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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * pm8xxx RTC driver
4 *
5 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
6 * Copyright (c) 2023, Linaro Limited
7 */
8#include <linux/of.h>
9#include <linux/module.h>
10#include <linux/nvmem-consumer.h>
11#include <linux/init.h>
12#include <linux/rtc.h>
13#include <linux/platform_device.h>
14#include <linux/pm.h>
15#include <linux/pm_wakeirq.h>
16#include <linux/regmap.h>
17#include <linux/slab.h>
18#include <linux/spinlock.h>
19
20#include <linux/unaligned.h>
21
22/* RTC_CTRL register bit fields */
23#define PM8xxx_RTC_ENABLE BIT(7)
24#define PM8xxx_RTC_ALARM_CLEAR BIT(0)
25#define PM8xxx_RTC_ALARM_ENABLE BIT(7)
26
27#define NUM_8_BIT_RTC_REGS 0x4
28
29/**
30 * struct pm8xxx_rtc_regs - describe RTC registers per PMIC versions
31 * @ctrl: address of control register
32 * @write: base address of write registers
33 * @read: base address of read registers
34 * @alarm_ctrl: address of alarm control register
35 * @alarm_ctrl2: address of alarm control2 register
36 * @alarm_rw: base address of alarm read-write registers
37 * @alarm_en: alarm enable mask
38 */
39struct pm8xxx_rtc_regs {
40 unsigned int ctrl;
41 unsigned int write;
42 unsigned int read;
43 unsigned int alarm_ctrl;
44 unsigned int alarm_ctrl2;
45 unsigned int alarm_rw;
46 unsigned int alarm_en;
47};
48
49/**
50 * struct pm8xxx_rtc - RTC driver internal structure
51 * @rtc: RTC device
52 * @regmap: regmap used to access registers
53 * @allow_set_time: whether the time can be set
54 * @alarm_irq: alarm irq number
55 * @regs: register description
56 * @dev: device structure
57 * @nvmem_cell: nvmem cell for offset
58 * @offset: offset from epoch in seconds
59 */
60struct pm8xxx_rtc {
61 struct rtc_device *rtc;
62 struct regmap *regmap;
63 bool allow_set_time;
64 int alarm_irq;
65 const struct pm8xxx_rtc_regs *regs;
66 struct device *dev;
67 struct nvmem_cell *nvmem_cell;
68 u32 offset;
69};
70
71static int pm8xxx_rtc_read_nvmem_offset(struct pm8xxx_rtc *rtc_dd)
72{
73 size_t len;
74 void *buf;
75 int rc;
76
77 buf = nvmem_cell_read(rtc_dd->nvmem_cell, &len);
78 if (IS_ERR(buf)) {
79 rc = PTR_ERR(buf);
80 dev_dbg(rtc_dd->dev, "failed to read nvmem offset: %d\n", rc);
81 return rc;
82 }
83
84 if (len != sizeof(u32)) {
85 dev_dbg(rtc_dd->dev, "unexpected nvmem cell size %zu\n", len);
86 kfree(buf);
87 return -EINVAL;
88 }
89
90 rtc_dd->offset = get_unaligned_le32(buf);
91
92 kfree(buf);
93
94 return 0;
95}
96
97static int pm8xxx_rtc_write_nvmem_offset(struct pm8xxx_rtc *rtc_dd, u32 offset)
98{
99 u8 buf[sizeof(u32)];
100 int rc;
101
102 put_unaligned_le32(offset, buf);
103
104 rc = nvmem_cell_write(rtc_dd->nvmem_cell, buf, sizeof(buf));
105 if (rc < 0) {
106 dev_dbg(rtc_dd->dev, "failed to write nvmem offset: %d\n", rc);
107 return rc;
108 }
109
110 return 0;
111}
112
113static int pm8xxx_rtc_read_offset(struct pm8xxx_rtc *rtc_dd)
114{
115 if (!rtc_dd->nvmem_cell)
116 return 0;
117
118 return pm8xxx_rtc_read_nvmem_offset(rtc_dd);
119}
120
121static int pm8xxx_rtc_read_raw(struct pm8xxx_rtc *rtc_dd, u32 *secs)
122{
123 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
124 u8 value[NUM_8_BIT_RTC_REGS];
125 unsigned int reg;
126 int rc;
127
128 rc = regmap_bulk_read(rtc_dd->regmap, regs->read, value, sizeof(value));
129 if (rc)
130 return rc;
131
132 /*
133 * Read the LSB again and check if there has been a carry over.
