This source file includes following definitions.
- ds1553_rtc_set_time
- ds1553_rtc_read_time
- ds1553_rtc_update_alarm
- ds1553_rtc_set_alarm
- ds1553_rtc_read_alarm
- ds1553_rtc_interrupt
- ds1553_rtc_alarm_irq_enable
- ds1553_nvram_read
- ds1553_nvram_write
- ds1553_rtc_probe
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8 #include <linux/bcd.h>
9 #include <linux/init.h>
10 #include <linux/kernel.h>
11 #include <linux/gfp.h>
12 #include <linux/delay.h>
13 #include <linux/jiffies.h>
14 #include <linux/interrupt.h>
15 #include <linux/rtc.h>
16 #include <linux/platform_device.h>
17 #include <linux/io.h>
18 #include <linux/module.h>
19
20 #define RTC_REG_SIZE 0x2000
21 #define RTC_OFFSET 0x1ff0
22
23 #define RTC_FLAGS (RTC_OFFSET + 0)
24 #define RTC_SECONDS_ALARM (RTC_OFFSET + 2)
25 #define RTC_MINUTES_ALARM (RTC_OFFSET + 3)
26 #define RTC_HOURS_ALARM (RTC_OFFSET + 4)
27 #define RTC_DATE_ALARM (RTC_OFFSET + 5)
28 #define RTC_INTERRUPTS (RTC_OFFSET + 6)
29 #define RTC_WATCHDOG (RTC_OFFSET + 7)
30 #define RTC_CONTROL (RTC_OFFSET + 8)
31 #define RTC_CENTURY (RTC_OFFSET + 8)
32 #define RTC_SECONDS (RTC_OFFSET + 9)
33 #define RTC_MINUTES (RTC_OFFSET + 10)
34 #define RTC_HOURS (RTC_OFFSET + 11)
35 #define RTC_DAY (RTC_OFFSET + 12)
36 #define RTC_DATE (RTC_OFFSET + 13)
37 #define RTC_MONTH (RTC_OFFSET + 14)
38 #define RTC_YEAR (RTC_OFFSET + 15)
39
40 #define RTC_CENTURY_MASK 0x3f
41 #define RTC_SECONDS_MASK 0x7f
42 #define RTC_DAY_MASK 0x07
43
44
45 #define RTC_WRITE 0x80
46 #define RTC_READ 0x40
47
48
49 #define RTC_STOP 0x80
50
51
52 #define RTC_FLAGS_AF 0x40
53 #define RTC_FLAGS_BLF 0x10
54
55
56 #define RTC_INTS_AE 0x80
57
58 struct rtc_plat_data {
59 struct rtc_device *rtc;
60 void __iomem *ioaddr;
61 unsigned long last_jiffies;
62 int irq;
63 unsigned int irqen;
64 int alrm_sec;
65 int alrm_min;
66 int alrm_hour;
67 int alrm_mday;
68 spinlock_t lock;
69 };
70
71 static int ds1553_rtc_set_time(struct device *dev, struct rtc_time *tm)
72 {
73 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
74 void __iomem *ioaddr = pdata->ioaddr;
75 u8 century;
76
77 century = bin2bcd((tm->tm_year + 1900) / 100);
78
79 writeb(RTC_WRITE, pdata->ioaddr + RTC_CONTROL);
80
81 writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR);
82 writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH);
83 writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
84 writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE);
85 writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS);
86 writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES);
87 writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
88
89
90 writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
91 writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
92 return 0;
93 }
94
95 static int ds1553_rtc_read_time(struct device *dev, struct rtc_time *tm)
96 {
97 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
98 void __iomem *ioaddr = pdata->ioaddr;
99 unsigned int year, month, day, hour, minute, second, week;
100 unsigned int century;
101
102
103 if (pdata->last_jiffies == jiffies)
104 msleep(1);
105 pdata->last_jiffies = jiffies;
106 writeb(RTC_READ, ioaddr + RTC_CONTROL);
107 second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
108 minute = readb(ioaddr + RTC_MINUTES);
109 hour = readb(ioaddr + RTC_HOURS);
