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12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/platform_device.h>
15#include <linux/slab.h>
16#include <linux/rtc.h>
17#include <linux/delay.h>
18#include <linux/io.h>
19#include <linux/bcd.h>
20
21
22#define REG_RTC_INIR 0x00
23#define REG_RTC_AER 0x04
24#define REG_RTC_FCR 0x08
25#define REG_RTC_TLR 0x0C
26#define REG_RTC_CLR 0x10
27#define REG_RTC_TSSR 0x14
28#define REG_RTC_DWR 0x18
29#define REG_RTC_TAR 0x1C
30#define REG_RTC_CAR 0x20
31#define REG_RTC_LIR 0x24
32#define REG_RTC_RIER 0x28
33#define REG_RTC_RIIR 0x2C
34#define REG_RTC_TTR 0x30
35
36#define RTCSET 0x01
37#define AERRWENB 0x10000
38#define INIRRESET 0xa5eb1357
39#define AERPOWERON 0xA965
40#define AERPOWEROFF 0x0000
41#define LEAPYEAR 0x0001
42#define TICKENB 0x80
43#define TICKINTENB 0x0002
44#define ALARMINTENB 0x0001
45#define MODE24 0x0001
46
47struct nuc900_rtc {
48 int irq_num;
49 void __iomem *rtc_reg;
50 struct rtc_device *rtcdev;
51};
52
53struct nuc900_bcd_time {
54 int bcd_sec;
55 int bcd_min;
56 int bcd_hour;
57 int bcd_mday;
58 int bcd_mon;
59 int bcd_year;
60};
61
62static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
63{
64 struct nuc900_rtc *rtc = _rtc;
65 unsigned long events = 0, rtc_irq;
66
67 rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);
68
69 if (rtc_irq & ALARMINTENB) {
70 rtc_irq &= ~ALARMINTENB;
71 __raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
72 events |= RTC_AF | RTC_IRQF;
73 }
74
75 if (rtc_irq & TICKINTENB) {
76 rtc_irq &= ~TICKINTENB;
77 __raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
78 events |= RTC_UF | RTC_IRQF;
79 }
80
81 rtc_update_irq(rtc->rtcdev, 1, events);
82
83 return IRQ_HANDLED;
84}
85
86static int *check_rtc_access_enable(struct nuc900_rtc *nuc900_rtc)
87{
88 unsigned int timeout = 0x1000;
89 __raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);
90
91 mdelay(10);
92
93 __raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);
94
95 while (!(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
96 && timeout--)
97 mdelay(1);
98
99 if (!timeout)
100 return ERR_PTR(-EPERM);
101
102 return 0;
103}
104
105static int 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 return rtc_valid_tm(tm);
117}
118
119static void nuc900_rtc_bin2bcd(struct device *dev, 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
125 if (settm->tm_year < 100) {
126 dev_warn(dev, "The year will be between 1970-1999, right?\n");
127 gettm->bcd_year = bin2bcd(settm->tm_year) << 16;
128 } else {
129 gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
130 }
131
132 gettm->bcd_sec = bin2bcd(settm->tm_sec) << 0;
133 gettm->bcd_min = bin2bcd(settm->tm_min) << 8;
134 gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
135}
136
137static int nuc900_update_irq_enable(struct device *dev, unsigned int enabled)
138{
139 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
140
141 if (enabled)
142 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
143 (TICKINTENB), rtc->rtc_reg + REG_RTC_RIER);
144 else
145 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
146 (~TICKINTENB), rtc->rtc_reg + REG_RTC_RIER);
147
148 return 0;
149}
150
151static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
152{
153 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
154
155 if (enabled)
156 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
157 (ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
158 else
159 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
160 (~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
161
162 return 0;
163}
164
165static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
166{
167 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
168 unsigned int timeval, clrval;
169
170 timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
171 clrval = __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
172
173 return nuc900_rtc_bcd2bin(timeval, clrval, tm);
174}
175
176static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
177{
178 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
179 struct nuc900_bcd_time gettm;
180 unsigned long val;
181 int *err;
182
183 nuc900_rtc_bin2bcd(dev, tm, &gettm);
184
185 err = check_rtc_access_enable(rtc);
186 if (IS_ERR(err))
187 return PTR_ERR(err);
188
189 val = gettm.bcd_mday | gettm.bcd_mon | gettm.bcd_year;
190 __raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
191
