xref: /openbmc/linux/drivers/rtc/rtc-pcf50633.c (revision 565d76cb)
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/slab.h>
22 #include <linux/platform_device.h>
23 #include <linux/rtc.h>
24 #include <linux/bcd.h>
25 #include <linux/err.h>
26 
27 #include <linux/mfd/pcf50633/core.h>
28 
29 #define PCF50633_REG_RTCSC	0x59 /* Second */
30 #define PCF50633_REG_RTCMN	0x5a /* Minute */
31 #define PCF50633_REG_RTCHR	0x5b /* Hour */
32 #define PCF50633_REG_RTCWD	0x5c /* Weekday */
33 #define PCF50633_REG_RTCDT	0x5d /* Day */
34 #define PCF50633_REG_RTCMT	0x5e /* Month */
35 #define PCF50633_REG_RTCYR	0x5f /* Year */
36 #define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
37 #define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
38 #define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
39 #define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
40 #define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
41 #define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
42 #define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */
43 
44 enum pcf50633_time_indexes {
45 	PCF50633_TI_SEC,
46 	PCF50633_TI_MIN,
47 	PCF50633_TI_HOUR,
48 	PCF50633_TI_WKDAY,
49 	PCF50633_TI_DAY,
50 	PCF50633_TI_MONTH,
51 	PCF50633_TI_YEAR,
52 	PCF50633_TI_EXTENT /* always last */
53 };
54 
55 struct pcf50633_time {
56 	u_int8_t time[PCF50633_TI_EXTENT];
57 };
58 
59 struct pcf50633_rtc {
60 	int alarm_enabled;
61 	int second_enabled;
62 	int alarm_pending;
63 
64 	struct pcf50633 *pcf;
65 	struct rtc_device *rtc_dev;
66 };
67 
68 static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
69 {
70 	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
71 	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
72 	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
73 	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
74 	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
75 	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
76 	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
77 }
78 
79 static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
80 {
81 	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
82 	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
83 	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
84 	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
85 	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
86 	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
87 	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
88 }
89 
90 static int
91 pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
92 {
93 	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
94 	int err;
95 
96 	if (enabled)
97 		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
98 	else
99 		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
100 
101 	if (err < 0)
102 		return err;
103 
104 	rtc->alarm_enabled = enabled;
105 
106 	return 0;
107 }
108 
109 static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
110 {
111 	struct pcf50633_rtc *rtc;
112 	struct pcf50633_time pcf_tm;
113 	int ret;
114 
115 	rtc = dev_get_drvdata(dev);
116 
117 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
118 					    PCF50633_TI_EXTENT,
119 					    &pcf_tm.time[0]);
120 	if (ret != PCF50633_TI_EXTENT) {
121 		dev_err(dev, "Failed to read time\n");
122 		return -EIO;
123 	}
124 
125 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
126 		pcf_tm.time[PCF50633_TI_DAY],
127 		pcf_tm.time[PCF50633_TI_MONTH],
128 		pcf_tm.time[PCF50633_TI_YEAR],
129 		pcf_tm.time[PCF50633_TI_HOUR],
130 		pcf_tm.time[PCF50633_TI_MIN],
131 		pcf_tm.time[PCF50633_TI_SEC]);
132 
133 	pcf2rtc_time(tm, &pcf_tm);
134 
135 	dev_dbg(dev, "RTC_TIME: %u.%u.%u %u:%u:%u\n",
136 		tm->tm_mday, tm->tm_mon, tm->tm_year,
137 		tm->tm_hour, tm->tm_min, tm->tm_sec);
138 
139 	return rtc_valid_tm(tm);
140 }
141 
142 static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
143 {
144 	struct pcf50633_rtc *rtc;
145 	struct pcf50633_time pcf_tm;
146 	int second_masked, alarm_masked, ret = 0;
147 
148 	rtc = dev_get_drvdata(dev);
149 
150 	dev_dbg(dev, "RTC_TIME: %u.%u.%u %u:%u:%u\n",
