ARM: tegra30: pm: flush L1 data before exit coherency on secondary CPU
[linux-2.6.git] / drivers / rtc / rtc-ricoh583.c
1 /*
2  * drivers/rtc/rtc_ricoh583.c
3  *
4  * rtc driver for ricoh rc5t583 pmu
5  *
6  * copyright (c) 2011, nvidia corporation.
7  *
8  * this program is free software; you can redistribute it and/or modify
9  * it under the terms of the gnu general public license as published by
10  * the free software foundation; either version 2 of the license, or
11  * (at your option) any later version.
12  *
13  * this program is distributed in the hope that it will be useful, but without
14  * any warranty; without even the implied warranty of merchantability or
15  * fitness for a particular purpose.  see the gnu general public license for
16  * more details.
17  *
18  * you should have received a copy of the gnu general public license along
19  * with this program; if not, write to the free software foundation, inc.,
20  * 51 franklin street, fifth floor, boston, ma  02110-1301, usa.
21  */
22
23 /* #define debug                1 */
24 /* #define verbose_debug        1 */
25
26 #include <linux/device.h>
27 #include <linux/err.h>
28 #include <linux/init.h>
29 #include <linux/kernel.h>
30 #include <linux/mfd/ricoh583.h>
31 #include <linux/platform_device.h>
32 #include <linux/rtc.h>
33 #include <linux/slab.h>
34
35 #define rtc_ctrl1               0xED
36 #define rtc_ctrl2               0xEE
37 #define rtc_seconds_reg         0xE0
38 #define rtc_alarm_y             0xF0
39 #define rtc_adjust              0xE7
40
41 /*
42 linux rtc driver refers 1900 as base year in many calculations.
43 (e.g. refer drivers/rtc/rtc-lib.c)
44 */
45 #define os_ref_year 1900
46
47 /*
48         pmu rtc have only 2 nibbles to store year information, so using an
49         offset of 100 to set the base year as 2000 for our driver.
50 */
51 #define rtc_year_offset 100
52
53 struct ricoh583_rtc {
54         unsigned long           epoch_start;
55         int                     irq;
56         struct rtc_device       *rtc;
57         bool                    irq_en;
58 };
59
60 static int ricoh583_read_regs(struct device *dev, int reg, int len,
61         uint8_t *val)
62 {
63         int ret;
64
65         ret = ricoh583_bulk_reads(dev->parent, reg, len, val);
66         if (ret < 0) {
67                 dev_err(dev->parent, "\n %s failed reading from 0x%02x\n",
68                         __func__, reg);
69                 WARN_ON(1);
70         }
71         return ret;
72 }
73
74 static int ricoh583_write_regs(struct device *dev, int reg, int len,
75         uint8_t *val)
76 {
77         int ret;
78         ret = ricoh583_bulk_writes(dev->parent, reg, len, val);
79         if (ret < 0) {
80                 dev_err(dev->parent, "\n %s failed writing\n", __func__);
81                 WARN_ON(1);
82         }
83
84         return ret;
85 }
86
87 static int ricoh583_rtc_valid_tm(struct device *dev, struct rtc_time *tm)
88 {
89         if (tm->tm_year >= (rtc_year_offset + 99)
90                 || tm->tm_mon > 12
91                 || tm->tm_mday < 1
92                 || tm->tm_mday > rtc_month_days(tm->tm_mon,
93                         tm->tm_year + os_ref_year)
94                 || tm->tm_hour >= 24
95                 || tm->tm_min >= 60
96                 || tm->tm_sec >= 60) {
97                 dev_err(dev->parent, "\n returning error due to time"
