This source file includes following definitions.
- cros_ec_rtc_get
- cros_ec_rtc_set
- cros_ec_rtc_read_time
- cros_ec_rtc_set_time
- cros_ec_rtc_read_alarm
- cros_ec_rtc_set_alarm
- cros_ec_rtc_alarm_irq_enable
- cros_ec_rtc_event
- cros_ec_rtc_suspend
- cros_ec_rtc_resume
- cros_ec_rtc_probe
- cros_ec_rtc_remove
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6
7 #include <linux/kernel.h>
8 #include <linux/mfd/cros_ec.h>
9 #include <linux/module.h>
10 #include <linux/platform_data/cros_ec_commands.h>
11 #include <linux/platform_data/cros_ec_proto.h>
12 #include <linux/platform_device.h>
13 #include <linux/rtc.h>
14 #include <linux/slab.h>
15
16 #define DRV_NAME "cros-ec-rtc"
17
18
19
20
21
22
23
24
25
26 struct cros_ec_rtc {
27 struct cros_ec_device *cros_ec;
28 struct rtc_device *rtc;
29 struct notifier_block notifier;
30 u32 saved_alarm;
31 };
32
33 static int cros_ec_rtc_get(struct cros_ec_device *cros_ec, u32 command,
34 u32 *response)
35 {
36 int ret;
37 struct {
38 struct cros_ec_command msg;
39 struct ec_response_rtc data;
40 } __packed msg;
41
42 memset(&msg, 0, sizeof(msg));
43 msg.msg.command = command;
44 msg.msg.insize = sizeof(msg.data);
45
46 ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
47 if (ret < 0) {
48 dev_err(cros_ec->dev,
49 "error getting %s from EC: %d\n",
50 command == EC_CMD_RTC_GET_VALUE ? "time" : "alarm",
51 ret);
52 return ret;
53 }
54
55 *response = msg.data.time;
56
57 return 0;
58 }
59
60 static int cros_ec_rtc_set(struct cros_ec_device *cros_ec, u32 command,
61 u32 param)
62 {
63 int ret = 0;
64 struct {
65 struct cros_ec_command msg;
66 struct ec_response_rtc data;
67 } __packed msg;
68
69 memset(&msg, 0, sizeof(msg));
70 msg.msg.command = command;
71 msg.msg.outsize = sizeof(msg.data);
72 msg.data.time = param;
73
74 ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
75 if (ret < 0) {
76 dev_err(cros_ec->dev, "error setting %s on EC: %d\n",
77 command == EC_CMD_RTC_SET_VALUE ? "time" : "alarm",
78 ret);
79 return ret;
80 }
81
82 return 0;
83 }
84
85
86 static int cros_ec_rtc_read_time(struct device *dev, struct rtc_time *tm)
87 {
88 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
89 struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
90 int ret;
91 u32 time;
92
93 ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, &time);
94 if (ret) {
95 dev_err(dev, "error getting time: %d\n", ret);
96 return ret;
97 }
98
99 rtc_time64_to_tm(time, tm);
100
101 return 0;
102 }
103
104
105 static int cros_ec_rtc_set_time(struct device *dev, struct rtc_time *tm)
106 {
107 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
108 struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
109 int ret;
110 time64_t time;
111
112 time = rtc_tm_to_time64(tm);
113 if (time < 0 || time > U32_MAX)
114 return -EINVAL;
115
116 ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_VALUE, (u32)time);
117 if (ret < 0) {
118 dev_err(dev, "error setting time: %d\n", ret);
119 return ret;
120 }
121
122 return 0;
123 }
124
125
126 static int cros_ec_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
127 {
128 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
129 struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
130 int ret;
131 u32 current_time, alarm_offset;
132
133
134
135
136
137
138 ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, ¤t_time);
139 if (ret < 0) {