134 * If there has, redo the read operation.
135 */
136 rc = regmap_read(rtc_dd->regmap, regs->read, ®);
137 if (rc < 0)
138 return rc;
139
140 if (reg < value[0]) {
141 rc = regmap_bulk_read(rtc_dd->regmap, regs->read, value,
142 sizeof(value));
143 if (rc)
144 return rc;
145 }
146
147 *secs = get_unaligned_le32(value);
148
149 return 0;
150}
151
152static int pm8xxx_rtc_update_offset(struct pm8xxx_rtc *rtc_dd, u32 secs)
153{
154 u32 raw_secs;
155 u32 offset;
156 int rc;
157
158 if (!rtc_dd->nvmem_cell)
159 return -ENODEV;
160
161 rc = pm8xxx_rtc_read_raw(rtc_dd, &raw_secs);
162 if (rc)
163 return rc;
164
165 offset = secs - raw_secs;
166
167 if (offset == rtc_dd->offset)
168 return 0;
169
170 rc = pm8xxx_rtc_write_nvmem_offset(rtc_dd, offset);
171 if (rc)
172 return rc;
173
174 rtc_dd->offset = offset;
175
176 return 0;
177}
178
179/*
180 * Steps to write the RTC registers.
181 * 1. Disable alarm if enabled.
182 * 2. Disable rtc if enabled.
183 * 3. Write 0x00 to LSB.
184 * 4. Write Byte[1], Byte[2], Byte[3] then Byte[0].
185 * 5. Enable rtc if disabled in step 2.
186 * 6. Enable alarm if disabled in step 1.
187 */
188static int __pm8xxx_rtc_set_time(struct pm8xxx_rtc *rtc_dd, u32 secs)
189{
190 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
191 u8 value[NUM_8_BIT_RTC_REGS];
192 bool alarm_enabled;
193 int rc;
194
195 put_unaligned_le32(secs, value);
196
197 rc = regmap_update_bits_check(rtc_dd->regmap, regs->alarm_ctrl,
198 regs->alarm_en, 0, &alarm_enabled);
199 if (rc)
200 return rc;
201
202 /* Disable RTC */
203 rc = regmap_update_bits(rtc_dd->regmap, regs->ctrl, PM8xxx_RTC_ENABLE, 0);
204 if (rc)
205 return rc;
206
207 /* Write 0 to Byte[0] */
208 rc = regmap_write(rtc_dd->regmap, regs->write, 0);
209 if (rc)
210 return rc;
211
212 /* Write Byte[1], Byte[2], Byte[3] */
213 rc = regmap_bulk_write(rtc_dd->regmap, regs->write + 1,
214 &value[1], sizeof(value) - 1);
215 if (rc)
216 return rc;
217
218 /* Write Byte[0] */
219 rc = regmap_write(rtc_dd->regmap, regs->write, value[0]);
220 if (rc)
221 return rc;
222
223 /* Enable RTC */
224 rc = regmap_update_bits(rtc_dd->regmap, regs->ctrl, PM8xxx_RTC_ENABLE,
225 PM8xxx_RTC_ENABLE);
226 if (rc)
227 return rc;
228
229 if (alarm_enabled) {
230 rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl,
231 regs->alarm_en, regs->alarm_en);
232 if (rc)
233 return rc;
234 }
235
236 return 0;
237}
238
239static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
240{
241 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
242 u32 secs;
243 int rc;
244
245 secs = rtc_tm_to_time64(tm);
246
247 if (rtc_dd->allow_set_time)
248 rc = __pm8xxx_rtc_set_time(rtc_dd, secs);
249 else
250 rc = pm8xxx_rtc_update_offset(rtc_dd, secs);
251
252 if (rc)
253 return rc;
254
255 dev_dbg(dev, "set time: %ptRd %ptRt (%u + %u)\n", tm, tm,
256 secs - rtc_dd->offset, rtc_dd->offset);
257 return 0;
258}
259
260static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
261{
262 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
263 u32 secs;
264 int rc;
265
266 rc = pm8xxx_rtc_read_raw(rtc_dd, &secs);
267 if (rc)
268 return rc;
269
270 secs += rtc_dd->offset;
271 rtc_time64_to_tm(secs, tm);
272
273 dev_dbg(dev, "read time: %ptRd %ptRt (%u + %u)\n", tm, tm,
274 secs - rtc_dd->offset, rtc_dd->offset);
275 return 0;
276}
277
278static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
279{
280 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
281 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
282 u8 value[NUM_8_BIT_RTC_REGS];
283 u32 secs;
284 int rc;
285
286 secs = rtc_tm_to_time64(&alarm->time);
287 secs -= rtc_dd->offset;
288 put_unaligned_le32(secs, value);
