vhost-net: switch to smp barriers
[safe/jmp/linux-2.6] / drivers / rtc / rtc-nuc900.c
1 /*
2  * Copyright (c) 2008-2009 Nuvoton technology corporation.
3  *
4  * Wan ZongShun <mcuos.com@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation;version 2 of the License.
9  *
10  */
11
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/platform_device.h>
15 #include <linux/rtc.h>
16 #include <linux/delay.h>
17 #include <linux/io.h>
18 #include <linux/bcd.h>
19
20 /* RTC Control Registers */
21 #define REG_RTC_INIR            0x00
22 #define REG_RTC_AER             0x04
23 #define REG_RTC_FCR             0x08
24 #define REG_RTC_TLR             0x0C
25 #define REG_RTC_CLR             0x10
26 #define REG_RTC_TSSR            0x14
27 #define REG_RTC_DWR             0x18
28 #define REG_RTC_TAR             0x1C
29 #define REG_RTC_CAR             0x20
30 #define REG_RTC_LIR             0x24
31 #define REG_RTC_RIER            0x28
32 #define REG_RTC_RIIR            0x2C
33 #define REG_RTC_TTR             0x30
34
35 #define RTCSET                  0x01
36 #define AERRWENB                0x10000
37 #define INIRRESET               0xa5eb1357
38 #define AERPOWERON              0xA965
39 #define AERPOWEROFF             0x0000
40 #define LEAPYEAR                0x0001
41 #define TICKENB                 0x80
42 #define TICKINTENB              0x0002
43 #define ALARMINTENB             0x0001
44 #define MODE24                  0x0001
45
46 struct nuc900_rtc {
47         int                     irq_num;
48         void __iomem            *rtc_reg;
49         struct rtc_device       *rtcdev;
50 };
51
52 struct nuc900_bcd_time {
53         int bcd_sec;
54         int bcd_min;
55         int bcd_hour;
56         int bcd_mday;
57         int bcd_mon;
58         int bcd_year;
59 };
60
61 static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
62 {
63         struct nuc900_rtc *rtc = _rtc;
64         unsigned long events = 0, rtc_irq;
65
66         rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);
67
68         if (rtc_irq & ALARMINTENB) {
69                 rtc_irq &= ~ALARMINTENB;
70                 __raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
71                 events |= RTC_AF | RTC_IRQF;
72         }
73
74         if (rtc_irq & TICKINTENB) {
75                 rtc_irq &= ~TICKINTENB;
76                 __raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
77                 events |= RTC_UF | RTC_IRQF;
78         }
79
80         rtc_update_irq(rtc->rtcdev, 1, events);
81
82         return IRQ_HANDLED;
83 }
84
85 static int *check_rtc_access_enable(struct nuc900_rtc *nuc900_rtc)
86 {
87         unsigned int i;
88         __raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);
89
90         mdelay(10);
91
92         __raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);
93
94         for (i = 0; i < 1000; i++) {
95                 if (__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
96                         return 0;
97         }
98
99         if ((__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB) == 0x0)
100                 return ERR_PTR(-ENODEV);
101
102         return ERR_PTR(-EPERM);
103 }
104
105 static void nuc900_rtc_bcd2bin(unsigned int timereg,
106                                 unsigned int calreg, struct rtc_time *tm)
107 {
108         tm->tm_mday     = bcd2bin(calreg >> 0);
109         tm->tm_mon      = bcd2bin(calreg >> 8);
110         tm->tm_year     = bcd2bin(calreg >> 16) + 100;
111
112         tm->tm_sec      = bcd2bin(timereg >> 0);
113         tm->tm_min      = bcd2bin(timereg >> 8);
114         tm->tm_hour     = bcd2bin(timereg >> 16);
115
116         rtc_valid_tm(tm);
117 }
118
119 static void nuc900_rtc_bin2bcd(struct rtc_time *settm,
120                                                 struct nuc900_bcd_time *gettm)
121 {
122         gettm->bcd_mday = bin2bcd(settm->tm_mday) << 0;
123         gettm->bcd_mon  = bin2bcd(settm->tm_mon) << 8;
124         gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
125
126         gettm->bcd_sec  = bin2bcd(settm->tm_sec) << 0;
127         gettm->bcd_min  = bin2bcd(settm->tm_min) << 8;
128         gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
129 }
130
131 static int nuc900_update_irq_enable(struct device *dev, unsigned int enabled)
132 {
133         struct nuc900_rtc *rtc = dev_get_drvdata(dev);
134
135         if (enabled)
136                 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
137                                 (TICKINTENB), rtc->rtc_reg + REG_RTC_RIER);
138         else
139                 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
140                                 (~TICKINTENB), rtc->rtc_reg + REG_RTC_RIER);
141
142         return 0;
143 }
144
145 static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
146 {
147         struct nuc900_rtc *rtc = dev_get_drvdata(dev);
148
149         if (enabled)
150                 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
151                                 (ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
152         else
153                 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
154                                 (~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
155
156         return 0;
157 }
158
159 static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
160 {
161         struct nuc900_rtc *rtc = dev_get_drvdata(dev);
162         unsigned int timeval, clrval;
163
164         timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
165         clrval  = __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
166
167         nuc900_rtc_bcd2bin(timeval, clrval, tm);
168
169         return 0;
170 }
171
172 static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
173 {
174         struct nuc900_rtc *rtc = dev_get_drvdata(dev);