98                 "%d/%d/%d %d:%d:%d", tm->tm_mon, tm->tm_mday,
99                 tm->tm_year, tm->tm_hour, tm->tm_min, tm->tm_sec);
100                 return -EINVAL;
101         }
102         return 0;
103 }
104
105 static u8 dec2bcd(u8 dec)
106 {
107         return ((dec/10)<<4)+(dec%10);
108 }
109
110 static u8 bcd2dec(u8 bcd)
111 {
112         return (bcd >> 4)*10+(bcd & 0xf);
113 }
114
115 static void convert_bcd_to_decimal(u8 *buf, u8 len)
116 {
117         int i = 0;
118         for (i = 0; i < len; i++)
119                 buf[i] = bcd2dec(buf[i]);
120 }
121
122 static void convert_decimal_to_bcd(u8 *buf, u8 len)
123 {
124         int i = 0;
125         for (i = 0; i < len; i++)
126                 buf[i] = dec2bcd(buf[i]);
127 }
128
129 static void print_time(struct device *dev, struct rtc_time *tm)
130 {
131         dev_info(dev, "rtc-time : %d/%d/%d %d:%d\n",
132                 (tm->tm_mon + 1), tm->tm_mday, (tm->tm_year + os_ref_year),
133                 tm->tm_hour, tm->tm_min);
134 }
135
136 static int ricoh583_rtc_read_time(struct device *dev, struct rtc_time *tm)
137 {
138         u8 buff[7];
139         int err;
140         err = ricoh583_read_regs(dev, rtc_seconds_reg, sizeof(buff), buff);
141         if (err < 0) {
142                 dev_err(dev, "\n %s :: failed to read time\n", __FILE__);
143                 return err;
144         }
145         convert_bcd_to_decimal(buff, sizeof(buff));
146         tm->tm_sec  = buff[0];
147         tm->tm_min  = buff[1];
148         tm->tm_hour = buff[2];
149         tm->tm_wday = buff[3];
150         tm->tm_mday = buff[4];
151         tm->tm_mon  = buff[5] - 1;
152         tm->tm_year = buff[6] + rtc_year_offset;
153         print_time(dev, tm);
154         return ricoh583_rtc_valid_tm(dev, tm);
155 }
156
157 static int ricoh583_rtc_set_time(struct device *dev, struct rtc_time *tm)
158 {
159         u8 buff[7];
160         int err;
161
162         print_time(dev, tm);
163         buff[0] = tm->tm_sec;
164         buff[1] = tm->tm_min;
165         buff[2] = tm->tm_hour;
166         buff[3] = tm->tm_wday;
167         buff[4] = tm->tm_mday;
168         buff[5] = tm->tm_mon + 1;
169         buff[6] = tm->tm_year - rtc_year_offset;
170
171         convert_decimal_to_bcd(buff, sizeof(buff));
172         err = ricoh583_write_regs(dev, rtc_seconds_reg, sizeof(buff), buff);
173         if (err < 0) {
174                 dev_err(dev->parent, "\n failed to program new time\n");
175                 return err;
176         }
177
178         return 0;
179 }
180 static int ricoh583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm);
181
182 static int ricoh583_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
183 {
184         struct ricoh583_rtc *rtc = dev_get_drvdata(dev);
185         unsigned long seconds;
186         u8 buff[5];
187         int err;
188         struct rtc_time tm;
189
190         if (rtc->irq == -1)
191                 return -EIO;
192
193         rtc_tm_to_time(&alrm->time, &seconds);
194         ricoh583_rtc_read_time(dev, &tm);
195         rtc_tm_to_time(&tm, &rtc->epoch_start);
196         /*
197                 work around: As YAL does not provide the seconds register,
198                 program minute register to next minute, in cases when alarm
199                 is requested within a minute from the current time.