289
290 rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl,
291 regs->alarm_en, 0);
292 if (rc)
293 return rc;
294
295 rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
296 sizeof(value));
297 if (rc)
298 return rc;
299
300 if (alarm->enabled) {
301 rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl,
302 regs->alarm_en, regs->alarm_en);
303 if (rc)
304 return rc;
305 }
306
307 dev_dbg(dev, "set alarm: %ptRd %ptRt\n", &alarm->time, &alarm->time);
308
309 return 0;
310}
311
312static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
313{
314 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
315 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
316 u8 value[NUM_8_BIT_RTC_REGS];
317 unsigned int ctrl_reg;
318 u32 secs;
319 int rc;
320
321 rc = regmap_bulk_read(rtc_dd->regmap, regs->alarm_rw, value,
322 sizeof(value));
323 if (rc)
324 return rc;
325
326 secs = get_unaligned_le32(value);
327 secs += rtc_dd->offset;
328 rtc_time64_to_tm(secs, &alarm->time);
329
330 rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
331 if (rc)
332 return rc;
333
334 alarm->enabled = !!(ctrl_reg & PM8xxx_RTC_ALARM_ENABLE);
335
336 dev_dbg(dev, "read alarm: %ptRd %ptRt\n", &alarm->time, &alarm->time);
337
338 return 0;
339}
340
341static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
342{
343 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
344 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
345 u8 value[NUM_8_BIT_RTC_REGS] = {0};
346 unsigned int val;
347 int rc;
348
349 if (enable)
350 val = regs->alarm_en;
351 else
352 val = 0;
353
354 rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl,
355 regs->alarm_en, val);
356 if (rc)
357 return rc;
358
359 /* Clear alarm register */
360 if (!enable) {
361 rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
362 sizeof(value));
363 if (rc)
364 return rc;
365 }
366
367 return 0;
368}
369
370static const struct rtc_class_ops pm8xxx_rtc_ops = {
371 .read_time = pm8xxx_rtc_read_time,
372 .set_time = pm8xxx_rtc_set_time,
373 .set_alarm = pm8xxx_rtc_set_alarm,
374 .read_alarm = pm8xxx_rtc_read_alarm,
375 .alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
376};
377
378static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
379{
380 struct pm8xxx_rtc *rtc_dd = dev_id;
381 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
382 int rc;
383
384 rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF);
385
386 /* Disable alarm */
387 rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl,
388 regs->alarm_en, 0);
389 if (rc)
390 return IRQ_NONE;
391
392 /* Clear alarm status */
393 rc = regmap_update_bits(rtc_dd->regmap, regs->alarm_ctrl2,
394 PM8xxx_RTC_ALARM_CLEAR, 0);
395 if (rc)
396 return IRQ_NONE;
397
398 return IRQ_HANDLED;
399}
400
401static int pm8xxx_rtc_enable(struct pm8xxx_rtc *rtc_dd)
402{
403 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
404
405 return regmap_update_bits(rtc_dd->regmap, regs->ctrl, PM8xxx_RTC_ENABLE,
406 PM8xxx_RTC_ENABLE);
407}
408
409static const struct pm8xxx_rtc_regs pm8921_regs = {
410 .ctrl = 0x11d,
411 .write = 0x11f,
412 .read = 0x123,
413 .alarm_rw = 0x127,
414 .alarm_ctrl = 0x11d,
415 .alarm_ctrl2 = 0x11e,
416 .alarm_en = BIT(1),
417};
418
419static const struct pm8xxx_rtc_regs pm8058_regs = {
420 .ctrl = 0x1e8,
421 .write = 0x1ea,
422 .read = 0x1ee,
423 .alarm_rw = 0x1f2,
424 .alarm_ctrl = 0x1e8,
425 .alarm_ctrl2 = 0x1e9,
426 .alarm_en = BIT(1),
427};
428
429static const struct pm8xxx_rtc_regs pm8941_regs = {
430 .ctrl = 0x6046,
431 .write = 0x6040,
432 .read = 0x6048,
433 .alarm_rw = 0x6140,
434 .alarm_ctrl = 0x6146,
435 .alarm_ctrl2 = 0x6148,
