1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Real time clock driver for DA9055 |
4 | * |
5 | * Copyright(c) 2012 Dialog Semiconductor Ltd. |
6 | * |
7 | * Author: Dajun Dajun Chen <dajun.chen@diasemi.com> |
8 | */ |
9 | |
10 | #include <linux/module.h> |
11 | #include <linux/platform_device.h> |
12 | #include <linux/rtc.h> |
13 | |
14 | #include <linux/mfd/da9055/core.h> |
15 | #include <linux/mfd/da9055/reg.h> |
16 | #include <linux/mfd/da9055/pdata.h> |
17 | |
18 | struct da9055_rtc { |
19 | struct rtc_device *rtc; |
20 | struct da9055 *da9055; |
21 | int alarm_enable; |
22 | }; |
23 | |
24 | static int da9055_rtc_enable_alarm(struct da9055_rtc *rtc, bool enable) |
25 | { |
26 | int ret; |
27 | if (enable) { |
28 | ret = da9055_reg_update(da9055: rtc->da9055, DA9055_REG_ALARM_Y, |
29 | DA9055_RTC_ALM_EN, |
30 | DA9055_RTC_ALM_EN); |
31 | if (ret != 0) |
32 | dev_err(rtc->da9055->dev, "Failed to enable ALM: %d\n" , |
33 | ret); |
34 | rtc->alarm_enable = 1; |
35 | } else { |
36 | ret = da9055_reg_update(da9055: rtc->da9055, DA9055_REG_ALARM_Y, |
37 | DA9055_RTC_ALM_EN, reg_val: 0); |
38 | if (ret != 0) |
39 | dev_err(rtc->da9055->dev, |
40 | "Failed to disable ALM: %d\n" , ret); |
41 | rtc->alarm_enable = 0; |
42 | } |
43 | return ret; |
44 | } |
45 | |
46 | static irqreturn_t da9055_rtc_alm_irq(int irq, void *data) |
47 | { |
48 | struct da9055_rtc *rtc = data; |
49 | |
50 | da9055_rtc_enable_alarm(rtc, enable: 0); |
51 | rtc_update_irq(rtc: rtc->rtc, num: 1, RTC_IRQF | RTC_AF); |
52 | |
53 | return IRQ_HANDLED; |
54 | } |
55 | |
56 | static int da9055_read_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) |
57 | { |
58 | int ret; |
59 | uint8_t v[5]; |
60 | |
61 | ret = da9055_group_read(da9055, DA9055_REG_ALARM_MI, reg_cnt: 5, val: v); |
62 | if (ret != 0) { |
63 | dev_err(da9055->dev, "Failed to group read ALM: %d\n" , ret); |
64 | return ret; |
65 | } |
66 | |
67 | rtc_tm->tm_year = (v[4] & DA9055_RTC_ALM_YEAR) + 100; |
68 | rtc_tm->tm_mon = (v[3] & DA9055_RTC_ALM_MONTH) - 1; |
69 | rtc_tm->tm_mday = v[2] & DA9055_RTC_ALM_DAY; |
70 | rtc_tm->tm_hour = v[1] & DA9055_RTC_ALM_HOUR; |
71 | rtc_tm->tm_min = v[0] & DA9055_RTC_ALM_MIN; |
72 | rtc_tm->tm_sec = 0; |
73 | |
74 | return rtc_valid_tm(tm: rtc_tm); |
75 | } |
76 | |
77 | static int da9055_set_alarm(struct da9055 *da9055, struct rtc_time *rtc_tm) |
78 | { |
79 | int ret; |
80 | uint8_t v[2]; |
81 | |
82 | rtc_tm->tm_year -= 100; |
83 | rtc_tm->tm_mon += 1; |
84 | |
85 | ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MI, |
86 | DA9055_RTC_ALM_MIN, reg_val: rtc_tm->tm_min); |
87 | if (ret != 0) { |
88 | dev_err(da9055->dev, "Failed to write ALRM MIN: %d\n" , ret); |
89 | return ret; |
90 | } |
91 | |
92 | v[0] = rtc_tm->tm_hour; |
93 | v[1] = rtc_tm->tm_mday; |
94 | |
95 | ret = da9055_group_write(da9055, DA9055_REG_ALARM_H, reg_cnt: 2, val: v); |
96 | if (ret < 0) |
97 | return ret; |
98 | |
99 | ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, |
100 | DA9055_RTC_ALM_MONTH, reg_val: rtc_tm->tm_mon); |
101 | if (ret < 0) |