200         */
201         if (seconds - rtc->epoch_start < 60)
202                 alrm->time.tm_min += 1;
203         dev_info(dev->parent, "\n setting alarm to requested time::\n");
204         print_time(dev->parent, &alrm->time);
205
206         if (WARN_ON(alrm->enabled && (seconds < rtc->epoch_start))) {
207                 dev_err(dev->parent, "\n can't set alarm to requested time\n");
208                 return -EINVAL;
209         }
210
211         if (alrm->enabled && !rtc->irq_en)
212                 rtc->irq_en = true;
213         else if (!alrm->enabled && rtc->irq_en)
214                 rtc->irq_en = false;
215
216         buff[0] = alrm->time.tm_min;
217         buff[1] = alrm->time.tm_hour;
218         buff[2] = alrm->time.tm_mday;
219         buff[3] = alrm->time.tm_mon + 1;
220         buff[4] = alrm->time.tm_year - rtc_year_offset;
221         convert_decimal_to_bcd(buff, sizeof(buff));
222         err = ricoh583_write_regs(dev, rtc_alarm_y, sizeof(buff), buff);
223         if (err) {
224                 dev_err(dev->parent, "\n unable to set alarm\n");
225                 return -EBUSY;
226         }
227         buff[0] = 0x20; /* to enable alarm_y */
228         buff[1] = 0x20; /* to enable 24-hour format */
229         err = ricoh583_write_regs(dev, rtc_ctrl1, 2, buff);
230         if (err) {
231                 dev_err(dev, "failed programming rtc ctrl regs\n");
232                 return -EBUSY;
233         }
234 return err;
235 }
236
237 static int ricoh583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
238 {
239         u8 buff[5];
240         int err;
241
242         err = ricoh583_read_regs(dev, rtc_alarm_y, sizeof(buff), buff);
243         if (err)
244                 return err;
245         convert_bcd_to_decimal(buff, sizeof(buff));
246
247         alrm->time.tm_min  = buff[0];
248         alrm->time.tm_hour = buff[1];
249         alrm->time.tm_mday = buff[2];
250         alrm->time.tm_mon  = buff[3] - 1;
251         alrm->time.tm_year = buff[4] + rtc_year_offset;
252
253         dev_info(dev->parent, "\n getting alarm time::\n");
254         print_time(dev, &alrm->time);
255
256         return 0;
257 }
258
259 static const struct rtc_class_ops ricoh583_rtc_ops = {
260         .read_time      = ricoh583_rtc_read_time,
261         .set_time       = ricoh583_rtc_set_time,
262         .set_alarm      = ricoh583_rtc_set_alarm,
263         .read_alarm     = ricoh583_rtc_read_alarm,
264 };
265
266 static irqreturn_t ricoh583_rtc_irq(int irq, void *data)
267 {
268         struct device *dev = data;
269         struct ricoh583_rtc *rtc = dev_get_drvdata(dev);
270         u8 reg;
271         int err;
272
273         /* clear alarm-Y status bits.*/
274         err = ricoh583_read_regs(dev, rtc_ctrl2, 1, &reg);
275         if (err) {
276                 dev_err(dev->parent, "unable to read rtc_ctrl2 reg\n");
277                 return -EBUSY;
278         }
279         reg &= ~0x8;
280         err = ricoh583_write_regs(dev, rtc_ctrl2, 1, &reg);
281         if (err) {
282                 dev_err(dev->parent, "unable to program rtc_status reg\n");
283                 return -EBUSY;
284         }
285
286         rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
287         return IRQ_HANDLED;
288 }
289
290 static int __devinit ricoh583_rtc_probe(struct platform_device *pdev)
291 {
292         struct ricoh583_rtc_platform_data *pdata = pdev->dev.platform_data;
293         struct ricoh583_rtc *rtc;
294         struct rtc_time tm;
295         int err;
296         u8 reg[2];
297         rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
298
299         if (!rtc)
300                 return -ENOMEM;
301
302         rtc->irq = -1;
303
