1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | // |
3 | // Copyright (C) 2018 ROHM Semiconductors |
4 | // |
5 | // RTC driver for ROHM BD71828 and BD71815 PMIC |
6 | |
7 | #include <linux/bcd.h> |
8 | #include <linux/mfd/rohm-bd71815.h> |
9 | #include <linux/mfd/rohm-bd71828.h> |
10 | #include <linux/module.h> |
11 | #include <linux/of.h> |
12 | #include <linux/platform_device.h> |
13 | #include <linux/regmap.h> |
14 | #include <linux/rtc.h> |
15 | |
16 | /* |
17 | * On BD71828 and BD71815 the ALM0 MASK is 14 bytes after the ALM0 |
18 | * block start |
19 | */ |
20 | #define BD718XX_ALM_EN_OFFSET 14 |
21 | |
22 | /* |
23 | * We read regs RTC_SEC => RTC_YEAR |
24 | * this struct is ordered according to chip registers. |
25 | * Keep it u8 only (or packed) to avoid padding issues. |
26 | */ |
27 | struct bd70528_rtc_day { |
28 | u8 sec; |
29 | u8 min; |
30 | u8 hour; |
31 | } __packed; |
32 | |
33 | struct bd70528_rtc_data { |
34 | struct bd70528_rtc_day time; |
35 | u8 week; |
36 | u8 day; |
37 | u8 month; |
38 | u8 year; |
39 | } __packed; |
40 | |
41 | struct bd71828_rtc_alm { |
42 | struct bd70528_rtc_data alm0; |
43 | struct bd70528_rtc_data alm1; |
44 | u8 alm_mask; |
45 | u8 alm1_mask; |
46 | } __packed; |
47 | |
48 | struct bd70528_rtc { |
49 | struct rohm_regmap_dev *parent; |
50 | struct regmap *regmap; |
51 | struct device *dev; |
52 | u8 reg_time_start; |
53 | u8 bd718xx_alm_block_start; |
54 | }; |
55 | |
56 | static inline void tmday2rtc(struct rtc_time *t, struct bd70528_rtc_day *d) |
57 | { |
58 | d->sec &= ~BD70528_MASK_RTC_SEC; |
59 | d->min &= ~BD70528_MASK_RTC_MINUTE; |
60 | d->hour &= ~BD70528_MASK_RTC_HOUR; |
61 | d->sec |= bin2bcd(t->tm_sec); |
62 | d->min |= bin2bcd(t->tm_min); |
63 | d->hour |= bin2bcd(t->tm_hour); |
64 | } |
65 | |
66 | static inline void tm2rtc(struct rtc_time *t, struct bd70528_rtc_data *r) |
67 | { |
68 | r->day &= ~BD70528_MASK_RTC_DAY; |
69 | r->week &= ~BD70528_MASK_RTC_WEEK; |
70 | r->month &= ~BD70528_MASK_RTC_MONTH; |
71 | /* |
72 | * PM and 24H bits are not used by Wake - thus we clear them |
73 | * here and not in tmday2rtc() which is also used by wake. |
74 | */ |
75 | r->time.hour &= ~(BD70528_MASK_RTC_HOUR_PM | BD70528_MASK_RTC_HOUR_24H); |
76 | |
77 | tmday2rtc(t, d: &r->time); |
78 | /* |
79 | * We do always set time in 24H mode. |
80 | */ |
81 | r->time.hour |= BD70528_MASK_RTC_HOUR_24H; |
82 | r->day |= bin2bcd(t->tm_mday); |
83 | r->week |= bin2bcd(t->tm_wday); |
84 | r->month |= bin2bcd(t->tm_mon + 1); |
85 | r->year = bin2bcd(t->tm_year - 100); |
86 | } |
87 | |
88 | static inline void rtc2tm(struct bd70528_rtc_data *r, struct rtc_time *t) |
89 | { |
90 | t->tm_sec = bcd2bin(r->time.sec & BD70528_MASK_RTC_SEC); |
91 | t->tm_min = bcd2bin(r->time.min & BD70528_MASK_RTC_MINUTE); |
92 | t->tm_hour = bcd2bin(r->time.hour & BD70528_MASK_RTC_HOUR); |
93 | /* |
