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1// SPDX-License-Identifier: GPL-2.0+
2//
3// Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
4
5#include <linux/init.h>
6#include <linux/io.h>
7#include <linux/kernel.h>
8#include <linux/module.h>
9#include <linux/of.h>
10#include <linux/platform_device.h>
11#include <linux/pm_wakeirq.h>
12#include <linux/rtc.h>
13#include <linux/clk.h>
14#include <linux/mfd/syscon.h>
15#include <linux/regmap.h>
16
17#define SNVS_LPREGISTER_OFFSET 0x34
18
19/* These register offsets are relative to LP (Low Power) range */
20#define SNVS_LPCR 0x04
21#define SNVS_LPSR 0x18
22#define SNVS_LPSRTCMR 0x1c
23#define SNVS_LPSRTCLR 0x20
24#define SNVS_LPTAR 0x24
25#define SNVS_LPPGDR 0x30
26
27#define SNVS_LPCR_SRTC_ENV (1 << 0)
28#define SNVS_LPCR_LPTA_EN (1 << 1)
29#define SNVS_LPCR_LPWUI_EN (1 << 3)
30#define SNVS_LPSR_LPTA (1 << 0)
31
32#define SNVS_LPPGDR_INIT 0x41736166
33#define CNTR_TO_SECS_SH 15
34
35/* The maximum RTC clock cycles that are allowed to pass between two
36 * consecutive clock counter register reads. If the values are corrupted a
37 * bigger difference is expected. The RTC frequency is 32kHz. With 320 cycles
38 * we end at 10ms which should be enough for most cases. If it once takes
39 * longer than expected we do a retry.
40 */
41#define MAX_RTC_READ_DIFF_CYCLES 320
42
43struct snvs_rtc_data {
44 struct rtc_device *rtc;
45 struct regmap *regmap;
46 int offset;
47 int irq;
48 struct clk *clk;
49};
50
51/* Read 64 bit timer register, which could be in inconsistent state */
52static u64 rtc_read_lpsrt(struct snvs_rtc_data *data)
53{
54 u32 msb, lsb;
55
56 regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &msb);
57 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &lsb);
58 return (u64)msb << 32 | lsb;
59}
60
61/* Read the secure real time counter, taking care to deal with the cases of the
62 * counter updating while being read.
63 */
64static u32 rtc_read_lp_counter(struct snvs_rtc_data *data)
65{
66 u64 read1, read2;
67 s64 diff;
68 unsigned int timeout = 100;
69
70 /* As expected, the registers might update between the read of the LSB
71 * reg and the MSB reg. It's also possible that one register might be
72 * in partially modified state as well.
73 */
74 read1 = rtc_read_lpsrt(data);
75 do {
76 read2 = read1;
77 read1 = rtc_read_lpsrt(data);
78 diff = read1 - read2;
79 } while (((diff < 0) || (diff > MAX_RTC_READ_DIFF_CYCLES)) && --timeout);
80 if (!timeout)
81 dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n");
82
83 /* Convert 47-bit counter to 32-bit raw second count */
84 return (u32) (read1 >> CNTR_TO_SECS_SH);
85}
86
87/* Just read the lsb from the counter, dealing with inconsistent state */
88static int rtc_read_lp_counter_lsb(struct snvs_rtc_data *data, u32 *lsb)
89{
90 u32 count1, count2;
91 s32 diff;
92 unsigned int timeout = 100;
93
94 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
95 do {
96 count2 = count1;
97 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
98 diff = count1 - count2;
99 } while (((diff < 0) || (diff > MAX_RTC_READ_DIFF_CYCLES)) && --timeout);
100 if (!timeout) {
101 dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n");
102 return -ETIMEDOUT;
103 }
104
105 *lsb = count1;
106 return 0;
107}
108
109static int rtc_write_sync_lp(struct snvs_rtc_data *data)
110{
111 u32 count1, count2;
112 u32 elapsed;
113 unsigned int timeout = 1000;
114 int ret;
115
116 ret = rtc_read_lp_counter_lsb(data, &count1);
117 if (ret)
118 return ret;
119
120 /* Wait for 3 CKIL cycles, about 61.0-91.5 µs */
121 do {
122 ret = rtc_read_lp_counter_lsb(data, &count2);
123 if (ret)
124 return ret;