175         struct nuc900_bcd_time gettm;
176         unsigned long val;
177         int *err;
178
179         nuc900_rtc_bin2bcd(tm, &gettm);
180
181         err = check_rtc_access_enable(rtc);
182         if (IS_ERR(err))
183                 return PTR_ERR(err);
184
185         val = gettm.bcd_mday | gettm.bcd_mon | gettm.bcd_year;
186         __raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
187
188         val = gettm.bcd_sec | gettm.bcd_min | gettm.bcd_hour;
189         __raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
190
191         return 0;
192 }
193
194 static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
195 {
196         struct nuc900_rtc *rtc = dev_get_drvdata(dev);
197         unsigned int timeval, carval;
198
199         timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
200         carval  = __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
201
202         nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
203
204         return 0;
205 }
206
207 static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
208 {
209         struct nuc900_rtc *rtc = dev_get_drvdata(dev);
210         struct nuc900_bcd_time tm;
211         unsigned long val;
212         int *err;
213
214         nuc900_rtc_bin2bcd(&alrm->time, &tm);
215
216         err = check_rtc_access_enable(rtc);
217         if (IS_ERR(err))
218                 return PTR_ERR(err);
219
220         val = tm.bcd_mday | tm.bcd_mon | tm.bcd_year;
221         __raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
222
223         val = tm.bcd_sec | tm.bcd_min | tm.bcd_hour;
224         __raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
225
226         return 0;
227 }
228
229 static struct rtc_class_ops nuc900_rtc_ops = {
230         .read_time = nuc900_rtc_read_time,
231         .set_time = nuc900_rtc_set_time,
232         .read_alarm = nuc900_rtc_read_alarm,
233         .set_alarm = nuc900_rtc_set_alarm,
234         .alarm_irq_enable = nuc900_alarm_irq_enable,
235         .update_irq_enable = nuc900_update_irq_enable,
236 };
237
238 static int __devinit nuc900_rtc_probe(struct platform_device *pdev)
239 {
240         struct resource *res;
241         struct nuc900_rtc *nuc900_rtc;
242         int err = 0;
243
244         nuc900_rtc = kzalloc(sizeof(struct nuc900_rtc), GFP_KERNEL);
245         if (!nuc900_rtc) {
246                 dev_err(&pdev->dev, "kzalloc nuc900_rtc failed\n");
247                 return -ENOMEM;
248         }
249         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
250         if (!res) {
251                 dev_err(&pdev->dev, "platform_get_resource failed\n");
252                 err = -ENXIO;
253                 goto fail1;
254         }
255
256         if (!request_mem_region(res->start, resource_size(res),
257                                 pdev->name)) {
258                 dev_err(&pdev->dev, "request_mem_region failed\n");
259                 err = -EBUSY;
260                 goto fail1;
261         }
262
263         nuc900_rtc->rtc_reg = ioremap(res->start, resource_size(res));
264         if (!nuc900_rtc->rtc_reg) {
265                 dev_err(&pdev->dev, "ioremap rtc_reg failed\n");
266                 err = -ENOMEM;
267                 goto fail2;
268         }
269
270         nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
271         if (request_irq(nuc900_rtc->irq_num, nuc900_rtc_interrupt,
272                                 IRQF_DISABLED, "nuc900rtc", nuc900_rtc)) {
273                 dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
274                 err = -EBUSY;
275                 goto fail3;
276         }
277
278         nuc900_rtc->rtcdev = rtc_device_register(pdev->name, &pdev->dev,
279                                                 &nuc900_rtc_ops, THIS_MODULE);
280         if (IS_ERR(nuc900_rtc->rtcdev)) {
281                 dev_err(&pdev->dev, "rtc device register faild\n");
282                 err = PTR_ERR(nuc900_rtc->rtcdev);
283                 goto fail4;
284         }
285
286         platform_set_drvdata(pdev, nuc900_rtc);
287         __raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) | MODE24,
288                                         nuc900_rtc->rtc_reg + REG_RTC_TSSR);
289
290         return 0;
291
292 fail4:  free_irq(nuc900_rtc->irq_num, nuc900_rtc);
293 fail3:  iounmap(nuc900_rtc->rtc_reg);
294 fail2:  release_mem_region(res->start, resource_size(res));
295 fail1:  kfree(nuc900_rtc);
296         return err;
297 }
298
299 static int __devexit nuc900_rtc_remove(struct platform_device *pdev)
300 {
301         struct nuc900_rtc *nuc900_rtc = platform_get_drvdata(pdev);
302         struct resource *res;
303
304         rtc_device_unregister(nuc900_rtc->rtcdev);
305         free_irq(nuc900_rtc->irq_num, nuc900_rtc);
306         iounmap(nuc900_rtc->rtc_reg);
307
308         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
309         release_mem_region(res->start, resource_size(res));
310
311         kfree(nuc900_rtc);
312
313         platform_set_drvdata(pdev, NULL);
314
315         return 0;
316 }
317
318 static struct platform_driver nuc900_rtc_driver = {
319         .remove         = __devexit_p(nuc900_rtc_remove),
320         .driver         = {
321                 .name   = "nuc900-rtc",
322                 .owner  = THIS_MODULE,
323         },
324 };
325
326 static int __init nuc900_rtc_init(void)
327 {
328         return platform_driver_probe(&nuc900_rtc_driver, nuc900_rtc_probe);
329 }
330
331 static void __exit nuc900_rtc_exit(void)
332 {
333         platform_driver_unregister(&nuc900_rtc_driver);
334 }
335
336 module_init(nuc900_rtc_init);
337 module_exit(nuc900_rtc_exit);
338
339 MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
340 MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
341 MODULE_LICENSE("GPL");
342 MODULE_ALIAS("platform:nuc900-rtc");