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1/*
2 * Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
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/io.h>
13#include <linux/rtc.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/interrupt.h>
17#include <linux/platform_device.h>
18#include <linux/clk.h>
19
20#include <mach/hardware.h>
21
22#define RTC_INPUT_CLK_32768HZ (0x00 << 5)
23#define RTC_INPUT_CLK_32000HZ (0x01 << 5)
24#define RTC_INPUT_CLK_38400HZ (0x02 << 5)
25
26#define RTC_SW_BIT (1 << 0)
27#define RTC_ALM_BIT (1 << 2)
28#define RTC_1HZ_BIT (1 << 4)
29#define RTC_2HZ_BIT (1 << 7)
30#define RTC_SAM0_BIT (1 << 8)
31#define RTC_SAM1_BIT (1 << 9)
32#define RTC_SAM2_BIT (1 << 10)
33#define RTC_SAM3_BIT (1 << 11)
34#define RTC_SAM4_BIT (1 << 12)
35#define RTC_SAM5_BIT (1 << 13)
36#define RTC_SAM6_BIT (1 << 14)
37#define RTC_SAM7_BIT (1 << 15)
38#define PIT_ALL_ON (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
39 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
40 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
41
42#define RTC_ENABLE_BIT (1 << 7)
43
44#define MAX_PIE_NUM 9
45#define MAX_PIE_FREQ 512
46static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
47 { 2, RTC_2HZ_BIT },
48 { 4, RTC_SAM0_BIT },
49 { 8, RTC_SAM1_BIT },
50 { 16, RTC_SAM2_BIT },
51 { 32, RTC_SAM3_BIT },
52 { 64, RTC_SAM4_BIT },
53 { 128, RTC_SAM5_BIT },
54 { 256, RTC_SAM6_BIT },
55 { MAX_PIE_FREQ, RTC_SAM7_BIT },
56};
57
58#define MXC_RTC_TIME 0
59#define MXC_RTC_ALARM 1
60
61#define RTC_HOURMIN 0x00 /* 32bit rtc hour/min counter reg */
62#define RTC_SECOND 0x04 /* 32bit rtc seconds counter reg */
63#define RTC_ALRM_HM 0x08 /* 32bit rtc alarm hour/min reg */
64#define RTC_ALRM_SEC 0x0C /* 32bit rtc alarm seconds reg */
65#define RTC_RTCCTL 0x10 /* 32bit rtc control reg */
66#define RTC_RTCISR 0x14 /* 32bit rtc interrupt status reg */
67#define RTC_RTCIENR 0x18 /* 32bit rtc interrupt enable reg */
68#define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */
69#define RTC_DAYR 0x20 /* 32bit rtc days counter reg */
70#define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */
71#define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */
72#define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */
73#define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */
74
75struct rtc_plat_data {
76 struct rtc_device *rtc;
77 void __iomem *ioaddr;
78 int irq;
79 struct clk *clk;
80 struct rtc_time g_rtc_alarm;
81};
82
83/*
84 * This function is used to obtain the RTC time or the alarm value in
85 * second.
86 */
87static u32 get_alarm_or_time(struct device *dev, int time_alarm)
88{
89 struct platform_device *pdev = to_platform_device(dev);
90 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
91 void __iomem *ioaddr = pdata->ioaddr;
92 u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
93
94 switch (time_alarm) {
95 case MXC_RTC_TIME:
96 day = readw(ioaddr + RTC_DAYR);
97 hr_min = readw(ioaddr + RTC_HOURMIN);
98 sec = readw(ioaddr + RTC_SECOND);
99 break;
100 case MXC_RTC_ALARM:
101 day = readw(ioaddr + RTC_DAYALARM);
102 hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
103 sec = readw(ioaddr + RTC_ALRM_SEC);
104 break;
105 }
106
107 hr = hr_min >> 8;
108 min = hr_min & 0xff;
109
110 return (((day * 24 + hr) * 60) + min) * 60 + sec;
111}
112
113/*
114 * This function sets the RTC alarm value or the time value.