125 elapsed = count2 - count1; /* wrap around _is_ handled! */
126 } while (elapsed < 3 && --timeout);
127 if (!timeout) {
128 dev_err(&data->rtc->dev, "Timeout waiting for LPSRT Counter to change\n");
129 return -ETIMEDOUT;
130 }
131 return 0;
132}
133
134static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
135{
136 int timeout = 1000;
137 u32 lpcr;
138
139 regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV,
140 enable ? SNVS_LPCR_SRTC_ENV : 0);
141
142 while (--timeout) {
143 regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr);
144
145 if (enable) {
146 if (lpcr & SNVS_LPCR_SRTC_ENV)
147 break;
148 } else {
149 if (!(lpcr & SNVS_LPCR_SRTC_ENV))
150 break;
151 }
152 }
153
154 if (!timeout)
155 return -ETIMEDOUT;
156
157 return 0;
158}
159
160static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm)
161{
162 struct snvs_rtc_data *data = dev_get_drvdata(dev);
163 unsigned long time;
164 int ret;
165
166 ret = clk_enable(data->clk);
167 if (ret)
168 return ret;
169
170 time = rtc_read_lp_counter(data);
171 rtc_time64_to_tm(time, tm);
172
173 clk_disable(data->clk);
174
175 return 0;
176}
177
178static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
179{
180 struct snvs_rtc_data *data = dev_get_drvdata(dev);
181 unsigned long time = rtc_tm_to_time64(tm);
182 int ret;
183
184 ret = clk_enable(data->clk);
185 if (ret)
186 return ret;
187
188 /* Disable RTC first */
189 ret = snvs_rtc_enable(data, false);
190 if (ret)
191 return ret;
192
193 /* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */
194 regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH);
195 regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH));
196
197 /* Enable RTC again */
198 ret = snvs_rtc_enable(data, true);
199
200 clk_disable(data->clk);
201
202 return ret;
203}
204
205static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
206{
207 struct snvs_rtc_data *data = dev_get_drvdata(dev);
208 u32 lptar, lpsr;
209 int ret;
210
211 ret = clk_enable(data->clk);
212 if (ret)
213 return ret;
214
215 regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
216 rtc_time64_to_tm(lptar, &alrm->time);
217
218 regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
219 alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;
220
221 clk_disable(data->clk);
222
223 return 0;
224}
225
226static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
227{
228 struct snvs_rtc_data *data = dev_get_drvdata(dev);
229 int ret;
230
231 ret = clk_enable(data->clk);
232 if (ret)
233 return ret;
234
235 regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
236 (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN),
237 enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0);
238
239 ret = rtc_write_sync_lp(data);
240
241 clk_disable(data->clk);
242
243 return ret;
244}
245
246static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
247{
248 struct snvs_rtc_data *data = dev_get_drvdata(dev);
249 unsigned long time = rtc_tm_to_time64(&alrm->time);
250 int ret;
251
252 ret = clk_enable(data->clk);
253 if (ret)
254 return ret;
255
256 regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
257 ret = rtc_write_sync_lp(data);
258 if (ret)
259 return ret;
260 regmap_write(data->regmap, data->offset + SNVS_LPTAR, time);
261
262 /* Clear alarm interrupt status bit */
263 regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);
264
265 clk_disable(data->clk);
266
267 return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
268}
269
270static const struct rtc_class_ops snvs_rtc_ops = {
271 .read_time = snvs_rtc_read_time,
272 .set_time = snvs_rtc_set_time,
273 .read_alarm = snvs_rtc_read_alarm,
274 .set_alarm = snvs_rtc_set_alarm,