110 day = readb(ioaddr + RTC_DATE);
111 week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
112 month = readb(ioaddr + RTC_MONTH);
113 year = readb(ioaddr + RTC_YEAR);
114 century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
115 writeb(0, ioaddr + RTC_CONTROL);
116 tm->tm_sec = bcd2bin(second);
117 tm->tm_min = bcd2bin(minute);
118 tm->tm_hour = bcd2bin(hour);
119 tm->tm_mday = bcd2bin(day);
120 tm->tm_wday = bcd2bin(week);
121 tm->tm_mon = bcd2bin(month) - 1;
122
123 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
124
125 return 0;
126 }
127
128 static void ds1553_rtc_update_alarm(struct rtc_plat_data *pdata)
129 {
130 void __iomem *ioaddr = pdata->ioaddr;
131 unsigned long flags;
132
133 spin_lock_irqsave(&pdata->lock, flags);
134 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
135 0x80 : bin2bcd(pdata->alrm_mday),
136 ioaddr + RTC_DATE_ALARM);
137 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
138 0x80 : bin2bcd(pdata->alrm_hour),
139 ioaddr + RTC_HOURS_ALARM);
140 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
141 0x80 : bin2bcd(pdata->alrm_min),
142 ioaddr + RTC_MINUTES_ALARM);
143 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
144 0x80 : bin2bcd(pdata->alrm_sec),
145 ioaddr + RTC_SECONDS_ALARM);
146 writeb(pdata->irqen ? RTC_INTS_AE : 0, ioaddr + RTC_INTERRUPTS);
147 readb(ioaddr + RTC_FLAGS);
148 spin_unlock_irqrestore(&pdata->lock, flags);
149 }
150
151 static int ds1553_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
152 {
153 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
154
155 if (pdata->irq <= 0)
156 return -EINVAL;
157 pdata->alrm_mday = alrm->time.tm_mday;
158 pdata->alrm_hour = alrm->time.tm_hour;
159 pdata->alrm_min = alrm->time.tm_min;
160 pdata->alrm_sec = alrm->time.tm_sec;
161 if (alrm->enabled)
162 pdata->irqen |= RTC_AF;
163 ds1553_rtc_update_alarm(pdata);
164 return 0;
165 }
166
167 static int ds1553_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
168 {
169 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
170
171 if (pdata->irq <= 0)
172 return -EINVAL;
173 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
174 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
175 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
176 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
177 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
178 return 0;
179 }
180
181 static irqreturn_t ds1553_rtc_interrupt(int irq, void *dev_id)
182 {
183 struct platform_device *pdev = dev_id;
184 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
185 void __iomem *ioaddr = pdata->ioaddr;
186 unsigned long events = 0;
187
188 spin_lock(&pdata->lock);
189
190 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_AF) {
191 events = RTC_IRQF;
192 if (readb(ioaddr + RTC_SECONDS_ALARM) & 0x80)
193 events |= RTC_UF;
194 else
195 events |= RTC_AF;
196 rtc_update_irq(pdata->rtc, 1, events);
197 }
198 spin_unlock(&pdata->lock);
199 return events ? IRQ_HANDLED : IRQ_NONE;
200 }
201
202 static int ds1553_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
203 {
204 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
205
206 if (pdata->irq <= 0)
207 return -EINVAL;
208 if (enabled)
209 pdata->irqen |= RTC_AF;
210 else
211 pdata->irqen &= ~RTC_AF;
212 ds1553_rtc_update_alarm(pdata);
213 return 0;
214 }
215