115 */
116static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
117{
118 u32 day, hr, min, sec, temp;
119 struct platform_device *pdev = to_platform_device(dev);
120 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
121 void __iomem *ioaddr = pdata->ioaddr;
122
123 day = time / 86400;
124 time -= day * 86400;
125
126 /* time is within a day now */
127 hr = time / 3600;
128 time -= hr * 3600;
129
130 /* time is within an hour now */
131 min = time / 60;
132 sec = time - min * 60;
133
134 temp = (hr << 8) + min;
135
136 switch (time_alarm) {
137 case MXC_RTC_TIME:
138 writew(day, ioaddr + RTC_DAYR);
139 writew(sec, ioaddr + RTC_SECOND);
140 writew(temp, ioaddr + RTC_HOURMIN);
141 break;
142 case MXC_RTC_ALARM:
143 writew(day, ioaddr + RTC_DAYALARM);
144 writew(sec, ioaddr + RTC_ALRM_SEC);
145 writew(temp, ioaddr + RTC_ALRM_HM);
146 break;
147 }
148}
149
150/*
151 * This function updates the RTC alarm registers and then clears all the
152 * interrupt status bits.
153 */
154static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
155{
156 struct rtc_time alarm_tm, now_tm;
157 unsigned long now, time;
158 int ret;
159 struct platform_device *pdev = to_platform_device(dev);
160 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
161 void __iomem *ioaddr = pdata->ioaddr;
162
163 now = get_alarm_or_time(dev, MXC_RTC_TIME);
164 rtc_time_to_tm(now, &now_tm);
165 alarm_tm.tm_year = now_tm.tm_year;
166 alarm_tm.tm_mon = now_tm.tm_mon;
167 alarm_tm.tm_mday = now_tm.tm_mday;
168 alarm_tm.tm_hour = alrm->tm_hour;
169 alarm_tm.tm_min = alrm->tm_min;
170 alarm_tm.tm_sec = alrm->tm_sec;
171 rtc_tm_to_time(&now_tm, &now);
172 rtc_tm_to_time(&alarm_tm, &time);
173
174 if (time < now) {
175 time += 60 * 60 * 24;
176 rtc_time_to_tm(time, &alarm_tm);
177 }
178
179 ret = rtc_tm_to_time(&alarm_tm, &time);
180
181 /* clear all the interrupt status bits */
182 writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
183 set_alarm_or_time(dev, MXC_RTC_ALARM, time);
184
185 return ret;
186}
187
188/* This function is the RTC interrupt service routine. */
189static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
190{
191 struct platform_device *pdev = dev_id;
192 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
193 void __iomem *ioaddr = pdata->ioaddr;
194 u32 status;
195 u32 events = 0;
196
197 spin_lock_irq(&pdata->rtc->irq_lock);
198 status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
199 /* clear interrupt sources */
200 writew(status, ioaddr + RTC_RTCISR);
201
202 /* clear alarm interrupt if it has occurred */
203 if (status & RTC_ALM_BIT)
204 status &= ~RTC_ALM_BIT;
205
206 /* update irq data & counter */
207 if (status & RTC_ALM_BIT)
208 events |= (RTC_AF | RTC_IRQF);
209
210 if (status & RTC_1HZ_BIT)
211 events |= (RTC_UF | RTC_IRQF);
212
213 if (status & PIT_ALL_ON)
214 events |= (RTC_PF | RTC_IRQF);
215
216 if ((status & RTC_ALM_BIT) && rtc_valid_tm(&pdata->g_rtc_alarm))
217 rtc_update_alarm(&pdev->dev, &pdata->g_rtc_alarm);
218
219 rtc_update_irq(pdata->rtc, 1, events);
220 spin_unlock_irq(&pdata->rtc->irq_lock);
221
222 return IRQ_HANDLED;
223}
224
225/*
226 * Clear all interrupts and release the IRQ
227 */
228static void mxc_rtc_release(struct device *dev)
229{
230 struct platform_device *pdev = to_platform_device(dev);
231 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
232 void __iomem *ioaddr = pdata->ioaddr;
233
234 spin_lock_irq(&pdata->rtc->irq_lock);
235
236 /* Disable all rtc interrupts */
237 writew(0, ioaddr + RTC_RTCIENR);
238
239 /* Clear all interrupt status */
240 writew(0xffffffff, ioaddr + RTC_RTCISR);
241
242 spin_unlock_irq(&pdata->rtc->irq_lock);
243}
244
245static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
246 unsigned int enabled)
247{
248 struct platform_device *pdev = to_platform_device(dev);
249 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
250 void __iomem *ioaddr = pdata->ioaddr;
251 u32 reg;
252
253 spin_lock_irq(&pdata->rtc->irq_lock);
254 reg = readw(ioaddr + RTC_RTCIENR);
255
256 if (enabled)
257 reg |= bit;
258 else
259 reg &= ~bit;
260
261 writew(reg, ioaddr + RTC_RTCIENR);
262 spin_unlock_irq(&pdata->rtc->irq_lock);
263}
264
265static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
266{
267 mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
268 return 0;
269}
270
271/*
272 * This function reads the current RTC time into tm in Gregorian date.