94 | * If RTC is in 12H mode, then bit BD70528_MASK_RTC_HOUR_PM |
95 | * is not BCD value but tells whether it is AM or PM |
96 | */ |
97 | if (!(r->time.hour & BD70528_MASK_RTC_HOUR_24H)) { |
98 | t->tm_hour %= 12; |
99 | if (r->time.hour & BD70528_MASK_RTC_HOUR_PM) |
100 | t->tm_hour += 12; |
101 | } |
102 | t->tm_mday = bcd2bin(r->day & BD70528_MASK_RTC_DAY); |
103 | t->tm_mon = bcd2bin(r->month & BD70528_MASK_RTC_MONTH) - 1; |
104 | t->tm_year = 100 + bcd2bin(r->year & BD70528_MASK_RTC_YEAR); |
105 | t->tm_wday = bcd2bin(r->week & BD70528_MASK_RTC_WEEK); |
106 | } |
107 | |
108 | static int bd71828_set_alarm(struct device *dev, struct rtc_wkalrm *a) |
109 | { |
110 | int ret; |
111 | struct bd71828_rtc_alm alm; |
112 | struct bd70528_rtc *r = dev_get_drvdata(dev); |
113 | |
114 | ret = regmap_bulk_read(map: r->regmap, reg: r->bd718xx_alm_block_start, val: &alm, |
115 | val_count: sizeof(alm)); |
116 | if (ret) { |
117 | dev_err(dev, "Failed to read alarm regs\n" ); |
118 | return ret; |
119 | } |
120 | |
121 | tm2rtc(t: &a->time, r: &alm.alm0); |
122 | |
123 | if (!a->enabled) |
124 | alm.alm_mask &= ~BD70528_MASK_ALM_EN; |
125 | else |
126 | alm.alm_mask |= BD70528_MASK_ALM_EN; |
127 | |
128 | ret = regmap_bulk_write(map: r->regmap, reg: r->bd718xx_alm_block_start, val: &alm, |
129 | val_count: sizeof(alm)); |
130 | if (ret) |
131 | dev_err(dev, "Failed to set alarm time\n" ); |
132 | |
133 | return ret; |
134 | |
135 | } |
136 | |
137 | static int bd71828_read_alarm(struct device *dev, struct rtc_wkalrm *a) |
138 | { |
139 | int ret; |
140 | struct bd71828_rtc_alm alm; |
141 | struct bd70528_rtc *r = dev_get_drvdata(dev); |
142 | |
143 | ret = regmap_bulk_read(map: r->regmap, reg: r->bd718xx_alm_block_start, val: &alm, |
144 | val_count: sizeof(alm)); |
145 | if (ret) { |
146 | dev_err(dev, "Failed to read alarm regs\n" ); |
147 | return ret; |
148 | } |
149 | |
150 | rtc2tm(r: &alm.alm0, t: &a->time); |
151 | a->time.tm_mday = -1; |
152 | a->time.tm_mon = -1; |
153 | a->time.tm_year = -1; |
154 | a->enabled = !!(alm.alm_mask & BD70528_MASK_ALM_EN); |
155 | a->pending = 0; |
156 | |
157 | return 0; |
158 | } |
159 | |
160 | static int bd71828_set_time(struct device *dev, struct rtc_time *t) |
161 | { |
162 | int ret; |
163 | struct bd70528_rtc_data rtc_data; |
164 | struct bd70528_rtc *r = dev_get_drvdata(dev); |
165 | |
166 | ret = regmap_bulk_read(map: r->regmap, reg: r->reg_time_start, val: &rtc_data, |
167 | val_count: sizeof(rtc_data)); |
168 | if (ret) { |
169 | dev_err(dev, "Failed to read RTC time registers\n" ); |
170 | return ret; |
171 | } |
172 | tm2rtc(t, r: &rtc_data); |
173 | |
174 | ret = regmap_bulk_write(map: r->regmap, reg: r->reg_time_start, val: &rtc_data, |
175 | val_count: sizeof(rtc_data)); |
176 | if (ret) |
177 | dev_err(dev, "Failed to set RTC time\n" ); |
178 | |
179 | return ret; |
180 | } |
181 | |
182 | static int bd70528_get_time(struct device *dev, struct rtc_time *t) |