275 .alarm_irq_enable = snvs_rtc_alarm_irq_enable,
276};
277
278static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
279{
280 struct device *dev = dev_id;
281 struct snvs_rtc_data *data = dev_get_drvdata(dev);
282 u32 lpsr;
283 u32 events = 0;
284
285 clk_enable(data->clk);
286
287 regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
288
289 if (lpsr & SNVS_LPSR_LPTA) {
290 events |= (RTC_AF | RTC_IRQF);
291
292 /* RTC alarm should be one-shot */
293 snvs_rtc_alarm_irq_enable(dev, 0);
294
295 rtc_update_irq(data->rtc, 1, events);
296 }
297
298 /* clear interrupt status */
299 regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr);
300
301 clk_disable(data->clk);
302
303 return events ? IRQ_HANDLED : IRQ_NONE;
304}
305
306static const struct regmap_config snvs_rtc_config = {
307 .reg_bits = 32,
308 .val_bits = 32,
309 .reg_stride = 4,
310};
311
312static void snvs_rtc_action(void *data)
313{
314 clk_disable_unprepare(data);
315}
316
317static int snvs_rtc_probe(struct platform_device *pdev)
318{
319 struct snvs_rtc_data *data;
320 int ret;
321 void __iomem *mmio;
322
323 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
324 if (!data)
325 return -ENOMEM;
326
327 data->rtc = devm_rtc_allocate_device(&pdev->dev);
328 if (IS_ERR(data->rtc))
329 return PTR_ERR(data->rtc);
330
331 data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
332
333 if (IS_ERR(data->regmap)) {
334 dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n");
335
336 mmio = devm_platform_ioremap_resource(pdev, 0);
337 if (IS_ERR(mmio))
338 return PTR_ERR(mmio);
339
340 data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config);
341 } else {
342 data->offset = SNVS_LPREGISTER_OFFSET;
343 of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
344 }
345
346 if (IS_ERR(data->regmap)) {
347 dev_err(&pdev->dev, "Can't find snvs syscon\n");
348 return -ENODEV;
349 }
350
351 data->irq = platform_get_irq(pdev, 0);
352 if (data->irq < 0)
353 return data->irq;
354
355 data->clk = devm_clk_get(&pdev->dev, "snvs-rtc");
356 if (IS_ERR(data->clk)) {
357 data->clk = NULL;
358 } else {
359 ret = clk_prepare_enable(data->clk);
360 if (ret) {
361 dev_err(&pdev->dev,
362 "Could not prepare or enable the snvs clock\n");
363 return ret;
364 }
365 }
366
367 ret = devm_add_action_or_reset(&pdev->dev, snvs_rtc_action, data->clk);
368 if (ret)
369 return ret;
370
371 platform_set_drvdata(pdev, data);
372
373 /* Initialize glitch detect */
374 regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT);
375
376 /* Clear interrupt status */
377 regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff);
378
379 /* Enable RTC */
380 ret = snvs_rtc_enable(data, true);
381 if (ret) {
382 dev_err(&pdev->dev, "failed to enable rtc %d\n", ret);
383 return ret;
384 }
385
386 device_init_wakeup(&pdev->dev, true);
387 ret = dev_pm_set_wake_irq(&pdev->dev, data->irq);
388 if (ret)
389 dev_err(&pdev->dev, "failed to enable irq wake\n");
390
391 ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler,
392 IRQF_SHARED, "rtc alarm", &pdev->dev);
393 if (ret) {
394 dev_err(&pdev->dev, "failed to request irq %d: %d\n",
395 data->irq, ret);
396 return ret;
397 }
398
399 data->rtc->ops = &snvs_rtc_ops;
400 data->rtc->range_max = U32_MAX;
401
402 return devm_rtc_register_device(data->rtc);
403}
404
405static int __maybe_unused snvs_rtc_suspend_noirq(struct device *dev)
406{
407 struct snvs_rtc_data *data = dev_get_drvdata(dev);
408
409 clk_disable(data->clk);
410
411 return 0;
412}
413
414static int __maybe_unused snvs_rtc_resume_noirq(struct device *dev)
415{
416 struct snvs_rtc_data *data = dev_get_drvdata(dev);
417
418 if (data->clk)
419 return clk_enable(data->clk);
420