273 */
274static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
275{
276 u32 val;
277
278 /* Avoid roll-over from reading the different registers */
279 do {
280 val = get_alarm_or_time(dev, MXC_RTC_TIME);
281 } while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
282
283 rtc_time_to_tm(val, tm);
284
285 return 0;
286}
287
288/*
289 * This function sets the internal RTC time based on tm in Gregorian date.
290 */
291static int mxc_rtc_set_mmss(struct device *dev, unsigned long time)
292{
293 /* Avoid roll-over from reading the different registers */
294 do {
295 set_alarm_or_time(dev, MXC_RTC_TIME, time);
296 } while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
297
298 return 0;
299}
300
301/*
302 * This function reads the current alarm value into the passed in 'alrm'
303 * argument. It updates the alrm's pending field value based on the whether
304 * an alarm interrupt occurs or not.
305 */
306static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
307{
308 struct platform_device *pdev = to_platform_device(dev);
309 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
310 void __iomem *ioaddr = pdata->ioaddr;
311
312 rtc_time_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
313 alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
314
315 return 0;
316}
317
318/*
319 * This function sets the RTC alarm based on passed in alrm.
320 */
321static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
322{
323 struct platform_device *pdev = to_platform_device(dev);
324 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
325 int ret;
326
327 if (rtc_valid_tm(&alrm->time)) {
328 if (alrm->time.tm_sec > 59 ||
329 alrm->time.tm_hour > 23 ||
330 alrm->time.tm_min > 59)
331 return -EINVAL;
332
333 ret = rtc_update_alarm(dev, &alrm->time);
334 } else {
335 ret = rtc_valid_tm(&alrm->time);
336 if (ret)
337 return ret;
338
339 ret = rtc_update_alarm(dev, &alrm->time);
340 }
341
342 if (ret)
343 return ret;
344
345 memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
346 mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
347
348 return 0;
349}
350
351/* RTC layer */
352static struct rtc_class_ops mxc_rtc_ops = {
353 .release = mxc_rtc_release,
354 .read_time = mxc_rtc_read_time,
355 .set_mmss = mxc_rtc_set_mmss,
356 .read_alarm = mxc_rtc_read_alarm,
357 .set_alarm = mxc_rtc_set_alarm,
358 .alarm_irq_enable = mxc_rtc_alarm_irq_enable,
359};
360
361static int __init mxc_rtc_probe(struct platform_device *pdev)
362{
363 struct resource *res;
364 struct rtc_device *rtc;
365 struct rtc_plat_data *pdata = NULL;
366 u32 reg;
367 unsigned long rate;
368 int ret;
369
370 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
371 if (!res)
372 return -ENODEV;
373
374 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
375 if (!pdata)
376 return -ENOMEM;
377
378 if (!devm_request_mem_region(&pdev->dev, res->start,
379 resource_size(res), pdev->name))
380 return -EBUSY;
381
382 pdata->ioaddr = devm_ioremap(&pdev->dev, res->start,
383 resource_size(res));