102 | dev_err(da9055->dev, "Failed to write ALM Month:%d\n" , ret); |
103 | |
104 | ret = da9055_reg_update(da9055, DA9055_REG_ALARM_Y, |
105 | DA9055_RTC_ALM_YEAR, reg_val: rtc_tm->tm_year); |
106 | if (ret < 0) |
107 | dev_err(da9055->dev, "Failed to write ALM Year:%d\n" , ret); |
108 | |
109 | return ret; |
110 | } |
111 | |
112 | static int da9055_rtc_get_alarm_status(struct da9055 *da9055) |
113 | { |
114 | int ret; |
115 | |
116 | ret = da9055_reg_read(da9055, DA9055_REG_ALARM_Y); |
117 | if (ret < 0) { |
118 | dev_err(da9055->dev, "Failed to read ALM: %d\n" , ret); |
119 | return ret; |
120 | } |
121 | ret &= DA9055_RTC_ALM_EN; |
122 | return (ret > 0) ? 1 : 0; |
123 | } |
124 | |
125 | static int da9055_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm) |
126 | { |
127 | struct da9055_rtc *rtc = dev_get_drvdata(dev); |
128 | uint8_t v[6]; |
129 | int ret; |
130 | |
131 | ret = da9055_reg_read(da9055: rtc->da9055, DA9055_REG_COUNT_S); |
132 | if (ret < 0) |
133 | return ret; |
134 | |
135 | /* |
136 | * Registers are only valid when RTC_READ |
137 | * status bit is asserted |
138 | */ |
139 | if (!(ret & DA9055_RTC_READ)) |
140 | return -EBUSY; |
141 | |
142 | ret = da9055_group_read(da9055: rtc->da9055, DA9055_REG_COUNT_S, reg_cnt: 6, val: v); |
143 | if (ret < 0) { |
144 | dev_err(rtc->da9055->dev, "Failed to read RTC time : %d\n" , |
145 | ret); |
146 | return ret; |
147 | } |
148 | |
149 | rtc_tm->tm_year = (v[5] & DA9055_RTC_YEAR) + 100; |
150 | rtc_tm->tm_mon = (v[4] & DA9055_RTC_MONTH) - 1; |
151 | rtc_tm->tm_mday = v[3] & DA9055_RTC_DAY; |
152 | rtc_tm->tm_hour = v[2] & DA9055_RTC_HOUR; |
153 | rtc_tm->tm_min = v[1] & DA9055_RTC_MIN; |
154 | rtc_tm->tm_sec = v[0] & DA9055_RTC_SEC; |
155 | |
156 | return 0; |
157 | } |
158 | |
159 | static int da9055_rtc_set_time(struct device *dev, struct rtc_time *tm) |
160 | { |
161 | struct da9055_rtc *rtc; |
162 | uint8_t v[6]; |
163 | |
164 | rtc = dev_get_drvdata(dev); |
165 | |
166 | v[0] = tm->tm_sec; |
167 | v[1] = tm->tm_min; |
168 | v[2] = tm->tm_hour; |
169 | v[3] = tm->tm_mday; |
170 | v[4] = tm->tm_mon + 1; |
171 | v[5] = tm->tm_year - 100; |
172 | |
173 | return da9055_group_write(da9055: rtc->da9055, DA9055_REG_COUNT_S, reg_cnt: 6, val: v); |
174 | } |
175 | |
176 | static int da9055_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
177 | { |
178 | int ret; |
179 | struct rtc_time *tm = &alrm->time; |
180 | struct da9055_rtc *rtc = dev_get_drvdata(dev); |
181 | |
182 | ret = da9055_read_alarm(da9055: rtc->da9055, rtc_tm: tm); |
183 | |
184 | if (ret) |
185 | return ret; |
186 | |
187 | alrm->enabled = da9055_rtc_get_alarm_status(da9055: rtc->da9055); |
188 | |
189 | return 0; |
190 | } |
191 | |
192 | static int da9055_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) |
193 | { |
194 | int ret; |
195 | struct rtc_time *tm = &alrm->time; |
196 | struct da9055_rtc *rtc = dev_get_drvdata(dev); |
197 | |
198 | ret = da9055_rtc_enable_alarm(rtc, enable: 0); |
199 | if (ret < 0) |
200 | return ret; |
201 | |
202 | ret = da9055_set_alarm(da9055: rtc->da9055, rtc_tm: tm); |
