Commit | Line | Data |
---|---|---|
02964115 TH |
1 | /* |
2 | * A RTC driver for the Simtek STK17TA8 | |
3 | * | |
4 | * By Thomas Hommel <thomas.hommel@gefanuc.com> | |
5 | * | |
6 | * Based on the DS1553 driver from | |
7 | * Atsushi Nemoto <anemo@mba.ocn.ne.jp> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
12 | */ | |
13 | ||
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 | /* Bits in the Calibration register */ | |
51 | #define RTC_STOP 0x80 | |
52 | ||
53 | /* Bits in the Flags register */ | |
54 | #define RTC_FLAGS_AF 0x40 | |
55 | #define RTC_FLAGS_PF 0x20 | |
56 | #define RTC_WRITE 0x02 | |
57 | #define RTC_READ 0x01 | |
58 | ||
59 | /* Bits in the Interrupts register */ | |
60 | #define RTC_INTS_AIE 0x40 | |
61 | ||
62 | struct 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 | ||
75 | static 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 | ||
fe20ba70 AB |
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); | |
02964115 TH |
93 | |
94 | writeb(flags & ~RTC_WRITE, pdata->ioaddr + RTC_FLAGS); | |
95 | return 0; | |
96 | } | |
97 | ||
98 | static 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 | /* give enough time to update RTC in case of continuous read */ | |
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); | |
fe20ba70 AB |
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; | |
02964115 | 129 | /* year is 1900 + tm->tm_year */ |
fe20ba70 | 130 | tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900; |
02964115 TH |
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 | ||
139 | static 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) ? | |
fe20ba70 | 151 | 0x80 : bin2bcd(pdata->alrm_mday), |
02964115 TH |
152 | ioaddr + RTC_DATE_ALARM); |
153 | writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ? | |
fe20ba70 | 154 | 0x80 : bin2bcd(pdata->alrm_hour), |
02964115 TH |
155 | ioaddr + RTC_HOURS_ALARM); |
156 | writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ? | |
fe20ba70 | 157 | 0x80 : bin2bcd(pdata->alrm_min), |
02964115 TH |
158 | ioaddr + RTC_MINUTES_ALARM); |
159 | writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ? | |
fe20ba70 | 160 | 0x80 : bin2bcd(pdata->alrm_sec), |
02964115 TH |
161 | ioaddr + RTC_SECONDS_ALARM); |
162 | writeb(pdata->irqen ? RTC_INTS_AIE : 0, ioaddr + RTC_INTERRUPTS); | |
163 | readb(ioaddr + RTC_FLAGS); /* clear interrupts */ | |
164 | writeb(flags & ~RTC_WRITE, ioaddr + RTC_FLAGS); | |
165 | spin_unlock_irqrestore(&pdata->rtc->irq_lock, irqflags); | |
166 | } | |
167 | ||
168 | static 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 | ||
185 | static 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 | ||
200 | static 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 | /* read and clear interrupt */ | |
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 | ||
02964115 TH |
218 | static 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; /* fall back into rtc-dev's emulation */ | |
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 | ||
241 | static 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, | |
02964115 TH |
246 | .ioctl = stk17ta8_rtc_ioctl, |
247 | }; | |
248 | ||
c98dbe59 AV |
249 | static ssize_t stk17ta8_nvram_read(struct kobject *kobj, |
250 | struct bin_attribute *attr, char *buf, | |
02964115 TH |
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 | ||
c98dbe59 AV |
264 | static ssize_t stk17ta8_nvram_write(struct kobject *kobj, |
265 | struct bin_attribute *attr, char *buf, | |
02964115 TH |
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 | ||
279 | static struct bin_attribute stk17ta8_nvram_attr = { | |
280 | .attr = { | |
281 | .name = "nvram", | |
a4b1d50e | 282 | .mode = S_IRUGO | S_IWUSR, |
02964115 TH |
283 | }, |
284 | .size = RTC_OFFSET, | |
