struct cros_ec_device *ec;
23 struct notifier_block nb;
24};
25
26/**
27 * cros_usbpd_register_notify - Register a notifier callback for PD events.
28 * @nb: Notifier block pointer to register
29 *
30 * On ACPI platforms this corresponds to host events on the ECPD
31 * "GOOG0003" ACPI device. On non-ACPI platforms this will filter mkbp events
32 * for USB PD events.
33 *
34 * Return: 0 on success or negative error code.
35 */
36int cros_usbpd_register_notify(struct notifier_block *nb)
37{
38 return blocking_notifier_chain_register(&cros_usbpd_notifier_list,
39 nb);
40}
41EXPORT_SYMBOL_GPL(cros_usbpd_register_notify);
42
43/**
44 * cros_usbpd_unregister_notify - Unregister notifier callback for PD events.
45 * @nb: Notifier block pointer to unregister
46 *
47 * Unregister a notifier callback that was previously registered with
48 * cros_usbpd_register_notify().
49 */
50void cros_usbpd_unregister_notify(struct notifier_block *nb)
51{
52 blocking_notifier_chain_unregister(&cros_usbpd_notifier_list, nb);
53}
54EXPORT_SYMBOL_GPL(cros_usbpd_unregister_notify);
55
56static void cros_usbpd_get_event_and_notify(struct device *dev,
57 struct cros_ec_device *ec_dev)
58{
59 struct ec_response_host_event_status host_event_status;
60 u32 event = 0;
61 int ret;
62
63 /*
64 * We still send a 0 event out to older devices which don't
65 * have the updated device heirarchy.
66 */
67 if (!ec_dev) {
68 dev_dbg(dev,
69 "EC device inaccessible; sending 0 event status.\n");
70 goto send_notify;
71 }
72
73 /* Check for PD host events on EC. */
74 ret = cros_ec_cmd(ec_dev, 0, EC_CMD_PD_HOST_EVENT_STATUS,
75 NULL, 0, &host_event_status, sizeof(host_event_status));
76 if (ret < 0) {
77 dev_warn(dev, "Can't get host event status (err: %d)\n", ret);
78 goto send_notify;
79 }
80
81 event = host_event_status.status;
82
83send_notify:
84 blocking_notifier_call_chain(&cros_usbpd_notifier_list, event, NULL);
85}
86
87#ifdef CONFIG_ACPI
88
89static void cros_usbpd_notify_acpi(acpi_handle device, u32 event, void *data)
90{
91 struct cros_usbpd_notify_data *pdnotify = data;
92
93 cros_usbpd_get_event_and_notify(pdnotify->dev, pdnotify->ec);
94}
95
96static int cros_usbpd_notify_probe_acpi(struct platform_device *pdev)
97{
98 struct cros_usbpd_notify_data *pdnotify;
99 struct device *dev = &pdev->dev;
100 struct acpi_device *adev;
101 struct cros_ec_device *ec_dev;
102 acpi_status status;
103
104 adev = ACPI_COMPANION(dev);
105
106 pdnotify = devm_kzalloc(dev, sizeof(*pdnotify), GFP_KERNEL);
107 if (!pdnotify)
108 return -ENOMEM;
109
110 /* Get the EC device pointer needed to talk to the EC. */
111 ec_dev = dev_get_drvdata(dev->parent);
112 if (!ec_dev) {
113 /*
114 * We continue even for older devices which don't have the
115 * correct device heirarchy, namely, GOOG0003 is a child
116 * of GOOG0004.
