xref: /openbmc/linux/drivers/rtc/rtc-pcf50633.c (revision 7dd65feb)
1 /* NXP PCF50633 RTC Driver
2  *
3  * (C) 2006-2008 by Openmoko, Inc.
4  * Author: Balaji Rao <balajirrao@openmoko.org>
5  * All rights reserved.
6  *
7  * Broken down from monstrous PCF50633 driver mainly by
8  * Harald Welte, Andy Green and Werner Almesberger
9  *
10  *  This program is free software; you can redistribute  it and/or modify it
11  *  under  the terms of  the GNU General  Public License as published by the
12  *  Free Software Foundation;  either version 2 of the  License, or (at your
13  *  option) any later version.
14  *
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/device.h>
21 #include <linux/platform_device.h>
22 #include <linux/rtc.h>
23 #include <linux/bcd.h>
24 #include <linux/err.h>
25 
26 #include <linux/mfd/pcf50633/core.h>
27 
28 #define PCF50633_REG_RTCSC	0x59 /* Second */
29 #define PCF50633_REG_RTCMN	0x5a /* Minute */
30 #define PCF50633_REG_RTCHR	0x5b /* Hour */
31 #define PCF50633_REG_RTCWD	0x5c /* Weekday */
32 #define PCF50633_REG_RTCDT	0x5d /* Day */
33 #define PCF50633_REG_RTCMT	0x5e /* Month */
34 #define PCF50633_REG_RTCYR	0x5f /* Year */
35 #define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
36 #define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
37 #define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
38 #define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
39 #define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
40 #define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
41 #define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */
42 
43 enum pcf50633_time_indexes {
44 	PCF50633_TI_SEC,
45 	PCF50633_TI_MIN,
46 	PCF50633_TI_HOUR,
47 	PCF50633_TI_WKDAY,
48 	PCF50633_TI_DAY,
49 	PCF50633_TI_MONTH,
50 	PCF50633_TI_YEAR,
51 	PCF50633_TI_EXTENT /* always last */
52 };
53 
54 struct pcf50633_time {
55 	u_int8_t time[PCF50633_TI_EXTENT];
56 };
57 
58 struct pcf50633_rtc {
59 	int alarm_enabled;
60 	int second_enabled;
61 	int alarm_pending;
62 
63 	struct pcf50633 *pcf;
64 	struct rtc_device *rtc_dev;
65 };
66 
67 static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
68 {
69 	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
70 	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
71 	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
72 	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
73 	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
74 	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
75 	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
76 }
77 
78 static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
79 {
80 	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
81 	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
82 	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
83 	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
84 	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
85 	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
86 	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
87 }
88 
89 static int
90 pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
91 {
92 	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
93 	int err;
94 
95 	if (enabled)
96 		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
97 	else
98 		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
99 
100 	if (err < 0)
101 		return err;
102 
103 	rtc->alarm_enabled = enabled;
104 
105 	return 0;
106 }
107 
108 static int
109 pcf50633_rtc_update_irq_enable(struct device *dev, unsigned int enabled)
110 {
111 	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
112 	int err;
113 
114 	if (enabled)
115 		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_SECOND);
116 	else
117 		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_SECOND);
118 
119 	if (err < 0)
120 		return err;
121 
122 	rtc->second_enabled = enabled;
123 
124 	return 0;
125 }
126 
127 static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
128 {
129 	struct pcf50633_rtc *rtc;
130 	struct pcf50633_time pcf_tm;
131 	int ret;
132 
133 	rtc = dev_get_drvdata(dev);
134 
135 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
136 					    PCF50633_TI_EXTENT,
137 					    &pcf_tm.time[0]);
138 	if (ret != PCF50633_TI_EXTENT) {
139 		dev_err(dev, "Failed to read time\n");
140 		return -EIO;
141 	}
142 
143 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
144 		pcf_tm.time[PCF50633_TI_DAY],
145 		pcf_tm.time[PCF50633_TI_MONTH],
146 		pcf_tm.time[PCF50633_TI_YEAR],
147 		pcf_tm.time[PCF50633_TI_HOUR],
148 		pcf_tm.time[PCF50633_TI_MIN],
149 		pcf_tm.time[PCF50633_TI_SEC]);
150 
151 	pcf2rtc_time(tm, &pcf_tm);
152 
153 	dev_dbg(dev, "RTC_TIME: %u.%u.%u %u:%u:%u\n",
154 		tm->tm_mday, tm->tm_mon, tm->tm_year,
155 		tm->tm_hour, tm->tm_min, tm->tm_sec);
156 
157 	return rtc_valid_tm(tm);
158 }
159 
160 static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
161 {
162 	struct pcf50633_rtc *rtc;
163 	struct pcf50633_time pcf_tm;
164 	int second_masked, alarm_masked, ret = 0;
165 
166 	rtc = dev_get_drvdata(dev);
167 
168 	dev_dbg(dev, "RTC_TIME: %u.%u.%u %u:%u:%u\n",
169 		tm->tm_mday, tm->tm_mon, tm->tm_year,