384
385 pdata->clk = clk_get(&pdev->dev, "rtc");
386 if (IS_ERR(pdata->clk)) {
387 dev_err(&pdev->dev, "unable to get clock!\n");
388 ret = PTR_ERR(pdata->clk);
389 goto exit_free_pdata;
390 }
391
392 clk_enable(pdata->clk);
393 rate = clk_get_rate(pdata->clk);
394
395 if (rate == 32768)
396 reg = RTC_INPUT_CLK_32768HZ;
397 else if (rate == 32000)
398 reg = RTC_INPUT_CLK_32000HZ;
399 else if (rate == 38400)
400 reg = RTC_INPUT_CLK_38400HZ;
401 else {
402 dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
403 ret = -EINVAL;
404 goto exit_put_clk;
405 }
406
407 reg |= RTC_ENABLE_BIT;
408 writew(reg, (pdata->ioaddr + RTC_RTCCTL));
409 if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
410 dev_err(&pdev->dev, "hardware module can't be enabled!\n");
411 ret = -EIO;
412 goto exit_put_clk;
413 }
414
415 platform_set_drvdata(pdev, pdata);
416
417 /* Configure and enable the RTC */
418 pdata->irq = platform_get_irq(pdev, 0);
419
420 if (pdata->irq >= 0 &&
421 devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
422 IRQF_SHARED, pdev->name, pdev) < 0) {
423 dev_warn(&pdev->dev, "interrupt not available.\n");
424 pdata->irq = -1;
425 }
426
427 rtc = rtc_device_register(pdev->name, &pdev->dev, &mxc_rtc_ops,
428 THIS_MODULE);
429 if (IS_ERR(rtc)) {
430 ret = PTR_ERR(rtc);
431 goto exit_clr_drvdata;
432 }
433
434 pdata->rtc = rtc;
435
436 return 0;
437
438exit_clr_drvdata:
439 platform_set_drvdata(pdev, NULL);
440exit_put_clk:
441 clk_disable(pdata->clk);
442 clk_put(pdata->clk);
443
444exit_free_pdata:
445
446 return ret;
447}
448
449static int __exit mxc_rtc_remove(struct platform_device *pdev)
450{
451 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
452
453 rtc_device_unregister(pdata->rtc);
454
455 clk_disable(pdata->clk);
456 clk_put(pdata->clk);
457 platform_set_drvdata(pdev, NULL);
458
459 return 0;
460}
461
462static struct platform_driver mxc_rtc_driver = {
463 .driver = {
464 .name = "mxc_rtc",
465 .owner = THIS_MODULE,
466 },
467 .remove = __exit_p(mxc_rtc_remove),
468};
469
470static int __init mxc_rtc_init(void)
471{
472 return platform_driver_probe(&mxc_rtc_driver, mxc_rtc_probe);
473}
474
475static void __exit mxc_rtc_exit(void)
476{
477 platform_driver_unregister(&mxc_rtc_driver);
478}
479
480module_init(mxc_rtc_init);
481module_exit(mxc_rtc_exit);
482
483MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
484MODULE_DESCRIPTION("RTC driver for Freescale MXC");
485MODULE_LICENSE("GPL");
486
1// SPDX-License-Identifier: GPL-2.0+
2//
3// Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
4
5#include <linux/io.h>
6#include <linux/rtc.h>
7#include <linux/module.h>
8#include <linux/slab.h>
9#include <linux/interrupt.h>
10#include <linux/platform_device.h>
11#include <linux/pm_wakeirq.h>
12#include <linux/clk.h>
13#include <linux/of.h>
14#include <linux/of_device.h>
15
16#define RTC_INPUT_CLK_32768HZ (0x00 << 5)
17#define RTC_INPUT_CLK_32000HZ (0x01 << 5)
18#define RTC_INPUT_CLK_38400HZ (0x02 << 5)
19
20#define RTC_SW_BIT (1 << 0)