192 val = gettm.bcd_sec | gettm.bcd_min | gettm.bcd_hour;
193 __raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
194
195 return 0;
196}
197
198static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
199{
200 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
201 unsigned int timeval, carval;
202
203 timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
204 carval = __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
205
206 return nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
207}
208
209static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
210{
211 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
212 struct nuc900_bcd_time tm;
213 unsigned long val;
214 int *err;
215
216 nuc900_rtc_bin2bcd(dev, &alrm->time, &tm);
217
218 err = check_rtc_access_enable(rtc);
219 if (IS_ERR(err))
220 return PTR_ERR(err);
221
222 val = tm.bcd_mday | tm.bcd_mon | tm.bcd_year;
223 __raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
224
225 val = tm.bcd_sec | tm.bcd_min | tm.bcd_hour;
226 __raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
227
228 return 0;
229}
230
231static struct rtc_class_ops nuc900_rtc_ops = {
232 .read_time = nuc900_rtc_read_time,
233 .set_time = nuc900_rtc_set_time,
234 .read_alarm = nuc900_rtc_read_alarm,
235 .set_alarm = nuc900_rtc_set_alarm,
236 .alarm_irq_enable = nuc900_alarm_irq_enable,
237 .update_irq_enable = nuc900_update_irq_enable,
238};
239
240static int __devinit nuc900_rtc_probe(struct platform_device *pdev)
241{
242 struct resource *res;
243 struct nuc900_rtc *nuc900_rtc;
244 int err = 0;
245
246 nuc900_rtc = kzalloc(sizeof(struct nuc900_rtc), GFP_KERNEL);
247 if (!nuc900_rtc) {
248 dev_err(&pdev->dev, "kzalloc nuc900_rtc failed\n");
249 return -ENOMEM;
250 }
251 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
252 if (!res) {
253 dev_err(&pdev->dev, "platform_get_resource failed\n");
254 err = -ENXIO;
255 goto fail1;
256 }
257
258 if (!request_mem_region(res->start, resource_size(res),
259 pdev->name)) {
260 dev_err(&pdev->dev, "request_mem_region failed\n");
261 err = -EBUSY;
262 goto fail1;
263 }
264
265 nuc900_rtc->rtc_reg = ioremap(res->start, resource_size(res));
266 if (!nuc900_rtc->rtc_reg) {
267 dev_err(&pdev->dev, "ioremap rtc_reg failed\n");
268 err = -ENOMEM;
269 goto fail2;
270 }
271
272 platform_set_drvdata(pdev, nuc900_rtc);
273
274 nuc900_rtc->rtcdev = rtc_device_register(pdev->name, &pdev->dev,
275 &nuc900_rtc_ops, THIS_MODULE);
276 if (IS_ERR(nuc900_rtc->rtcdev)) {
277 dev_err(&pdev->dev, "rtc device register failed\n");
278 err = PTR_ERR(nuc900_rtc->rtcdev);
279 goto fail3;
280 }
281
282 __raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) | MODE24,
283 nuc900_rtc->rtc_reg + REG_RTC_TSSR);
284
285 nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
286 if (request_irq(nuc900_rtc->irq_num, nuc900_rtc_interrupt,
287 IRQF_DISABLED, "nuc900rtc", nuc900_rtc)) {
288 dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
289 err = -EBUSY;
290 goto fail4;
291 }
292
293 return 0;
294
295fail4: rtc_device_unregister(nuc900_rtc->rtcdev);
296fail3: iounmap(nuc900_rtc->rtc_reg);
297fail2: release_mem_region(res->start, resource_size(res));
298fail1: kfree(nuc900_rtc);
299 return err;
300}
301
302static int __devexit nuc900_rtc_remove(struct platform_device *pdev)
303{
304 struct nuc900_rtc *nuc900_rtc = platform_get_drvdata(pdev);
305 struct resource *res;
306
307 free_irq(nuc900_rtc->irq_num, nuc900_rtc);
308 rtc_device_unregister(nuc900_rtc->rtcdev);
309 iounmap(nuc900_rtc->rtc_reg);
310
311 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
312 release_mem_region(res->start, resource_size(res));
313
314 kfree(nuc900_rtc);
315
316 platform_set_drvdata(pdev, NULL);
317
318 return 0;
319}
320
321static struct platform_driver nuc900_rtc_driver = {
322 .remove = __devexit_p(nuc900_rtc_remove),
323 .driver = {
324 .name = "nuc900-rtc",
325 .owner = THIS_MODULE,
326 },
327};
328
329static int __init nuc900_rtc_init(void)
330{
331 return platform_driver_probe(&nuc900_rtc_driver, nuc900_rtc_probe);
332}
333
334static void __exit nuc900_rtc_exit(void)
335{
336 platform_driver_unregister(&nuc900_rtc_driver);
337}
338
339module_init(nuc900_rtc_init);
340module_exit(nuc900_rtc_exit);
341
342MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
343MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
344MODULE_LICENSE("GPL");
345MODULE_ALIAS("platform:nuc900-rtc");
346