421 return 0;
422}
423
424static const struct dev_pm_ops snvs_rtc_pm_ops = {
425 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(snvs_rtc_suspend_noirq, snvs_rtc_resume_noirq)
426};
427
428static const struct of_device_id snvs_dt_ids[] = {
429 { .compatible = "fsl,sec-v4.0-mon-rtc-lp", },
430 { /* sentinel */ }
431};
432MODULE_DEVICE_TABLE(of, snvs_dt_ids);
433
434static struct platform_driver snvs_rtc_driver = {
435 .driver = {
436 .name = "snvs_rtc",
437 .pm = &snvs_rtc_pm_ops,
438 .of_match_table = snvs_dt_ids,
439 },
440 .probe = snvs_rtc_probe,
441};
442module_platform_driver(snvs_rtc_driver);
443
444MODULE_AUTHOR("Freescale Semiconductor, Inc.");
445MODULE_DESCRIPTION("Freescale SNVS RTC Driver");
446MODULE_LICENSE("GPL");
1/*
2 * Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
3 *
4 * The code contained herein is licensed under the GNU General Public
5 * License. You may obtain a copy of the GNU General Public License
6 * Version 2 or later at the following locations:
7 *
8 * http://www.opensource.org/licenses/gpl-license.html
9 * http://www.gnu.org/copyleft/gpl.html
10 */
11
12#include <linux/init.h>
13#include <linux/io.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_device.h>
18#include <linux/platform_device.h>
19#include <linux/rtc.h>
20#include <linux/clk.h>
21#include <linux/mfd/syscon.h>
22#include <linux/regmap.h>
23
24#define SNVS_LPREGISTER_OFFSET 0x34
25
26/* These register offsets are relative to LP (Low Power) range */
27#define SNVS_LPCR 0x04
28#define SNVS_LPSR 0x18
29#define SNVS_LPSRTCMR 0x1c
30#define SNVS_LPSRTCLR 0x20
31#define SNVS_LPTAR 0x24
32#define SNVS_LPPGDR 0x30
33
34#define SNVS_LPCR_SRTC_ENV (1 << 0)
35#define SNVS_LPCR_LPTA_EN (1 << 1)
36#define SNVS_LPCR_LPWUI_EN (1 << 3)
37#define SNVS_LPSR_LPTA (1 << 0)
38
39#define SNVS_LPPGDR_INIT 0x41736166
40#define CNTR_TO_SECS_SH 15
41
42struct snvs_rtc_data {
43 struct rtc_device *rtc;
44 struct regmap *regmap;
45 int offset;
46 int irq;
47 struct clk *clk;
48};
49
50static u32 rtc_read_lp_counter(struct snvs_rtc_data *data)
51{
52 u64 read1, read2;
53 u32 val;
54
55 do {
56 regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &val);
57 read1 = val;
58 read1 <<= 32;
59 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &val);
60 read1 |= val;
61
62 regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &val);
63 read2 = val;
64 read2 <<= 32;
65 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &val);
66 read2 |= val;
67 } while (read1 != read2);
68
69 /* Convert 47-bit counter to 32-bit raw second count */
70 return (u32) (read1 >> CNTR_TO_SECS_SH);
71}
72
73static void rtc_write_sync_lp(struct snvs_rtc_data *data)
74{
75 u32 count1, count2, count3;
76 int i;
77
78 /* Wait for 3 CKIL cycles */
79 for (i = 0; i < 3; i++) {
80 do {
81 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
82 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count2);
83 } while (count1 != count2);
84
85 /* Now wait until counter value changes */
86 do {
87 do {
88 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count2);
89 regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count3);
90 } while (count2 != count3);
91 } while (count3 == count1);
92 }
93}
94
95static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
96{
97 int timeout = 1000;
98 u32 lpcr;
99
100 regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV,
101 enable ? SNVS_LPCR_SRTC_ENV : 0);
102
103 while (--timeout) {
104 regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr);
105
106 if (enable) {
107 if (lpcr & SNVS_LPCR_SRTC_ENV)
108 break;
109 } else {
110 if (!(lpcr & SNVS_LPCR_SRTC_ENV))
111 break;
112 }
113 }
114
115 if (!timeout)