21#define RTC_ALM_BIT (1 << 2)
22#define RTC_1HZ_BIT (1 << 4)
23#define RTC_2HZ_BIT (1 << 7)
24#define RTC_SAM0_BIT (1 << 8)
25#define RTC_SAM1_BIT (1 << 9)
26#define RTC_SAM2_BIT (1 << 10)
27#define RTC_SAM3_BIT (1 << 11)
28#define RTC_SAM4_BIT (1 << 12)
29#define RTC_SAM5_BIT (1 << 13)
30#define RTC_SAM6_BIT (1 << 14)
31#define RTC_SAM7_BIT (1 << 15)
32#define PIT_ALL_ON (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
33 RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
34 RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
35
36#define RTC_ENABLE_BIT (1 << 7)
37
38#define MAX_PIE_NUM 9
39#define MAX_PIE_FREQ 512
40
41#define MXC_RTC_TIME 0
42#define MXC_RTC_ALARM 1
43
44#define RTC_HOURMIN 0x00 /* 32bit rtc hour/min counter reg */
45#define RTC_SECOND 0x04 /* 32bit rtc seconds counter reg */
46#define RTC_ALRM_HM 0x08 /* 32bit rtc alarm hour/min reg */
47#define RTC_ALRM_SEC 0x0C /* 32bit rtc alarm seconds reg */
48#define RTC_RTCCTL 0x10 /* 32bit rtc control reg */
49#define RTC_RTCISR 0x14 /* 32bit rtc interrupt status reg */
50#define RTC_RTCIENR 0x18 /* 32bit rtc interrupt enable reg */
51#define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */
52#define RTC_DAYR 0x20 /* 32bit rtc days counter reg */
53#define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */
54#define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */
55#define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */
56#define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */
57
58enum imx_rtc_type {
59 IMX1_RTC,
60 IMX21_RTC,
61};
62
63struct rtc_plat_data {
64 struct rtc_device *rtc;
65 void __iomem *ioaddr;
66 int irq;
67 struct clk *clk_ref;
68 struct clk *clk_ipg;
69 struct rtc_time g_rtc_alarm;
70 enum imx_rtc_type devtype;
71};
72
73static const struct of_device_id imx_rtc_dt_ids[] = {
74 { .compatible = "fsl,imx1-rtc", .data = (const void *)IMX1_RTC },
75 { .compatible = "fsl,imx21-rtc", .data = (const void *)IMX21_RTC },
76 {}
77};
78MODULE_DEVICE_TABLE(of, imx_rtc_dt_ids);
79
80static inline int is_imx1_rtc(struct rtc_plat_data *data)
81{
82 return data->devtype == IMX1_RTC;
83}
84
85/*
86 * This function is used to obtain the RTC time or the alarm value in
87 * second.
88 */
89static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
90{
91 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
92 void __iomem *ioaddr = pdata->ioaddr;
93 u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
94
95 switch (time_alarm) {
96 case MXC_RTC_TIME:
97 day = readw(ioaddr + RTC_DAYR);
98 hr_min = readw(ioaddr + RTC_HOURMIN);
99 sec = readw(ioaddr + RTC_SECOND);
100 break;
101 case MXC_RTC_ALARM:
102 day = readw(ioaddr + RTC_DAYALARM);
103 hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
104 sec = readw(ioaddr + RTC_ALRM_SEC);
105 break;
106 }
107
108 hr = hr_min >> 8;
109 min = hr_min & 0xff;
110
111 return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
112}
113
114/*
115 * This function sets the RTC alarm value or the time value.