436 .alarm_en = BIT(7),
437};
438
439static const struct pm8xxx_rtc_regs pmk8350_regs = {
440 .ctrl = 0x6146,
441 .write = 0x6140,
442 .read = 0x6148,
443 .alarm_rw = 0x6240,
444 .alarm_ctrl = 0x6246,
445 .alarm_ctrl2 = 0x6248,
446 .alarm_en = BIT(7),
447};
448
449static const struct of_device_id pm8xxx_id_table[] = {
450 { .compatible = "qcom,pm8921-rtc", .data = &pm8921_regs },
451 { .compatible = "qcom,pm8058-rtc", .data = &pm8058_regs },
452 { .compatible = "qcom,pm8941-rtc", .data = &pm8941_regs },
453 { .compatible = "qcom,pmk8350-rtc", .data = &pmk8350_regs },
454 { },
455};
456MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
457
458static int pm8xxx_rtc_probe(struct platform_device *pdev)
459{
460 const struct of_device_id *match;
461 struct pm8xxx_rtc *rtc_dd;
462 int rc;
463
464 match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
465 if (!match)
466 return -ENXIO;
467
468 rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
469 if (rtc_dd == NULL)
470 return -ENOMEM;
471
472 rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
473 if (!rtc_dd->regmap)
474 return -ENXIO;
475
476 rtc_dd->alarm_irq = platform_get_irq(pdev, 0);
477 if (rtc_dd->alarm_irq < 0)
478 return -ENXIO;
479
480 rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
481 "allow-set-time");
482
483 rtc_dd->nvmem_cell = devm_nvmem_cell_get(&pdev->dev, "offset");
484 if (IS_ERR(rtc_dd->nvmem_cell)) {
485 rc = PTR_ERR(rtc_dd->nvmem_cell);
486 if (rc != -ENOENT)
487 return rc;
488 rtc_dd->nvmem_cell = NULL;
489 }
490
491 rtc_dd->regs = match->data;
492 rtc_dd->dev = &pdev->dev;
493
494 if (!rtc_dd->allow_set_time) {
495 rc = pm8xxx_rtc_read_offset(rtc_dd);
496 if (rc)
497 return rc;
498 }
499
500 rc = pm8xxx_rtc_enable(rtc_dd);
501 if (rc)
502 return rc;
503
504 platform_set_drvdata(pdev, rtc_dd);
505
506 device_init_wakeup(&pdev->dev, 1);
507
508 rtc_dd->rtc = devm_rtc_allocate_device(&pdev->dev);
509 if (IS_ERR(rtc_dd->rtc))
510 return PTR_ERR(rtc_dd->rtc);
511
512 rtc_dd->rtc->ops = &pm8xxx_rtc_ops;
513 rtc_dd->rtc->range_max = U32_MAX;
514
515 rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->alarm_irq,
516 pm8xxx_alarm_trigger,
517 IRQF_TRIGGER_RISING,
518 "pm8xxx_rtc_alarm", rtc_dd);
519 if (rc < 0)
520 return rc;
521
522 rc = devm_rtc_register_device(rtc_dd->rtc);
523 if (rc)
524 return rc;
525
526 rc = dev_pm_set_wake_irq(&pdev->dev, rtc_dd->alarm_irq);
527 if (rc)
528 return rc;
529
530 return 0;
531}
532
533static void pm8xxx_remove(struct platform_device *pdev)
534{
535 dev_pm_clear_wake_irq(&pdev->dev);
536}
537
538static struct platform_driver pm8xxx_rtc_driver = {
539 .probe = pm8xxx_rtc_probe,
540 .remove = pm8xxx_remove,
541 .driver = {
542 .name = "rtc-pm8xxx",
543 .of_match_table = pm8xxx_id_table,
544 },
545};
546
547module_platform_driver(pm8xxx_rtc_driver);
548
549MODULE_ALIAS("platform:rtc-pm8xxx");
550MODULE_DESCRIPTION("PMIC8xxx RTC driver");
551MODULE_LICENSE("GPL v2");
552MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");
553MODULE_AUTHOR("Johan Hovold <johan@kernel.org>");
1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
3 */
4#include <linux/of.h>
5#include <linux/module.h>
6#include <linux/init.h>
7#include <linux/rtc.h>
8#include <linux/platform_device.h>
9#include <linux/pm.h>
10#include <linux/regmap.h>
11#include <linux/slab.h>
12#include <linux/spinlock.h>
13
14/* RTC Register offsets from RTC CTRL REG */
15#define PM8XXX_ALARM_CTRL_OFFSET 0x01
16#define PM8XXX_RTC_WRITE_OFFSET 0x02
17#define PM8XXX_RTC_READ_OFFSET 0x06
18#define PM8XXX_ALARM_RW_OFFSET 0x0A
19
20/* RTC_CTRL register bit fields */
21#define PM8xxx_RTC_ENABLE BIT(7)
22#define PM8xxx_RTC_ALARM_CLEAR BIT(0)