140 dev_err(dev, "error getting time: %d\n", ret);
141 return ret;
142 }
143
144 ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_ALARM, &alarm_offset);
145 if (ret < 0) {
146 dev_err(dev, "error getting alarm: %d\n", ret);
147 return ret;
148 }
149
150 rtc_time64_to_tm(current_time + alarm_offset, &alrm->time);
151
152 return 0;
153 }
154
155
156 static int cros_ec_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
157 {
158 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
159 struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
160 int ret;
161 time64_t alarm_time;
162 u32 current_time, alarm_offset;
163
164
165
166
167
168
169
170 ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, ¤t_time);
171 if (ret < 0) {
172 dev_err(dev, "error getting time: %d\n", ret);
173 return ret;
174 }
175
176 alarm_time = rtc_tm_to_time64(&alrm->time);
177
178 if (alarm_time < 0 || alarm_time > U32_MAX)
179 return -EINVAL;
180
181 if (!alrm->enabled) {
182
183
184
185
186 alarm_offset = EC_RTC_ALARM_CLEAR;
187 cros_ec_rtc->saved_alarm = (u32)alarm_time;
188 } else {
189
190 if ((u32)alarm_time <= current_time)
191 return -ETIME;
192
193 alarm_offset = (u32)alarm_time - current_time;
194 }
195
196 ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM, alarm_offset);
197 if (ret < 0) {
198 dev_err(dev, "error setting alarm: %d\n", ret);
199 return ret;
200 }
201
202 return 0;
203 }
204
205 static int cros_ec_rtc_alarm_irq_enable(struct device *dev,
206 unsigned int enabled)
207 {
208 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
209 struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
210 int ret;
211 u32 current_time, alarm_offset, alarm_value;
212
213 ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, ¤t_time);
214 if (ret < 0) {
215 dev_err(dev, "error getting time: %d\n", ret);
216 return ret;
217 }
218
219 if (enabled) {
220
221 if (cros_ec_rtc->saved_alarm < current_time)
222 alarm_offset = EC_RTC_ALARM_CLEAR;
223 else
224 alarm_offset = cros_ec_rtc->saved_alarm - current_time;
225
226 ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM,
227 alarm_offset);
228 if (ret < 0) {
229 dev_err(dev, "error restoring alarm: %d\n", ret);
230 return ret;
231 }
232 } else {
233
234 ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_ALARM,
235 &alarm_offset);
236 if (ret < 0) {
237 dev_err(dev, "error saving alarm: %d\n", ret);
238 return ret;
239 }
240
241 alarm_value = current_time + alarm_offset;
242
243
244
245
246
247
248 if (alarm_value < current_time)
249 cros_ec_rtc->saved_alarm = EC_RTC_ALARM_CLEAR;
250 else
251 cros_ec_rtc->saved_alarm = alarm_value;
252
253 alarm_offset = EC_RTC_ALARM_CLEAR;
254 ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM,
255 alarm_offset);
256 if (ret < 0) {
257 dev_err(dev, "error disabling alarm: %d\n", ret);
258 return ret;
259 }
260 }
261
262 return 0;
263 }
264
265 static int cros_ec_rtc_event(struct notifier_block *nb,
266 unsigned long queued_during_suspend,
267 void *_notify)
268 {
269 struct cros_ec_rtc *cros_ec_rtc;
270 struct rtc_device *rtc;
271 struct cros_ec_device *cros_ec;
272 u32 host_event;
273
274 cros_ec_rtc = container_of(nb, struct cros_ec_rtc, notifier);
275 rtc = cros_ec_rtc->rtc;
276 cros_ec = cros_ec_rtc->cros_ec;
277
278 host_event = cros_ec_get_host_event(cros_ec);
279 if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_RTC)) {