117 */
118 dev_warn(dev, "Couldn't get Chrome EC device pointer.\n");
119 }
120
121 pdnotify->dev = dev;
122 pdnotify->ec = ec_dev;
123
124 status = acpi_install_notify_handler(adev->handle,
125 ACPI_ALL_NOTIFY,
126 cros_usbpd_notify_acpi,
127 pdnotify);
128 if (ACPI_FAILURE(status)) {
129 dev_warn(dev, "Failed to register notify handler %08x\n",
130 status);
131 return -EINVAL;
132 }
133
134 return 0;
135}
136
137static void cros_usbpd_notify_remove_acpi(struct platform_device *pdev)
138{
139 struct device *dev = &pdev->dev;
140 struct acpi_device *adev = ACPI_COMPANION(dev);
141
142 acpi_remove_notify_handler(adev->handle, ACPI_ALL_NOTIFY,
143 cros_usbpd_notify_acpi);
144}
145
146static const struct acpi_device_id cros_usbpd_notify_acpi_device_ids[] = {
147 { ACPI_DRV_NAME, 0 },
148 { }
149};
150MODULE_DEVICE_TABLE(acpi, cros_usbpd_notify_acpi_device_ids);
151
152static struct platform_driver cros_usbpd_notify_acpi_driver = {
153 .driver = {
154 .name = DRV_NAME_PLAT_ACPI,
155 .acpi_match_table = cros_usbpd_notify_acpi_device_ids,
156 },
157 .probe = cros_usbpd_notify_probe_acpi,
158 .remove_new = cros_usbpd_notify_remove_acpi,
159};
160
161#endif /* CONFIG_ACPI */
162
163static int cros_usbpd_notify_plat(struct notifier_block *nb,
164 unsigned long queued_during_suspend,
165 void *data)
166{
167 struct cros_usbpd_notify_data *pdnotify = container_of(nb,
168 struct cros_usbpd_notify_data, nb);
169 struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
170 u32 host_event = cros_ec_get_host_event(ec_dev);
171
172 if (!host_event)
173 return NOTIFY_DONE;
174
175 if (host_event & (EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) |
176 EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX))) {
177 cros_usbpd_get_event_and_notify(pdnotify->dev, ec_dev);
178 return NOTIFY_OK;
179 }
180 return NOTIFY_DONE;
181}
182
183static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
184{
185 struct device *dev = &pdev->dev;
186 struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
187 struct cros_usbpd_notify_data *pdnotify;
188 int ret;
189
190 pdnotify = devm_kzalloc(dev, sizeof(*pdnotify), GFP_KERNEL);
191 if (!pdnotify)
192 return -ENOMEM;
193
194 pdnotify->dev = dev;
195 pdnotify->ec = ecdev->ec_dev;
196 pdnotify->nb.notifier_call = cros_usbpd_notify_plat;
197
198 dev_set_drvdata(dev, pdnotify);
199
200 ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
201 &pdnotify->nb);
202 if (ret < 0) {
203 dev_err(dev, "Failed to register notifier\n");
204 return ret;
205 }
206
207 return 0;
208}
209
210static void cros_usbpd_notify_remove_plat(struct platform_device *pdev)
211{
212 struct device *dev = &pdev->dev;
213 struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
214 struct cros_usbpd_notify_data *pdnotify =
215 (struct cros_usbpd_notify_data *)dev_get_drvdata(dev);
216
217 blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
218 &pdnotify->nb);
219}
220
221static struct platform_driver cros_usbpd_notify_plat_driver = {
222 .driver = {
223 .name = DRV_NAME,
224 },
225 .probe = cros_usbpd_notify_probe_plat,
226 .remove_new = cros_usbpd_notify_remove_plat,
227};
228
229static int __init cros_usbpd_notify_init(void)
230{
231 int ret;
232
233 ret = platform_driver_register(&cros_usbpd_notify_plat_driver);
234 if (ret < 0)
235 return ret;
236
237#ifdef CONFIG_ACPI
238 ret = platform_driver_register(&cros_usbpd_notify_acpi_driver);
239 if (ret) {
240 platform_driver_unregister(&cros_usbpd_notify_plat_driver);
241 return ret;
242 }
243#endif
244 return 0;
245}
246
247static void __exit cros_usbpd_notify_exit(void)
248{
249#ifdef CONFIG_ACPI
250 platform_driver_unregister(&cros_usbpd_notify_acpi_driver);
251#endif
252 platform_driver_unregister(&cros_usbpd_notify_plat_driver);
253}
254
255module_init(cros_usbpd_notify_init);
256module_exit(cros_usbpd_notify_exit);
257
258MODULE_LICENSE("GPL");
259MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
260MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
261MODULE_ALIAS("platform:" DRV_NAME);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2020 Google LLC
4 *
5 * This driver serves as the receiver of cros_ec PD host events.
6 */
7
8#include <linux/acpi.h>
9#include <linux/module.h>
10#include <linux/platform_data/cros_ec_proto.h>
11#include <linux/platform_data/cros_usbpd_notify.h>
12#include <linux/platform_device.h>
13
14#define DRV_NAME "cros-usbpd-notify"
15#define DRV_NAME_PLAT_ACPI "cros-usbpd-notify-acpi"
16#define ACPI_DRV_NAME "GOOG0003"
17
18static BLOCKING_NOTIFIER_HEAD(cros_usbpd_notifier_list);
19
20struct cros_usbpd_notify_data {
21 struct device *dev;
22 struct cros_ec_device *ec;
23 struct notifier_block nb;
24};
25
26/**
27 * cros_usbpd_register_notify - Register a notifier callback for PD events.
28 * @nb: Notifier block pointer to register
29 *
30 * On ACPI platforms this corresponds to host events on the ECPD
31 * "GOOG0003" ACPI device. On non-ACPI platforms this will filter mkbp events
32 * for USB PD events.
33 *
34 * Return: 0 on success or negative error code.