23
24#define NUM_8_BIT_RTC_REGS 0x4
25
26/**
27 * struct pm8xxx_rtc_regs - describe RTC registers per PMIC versions
28 * @ctrl: base address of control register
29 * @write: base address of write register
30 * @read: base address of read register
31 * @alarm_ctrl: base address of alarm control register
32 * @alarm_ctrl2: base address of alarm control2 register
33 * @alarm_rw: base address of alarm read-write register
34 * @alarm_en: alarm enable mask
35 */
36struct pm8xxx_rtc_regs {
37 unsigned int ctrl;
38 unsigned int write;
39 unsigned int read;
40 unsigned int alarm_ctrl;
41 unsigned int alarm_ctrl2;
42 unsigned int alarm_rw;
43 unsigned int alarm_en;
44};
45
46/**
47 * struct pm8xxx_rtc - rtc driver internal structure
48 * @rtc: rtc device for this driver.
49 * @regmap: regmap used to access RTC registers
50 * @allow_set_time: indicates whether writing to the RTC is allowed
51 * @rtc_alarm_irq: rtc alarm irq number.
52 * @regs: rtc registers description.
53 * @rtc_dev: device structure.
54 * @ctrl_reg_lock: spinlock protecting access to ctrl_reg.
55 */
56struct pm8xxx_rtc {
57 struct rtc_device *rtc;
58 struct regmap *regmap;
59 bool allow_set_time;
60 int rtc_alarm_irq;
61 const struct pm8xxx_rtc_regs *regs;
62 struct device *rtc_dev;
63 spinlock_t ctrl_reg_lock;
64};
65
66/*
67 * Steps to write the RTC registers.
68 * 1. Disable alarm if enabled.
69 * 2. Disable rtc if enabled.
70 * 3. Write 0x00 to LSB.
71 * 4. Write Byte[1], Byte[2], Byte[3] then Byte[0].
72 * 5. Enable rtc if disabled in step 2.
73 * 6. Enable alarm if disabled in step 1.
74 */
75static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
76{
77 int rc, i;
78 unsigned long secs, irq_flags;
79 u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, rtc_disabled = 0;
80 unsigned int ctrl_reg, rtc_ctrl_reg;
81 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
82 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
83
84 if (!rtc_dd->allow_set_time)
85 return -EACCES;
86
87 secs = rtc_tm_to_time64(tm);
88
89 dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs);
90
91 for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
92 value[i] = secs & 0xFF;
93 secs >>= 8;
94 }
95
96 spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
97
98 rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
99 if (rc)
100 goto rtc_rw_fail;
101
102 if (ctrl_reg & regs->alarm_en) {
103 alarm_enabled = 1;
104 ctrl_reg &= ~regs->alarm_en;
105 rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
106 if (rc) {
107 dev_err(dev, "Write to RTC Alarm control register failed\n");
108 goto rtc_rw_fail;
109 }
110 }
111
112 /* Disable RTC H/w before writing on RTC register */
113 rc = regmap_read(rtc_dd->regmap, regs->ctrl, &rtc_ctrl_reg);
114 if (rc)
115 goto rtc_rw_fail;
116
117 if (rtc_ctrl_reg & PM8xxx_RTC_ENABLE) {
118 rtc_disabled = 1;
119 rtc_ctrl_reg &= ~PM8xxx_RTC_ENABLE;
120 rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
121 if (rc) {
122 dev_err(dev, "Write to RTC control register failed\n");
123 goto rtc_rw_fail;
124 }
125 }
126
127 /* Write 0 to Byte[0] */
128 rc = regmap_write(rtc_dd->regmap, regs->write, 0);
129 if (rc) {
130 dev_err(dev, "Write to RTC write data register failed\n");
131 goto rtc_rw_fail;
132 }
133
134 /* Write Byte[1], Byte[2], Byte[3] */
135 rc = regmap_bulk_write(rtc_dd->regmap, regs->write + 1,
136 &value[1], sizeof(value) - 1);
137 if (rc) {
138 dev_err(dev, "Write to RTC write data register failed\n");
139 goto rtc_rw_fail;
140 }
141
142 /* Write Byte[0] */
143 rc = regmap_write(rtc_dd->regmap, regs->write, value[0]);
144 if (rc) {
145 dev_err(dev, "Write to RTC write data register failed\n");