203 | if (ret) |
204 | return ret; |
205 | |
206 | ret = da9055_rtc_enable_alarm(rtc, enable: 1); |
207 | |
208 | return ret; |
209 | } |
210 | |
211 | static int da9055_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) |
212 | { |
213 | struct da9055_rtc *rtc = dev_get_drvdata(dev); |
214 | |
215 | return da9055_rtc_enable_alarm(rtc, enable: enabled); |
216 | } |
217 | |
218 | static const struct rtc_class_ops da9055_rtc_ops = { |
219 | .read_time = da9055_rtc_read_time, |
220 | .set_time = da9055_rtc_set_time, |
221 | .read_alarm = da9055_rtc_read_alarm, |
222 | .set_alarm = da9055_rtc_set_alarm, |
223 | .alarm_irq_enable = da9055_rtc_alarm_irq_enable, |
224 | }; |
225 | |
226 | static int da9055_rtc_device_init(struct da9055 *da9055, |
227 | struct da9055_pdata *pdata) |
228 | { |
229 | int ret; |
230 | |
231 | /* Enable RTC and the internal Crystal */ |
232 | ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, |
233 | DA9055_RTC_EN, DA9055_RTC_EN); |
234 | if (ret < 0) |
235 | return ret; |
236 | ret = da9055_reg_update(da9055, DA9055_REG_EN_32K, |
237 | DA9055_CRYSTAL_EN, DA9055_CRYSTAL_EN); |
238 | if (ret < 0) |
239 | return ret; |
240 | |
241 | /* Enable RTC in Power Down mode */ |
242 | ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, |
243 | DA9055_RTC_MODE_PD, DA9055_RTC_MODE_PD); |
244 | if (ret < 0) |
245 | return ret; |
246 | |
247 | /* Enable RTC in Reset mode */ |
248 | if (pdata && pdata->reset_enable) { |
249 | ret = da9055_reg_update(da9055, DA9055_REG_CONTROL_B, |
250 | DA9055_RTC_MODE_SD, |
251 | DA9055_RTC_MODE_SD << |
252 | DA9055_RTC_MODE_SD_SHIFT); |
253 | if (ret < 0) |
254 | return ret; |
255 | } |
256 | |
257 | /* Disable the RTC TICK ALM */ |
258 | ret = da9055_reg_update(da9055, DA9055_REG_ALARM_MO, |
259 | DA9055_RTC_TICK_WAKE_MASK, reg_val: 0); |
260 | if (ret < 0) |
261 | return ret; |
262 | |
263 | return 0; |
264 | } |
265 | |
266 | static int da9055_rtc_probe(struct platform_device *pdev) |
267 | { |
268 | struct da9055_rtc *rtc; |
269 | struct da9055_pdata *pdata = NULL; |
270 | int ret, alm_irq; |
271 | |
272 | rtc = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct da9055_rtc), GFP_KERNEL); |
273 | if (!rtc) |
274 | return -ENOMEM; |
275 | |
276 | rtc->da9055 = dev_get_drvdata(dev: pdev->dev.parent); |
277 | pdata = dev_get_platdata(dev: rtc->da9055->dev); |
278 | platform_set_drvdata(pdev, data: rtc); |
279 | |
280 | ret = da9055_rtc_device_init(da9055: rtc->da9055, pdata); |
281 | if (ret < 0) |
282 | goto err_rtc; |
283 | |
284 | ret = da9055_reg_read(da9055: rtc->da9055, DA9055_REG_ALARM_Y); |
285 | if (ret < 0) |
286 | goto err_rtc; |
287 | |
288 | if (ret & DA9055_RTC_ALM_EN) |
289 | rtc->alarm_enable = 1; |
290 | |
291 | device_init_wakeup(dev: &pdev->dev, enable: 1); |
292 | |
293 | rtc->rtc = devm_rtc_device_register(dev: &pdev->dev, name: pdev->name, |
294 | ops: &da9055_rtc_ops, THIS_MODULE); |
295 | if (IS_ERR(ptr: rtc->rtc)) { |
296 | ret = PTR_ERR(ptr: rtc->rtc); |
297 | goto err_rtc; |
298 | } |
299 | |
300 | alm_irq = platform_get_irq_byname(pdev, "ALM" ); |
