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14#include <linux/bcd.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/delay.h>
18#include <linux/jiffies.h>
19#include <linux/interrupt.h>
20#include <linux/rtc.h>
21#include <linux/platform_device.h>
22#include <linux/io.h>
23
24#define DRV_VERSION "0.1"
25
26#define RTC_REG_SIZE 0x20000
27#define RTC_OFFSET 0x1fff0
28
29#define RTC_FLAGS (RTC_OFFSET + 0)
30#define RTC_CENTURY (RTC_OFFSET + 1)
31#define RTC_SECONDS_ALARM (RTC_OFFSET + 2)
32#define RTC_MINUTES_ALARM (RTC_OFFSET + 3)
33#define RTC_HOURS_ALARM (RTC_OFFSET + 4)
34#define RTC_DATE_ALARM (RTC_OFFSET + 5)
35#define RTC_INTERRUPTS (RTC_OFFSET + 6)
36#define RTC_WATCHDOG (RTC_OFFSET + 7)
37#define RTC_CALIBRATION (RTC_OFFSET + 8)
38#define RTC_SECONDS (RTC_OFFSET + 9)
39#define RTC_MINUTES (RTC_OFFSET + 10)
40#define RTC_HOURS (RTC_OFFSET + 11)
41#define RTC_DAY (RTC_OFFSET + 12)
42#define RTC_DATE (RTC_OFFSET + 13)
43#define RTC_MONTH (RTC_OFFSET + 14)
44#define RTC_YEAR (RTC_OFFSET + 15)
45
46#define RTC_SECONDS_MASK 0x7f
47#define RTC_DAY_MASK 0x07
48#define RTC_CAL_MASK 0x3f
49
50
51#define RTC_STOP 0x80
52
53
54#define RTC_FLAGS_AF 0x40
55#define RTC_FLAGS_PF 0x20
56#define RTC_WRITE 0x02
57#define RTC_READ 0x01
58
59
60#define RTC_INTS_AIE 0x40
61
62struct rtc_plat_data {
63 struct rtc_device *rtc;
64 void __iomem *ioaddr;
65 unsigned long baseaddr;
66 unsigned long last_jiffies;
67 int irq;
68 unsigned int irqen;
69 int alrm_sec;
70 int alrm_min;
71 int alrm_hour;
72 int alrm_mday;
73};
74
75static int stk17ta8_rtc_set_time(struct device *dev, struct rtc_time *tm)
76{
77 struct platform_device *pdev = to_platform_device(dev);
78 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
79 void __iomem *ioaddr = pdata->ioaddr;
80 u8 flags;
81
82 flags = readb(pdata->ioaddr + RTC_FLAGS);
83 writeb(flags | RTC_WRITE, pdata->ioaddr + RTC_FLAGS);
84
85 writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR);
86 writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH);
87 writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
88 writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE);
89 writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS);
90 writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES);
91 writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
92 writeb(bin2bcd((tm->tm_year + 1900) / 100), ioaddr + RTC_CENTURY);
93
94 writeb(flags & ~RTC_WRITE, pdata->ioaddr + RTC_FLAGS);
95 return 0;
96}
97
98static int stk17ta8_rtc_read_time(struct device *dev, struct rtc_time *tm)
99{
100 struct platform_device *pdev = to_platform_device(dev);
101 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
102 void __iomem *ioaddr = pdata->ioaddr;
103 unsigned int year, month, day, hour, minute, second, week;
104 unsigned int century;
105 u8 flags;
106
107
108 if (pdata->last_jiffies == jiffies)
109 msleep(1);
110 pdata->last_jiffies = jiffies;
111
112 flags = readb(pdata->ioaddr + RTC_FLAGS);
113 writeb(flags | RTC_READ, ioaddr + RTC_FLAGS);
114 second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
115 minute = readb(ioaddr + RTC_MINUTES);
116 hour = readb(ioaddr + RTC_HOURS);
117 day = readb(ioaddr + RTC_DATE);
118 week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
119 month = readb(ioaddr + RTC_MONTH);
120 year = readb(ioaddr + RTC_YEAR);
121 century = readb(ioaddr + RTC_CENTURY);
122 writeb(flags & ~RTC_READ, ioaddr + RTC_FLAGS);
123 tm->tm_sec = bcd2bin(second);
124 tm->tm_min = bcd2bin(minute);
125 tm->tm_hour = bcd2bin(hour);
126 tm->tm_mday = bcd2bin(day);
127 tm->tm_wday = bcd2bin(week);
128 tm->tm_mon = bcd2bin(month) - 1;
129
130 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
131
132 if (rtc_valid_tm(tm) < 0) {
133 dev_err(dev, "retrieved date/time is not valid.\n");
134 rtc_time_to_tm(0, tm);
135 }
136 return 0;
137}
138
139static void stk17ta8_rtc_update_alarm(struct rtc_plat_data *pdata)
140{
141 void __iomem *ioaddr = pdata->ioaddr;