183 | { |
184 | struct bd70528_rtc *r = dev_get_drvdata(dev); |
185 | struct bd70528_rtc_data rtc_data; |
186 | int ret; |
187 | |
188 | /* read the RTC date and time registers all at once */ |
189 | ret = regmap_bulk_read(map: r->regmap, reg: r->reg_time_start, val: &rtc_data, |
190 | val_count: sizeof(rtc_data)); |
191 | if (ret) { |
192 | dev_err(dev, "Failed to read RTC time (err %d)\n" , ret); |
193 | return ret; |
194 | } |
195 | |
196 | rtc2tm(r: &rtc_data, t); |
197 | |
198 | return 0; |
199 | } |
200 | |
201 | static int bd71828_alm_enable(struct device *dev, unsigned int enabled) |
202 | { |
203 | int ret; |
204 | struct bd70528_rtc *r = dev_get_drvdata(dev); |
205 | unsigned int enableval = BD70528_MASK_ALM_EN; |
206 | |
207 | if (!enabled) |
208 | enableval = 0; |
209 | |
210 | ret = regmap_update_bits(map: r->regmap, reg: r->bd718xx_alm_block_start + |
211 | BD718XX_ALM_EN_OFFSET, BD70528_MASK_ALM_EN, |
212 | val: enableval); |
213 | if (ret) |
214 | dev_err(dev, "Failed to change alarm state\n" ); |
215 | |
216 | return ret; |
217 | } |
218 | |
219 | static const struct rtc_class_ops bd71828_rtc_ops = { |
220 | .read_time = bd70528_get_time, |
221 | .set_time = bd71828_set_time, |
222 | .read_alarm = bd71828_read_alarm, |
223 | .set_alarm = bd71828_set_alarm, |
224 | .alarm_irq_enable = bd71828_alm_enable, |
225 | }; |
226 | |
227 | static irqreturn_t alm_hndlr(int irq, void *data) |
228 | { |
229 | struct rtc_device *rtc = data; |
230 | |
231 | rtc_update_irq(rtc, num: 1, RTC_IRQF | RTC_AF | RTC_PF); |
232 | return IRQ_HANDLED; |
233 | } |
234 | |
235 | static int bd70528_probe(struct platform_device *pdev) |
236 | { |
237 | struct bd70528_rtc *bd_rtc; |
238 | const struct rtc_class_ops *rtc_ops; |
239 | const char *irq_name; |
240 | int ret; |
241 | struct rtc_device *rtc; |
242 | int irq; |
243 | unsigned int hr; |
244 | u8 hour_reg; |
245 | enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data; |
246 | |
247 | bd_rtc = devm_kzalloc(dev: &pdev->dev, size: sizeof(*bd_rtc), GFP_KERNEL); |
248 | if (!bd_rtc) |
249 | return -ENOMEM; |
250 | |
251 | bd_rtc->regmap = dev_get_regmap(dev: pdev->dev.parent, NULL); |
252 | if (!bd_rtc->regmap) { |
253 | dev_err(&pdev->dev, "No regmap\n" ); |
254 | return -EINVAL; |
255 | } |
256 | |
257 | bd_rtc->dev = &pdev->dev; |
258 | rtc_ops = &bd71828_rtc_ops; |
259 | |
260 | switch (chip) { |
261 | case ROHM_CHIP_TYPE_BD71815: |
262 | irq_name = "bd71815-rtc-alm-0" ; |
263 | bd_rtc->reg_time_start = BD71815_REG_RTC_START; |
264 | |
265 | /* |
266 | * See also BD718XX_ALM_EN_OFFSET: |
267 | * This works for BD71828 and BD71815 as they have same offset |
268 | * between ALM0 start and ALM0_MASK. If new ICs are to be |
269 | * added this requires proper check as ALM0_MASK is not located |
270 | * at the end of ALM0 block - but after all ALM blocks so if |
