tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/slab.h>
16#include <linux/rtc.h>
17#include <linux/delay.h>
18#include <linux/io.h>
19#include <linux/bcd.h>
20
21/* RTC Control Registers */
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 i;
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 for (i = 0; i < 1000; i++) {
96 if (__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
97 return 0;
98 }
99
100 if ((__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB) == 0x0)
101 return ERR_PTR(-ENODEV);
102
103 return ERR_PTR(-EPERM);
104}
105
106static void nuc900_rtc_bcd2bin(unsigned int timereg,
107 unsigned int calreg, struct rtc_time *tm)
108{
109 tm->tm_mday = bcd2bin(calreg >> 0);
110 tm->tm_mon = bcd2bin(calreg >> 8);
111 tm->tm_year = bcd2bin(calreg >> 16) + 100;
112
113 tm->tm_sec = bcd2bin(timereg >> 0);
114 tm->tm_min = bcd2bin(timereg >> 8);
115 tm->tm_hour = bcd2bin(timereg >> 16);
116
117 rtc_valid_tm(tm);
118}
119
120static void nuc900_rtc_bin2bcd(struct rtc_time *settm,
121 struct nuc900_bcd_time *gettm)
122{
123 gettm->bcd_mday = bin2bcd(settm->tm_mday) << 0;
124 gettm->bcd_mon = bin2bcd(settm->tm_mon) << 8;
125 gettm->bcd_year = bin2bcd(settm->tm_year - 100) << 16;
126
127 gettm->bcd_sec = bin2bcd(settm->tm_sec) << 0;
128 gettm->bcd_min = bin2bcd(settm->tm_min) << 8;
129 gettm->bcd_hour = bin2bcd(settm->tm_hour) << 16;
130}
131
132static int nuc900_update_irq_enable(struct device *dev, unsigned int enabled)
133{
134 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
135
136 if (enabled)
137 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
138 (TICKINTENB), rtc->rtc_reg + REG_RTC_RIER);
139 else
140 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
141 (~TICKINTENB), rtc->rtc_reg + REG_RTC_RIER);
142
143 return 0;
144}
145
146static int nuc900_alarm_irq_enable(struct device *dev, unsigned int enabled)
147{
148 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
149
150 if (enabled)
151 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
152 (ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
153 else
154 __raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)&
155 (~ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
156
157 return 0;
158}
159
160static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
161{
162 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
163 unsigned int timeval, clrval;
164
165 timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
166 clrval = __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
167
168 nuc900_rtc_bcd2bin(timeval, clrval, tm);
169
170 return 0;
171}
172
173static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
174{
175 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
176 struct nuc900_bcd_time gettm;
177 unsigned long val;
178 int *err;
179
180 nuc900_rtc_bin2bcd(tm, &gettm);
181
182 err = check_rtc_access_enable(rtc);
183 if (IS_ERR(err))
184 return PTR_ERR(err);
185
186 val = gettm.bcd_mday | gettm.bcd_mon | gettm.bcd_year;
187 __raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
188
189 val = gettm.bcd_sec | gettm.bcd_min | gettm.bcd_hour;
190 __raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
191
192 return 0;
193}
194
195static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
196{
197 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
198 unsigned int timeval, carval;
199
200 timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
201 carval = __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
202
203 nuc900_rtc_bcd2bin(timeval, carval, &alrm->time);
204
205 return 0;
206}
207
208static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
209{
210 struct nuc900_rtc *rtc = dev_get_drvdata(dev);
211 struct nuc900_bcd_time tm;