35 */
36int cros_usbpd_register_notify(struct notifier_block *nb)
37{
38 return blocking_notifier_chain_register(&cros_usbpd_notifier_list,
39 nb);
40}
41EXPORT_SYMBOL_GPL(cros_usbpd_register_notify);
42
43/**
44 * cros_usbpd_unregister_notify - Unregister notifier callback for PD events.
45 * @nb: Notifier block pointer to unregister
46 *
47 * Unregister a notifier callback that was previously registered with
48 * cros_usbpd_register_notify().
49 */
50void cros_usbpd_unregister_notify(struct notifier_block *nb)
51{
52 blocking_notifier_chain_unregister(&cros_usbpd_notifier_list, nb);
53}
54EXPORT_SYMBOL_GPL(cros_usbpd_unregister_notify);
55
56/**
57 * cros_ec_pd_command - Send a command to the EC.
58 *
59 * @ec_dev: EC device
60 * @command: EC command
61 * @outdata: EC command output data
62 * @outsize: Size of outdata
63 * @indata: EC command input data
64 * @insize: Size of indata
65 *
66 * Return: >= 0 on success, negative error number on failure.
67 */
68static int cros_ec_pd_command(struct cros_ec_device *ec_dev,
69 int command,
70 uint8_t *outdata,
71 int outsize,
72 uint8_t *indata,
73 int insize)
74{
75 struct cros_ec_command *msg;
76 int ret;
77
78 msg = kzalloc(sizeof(*msg) + max(insize, outsize), GFP_KERNEL);
79 if (!msg)
80 return -ENOMEM;
81
82 msg->command = command;
83 msg->outsize = outsize;
84 msg->insize = insize;
85
86 if (outsize)
87 memcpy(msg->data, outdata, outsize);
88
89 ret = cros_ec_cmd_xfer_status(ec_dev, msg);
90 if (ret < 0)
91 goto error;
92
93 if (insize)
94 memcpy(indata, msg->data, insize);
95error:
96 kfree(msg);
97 return ret;
98}
99
100static void cros_usbpd_get_event_and_notify(struct device *dev,
101 struct cros_ec_device *ec_dev)
102{
103 struct ec_response_host_event_status host_event_status;
104 u32 event = 0;
105 int ret;
106
107 /*
108 * We still send a 0 event out to older devices which don't
109 * have the updated device heirarchy.
110 */
111 if (!ec_dev) {
112 dev_dbg(dev,
113 "EC device inaccessible; sending 0 event status.\n");
114 goto send_notify;
115 }
116
117 /* Check for PD host events on EC. */
118 ret = cros_ec_pd_command(ec_dev, EC_CMD_PD_HOST_EVENT_STATUS,
119 NULL, 0,
120 (uint8_t *)&host_event_status,
121 sizeof(host_event_status));
122 if (ret < 0) {
123 dev_warn(dev, "Can't get host event status (err: %d)\n", ret);
124 goto send_notify;
125 }
126
127 event = host_event_status.status;
128
129send_notify:
130 blocking_notifier_call_chain(&cros_usbpd_notifier_list, event, NULL);
131}
132
133#ifdef CONFIG_ACPI
134
135static void cros_usbpd_notify_acpi(acpi_handle device, u32 event, void *data)
136{
137 struct cros_usbpd_notify_data *pdnotify = data;
138
139 cros_usbpd_get_event_and_notify(pdnotify->dev, pdnotify->ec);
140}
141
142static int cros_usbpd_notify_probe_acpi(struct platform_device *pdev)
143{
144 struct cros_usbpd_notify_data *pdnotify;
145 struct device *dev = &pdev->dev;
146 struct acpi_device *adev;
147 struct cros_ec_device *ec_dev;
148 acpi_status status;
149
150 adev = ACPI_COMPANION(dev);
151
152 pdnotify = devm_kzalloc(dev, sizeof(*pdnotify), GFP_KERNEL);
153 if (!pdnotify)
154 return -ENOMEM;
155
156 /* Get the EC device pointer needed to talk to the EC. */
157 ec_dev = dev_get_drvdata(dev->parent);
158 if (!ec_dev) {
159 /*
160 * We continue even for older devices which don't have the
161 * correct device heirarchy, namely, GOOG0003 is a child
162 * of GOOG0004.