116 return -ETIMEDOUT;
117
118 return 0;
119}
120
121static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm)
122{
123 struct snvs_rtc_data *data = dev_get_drvdata(dev);
124 unsigned long time = rtc_read_lp_counter(data);
125
126 rtc_time_to_tm(time, tm);
127
128 return 0;
129}
130
131static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
132{
133 struct snvs_rtc_data *data = dev_get_drvdata(dev);
134 unsigned long time;
135 int ret;
136
137 rtc_tm_to_time(tm, &time);
138
139 /* Disable RTC first */
140 ret = snvs_rtc_enable(data, false);
141 if (ret)
142 return ret;
143
144 /* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */
145 regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH);
146 regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH));
147
148 /* Enable RTC again */
149 ret = snvs_rtc_enable(data, true);
150
151 return ret;
152}
153
154static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
155{
156 struct snvs_rtc_data *data = dev_get_drvdata(dev);
157 u32 lptar, lpsr;
158
159 regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
160 rtc_time_to_tm(lptar, &alrm->time);
161
162 regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
163 alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;
164
165 return 0;
166}
167
168static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
169{
170 struct snvs_rtc_data *data = dev_get_drvdata(dev);
171
172 regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
173 (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN),
174 enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0);
175
176 rtc_write_sync_lp(data);
177
178 return 0;
179}
180
181static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
182{
183 struct snvs_rtc_data *data = dev_get_drvdata(dev);
184 struct rtc_time *alrm_tm = &alrm->time;
185 unsigned long time;
186
187 rtc_tm_to_time(alrm_tm, &time);
188
189 regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
190 rtc_write_sync_lp(data);
191 regmap_write(data->regmap, data->offset + SNVS_LPTAR, time);
192
193 /* Clear alarm interrupt status bit */
194 regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);
195
196 return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
197}
198
199static const struct rtc_class_ops snvs_rtc_ops = {
200 .read_time = snvs_rtc_read_time,
201 .set_time = snvs_rtc_set_time,
202 .read_alarm = snvs_rtc_read_alarm,
203 .set_alarm = snvs_rtc_set_alarm,
204 .alarm_irq_enable = snvs_rtc_alarm_irq_enable,
205};
206
207static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
208{
209 struct device *dev = dev_id;
210 struct snvs_rtc_data *data = dev_get_drvdata(dev);
211 u32 lpsr;
212 u32 events = 0;
213
214 regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
215
216 if (lpsr & SNVS_LPSR_LPTA) {
217 events |= (RTC_AF | RTC_IRQF);
218
219 /* RTC alarm should be one-shot */
220 snvs_rtc_alarm_irq_enable(dev, 0);
221
222 rtc_update_irq(data->rtc, 1, events);
223 }
224
225 /* clear interrupt status */
226 regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr);
227
228 return events ? IRQ_HANDLED : IRQ_NONE;
229}
230
231static const struct regmap_config snvs_rtc_config = {
232 .reg_bits = 32,
233 .val_bits = 32,
234 .reg_stride = 4,
235};
236
237static int snvs_rtc_probe(struct platform_device *pdev)
238{
239 struct snvs_rtc_data *data;
240 struct resource *res;
241 int ret;
242 void __iomem *mmio;
243
244 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
245 if (!data)
246 return -ENOMEM;
247
248 data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
249
250 if (IS_ERR(data->regmap)) {
251 dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n");