142 unsigned long irqflags;
143 u8 flags;
144
145 spin_lock_irqsave(&pdata->rtc->irq_lock, irqflags);
146
147 flags = readb(ioaddr + RTC_FLAGS);
148 writeb(flags | RTC_WRITE, ioaddr + RTC_FLAGS);
149
150 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
151 0x80 : bin2bcd(pdata->alrm_mday),
152 ioaddr + RTC_DATE_ALARM);
153 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
154 0x80 : bin2bcd(pdata->alrm_hour),
155 ioaddr + RTC_HOURS_ALARM);
156 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
157 0x80 : bin2bcd(pdata->alrm_min),
158 ioaddr + RTC_MINUTES_ALARM);
159 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
160 0x80 : bin2bcd(pdata->alrm_sec),
161 ioaddr + RTC_SECONDS_ALARM);
162 writeb(pdata->irqen ? RTC_INTS_AIE : 0, ioaddr + RTC_INTERRUPTS);
163 readb(ioaddr + RTC_FLAGS);
164 writeb(flags & ~RTC_WRITE, ioaddr + RTC_FLAGS);
165 spin_unlock_irqrestore(&pdata->rtc->irq_lock, irqflags);
166}
167
168static int stk17ta8_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
169{
170 struct platform_device *pdev = to_platform_device(dev);
171 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
172
173 if (pdata->irq <= 0)
174 return -EINVAL;
175 pdata->alrm_mday = alrm->time.tm_mday;
176 pdata->alrm_hour = alrm->time.tm_hour;
177 pdata->alrm_min = alrm->time.tm_min;
178 pdata->alrm_sec = alrm->time.tm_sec;
179 if (alrm->enabled)
180 pdata->irqen |= RTC_AF;
181 stk17ta8_rtc_update_alarm(pdata);
182 return 0;
183}
184
185static int stk17ta8_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
186{
187 struct platform_device *pdev = to_platform_device(dev);
188 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
189
190 if (pdata->irq <= 0)
191 return -EINVAL;
192 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
193 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
194 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
195 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
196 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
197 return 0;
198}
199
200static irqreturn_t stk17ta8_rtc_interrupt(int irq, void *dev_id)
201{
202 struct platform_device *pdev = dev_id;
203 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
204 void __iomem *ioaddr = pdata->ioaddr;
205 unsigned long events = RTC_IRQF;
206
207
208 if (!(readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_AF))
209 return IRQ_NONE;
210 if (readb(ioaddr + RTC_SECONDS_ALARM) & 0x80)
211 events |= RTC_UF;
212 else
213 events |= RTC_AF;
214 rtc_update_irq(pdata->rtc, 1, events);
215 return IRQ_HANDLED;
216}
217
218static int stk17ta8_rtc_ioctl(struct device *dev, unsigned int cmd,
219 unsigned long arg)
220{
221 struct platform_device *pdev = to_platform_device(dev);
222 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
223
224 if (pdata->irq <= 0)
225 return -ENOIOCTLCMD;
226 switch (cmd) {
227 case RTC_AIE_OFF:
228 pdata->irqen &= ~RTC_AF;
229 stk17ta8_rtc_update_alarm(pdata);
230 break;
231 case RTC_AIE_ON:
232 pdata->irqen |= RTC_AF;
233 stk17ta8_rtc_update_alarm(pdata);
234 break;
235 default:
236 return -ENOIOCTLCMD;
237 }
238 return 0;
239}
240
241static const struct rtc_class_ops stk17ta8_rtc_ops = {
242 .read_time = stk17ta8_rtc_read_time,
243 .set_time = stk17ta8_rtc_set_time,
244 .read_alarm = stk17ta8_rtc_read_alarm,
245 .set_alarm = stk17ta8_rtc_set_alarm,
246 .ioctl = stk17ta8_rtc_ioctl,
247};
248
249static ssize_t stk17ta8_nvram_read(struct kobject *kobj,
250 struct bin_attribute *attr, char *buf,
251 loff_t pos, size_t size)
252{
253 struct platform_device *pdev =
254 to_platform_device(container_of(kobj, struct device, kobj));
255 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
256 void __iomem *ioaddr = pdata->ioaddr;
257 ssize_t count;
258
259 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
260 *buf++ = readb(ioaddr + pos++);
261 return count;
262}
263
264static ssize_t stk17ta8_nvram_write(struct kobject *kobj,
265 struct bin_attribute *attr, char *buf,