116 */
117static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
118{
119 u32 tod, day, hr, min, sec, temp;
120 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
121 void __iomem *ioaddr = pdata->ioaddr;
122
123 day = div_s64_rem(time, 86400, &tod);
124
125 /* time is within a day now */
126 hr = tod / 3600;
127 tod -= hr * 3600;
128
129 /* time is within an hour now */
130 min = tod / 60;
131 sec = tod - min * 60;
132
133 temp = (hr << 8) + min;
134
135 switch (time_alarm) {
136 case MXC_RTC_TIME:
137 writew(day, ioaddr + RTC_DAYR);
138 writew(sec, ioaddr + RTC_SECOND);
139 writew(temp, ioaddr + RTC_HOURMIN);
140 break;
141 case MXC_RTC_ALARM:
142 writew(day, ioaddr + RTC_DAYALARM);
143 writew(sec, ioaddr + RTC_ALRM_SEC);
144 writew(temp, ioaddr + RTC_ALRM_HM);
145 break;
146 }
147}
148
149/*
150 * This function updates the RTC alarm registers and then clears all the
151 * interrupt status bits.
152 */
153static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
154{
155 time64_t time;
156 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
157 void __iomem *ioaddr = pdata->ioaddr;
158
159 time = rtc_tm_to_time64(alrm);
160
161 /* clear all the interrupt status bits */
162 writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
163 set_alarm_or_time(dev, MXC_RTC_ALARM, time);
164}
165
166static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
167 unsigned int enabled)
168{
169 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
170 void __iomem *ioaddr = pdata->ioaddr;
171 u32 reg;
172 unsigned long flags;
173
174 spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
175 reg = readw(ioaddr + RTC_RTCIENR);
176
177 if (enabled)
178 reg |= bit;
179 else
180 reg &= ~bit;
181
182 writew(reg, ioaddr + RTC_RTCIENR);
183 spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
184}
185
186/* This function is the RTC interrupt service routine. */
187static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
188{
189 struct platform_device *pdev = dev_id;
190 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
191 void __iomem *ioaddr = pdata->ioaddr;
192 u32 status;
193 u32 events = 0;
194
195 spin_lock(&pdata->rtc->irq_lock);
196 status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
197 /* clear interrupt sources */
198 writew(status, ioaddr + RTC_RTCISR);
199
200 /* update irq data & counter */
201 if (status & RTC_ALM_BIT) {
202 events |= (RTC_AF | RTC_IRQF);
203 /* RTC alarm should be one-shot */
204 mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
205 }
206
207 if (status & PIT_ALL_ON)
208 events |= (RTC_PF | RTC_IRQF);
209
210 rtc_update_irq(pdata->rtc, 1, events);
211 spin_unlock(&pdata->rtc->irq_lock);
212
213 return IRQ_HANDLED;
214}
215
216static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
217{
218 mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
219 return 0;
220}
221
222/*
223 * This function reads the current RTC time into tm in Gregorian date.
224 */
225static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
226{
227 time64_t val;
228
229 /* Avoid roll-over from reading the different registers */
230 do {
231 val = get_alarm_or_time(dev, MXC_RTC_TIME);
232 } while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
233
234 rtc_time64_to_tm(val, tm);
235
236 return 0;
237}
238
239/*
240 * This function sets the internal RTC time based on tm in Gregorian date.
241 */
242static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm)
243{
244 time64_t time = rtc_tm_to_time64(tm);
245
246 /* Avoid roll-over from reading the different registers */
247 do {
248 set_alarm_or_time(dev, MXC_RTC_TIME, time);
249 } while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
250
251 return 0;
252}
253
254/*
255 * This function reads the current alarm value into the passed in 'alrm'
256 * argument. It updates the alrm's pending field value based on the whether
257 * an alarm interrupt occurs or not.
258 */
259static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
260{
261 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
262 void __iomem *ioaddr = pdata->ioaddr;
263
264 rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
265 alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
266
267 return 0;
268}
269
270/*
271 * This function sets the RTC alarm based on passed in alrm.