170 		tm->tm_hour, tm->tm_min, tm->tm_sec);
171 
172 	rtc2pcf_time(&pcf_tm, tm);
173 
174 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
175 		pcf_tm.time[PCF50633_TI_DAY],
176 		pcf_tm.time[PCF50633_TI_MONTH],
177 		pcf_tm.time[PCF50633_TI_YEAR],
178 		pcf_tm.time[PCF50633_TI_HOUR],
179 		pcf_tm.time[PCF50633_TI_MIN],
180 		pcf_tm.time[PCF50633_TI_SEC]);
181 
182 
183 	second_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_SECOND);
184 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
185 
186 	if (!second_masked)
187 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_SECOND);
188 	if (!alarm_masked)
189 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
190 
191 	/* Returns 0 on success */
192 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
193 					     PCF50633_TI_EXTENT,
194 					     &pcf_tm.time[0]);
195 
196 	if (!second_masked)
197 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_SECOND);
198 	if (!alarm_masked)
199 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
200 
201 	return ret;
202 }
203 
204 static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
205 {
206 	struct pcf50633_rtc *rtc;
207 	struct pcf50633_time pcf_tm;
208 	int ret = 0;
209 
210 	rtc = dev_get_drvdata(dev);
211 
212 	alrm->enabled = rtc->alarm_enabled;
213 	alrm->pending = rtc->alarm_pending;
214 
215 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
216 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
217 	if (ret != PCF50633_TI_EXTENT) {
218 		dev_err(dev, "Failed to read time\n");
219 		return -EIO;
220 	}
221 
222 	pcf2rtc_time(&alrm->time, &pcf_tm);
223 
224 	return rtc_valid_tm(&alrm->time);
225 }
226 
227 static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
228 {
229 	struct pcf50633_rtc *rtc;
230 	struct pcf50633_time pcf_tm;
231 	int alarm_masked, ret = 0;
232 
233 	rtc = dev_get_drvdata(dev);
234 
235 	rtc2pcf_time(&pcf_tm, &alrm->time);
236 
237 	/* do like mktime does and ignore tm_wday */
238 	pcf_tm.time[PCF50633_TI_WKDAY] = 7;
239 
240 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
241 
242 	/* disable alarm interrupt */
243 	if (!alarm_masked)
244 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
245 
246 	/* Returns 0 on success */
247 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
248 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
249 	if (!alrm->enabled)
250 		rtc->alarm_pending = 0;
251 
252 	if (!alarm_masked || alrm->enabled)
253 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
254 	rtc->alarm_enabled = alrm->enabled;
255 
256 	return ret;
257 }
258 
259 static struct rtc_class_ops pcf50633_rtc_ops = {
260 	.read_time		= pcf50633_rtc_read_time,
261 	.set_time		= pcf50633_rtc_set_time,
262 	.read_alarm		= pcf50633_rtc_read_alarm,
263 	.set_alarm		= pcf50633_rtc_set_alarm,
264 	.alarm_irq_enable 	= pcf50633_rtc_alarm_irq_enable,
265 	.update_irq_enable 	= pcf50633_rtc_update_irq_enable,
266 };
267 
268 static void pcf50633_rtc_irq(int irq, void *data)
269 {
270 	struct pcf50633_rtc *rtc = data;
271 
272 	switch (irq) {
273 	case PCF50633_IRQ_ALARM:
274 		rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
275 		rtc->alarm_pending = 1;
276 		break;
277 	case PCF50633_IRQ_SECOND:
278 		rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF);
279 		break;
280 	}
281 }
282 
283 static int __devinit pcf50633_rtc_probe(struct platform_device *pdev)
284 {
285 	struct pcf50633_rtc *rtc;
286 
287 	rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
288 	if (!rtc)
289 		return -ENOMEM;
290 
291 	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
292 	platform_set_drvdata(pdev, rtc);
293 	rtc->rtc_dev = rtc_device_register("pcf50633-rtc", &pdev->dev,
294 				&pcf50633_rtc_ops, THIS_MODULE);
295 
296 	if (IS_ERR(rtc->rtc_dev)) {
297 		int ret =  PTR_ERR(rtc->rtc_dev);
298 		kfree(rtc);
299 		return ret;
300 	}
301 
302 	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
303 					pcf50633_rtc_irq, rtc);
304 	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_SECOND,
305 					pcf50633_rtc_irq, rtc);
306 
307 	return 0;
308 }
309 
310 static int __devexit pcf50633_rtc_remove(struct platform_device *pdev)
311 {
312 	struct pcf50633_rtc *rtc;
313 
314 	rtc = platform_get_drvdata(pdev);
315 
316 	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);
317 	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_SECOND);
318 
319 	rtc_device_unregister(rtc->rtc_dev);
320 	kfree(rtc);
321 
322 	return 0;
323 }
324 
325 static struct platform_driver pcf50633_rtc_driver = {
326 	.driver = {
327 		.name = "pcf50633-rtc",
328 	},
329 	.probe = pcf50633_rtc_probe,
330 	.remove = __devexit_p(pcf50633_rtc_remove),
331 };
332 
333 static int __init pcf50633_rtc_init(void)
334 {
335 	return platform_driver_register(&pcf50633_rtc_driver);
336 }
337 module_init(pcf50633_rtc_init);
338 
339 static void __exit pcf50633_rtc_exit(void)
340 {
341 	platform_driver_unregister(&pcf50633_rtc_driver);
342 }
343 module_exit(pcf50633_rtc_exit);
344 
345 MODULE_DESCRIPTION("PCF50633 RTC driver");
346 MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
347 MODULE_LICENSE("GPL");
348 
349