280 rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
281 return NOTIFY_OK;
282 } else {
283 return NOTIFY_DONE;
284 }
285 }
286
287 static const struct rtc_class_ops cros_ec_rtc_ops = {
288 .read_time = cros_ec_rtc_read_time,
289 .set_time = cros_ec_rtc_set_time,
290 .read_alarm = cros_ec_rtc_read_alarm,
291 .set_alarm = cros_ec_rtc_set_alarm,
292 .alarm_irq_enable = cros_ec_rtc_alarm_irq_enable,
293 };
294
295 #ifdef CONFIG_PM_SLEEP
296 static int cros_ec_rtc_suspend(struct device *dev)
297 {
298 struct platform_device *pdev = to_platform_device(dev);
299 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(&pdev->dev);
300
301 if (device_may_wakeup(dev))
302 return enable_irq_wake(cros_ec_rtc->cros_ec->irq);
303
304 return 0;
305 }
306
307 static int cros_ec_rtc_resume(struct device *dev)
308 {
309 struct platform_device *pdev = to_platform_device(dev);
310 struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(&pdev->dev);
311
312 if (device_may_wakeup(dev))
313 return disable_irq_wake(cros_ec_rtc->cros_ec->irq);
314
315 return 0;
316 }
317 #endif
318
319 static SIMPLE_DEV_PM_OPS(cros_ec_rtc_pm_ops, cros_ec_rtc_suspend,
320 cros_ec_rtc_resume);
321
322 static int cros_ec_rtc_probe(struct platform_device *pdev)
323 {
324 struct cros_ec_dev *ec_dev = dev_get_drvdata(pdev->dev.parent);
325 struct cros_ec_device *cros_ec = ec_dev->ec_dev;
326 struct cros_ec_rtc *cros_ec_rtc;
327 struct rtc_time tm;
328 int ret;
329
330 cros_ec_rtc = devm_kzalloc(&pdev->dev, sizeof(*cros_ec_rtc),
331 GFP_KERNEL);
332 if (!cros_ec_rtc)
333 return -ENOMEM;
334
335 platform_set_drvdata(pdev, cros_ec_rtc);
336 cros_ec_rtc->cros_ec = cros_ec;
337
338
339 ret = cros_ec_rtc_read_time(&pdev->dev, &tm);
340 if (ret) {
341 dev_err(&pdev->dev, "failed to read RTC time\n");
342 return ret;
343 }
344
345 ret = device_init_wakeup(&pdev->dev, 1);
346 if (ret) {
347 dev_err(&pdev->dev, "failed to initialize wakeup\n");
348 return ret;
349 }
350
351 cros_ec_rtc->rtc = devm_rtc_device_register(&pdev->dev, DRV_NAME,
352 &cros_ec_rtc_ops,
353 THIS_MODULE);
354 if (IS_ERR(cros_ec_rtc->rtc)) {
355 ret = PTR_ERR(cros_ec_rtc->rtc);
356 dev_err(&pdev->dev, "failed to register rtc device\n");
357 return ret;
358 }
359
360
361 cros_ec_rtc->notifier.notifier_call = cros_ec_rtc_event;
362 ret = blocking_notifier_chain_register(&cros_ec->event_notifier,
363 &cros_ec_rtc->notifier);
364 if (ret) {
365 dev_err(&pdev->dev, "failed to register notifier\n");
366 return ret;
367 }
368
369 return 0;
370 }
371
372 static int cros_ec_rtc_remove(struct platform_device *pdev)
373 {
374 struct cros_ec_rtc *cros_ec_rtc = platform_get_drvdata(pdev);
375 struct device *dev = &pdev->dev;
376 int ret;
377
378 ret = blocking_notifier_chain_unregister(
379 &cros_ec_rtc->cros_ec->event_notifier,
380 &cros_ec_rtc->notifier);
381 if (ret) {
382 dev_err(dev, "failed to unregister notifier\n");
383 return ret;
384 }
385
386 return 0;
387 }
388
389 static struct platform_driver cros_ec_rtc_driver = {
390 .probe = cros_ec_rtc_probe,
391 .remove = cros_ec_rtc_remove,
392 .driver = {
393 .name = DRV_NAME,
394 .pm = &cros_ec_rtc_pm_ops,
395 },
396 };
397
398 module_platform_driver(cros_ec_rtc_driver);
399
400 MODULE_DESCRIPTION("RTC driver for Chrome OS ECs");
401 MODULE_AUTHOR("Stephen Barber <smbarber@chromium.org>");
402 MODULE_LICENSE("GPL v2");
403 MODULE_ALIAS("platform:" DRV_NAME);