146 goto rtc_rw_fail;
147 }
148
149 /* Enable RTC H/w after writing on RTC register */
150 if (rtc_disabled) {
151 rtc_ctrl_reg |= PM8xxx_RTC_ENABLE;
152 rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg);
153 if (rc) {
154 dev_err(dev, "Write to RTC control register failed\n");
155 goto rtc_rw_fail;
156 }
157 }
158
159 if (alarm_enabled) {
160 ctrl_reg |= regs->alarm_en;
161 rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
162 if (rc) {
163 dev_err(dev, "Write to RTC Alarm control register failed\n");
164 goto rtc_rw_fail;
165 }
166 }
167
168rtc_rw_fail:
169 spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
170
171 return rc;
172}
173
174static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
175{
176 int rc;
177 u8 value[NUM_8_BIT_RTC_REGS];
178 unsigned long secs;
179 unsigned int reg;
180 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
181 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
182
183 rc = regmap_bulk_read(rtc_dd->regmap, regs->read, value, sizeof(value));
184 if (rc) {
185 dev_err(dev, "RTC read data register failed\n");
186 return rc;
187 }
188
189 /*
190 * Read the LSB again and check if there has been a carry over.
191 * If there is, redo the read operation.
192 */
193 rc = regmap_read(rtc_dd->regmap, regs->read, ®);
194 if (rc < 0) {
195 dev_err(dev, "RTC read data register failed\n");
196 return rc;
197 }
198
199 if (unlikely(reg < value[0])) {
200 rc = regmap_bulk_read(rtc_dd->regmap, regs->read,
201 value, sizeof(value));
202 if (rc) {
203 dev_err(dev, "RTC read data register failed\n");
204 return rc;
205 }
206 }
207
208 secs = value[0] | (value[1] << 8) | (value[2] << 16) |
209 ((unsigned long)value[3] << 24);
210
211 rtc_time64_to_tm(secs, tm);
212
213 dev_dbg(dev, "secs = %lu, h:m:s == %ptRt, y-m-d = %ptRdr\n", secs, tm, tm);
214
215 return 0;
216}
217
218static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
219{
220 int rc, i;
221 u8 value[NUM_8_BIT_RTC_REGS];
222 unsigned int ctrl_reg;
223 unsigned long secs, irq_flags;
224 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
225 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
226
227 secs = rtc_tm_to_time64(&alarm->time);
228
229 for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) {
230 value[i] = secs & 0xFF;
231 secs >>= 8;
232 }
233
234 spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
235
236 rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
237 sizeof(value));
238 if (rc) {
239 dev_err(dev, "Write to RTC ALARM register failed\n");
240 goto rtc_rw_fail;
241 }
242
243 rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
244 if (rc)
245 goto rtc_rw_fail;
246
247 if (alarm->enabled)
248 ctrl_reg |= regs->alarm_en;
249 else
250 ctrl_reg &= ~regs->alarm_en;
251
252 rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
253 if (rc) {
254 dev_err(dev, "Write to RTC alarm control register failed\n");
255 goto rtc_rw_fail;
256 }
257
258 dev_dbg(dev, "Alarm Set for h:m:s=%ptRt, y-m-d=%ptRdr\n",
259 &alarm->time, &alarm->time);
260rtc_rw_fail:
261 spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
262 return rc;
263}
264
265static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
266{
267 int rc;
268 u8 value[NUM_8_BIT_RTC_REGS];
269 unsigned long secs;
270 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
271 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
272
273 rc = regmap_bulk_read(rtc_dd->regmap, regs->alarm_rw, value,
274 sizeof(value));
275 if (rc) {
276 dev_err(dev, "RTC alarm time read failed\n");
277 return rc;
278 }
279
280 secs = value[0] | (value[1] << 8) | (value[2] << 16) |
281 ((unsigned long)value[3] << 24);