285 | .read = stk17ta8_nvram_read, | |
286 | .write = stk17ta8_nvram_write, | |
287 | }; | |
288 | ||
289 | static 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 | pdata->irq = -1; | |
307 | if (!request_mem_region(res->start, RTC_REG_SIZE, pdev->name)) { | |
308 | ret = -EBUSY; | |
309 | goto out; | |
310 | } | |
311 | pdata->baseaddr = res->start; | |
312 | ioaddr = ioremap(pdata->baseaddr, RTC_REG_SIZE); | |
313 | if (!ioaddr) { | |
314 | ret = -ENOMEM; | |
315 | goto out; | |
316 | } | |
317 | pdata->ioaddr = ioaddr; | |
318 | pdata->irq = platform_get_irq(pdev, 0); | |
319 | ||
320 | /* turn RTC on if it was not on */ | |
321 | cal = readb(ioaddr + RTC_CALIBRATION); | |
322 | if (cal & RTC_STOP) { | |
323 | cal &= RTC_CAL_MASK; | |
324 | flags = readb(ioaddr + RTC_FLAGS); | |
325 | writeb(flags | RTC_WRITE, ioaddr + RTC_FLAGS); | |
326 | writeb(cal, ioaddr + RTC_CALIBRATION); | |
327 | writeb(flags & ~RTC_WRITE, ioaddr + RTC_FLAGS); | |
328 | } | |
329 | if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_PF) | |
330 | dev_warn(&pdev->dev, "voltage-low detected.\n"); | |
331 | ||
332 | if (pdata->irq >= 0) { | |
333 | writeb(0, ioaddr + RTC_INTERRUPTS); | |
334 | if (request_irq(pdata->irq, stk17ta8_rtc_interrupt, | |
335 | IRQF_DISABLED | IRQF_SHARED, | |
336 | pdev->name, pdev) < 0) { | |
337 | dev_warn(&pdev->dev, "interrupt not available.\n"); | |
338 | pdata->irq = -1; | |
339 | } | |
340 | } | |
341 | ||
342 | rtc = rtc_device_register(pdev->name, &pdev->dev, | |
343 | &stk17ta8_rtc_ops, THIS_MODULE); | |
344 | if (IS_ERR(rtc)) { | |
345 | ret = PTR_ERR(rtc); | |
346 | goto out; | |
347 | } | |
348 | pdata->rtc = rtc; | |
349 | pdata->last_jiffies = jiffies; | |
350 | platform_set_drvdata(pdev, pdata); | |
351 | ret = sysfs_create_bin_file(&pdev->dev.kobj, &stk17ta8_nvram_attr); | |
352 | if (ret) | |
353 | goto out; | |
354 | return 0; | |
355 | out: | |
356 | if (pdata->rtc) | |
357 | rtc_device_unregister(pdata->rtc); | |
358 | if (pdata->irq >= 0) | |
359 | free_irq(pdata->irq, pdev); | |
360 | if (ioaddr) | |
361 | iounmap(ioaddr); | |
362 | if (pdata->baseaddr) | |
363 | release_mem_region(pdata->baseaddr, RTC_REG_SIZE); | |
364 | kfree(pdata); | |
365 | return ret; | |
366 | } | |
367 | ||
368 | static int __devexit stk17ta8_rtc_remove(struct platform_device *pdev) | |
369 | { | |
370 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); | |
371 | ||
372 | sysfs_remove_bin_file(&pdev->dev.kobj, &stk17ta8_nvram_attr); | |
373 | rtc_device_unregister(pdata->rtc); | |
374 | if (pdata->irq >= 0) { | |
375 | writeb(0, pdata->ioaddr + RTC_INTERRUPTS); | |
376 | free_irq(pdata->irq, pdev); | |
377 | } | |
378 | iounmap(pdata->ioaddr); | |
379 | release_mem_region(pdata->baseaddr, RTC_REG_SIZE); | |
380 | kfree(pdata); | |
381 | return 0; | |
382 | } | |
383 | ||
ad28a07b KS |
384 | /* work with hotplug and coldplug */ |
385 | MODULE_ALIAS("platform:stk17ta8"); | |
386 | ||
02964115 TH |
387 | static struct platform_driver stk17ta8_rtc_driver = { |
388 | .probe = stk17ta8_rtc_probe, | |
389 | .remove = __devexit_p(stk17ta8_rtc_remove), | |
390 | .driver = { | |
391 | .name = "stk17ta8", | |
392 | .owner = THIS_MODULE, | |
393 | }, | |
394 | }; | |
395 | ||
396 | static __init int stk17ta8_init(void) | |
397 | { | |
398 | return platform_driver_register(&stk17ta8_rtc_driver); | |
399 | } | |
400 | ||
401 | static __exit void stk17ta8_exit(void) | |
402 | { | |
403 | return platform_driver_unregister(&stk17ta8_rtc_driver); | |
404 | } | |
405 | ||
406 | module_init(stk17ta8_init); | |
407 | module_exit(stk17ta8_exit); | |
408 | ||
409 | MODULE_AUTHOR("Thomas Hommel <thomas.hommel@gefanuc.com>"); | |
410 | MODULE_DESCRIPTION("Simtek STK17TA8 RTC driver"); | |
411 | MODULE_LICENSE("GPL"); | |
412 | MODULE_VERSION(DRV_VERSION); |