212 unsigned long val;
213 int *err;
214
215 nuc900_rtc_bin2bcd(&alrm->time, &tm);
216
217 err = check_rtc_access_enable(rtc);
218 if (IS_ERR(err))
219 return PTR_ERR(err);
220
221 val = tm.bcd_mday | tm.bcd_mon | tm.bcd_year;
222 __raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
223
224 val = tm.bcd_sec | tm.bcd_min | tm.bcd_hour;
225 __raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
226
227 return 0;
228}
229
230static struct rtc_class_ops nuc900_rtc_ops = {
231 .read_time = nuc900_rtc_read_time,
232 .set_time = nuc900_rtc_set_time,
233 .read_alarm = nuc900_rtc_read_alarm,
234 .set_alarm = nuc900_rtc_set_alarm,
235 .alarm_irq_enable = nuc900_alarm_irq_enable,
236 .update_irq_enable = nuc900_update_irq_enable,
237};
238
239static int __devinit nuc900_rtc_probe(struct platform_device *pdev)
240{
241 struct resource *res;
242 struct nuc900_rtc *nuc900_rtc;
243 int err = 0;
244
245 nuc900_rtc = kzalloc(sizeof(struct nuc900_rtc), GFP_KERNEL);
246 if (!nuc900_rtc) {
247 dev_err(&pdev->dev, "kzalloc nuc900_rtc failed\n");
248 return -ENOMEM;
249 }
250 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
251 if (!res) {
252 dev_err(&pdev->dev, "platform_get_resource failed\n");
253 err = -ENXIO;
254 goto fail1;
255 }
256
257 if (!request_mem_region(res->start, resource_size(res),
258 pdev->name)) {
259 dev_err(&pdev->dev, "request_mem_region failed\n");
260 err = -EBUSY;
261 goto fail1;
262 }
263
264 nuc900_rtc->rtc_reg = ioremap(res->start, resource_size(res));
265 if (!nuc900_rtc->rtc_reg) {
266 dev_err(&pdev->dev, "ioremap rtc_reg failed\n");
267 err = -ENOMEM;
268 goto fail2;
269 }
270
271 nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
272 if (request_irq(nuc900_rtc->irq_num, nuc900_rtc_interrupt,
273 IRQF_DISABLED, "nuc900rtc", nuc900_rtc)) {
274 dev_err(&pdev->dev, "NUC900 RTC request irq failed\n");
275 err = -EBUSY;
276 goto fail3;
277 }
278
279 nuc900_rtc->rtcdev = rtc_device_register(pdev->name, &pdev->dev,
280 &nuc900_rtc_ops, THIS_MODULE);
281 if (IS_ERR(nuc900_rtc->rtcdev)) {
282 dev_err(&pdev->dev, "rtc device register faild\n");
283 err = PTR_ERR(nuc900_rtc->rtcdev);
284 goto fail4;
285 }
286
287 platform_set_drvdata(pdev, nuc900_rtc);
288 __raw_writel(__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_TSSR) | MODE24,
289 nuc900_rtc->rtc_reg + REG_RTC_TSSR);
290
291 return 0;
292
293fail4: free_irq(nuc900_rtc->irq_num, nuc900_rtc);
294fail3: iounmap(nuc900_rtc->rtc_reg);
295fail2: release_mem_region(res->start, resource_size(res));
296fail1: kfree(nuc900_rtc);
297 return err;
298}
299
300static int __devexit nuc900_rtc_remove(struct platform_device *pdev)
301{
302 struct nuc900_rtc *nuc900_rtc = platform_get_drvdata(pdev);
303 struct resource *res;
304
305 rtc_device_unregister(nuc900_rtc->rtcdev);
306 free_irq(nuc900_rtc->irq_num, nuc900_rtc);
307 iounmap(nuc900_rtc->rtc_reg);
308
309 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
310 release_mem_region(res->start, resource_size(res));
311
312 kfree(nuc900_rtc);
313
314 platform_set_drvdata(pdev, NULL);
315
316 return 0;
317}
318
319static struct platform_driver nuc900_rtc_driver = {
320 .remove = __devexit_p(nuc900_rtc_remove),
321 .driver = {
322 .name = "nuc900-rtc",
323 .owner = THIS_MODULE,
324 },
325};
326
327static int __init nuc900_rtc_init(void)
328{
329 return platform_driver_probe(&nuc900_rtc_driver, nuc900_rtc_probe);
330}
331
332static void __exit nuc900_rtc_exit(void)
333{
334 platform_driver_unregister(&nuc900_rtc_driver);
335}
336
337module_init(nuc900_rtc_init);
338module_exit(nuc900_rtc_exit);
339
340MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
341MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
342MODULE_LICENSE("GPL");
343MODULE_ALIAS("platform:nuc900-rtc");