301 | if (alm_irq < 0) |
302 | return alm_irq; |
303 | |
304 | ret = devm_request_threaded_irq(dev: &pdev->dev, irq: alm_irq, NULL, |
305 | thread_fn: da9055_rtc_alm_irq, |
306 | IRQF_TRIGGER_HIGH | IRQF_ONESHOT, |
307 | devname: "ALM" , dev_id: rtc); |
308 | if (ret != 0) |
309 | dev_err(rtc->da9055->dev, "irq registration failed: %d\n" , ret); |
310 | |
311 | err_rtc: |
312 | return ret; |
313 | |
314 | } |
315 | |
316 | #ifdef CONFIG_PM |
317 | /* Turn off the alarm if it should not be a wake source. */ |
318 | static int da9055_rtc_suspend(struct device *dev) |
319 | { |
320 | struct platform_device *pdev = to_platform_device(dev); |
321 | struct da9055_rtc *rtc = dev_get_drvdata(dev: &pdev->dev); |
322 | int ret; |
323 | |
324 | if (!device_may_wakeup(dev: &pdev->dev)) { |
325 | /* Disable the ALM IRQ */ |
326 | ret = da9055_rtc_enable_alarm(rtc, enable: 0); |
327 | if (ret < 0) |
328 | dev_err(&pdev->dev, "Failed to disable RTC ALM\n" ); |
329 | } |
330 | |
331 | return 0; |
332 | } |
333 | |
334 | /* Enable the alarm if it should be enabled (in case it was disabled to |
335 | * prevent use as a wake source). |
336 | */ |
337 | static int da9055_rtc_resume(struct device *dev) |
338 | { |
339 | struct platform_device *pdev = to_platform_device(dev); |
340 | struct da9055_rtc *rtc = dev_get_drvdata(dev: &pdev->dev); |
341 | int ret; |
342 | |
343 | if (!device_may_wakeup(dev: &pdev->dev)) { |
344 | if (rtc->alarm_enable) { |
345 | ret = da9055_rtc_enable_alarm(rtc, enable: 1); |
346 | if (ret < 0) |
347 | dev_err(&pdev->dev, |
348 | "Failed to restart RTC ALM\n" ); |
349 | } |
350 | } |
351 | |
352 | return 0; |
353 | } |
354 | |
355 | /* Unconditionally disable the alarm */ |
356 | static int da9055_rtc_freeze(struct device *dev) |
357 | { |
358 | struct platform_device *pdev = to_platform_device(dev); |
359 | struct da9055_rtc *rtc = dev_get_drvdata(dev: &pdev->dev); |
360 | int ret; |
361 | |
362 | ret = da9055_rtc_enable_alarm(rtc, enable: 0); |
363 | if (ret < 0) |
364 | dev_err(&pdev->dev, "Failed to freeze RTC ALMs\n" ); |
365 | |
366 | return 0; |
367 | |
368 | } |
369 | #else |
370 | #define da9055_rtc_suspend NULL |
371 | #define da9055_rtc_resume NULL |
372 | #define da9055_rtc_freeze NULL |
373 | #endif |
374 | |
375 | static const struct dev_pm_ops da9055_rtc_pm_ops = { |
376 | .suspend = da9055_rtc_suspend, |
377 | .resume = da9055_rtc_resume, |
378 | |
379 | .freeze = da9055_rtc_freeze, |
380 | .thaw = da9055_rtc_resume, |
381 | .restore = da9055_rtc_resume, |
382 | |
383 | .poweroff = da9055_rtc_suspend, |
384 | }; |
385 | |
386 | static struct platform_driver da9055_rtc_driver = { |
387 | .probe = da9055_rtc_probe, |
388 | .driver = { |
389 | .name = "da9055-rtc" , |
390 | .pm = &da9055_rtc_pm_ops, |
391 | }, |
392 | }; |
393 | |
394 | module_platform_driver(da9055_rtc_driver); |
395 | |
396 | MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>" ); |
397 | MODULE_DESCRIPTION("RTC driver for Dialog DA9055 PMIC" ); |
398 | MODULE_LICENSE("GPL" ); |
399 | MODULE_ALIAS("platform:da9055-rtc" ); |
400 | |