282
283 rtc_time64_to_tm(secs, &alarm->time);
284
285 dev_dbg(dev, "Alarm set for - h:m:s=%ptRt, y-m-d=%ptRdr\n",
286 &alarm->time, &alarm->time);
287
288 return 0;
289}
290
291static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
292{
293 int rc;
294 unsigned long irq_flags;
295 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
296 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
297 unsigned int ctrl_reg;
298 u8 value[NUM_8_BIT_RTC_REGS] = {0};
299
300 spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
301
302 rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
303 if (rc)
304 goto rtc_rw_fail;
305
306 if (enable)
307 ctrl_reg |= regs->alarm_en;
308 else
309 ctrl_reg &= ~regs->alarm_en;
310
311 rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
312 if (rc) {
313 dev_err(dev, "Write to RTC control register failed\n");
314 goto rtc_rw_fail;
315 }
316
317 /* Clear Alarm register */
318 if (!enable) {
319 rc = regmap_bulk_write(rtc_dd->regmap, regs->alarm_rw, value,
320 sizeof(value));
321 if (rc) {
322 dev_err(dev, "Clear RTC ALARM register failed\n");
323 goto rtc_rw_fail;
324 }
325 }
326
327rtc_rw_fail:
328 spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
329 return rc;
330}
331
332static const struct rtc_class_ops pm8xxx_rtc_ops = {
333 .read_time = pm8xxx_rtc_read_time,
334 .set_time = pm8xxx_rtc_set_time,
335 .set_alarm = pm8xxx_rtc_set_alarm,
336 .read_alarm = pm8xxx_rtc_read_alarm,
337 .alarm_irq_enable = pm8xxx_rtc_alarm_irq_enable,
338};
339
340static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
341{
342 struct pm8xxx_rtc *rtc_dd = dev_id;
343 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
344 unsigned int ctrl_reg;
345 int rc;
346 unsigned long irq_flags;
347
348 rtc_update_irq(rtc_dd->rtc, 1, RTC_IRQF | RTC_AF);
349
350 spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
351
352 /* Clear the alarm enable bit */
353 rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg);
354 if (rc) {
355 spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
356 goto rtc_alarm_handled;
357 }
358
359 ctrl_reg &= ~regs->alarm_en;
360
361 rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg);
362 if (rc) {
363 spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
364 dev_err(rtc_dd->rtc_dev,
365 "Write to alarm control register failed\n");
366 goto rtc_alarm_handled;
367 }
368
369 spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
370
371 /* Clear RTC alarm register */
372 rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl2, &ctrl_reg);
373 if (rc) {
374 dev_err(rtc_dd->rtc_dev,
375 "RTC Alarm control2 register read failed\n");
376 goto rtc_alarm_handled;
377 }
378
379 ctrl_reg |= PM8xxx_RTC_ALARM_CLEAR;
380 rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl2, ctrl_reg);
381 if (rc)
382 dev_err(rtc_dd->rtc_dev,
383 "Write to RTC Alarm control2 register failed\n");
384
385rtc_alarm_handled:
386 return IRQ_HANDLED;
387}
388
389static int pm8xxx_rtc_enable(struct pm8xxx_rtc *rtc_dd)
390{
391 const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
392 unsigned int ctrl_reg;
393 int rc;
394
395 /* Check if the RTC is on, else turn it on */
396 rc = regmap_read(rtc_dd->regmap, regs->ctrl, &ctrl_reg);
397 if (rc)
398 return rc;
399
400 if (!(ctrl_reg & PM8xxx_RTC_ENABLE)) {
401 ctrl_reg |= PM8xxx_RTC_ENABLE;
402 rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg);
403 if (rc)
404 return rc;
405 }
406
407 return 0;
408}
409
410static const struct pm8xxx_rtc_regs pm8921_regs = {
411 .ctrl = 0x11d,
412 .write = 0x11f,
413 .read = 0x123,
414 .alarm_rw = 0x127,
415 .alarm_ctrl = 0x11d,
416 .alarm_ctrl2 = 0x11e,