252 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
253
254 mmio = devm_ioremap_resource(&pdev->dev, res);
255 if (IS_ERR(mmio))
256 return PTR_ERR(mmio);
257
258 data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config);
259 } else {
260 data->offset = SNVS_LPREGISTER_OFFSET;
261 of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
262 }
263
264 if (IS_ERR(data->regmap)) {
265 dev_err(&pdev->dev, "Can't find snvs syscon\n");
266 return -ENODEV;
267 }
268
269 data->irq = platform_get_irq(pdev, 0);
270 if (data->irq < 0)
271 return data->irq;
272
273 data->clk = devm_clk_get(&pdev->dev, "snvs-rtc");
274 if (IS_ERR(data->clk)) {
275 data->clk = NULL;
276 } else {
277 ret = clk_prepare_enable(data->clk);
278 if (ret) {
279 dev_err(&pdev->dev,
280 "Could not prepare or enable the snvs clock\n");
281 return ret;
282 }
283 }
284
285 platform_set_drvdata(pdev, data);
286
287 /* Initialize glitch detect */
288 regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT);
289
290 /* Clear interrupt status */
291 regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff);
292
293 /* Enable RTC */
294 ret = snvs_rtc_enable(data, true);
295 if (ret) {
296 dev_err(&pdev->dev, "failed to enable rtc %d\n", ret);
297 goto error_rtc_device_register;
298 }
299
300 device_init_wakeup(&pdev->dev, true);
301
302 ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler,
303 IRQF_SHARED, "rtc alarm", &pdev->dev);
304 if (ret) {
305 dev_err(&pdev->dev, "failed to request irq %d: %d\n",
306 data->irq, ret);
307 goto error_rtc_device_register;
308 }
309
310 data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
311 &snvs_rtc_ops, THIS_MODULE);
312 if (IS_ERR(data->rtc)) {
313 ret = PTR_ERR(data->rtc);
314 dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
315 goto error_rtc_device_register;
316 }
317
318 return 0;
319
320error_rtc_device_register:
321 if (data->clk)
322 clk_disable_unprepare(data->clk);
323
324 return ret;
325}
326
327#ifdef CONFIG_PM_SLEEP
328static int snvs_rtc_suspend(struct device *dev)
329{
330 struct snvs_rtc_data *data = dev_get_drvdata(dev);
331
332 if (device_may_wakeup(dev))
333 return enable_irq_wake(data->irq);
334
335 return 0;
336}
337
338static int snvs_rtc_suspend_noirq(struct device *dev)
339{
340 struct snvs_rtc_data *data = dev_get_drvdata(dev);
341
342 if (data->clk)
343 clk_disable_unprepare(data->clk);
344
345 return 0;
346}
347
348static int snvs_rtc_resume(struct device *dev)
349{
350 struct snvs_rtc_data *data = dev_get_drvdata(dev);
351
352 if (device_may_wakeup(dev))
353 return disable_irq_wake(data->irq);
354
355 return 0;
356}
357
358static int snvs_rtc_resume_noirq(struct device *dev)
359{
360 struct snvs_rtc_data *data = dev_get_drvdata(dev);
361
362 if (data->clk)
363 return clk_prepare_enable(data->clk);
364
365 return 0;
366}
367
368static const struct dev_pm_ops snvs_rtc_pm_ops = {
369 .suspend = snvs_rtc_suspend,
370 .suspend_noirq = snvs_rtc_suspend_noirq,
371 .resume = snvs_rtc_resume,
372 .resume_noirq = snvs_rtc_resume_noirq,
373};
374
375#define SNVS_RTC_PM_OPS (&snvs_rtc_pm_ops)
376
377#else
378
379#define SNVS_RTC_PM_OPS NULL
380
381#endif
382
383static const struct of_device_id snvs_dt_ids[] = {
384 { .compatible = "fsl,sec-v4.0-mon-rtc-lp", },
385 { /* sentinel */ }
386};
387MODULE_DEVICE_TABLE(of, snvs_dt_ids);
388
389static struct platform_driver snvs_rtc_driver = {
390 .driver = {
391 .name = "snvs_rtc",
392 .pm = SNVS_RTC_PM_OPS,
393 .of_match_table = snvs_dt_ids,
394 },
395 .probe = snvs_rtc_probe,
396};
397module_platform_driver(snvs_rtc_driver);
398
399MODULE_AUTHOR("Freescale Semiconductor, Inc.");
400MODULE_DESCRIPTION("Freescale SNVS RTC Driver");
401MODULE_LICENSE("GPL");