304         if (!pdata) {
305                 dev_err(&pdev->dev, "no platform_data specified\n");
306                 return -EINVAL;
307         }
308
309         if (pdata->irq < 0)
310                 dev_err(&pdev->dev, "\n no irq specified, wakeup is disabled\n");
311
312         dev_set_drvdata(&pdev->dev, rtc);
313         device_init_wakeup(&pdev->dev, 1);
314         rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
315                                        &ricoh583_rtc_ops, THIS_MODULE);
316
317         if (IS_ERR(rtc->rtc)) {
318                 err = PTR_ERR(rtc->rtc);
319                 goto fail;
320         }
321         reg[0] =  0; /* clearing RTC Adjust register */
322         err = ricoh583_write_regs(&pdev->dev, rtc_adjust, 1, reg);
323         if (err) {
324                 dev_err(&pdev->dev, "unable to program rtc_adjust reg\n");
325                 return -EBUSY;
326         }
327
328         reg[0] = 0x20; /* to enable alarm_y */
329         reg[1] = 0x20; /* to enable 24-hour format */
330         err = ricoh583_write_regs(&pdev->dev, rtc_ctrl1, 2, reg);
331         if (err) {
332                 dev_err(&pdev->dev, "failed rtc setup\n");
333                 return -EBUSY;
334         }
335
336         ricoh583_rtc_read_time(&pdev->dev, &tm);
337         if (ricoh583_rtc_valid_tm(&pdev->dev, &tm)) {
338                 if (pdata->time.tm_year < 2000 || pdata->time.tm_year > 2100) {
339                         memset(&pdata->time, 0, sizeof(pdata->time));
340                         pdata->time.tm_year = rtc_year_offset;
341                         pdata->time.tm_mday = 1;
342                 } else
343                 pdata->time.tm_year -= os_ref_year;
344                 ricoh583_rtc_set_time(&pdev->dev, &pdata->time);
345         }
346         if (pdata && (pdata->irq >= 0)) {
347                 rtc->irq = pdata->irq;
348                 err = request_threaded_irq(pdata->irq, NULL, ricoh583_rtc_irq,
349                                         IRQF_ONESHOT, "rtc_ricoh583",
350                                         &pdev->dev);
351                 if (err) {
352                         dev_err(&pdev->dev, "request IRQ:%d fail\n", rtc->irq);
353                         rtc->irq = -1;
354                 } else {
355                         device_init_wakeup(&pdev->dev, 1);
356                         enable_irq_wake(rtc->irq);
357                 }
358         }
359         return 0;
360
361 fail:
362         if (!IS_ERR_OR_NULL(rtc->rtc))
363                 rtc_device_unregister(rtc->rtc);
364         kfree(rtc);
365         return err;
366 }
367
368 static int __devexit ricoh583_rtc_remove(struct platform_device *pdev)
369 {
370         struct ricoh583_rtc *rtc = dev_get_drvdata(&pdev->dev);
371
372         if (rtc->irq != -1)
373                 free_irq(rtc->irq, rtc);
374         rtc_device_unregister(rtc->rtc);
375         kfree(rtc);
376         return 0;
377 }
378
379 static struct platform_driver ricoh583_rtc_driver = {
380         .driver = {
381                 .name   = "rtc_ricoh583",
382                 .owner  = THIS_MODULE,
383         },
384         .probe  = ricoh583_rtc_probe,
385         .remove = __devexit_p(ricoh583_rtc_remove),
386 };
387
388 static int __init ricoh583_rtc_init(void)
389 {
390         return platform_driver_register(&ricoh583_rtc_driver);
391 }
392 module_init(ricoh583_rtc_init);
393
394 static void __exit ricoh583_rtc_exit(void)
395 {
396         platform_driver_unregister(&ricoh583_rtc_driver);
397 }
398 module_exit(ricoh583_rtc_exit);
399
400 MODULE_DESCRIPTION("RICOH PMU ricoh583 RTC driver");
401 MODULE_AUTHOR("NVIDIA Corporation");
402 MODULE_LICENSE("GPL");
403 MODULE_ALIAS("platform:rtc_ricoh583");