272 */
273static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
274{
275 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
276
277 rtc_update_alarm(dev, &alrm->time);
278
279 memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
280 mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
281
282 return 0;
283}
284
285/* RTC layer */
286static const struct rtc_class_ops mxc_rtc_ops = {
287 .read_time = mxc_rtc_read_time,
288 .set_time = mxc_rtc_set_time,
289 .read_alarm = mxc_rtc_read_alarm,
290 .set_alarm = mxc_rtc_set_alarm,
291 .alarm_irq_enable = mxc_rtc_alarm_irq_enable,
292};
293
294static int mxc_rtc_probe(struct platform_device *pdev)
295{
296 struct rtc_device *rtc;
297 struct rtc_plat_data *pdata = NULL;
298 u32 reg;
299 unsigned long rate;
300 int ret;
301
302 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
303 if (!pdata)
304 return -ENOMEM;
305
306 pdata->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);
307
308 pdata->ioaddr = devm_platform_ioremap_resource(pdev, 0);
309 if (IS_ERR(pdata->ioaddr))
310 return PTR_ERR(pdata->ioaddr);
311
312 rtc = devm_rtc_allocate_device(&pdev->dev);
313 if (IS_ERR(rtc))
314 return PTR_ERR(rtc);
315
316 pdata->rtc = rtc;
317 rtc->ops = &mxc_rtc_ops;
318 if (is_imx1_rtc(pdata)) {
319 struct rtc_time tm;
320
321 /* 9bit days + hours minutes seconds */
322 rtc->range_max = (1 << 9) * 86400 - 1;
323
324 /*
325 * Set the start date as beginning of the current year. This can
326 * be overridden using device tree.
327 */
328 rtc_time64_to_tm(ktime_get_real_seconds(), &tm);
329 rtc->start_secs = mktime64(tm.tm_year, 1, 1, 0, 0, 0);
330 rtc->set_start_time = true;
331 } else {
332 /* 16bit days + hours minutes seconds */
333 rtc->range_max = (1 << 16) * 86400ULL - 1;
334 }
335
336 pdata->clk_ipg = devm_clk_get_enabled(&pdev->dev, "ipg");
337 if (IS_ERR(pdata->clk_ipg)) {
338 dev_err(&pdev->dev, "unable to get ipg clock!\n");
339 return PTR_ERR(pdata->clk_ipg);
340 }
341
342 pdata->clk_ref = devm_clk_get_enabled(&pdev->dev, "ref");
343 if (IS_ERR(pdata->clk_ref)) {
344 dev_err(&pdev->dev, "unable to get ref clock!\n");
345 return PTR_ERR(pdata->clk_ref);
346 }
347
348 rate = clk_get_rate(pdata->clk_ref);
349
350 if (rate == 32768)
351 reg = RTC_INPUT_CLK_32768HZ;
352 else if (rate == 32000)
353 reg = RTC_INPUT_CLK_32000HZ;
354 else if (rate == 38400)
355 reg = RTC_INPUT_CLK_38400HZ;
356 else {
357 dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
358 return -EINVAL;
359 }
360
361 reg |= RTC_ENABLE_BIT;
362 writew(reg, (pdata->ioaddr + RTC_RTCCTL));
363 if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
364 dev_err(&pdev->dev, "hardware module can't be enabled!\n");
365 return -EIO;
366 }
367
368 platform_set_drvdata(pdev, pdata);
369
370 /* Configure and enable the RTC */
371 pdata->irq = platform_get_irq(pdev, 0);
372
373 if (pdata->irq >= 0 &&
374 devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
375 IRQF_SHARED, pdev->name, pdev) < 0) {
376 dev_warn(&pdev->dev, "interrupt not available.\n");
377 pdata->irq = -1;
378 }
379
380 if (pdata->irq >= 0) {
381 device_init_wakeup(&pdev->dev, 1);
382 ret = dev_pm_set_wake_irq(&pdev->dev, pdata->irq);
383 if (ret)
384 dev_err(&pdev->dev, "failed to enable irq wake\n");
385 }
386
387 ret = devm_rtc_register_device(rtc);
388
389 return ret;
390}
391
392static struct platform_driver mxc_rtc_driver = {
393 .driver = {
394 .name = "mxc_rtc",
395 .of_match_table = imx_rtc_dt_ids,
396 },
397 .probe = mxc_rtc_probe,
398};
399
400module_platform_driver(mxc_rtc_driver)
401
402MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
403MODULE_DESCRIPTION("RTC driver for Freescale MXC");
404MODULE_LICENSE("GPL");
405