271 | * amount of ALMs differ the offset to enable/disable is likely |
272 | * to be incorrect and enable/disable must be given as own |
273 | * reg address here. |
274 | */ |
275 | bd_rtc->bd718xx_alm_block_start = BD71815_REG_RTC_ALM_START; |
276 | hour_reg = BD71815_REG_HOUR; |
277 | break; |
278 | case ROHM_CHIP_TYPE_BD71828: |
279 | irq_name = "bd71828-rtc-alm-0" ; |
280 | bd_rtc->reg_time_start = BD71828_REG_RTC_START; |
281 | bd_rtc->bd718xx_alm_block_start = BD71828_REG_RTC_ALM_START; |
282 | hour_reg = BD71828_REG_RTC_HOUR; |
283 | break; |
284 | default: |
285 | dev_err(&pdev->dev, "Unknown chip\n" ); |
286 | return -ENOENT; |
287 | } |
288 | |
289 | irq = platform_get_irq_byname(pdev, irq_name); |
290 | |
291 | if (irq < 0) |
292 | return irq; |
293 | |
294 | platform_set_drvdata(pdev, data: bd_rtc); |
295 | |
296 | ret = regmap_read(map: bd_rtc->regmap, reg: hour_reg, val: &hr); |
297 | |
298 | if (ret) { |
299 | dev_err(&pdev->dev, "Failed to reag RTC clock\n" ); |
300 | return ret; |
301 | } |
302 | |
303 | if (!(hr & BD70528_MASK_RTC_HOUR_24H)) { |
304 | struct rtc_time t; |
305 | |
306 | ret = rtc_ops->read_time(&pdev->dev, &t); |
307 | |
308 | if (!ret) |
309 | ret = rtc_ops->set_time(&pdev->dev, &t); |
310 | |
311 | if (ret) { |
312 | dev_err(&pdev->dev, |
313 | "Setting 24H clock for RTC failed\n" ); |
314 | return ret; |
315 | } |
316 | } |
317 | |
318 | device_set_wakeup_capable(dev: &pdev->dev, capable: true); |
319 | device_wakeup_enable(dev: &pdev->dev); |
320 | |
321 | rtc = devm_rtc_allocate_device(dev: &pdev->dev); |
322 | if (IS_ERR(ptr: rtc)) { |
323 | dev_err(&pdev->dev, "RTC device creation failed\n" ); |
324 | return PTR_ERR(ptr: rtc); |
325 | } |
326 | |
327 | rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; |
328 | rtc->range_max = RTC_TIMESTAMP_END_2099; |
329 | rtc->ops = rtc_ops; |
330 | |
331 | /* Request alarm IRQ prior to registerig the RTC */ |
332 | ret = devm_request_threaded_irq(dev: &pdev->dev, irq, NULL, thread_fn: &alm_hndlr, |
333 | IRQF_ONESHOT, devname: "bd70528-rtc" , dev_id: rtc); |
334 | if (ret) |
335 | return ret; |
336 | |
337 | return devm_rtc_register_device(rtc); |
338 | } |
339 | |
340 | static const struct platform_device_id bd718x7_rtc_id[] = { |
341 | { "bd71828-rtc" , ROHM_CHIP_TYPE_BD71828 }, |
342 | { "bd71815-rtc" , ROHM_CHIP_TYPE_BD71815 }, |
343 | { }, |
344 | }; |
345 | MODULE_DEVICE_TABLE(platform, bd718x7_rtc_id); |
346 | |
347 | static struct platform_driver bd70528_rtc = { |
348 | .driver = { |
349 | .name = "bd70528-rtc" |
350 | }, |
351 | .probe = bd70528_probe, |
352 | .id_table = bd718x7_rtc_id, |
353 | }; |
354 | |
355 | module_platform_driver(bd70528_rtc); |
356 | |
357 | MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>" ); |
358 | MODULE_DESCRIPTION("ROHM BD71828 and BD71815 PMIC RTC driver" ); |
359 | MODULE_LICENSE("GPL" ); |
360 | MODULE_ALIAS("platform:bd70528-rtc" ); |
361 | |