266 loff_t pos, size_t size)
267{
268 struct platform_device *pdev =
269 to_platform_device(container_of(kobj, struct device, kobj));
270 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
271 void __iomem *ioaddr = pdata->ioaddr;
272 ssize_t count;
273
274 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
275 writeb(*buf++, ioaddr + pos++);
276 return count;
277}
278
279static struct bin_attribute stk17ta8_nvram_attr = {
280 .attr = {
281 .name = "nvram",
282 .mode = S_IRUGO | S_IWUSR,
283 },
284 .size = RTC_OFFSET,
285 .read = stk17ta8_nvram_read,
286 .write = stk17ta8_nvram_write,
287};
288
289static int __init stk17ta8_rtc_probe(struct platform_device *pdev)
290{
291 struct rtc_device *rtc;
292 struct resource *res;
293 unsigned int cal;
294 unsigned int flags;
295 struct rtc_plat_data *pdata;
296 void __iomem *ioaddr = NULL;
297 int ret = 0;
298
299 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
300 if (!res)
301 return -ENODEV;
302
303 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
304 if (!pdata)
305 return -ENOMEM;
306 if (!request_mem_region(res->start, RTC_REG_SIZE, pdev->name)) {
307 ret = -EBUSY;
308 goto out;
309 }
310 pdata->baseaddr = res->start;
311 ioaddr = ioremap(pdata->baseaddr, RTC_REG_SIZE);
312 if (!ioaddr) {
313 ret = -ENOMEM;
314 goto out;
315 }
316 pdata->ioaddr = ioaddr;
317 pdata->irq = platform_get_irq(pdev, 0);
318
319
320 cal = readb(ioaddr + RTC_CALIBRATION);
321 if (cal & RTC_STOP) {
322 cal &= RTC_CAL_MASK;
323 flags = readb(ioaddr + RTC_FLAGS);
324 writeb(flags | RTC_WRITE, ioaddr + RTC_FLAGS);
325 writeb(cal, ioaddr + RTC_CALIBRATION);
326 writeb(flags & ~RTC_WRITE, ioaddr + RTC_FLAGS);
327 }
328 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_PF)
329 dev_warn(&pdev->dev, "voltage-low detected.\n");
330
331 if (pdata->irq > 0) {
332 writeb(0, ioaddr + RTC_INTERRUPTS);
333 if (request_irq(pdata->irq, stk17ta8_rtc_interrupt,
334 IRQF_DISABLED | IRQF_SHARED,
335 pdev->name, pdev) < 0) {
336 dev_warn(&pdev->dev, "interrupt not available.\n");
337 pdata->irq = 0;
338 }
339 }
340
341 rtc = rtc_device_register(pdev->name, &pdev->dev,
342 &stk17ta8_rtc_ops, THIS_MODULE);
343 if (IS_ERR(rtc)) {
344 ret = PTR_ERR(rtc);
345 goto out;
346 }
347 pdata->rtc = rtc;
348 pdata->last_jiffies = jiffies;
349 platform_set_drvdata(pdev, pdata);
350 ret = sysfs_create_bin_file(&pdev->dev.kobj, &stk17ta8_nvram_attr);
351 if (ret)
352 goto out;
353 return 0;
354 out:
355 if (pdata->rtc)
356 rtc_device_unregister(pdata->rtc);
357 if (pdata->irq > 0)
358 free_irq(pdata->irq, pdev);
359 if (ioaddr)
360 iounmap(ioaddr);
361 if (pdata->baseaddr)
362 release_mem_region(pdata->baseaddr, RTC_REG_SIZE);
363 kfree(pdata);
364 return ret;
365}
366
367static int __devexit stk17ta8_rtc_remove(struct platform_device *pdev)
368{
369 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
370
371 sysfs_remove_bin_file(&pdev->dev.kobj, &stk17ta8_nvram_attr);
372 rtc_device_unregister(pdata->rtc);
373 if (pdata->irq > 0) {
374 writeb(0, pdata->ioaddr + RTC_INTERRUPTS);
375 free_irq(pdata->irq, pdev);
376 }
377 iounmap(pdata->ioaddr);
378 release_mem_region(pdata->baseaddr, RTC_REG_SIZE);
379 kfree(pdata);
380 return 0;
381}
382
383
384MODULE_ALIAS("platform:stk17ta8");
385
386static struct platform_driver stk17ta8_rtc_driver = {
387 .probe = stk17ta8_rtc_probe,
388 .remove = __devexit_p(stk17ta8_rtc_remove),
389 .driver = {
390 .name = "stk17ta8",
391 .owner = THIS_MODULE,
392 },
393};
394
395static __init int stk17ta8_init(void)
396{
397 return platform_driver_register(&stk17ta8_rtc_driver);
398}
399
400static __exit void stk17ta8_exit(void)
401{
402 platform_driver_unregister(&stk17ta8_rtc_driver);
403}
404
405module_init(stk17ta8_init);
406module_exit(stk17ta8_exit);
407
408MODULE_AUTHOR("Thomas Hommel <thomas.hommel@gefanuc.com>");
409MODULE_DESCRIPTION("Simtek STK17TA8 RTC driver");
410MODULE_LICENSE("GPL");
411MODULE_VERSION(DRV_VERSION);
412