163 */
164 dev_warn(dev, "Couldn't get Chrome EC device pointer.\n");
165 }
166
167 pdnotify->dev = dev;
168 pdnotify->ec = ec_dev;
169
170 status = acpi_install_notify_handler(adev->handle,
171 ACPI_ALL_NOTIFY,
172 cros_usbpd_notify_acpi,
173 pdnotify);
174 if (ACPI_FAILURE(status)) {
175 dev_warn(dev, "Failed to register notify handler %08x\n",
176 status);
177 return -EINVAL;
178 }
179
180 return 0;
181}
182
183static int cros_usbpd_notify_remove_acpi(struct platform_device *pdev)
184{
185 struct device *dev = &pdev->dev;
186 struct acpi_device *adev = ACPI_COMPANION(dev);
187
188 acpi_remove_notify_handler(adev->handle, ACPI_ALL_NOTIFY,
189 cros_usbpd_notify_acpi);
190
191 return 0;
192}
193
194static const struct acpi_device_id cros_usbpd_notify_acpi_device_ids[] = {
195 { ACPI_DRV_NAME, 0 },
196 { }
197};
198MODULE_DEVICE_TABLE(acpi, cros_usbpd_notify_acpi_device_ids);
199
200static struct platform_driver cros_usbpd_notify_acpi_driver = {
201 .driver = {
202 .name = DRV_NAME_PLAT_ACPI,
203 .acpi_match_table = cros_usbpd_notify_acpi_device_ids,
204 },
205 .probe = cros_usbpd_notify_probe_acpi,
206 .remove = cros_usbpd_notify_remove_acpi,
207};
208
209#endif /* CONFIG_ACPI */
210
211static int cros_usbpd_notify_plat(struct notifier_block *nb,
212 unsigned long queued_during_suspend,
213 void *data)
214{
215 struct cros_usbpd_notify_data *pdnotify = container_of(nb,
216 struct cros_usbpd_notify_data, nb);
217 struct cros_ec_device *ec_dev = (struct cros_ec_device *)data;
218 u32 host_event = cros_ec_get_host_event(ec_dev);
219
220 if (!host_event)
221 return NOTIFY_DONE;
222
223 if (host_event & (EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) |
224 EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX))) {
225 cros_usbpd_get_event_and_notify(pdnotify->dev, ec_dev);
226 return NOTIFY_OK;
227 }
228 return NOTIFY_DONE;
229}
230
231static int cros_usbpd_notify_probe_plat(struct platform_device *pdev)
232{
233 struct device *dev = &pdev->dev;
234 struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
235 struct cros_usbpd_notify_data *pdnotify;
236 int ret;
237
238 pdnotify = devm_kzalloc(dev, sizeof(*pdnotify), GFP_KERNEL);
239 if (!pdnotify)
240 return -ENOMEM;
241
242 pdnotify->dev = dev;
243 pdnotify->ec = ecdev->ec_dev;
244 pdnotify->nb.notifier_call = cros_usbpd_notify_plat;
245
246 dev_set_drvdata(dev, pdnotify);
247
248 ret = blocking_notifier_chain_register(&ecdev->ec_dev->event_notifier,
249 &pdnotify->nb);
250 if (ret < 0) {
251 dev_err(dev, "Failed to register notifier\n");
252 return ret;
253 }
254
255 return 0;
256}
257
258static int cros_usbpd_notify_remove_plat(struct platform_device *pdev)
259{
260 struct device *dev = &pdev->dev;
261 struct cros_ec_dev *ecdev = dev_get_drvdata(dev->parent);
262 struct cros_usbpd_notify_data *pdnotify =
263 (struct cros_usbpd_notify_data *)dev_get_drvdata(dev);
264
265 blocking_notifier_chain_unregister(&ecdev->ec_dev->event_notifier,
266 &pdnotify->nb);
267
268 return 0;
269}
270
271static struct platform_driver cros_usbpd_notify_plat_driver = {
272 .driver = {
273 .name = DRV_NAME,
274 },
275 .probe = cros_usbpd_notify_probe_plat,
276 .remove = cros_usbpd_notify_remove_plat,
277};
278
279static int __init cros_usbpd_notify_init(void)
280{
281 int ret;
282
283 ret = platform_driver_register(&cros_usbpd_notify_plat_driver);
284 if (ret < 0)
285 return ret;
286
287#ifdef CONFIG_ACPI
288 platform_driver_register(&cros_usbpd_notify_acpi_driver);
289#endif
290 return 0;
291}
292
293static void __exit cros_usbpd_notify_exit(void)
294{
295#ifdef CONFIG_ACPI
296 platform_driver_unregister(&cros_usbpd_notify_acpi_driver);
297#endif
298 platform_driver_unregister(&cros_usbpd_notify_plat_driver);
299}
300
301module_init(cros_usbpd_notify_init);
302module_exit(cros_usbpd_notify_exit);
303
304MODULE_LICENSE("GPL");
305MODULE_DESCRIPTION("ChromeOS power delivery notifier device");
306MODULE_AUTHOR("Jon Flatley <jflat@chromium.org>");
307MODULE_ALIAS("platform:" DRV_NAME);