216 static const struct rtc_class_ops ds1553_rtc_ops = {
217 .read_time = ds1553_rtc_read_time,
218 .set_time = ds1553_rtc_set_time,
219 .read_alarm = ds1553_rtc_read_alarm,
220 .set_alarm = ds1553_rtc_set_alarm,
221 .alarm_irq_enable = ds1553_rtc_alarm_irq_enable,
222 };
223
224 static int ds1553_nvram_read(void *priv, unsigned int pos, void *val,
225 size_t bytes)
226 {
227 struct platform_device *pdev = priv;
228 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
229 void __iomem *ioaddr = pdata->ioaddr;
230 u8 *buf = val;
231
232 for (; bytes; bytes--)
233 *buf++ = readb(ioaddr + pos++);
234 return 0;
235 }
236
237 static int ds1553_nvram_write(void *priv, unsigned int pos, void *val,
238 size_t bytes)
239 {
240 struct platform_device *pdev = priv;
241 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
242 void __iomem *ioaddr = pdata->ioaddr;
243 u8 *buf = val;
244
245 for (; bytes; bytes--)
246 writeb(*buf++, ioaddr + pos++);
247 return 0;
248 }
249
250 static int ds1553_rtc_probe(struct platform_device *pdev)
251 {
252 struct resource *res;
253 unsigned int cen, sec;
254 struct rtc_plat_data *pdata;
255 void __iomem *ioaddr;
256 int ret = 0;
257 struct nvmem_config nvmem_cfg = {
258 .name = "ds1553_nvram",
259 .word_size = 1,
260 .stride = 1,
261 .size = RTC_OFFSET,
262 .reg_read = ds1553_nvram_read,
263 .reg_write = ds1553_nvram_write,
264 .priv = pdev,
265 };
266
267 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
268 if (!pdata)
269 return -ENOMEM;
270
271 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
272 ioaddr = devm_ioremap_resource(&pdev->dev, res);
273 if (IS_ERR(ioaddr))
274 return PTR_ERR(ioaddr);
275 pdata->ioaddr = ioaddr;
276 pdata->irq = platform_get_irq(pdev, 0);
277
278
279 sec = readb(ioaddr + RTC_SECONDS);
280 if (sec & RTC_STOP) {
281 sec &= RTC_SECONDS_MASK;
282 cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
283 writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
284 writeb(sec, ioaddr + RTC_SECONDS);
285 writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
286 }
287 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_BLF)
288 dev_warn(&pdev->dev, "voltage-low detected.\n");
289
290 spin_lock_init(&pdata->lock);
291 pdata->last_jiffies = jiffies;
292 platform_set_drvdata(pdev, pdata);
293
294 pdata->rtc = devm_rtc_allocate_device(&pdev->dev);
295 if (IS_ERR(pdata->rtc))
296 return PTR_ERR(pdata->rtc);
297
298 pdata->rtc->ops = &ds1553_rtc_ops;
299 pdata->rtc->nvram_old_abi = true;
300
301 ret = rtc_register_device(pdata->rtc);
302 if (ret)
303 return ret;
304
305 if (pdata->irq > 0) {
306 writeb(0, ioaddr + RTC_INTERRUPTS);
307 if (devm_request_irq(&pdev->dev, pdata->irq,
308 ds1553_rtc_interrupt,
309 0, pdev->name, pdev) < 0) {
310 dev_warn(&pdev->dev, "interrupt not available.\n");
311 pdata->irq = 0;
312 }
313 }
314
315 if (rtc_nvmem_register(pdata->rtc, &nvmem_cfg))
316 dev_err(&pdev->dev, "unable to register nvmem\n");
317
318 return 0;
319 }
320
321
322 MODULE_ALIAS("platform:rtc-ds1553");
323
324 static struct platform_driver ds1553_rtc_driver = {
325 .probe = ds1553_rtc_probe,
326 .driver = {
327 .name = "rtc-ds1553",
328 },
329 };
330
331 module_platform_driver(ds1553_rtc_driver);
332
333 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
334 MODULE_DESCRIPTION("Dallas DS1553 RTC driver");
335 MODULE_LICENSE("GPL");