417 .alarm_en = BIT(1),
418};
419
420static const struct pm8xxx_rtc_regs pm8058_regs = {
421 .ctrl = 0x1e8,
422 .write = 0x1ea,
423 .read = 0x1ee,
424 .alarm_rw = 0x1f2,
425 .alarm_ctrl = 0x1e8,
426 .alarm_ctrl2 = 0x1e9,
427 .alarm_en = BIT(1),
428};
429
430static const struct pm8xxx_rtc_regs pm8941_regs = {
431 .ctrl = 0x6046,
432 .write = 0x6040,
433 .read = 0x6048,
434 .alarm_rw = 0x6140,
435 .alarm_ctrl = 0x6146,
436 .alarm_ctrl2 = 0x6148,
437 .alarm_en = BIT(7),
438};
439
440/*
441 * Hardcoded RTC bases until IORESOURCE_REG mapping is figured out
442 */
443static const struct of_device_id pm8xxx_id_table[] = {
444 { .compatible = "qcom,pm8921-rtc", .data = &pm8921_regs },
445 { .compatible = "qcom,pm8018-rtc", .data = &pm8921_regs },
446 { .compatible = "qcom,pm8058-rtc", .data = &pm8058_regs },
447 { .compatible = "qcom,pm8941-rtc", .data = &pm8941_regs },
448 { },
449};
450MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
451
452static int pm8xxx_rtc_probe(struct platform_device *pdev)
453{
454 int rc;
455 struct pm8xxx_rtc *rtc_dd;
456 const struct of_device_id *match;
457
458 match = of_match_node(pm8xxx_id_table, pdev->dev.of_node);
459 if (!match)
460 return -ENXIO;
461
462 rtc_dd = devm_kzalloc(&pdev->dev, sizeof(*rtc_dd), GFP_KERNEL);
463 if (rtc_dd == NULL)
464 return -ENOMEM;
465
466 /* Initialise spinlock to protect RTC control register */
467 spin_lock_init(&rtc_dd->ctrl_reg_lock);
468
469 rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
470 if (!rtc_dd->regmap) {
471 dev_err(&pdev->dev, "Parent regmap unavailable.\n");
472 return -ENXIO;
473 }
474
475 rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
476 if (rtc_dd->rtc_alarm_irq < 0)
477 return -ENXIO;
478
479 rtc_dd->allow_set_time = of_property_read_bool(pdev->dev.of_node,
480 "allow-set-time");
481
482 rtc_dd->regs = match->data;
483 rtc_dd->rtc_dev = &pdev->dev;
484
485 rc = pm8xxx_rtc_enable(rtc_dd);
486 if (rc)
487 return rc;
488
489 platform_set_drvdata(pdev, rtc_dd);
490
491 device_init_wakeup(&pdev->dev, 1);
492
493 /* Register the RTC device */
494 rtc_dd->rtc = devm_rtc_allocate_device(&pdev->dev);
495 if (IS_ERR(rtc_dd->rtc))
496 return PTR_ERR(rtc_dd->rtc);
497
498 rtc_dd->rtc->ops = &pm8xxx_rtc_ops;
499 rtc_dd->rtc->range_max = U32_MAX;
500
501 /* Request the alarm IRQ */
502 rc = devm_request_any_context_irq(&pdev->dev, rtc_dd->rtc_alarm_irq,
503 pm8xxx_alarm_trigger,
504 IRQF_TRIGGER_RISING,
505 "pm8xxx_rtc_alarm", rtc_dd);
506 if (rc < 0) {
507 dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc);
508 return rc;
509 }
510
511 return rtc_register_device(rtc_dd->rtc);
512}
513
514#ifdef CONFIG_PM_SLEEP
515static int pm8xxx_rtc_resume(struct device *dev)
516{
517 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
518
519 if (device_may_wakeup(dev))
520 disable_irq_wake(rtc_dd->rtc_alarm_irq);
521
522 return 0;
523}
524
525static int pm8xxx_rtc_suspend(struct device *dev)
526{
527 struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
528
529 if (device_may_wakeup(dev))
530 enable_irq_wake(rtc_dd->rtc_alarm_irq);
531
532 return 0;
533}
534#endif
535
536static SIMPLE_DEV_PM_OPS(pm8xxx_rtc_pm_ops,
537 pm8xxx_rtc_suspend,
538 pm8xxx_rtc_resume);
539
540static struct platform_driver pm8xxx_rtc_driver = {
541 .probe = pm8xxx_rtc_probe,
542 .driver = {
543 .name = "rtc-pm8xxx",
544 .pm = &pm8xxx_rtc_pm_ops,
545 .of_match_table = pm8xxx_id_table,
546 },
547};
548
549module_platform_driver(pm8xxx_rtc_driver);
550
551MODULE_ALIAS("platform:rtc-pm8xxx");
552MODULE_DESCRIPTION("PMIC8xxx RTC driver");
553MODULE_LICENSE("GPL v2");
554MODULE_AUTHOR("Anirudh Ghayal <aghayal@codeaurora.org>");