151 		tm->tm_mday, tm->tm_mon, tm->tm_year,
152 		tm->tm_hour, tm->tm_min, tm->tm_sec);
153 
154 	rtc2pcf_time(&pcf_tm, tm);
155 
156 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
157 		pcf_tm.time[PCF50633_TI_DAY],
158 		pcf_tm.time[PCF50633_TI_MONTH],
159 		pcf_tm.time[PCF50633_TI_YEAR],
160 		pcf_tm.time[PCF50633_TI_HOUR],
161 		pcf_tm.time[PCF50633_TI_MIN],
162 		pcf_tm.time[PCF50633_TI_SEC]);
163 
164 
165 	second_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_SECOND);
166 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
167 
168 	if (!second_masked)
169 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_SECOND);
170 	if (!alarm_masked)
171 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
172 
173 	/* Returns 0 on success */
174 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
175 					     PCF50633_TI_EXTENT,
176 					     &pcf_tm.time[0]);
177 
178 	if (!second_masked)
179 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_SECOND);
180 	if (!alarm_masked)
181 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
182 
183 	return ret;
184 }
185 
186 static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
187 {
188 	struct pcf50633_rtc *rtc;
189 	struct pcf50633_time pcf_tm;
190 	int ret = 0;
191 
192 	rtc = dev_get_drvdata(dev);
193 
194 	alrm->enabled = rtc->alarm_enabled;
195 	alrm->pending = rtc->alarm_pending;
196 
197 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
198 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
199 	if (ret != PCF50633_TI_EXTENT) {
200 		dev_err(dev, "Failed to read time\n");
201 		return -EIO;
202 	}
203 
204 	pcf2rtc_time(&alrm->time, &pcf_tm);
205 
206 	return rtc_valid_tm(&alrm->time);
207 }
208 
209 static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
210 {
211 	struct pcf50633_rtc *rtc;
212 	struct pcf50633_time pcf_tm;
213 	int alarm_masked, ret = 0;
214 
215 	rtc = dev_get_drvdata(dev);
216 
217 	rtc2pcf_time(&pcf_tm, &alrm->time);
218 
219 	/* do like mktime does and ignore tm_wday */
220 	pcf_tm.time[PCF50633_TI_WKDAY] = 7;
221 
222 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
223 
224 	/* disable alarm interrupt */
225 	if (!alarm_masked)
226 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
227 
228 	/* Returns 0 on success */
229 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
230 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
231 	if (!alrm->enabled)
232 		rtc->alarm_pending = 0;
233 
234 	if (!alarm_masked || alrm->enabled)
235 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
236 	rtc->alarm_enabled = alrm->enabled;
237 
238 	return ret;
239 }
240 
241 static struct rtc_class_ops pcf50633_rtc_ops = {
242 	.read_time		= pcf50633_rtc_read_time,
243 	.set_time		= pcf50633_rtc_set_time,
244 	.read_alarm		= pcf50633_rtc_read_alarm,
245 	.set_alarm		= pcf50633_rtc_set_alarm,
246 	.alarm_irq_enable	= pcf50633_rtc_alarm_irq_enable,
247 };
248 
249 static void pcf50633_rtc_irq(int irq, void *data)
250 {
251 	struct pcf50633_rtc *rtc = data;
252 
253 	switch (irq) {
254 	case PCF50633_IRQ_ALARM:
255 		rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
256 		rtc->alarm_pending = 1;
257 		break;
258 	case PCF50633_IRQ_SECOND:
259 		rtc_update_irq(rtc->rtc_dev, 1, RTC_UF | RTC_IRQF);
260 		break;
261 	}
262 }
263 
264 static int __devinit pcf50633_rtc_probe(struct platform_device *pdev)
265 {
266 	struct pcf50633_rtc *rtc;
267 
268 	rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
269 	if (!rtc)
270 		return -ENOMEM;
271 
272 	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
273 	platform_set_drvdata(pdev, rtc);
274 	rtc->rtc_dev = rtc_device_register("pcf50633-rtc", &pdev->dev,
275 				&pcf50633_rtc_ops, THIS_MODULE);
276 
277 	if (IS_ERR(rtc->rtc_dev)) {
278 		int ret =  PTR_ERR(rtc->rtc_dev);
279 		kfree(rtc);
280 		return ret;
281 	}
282 
283 	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
284 					pcf50633_rtc_irq, rtc);
285 	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_SECOND,
286 					pcf50633_rtc_irq, rtc);
287 
288 	return 0;
289 }
290 
291 static int __devexit pcf50633_rtc_remove(struct platform_device *pdev)
292 {
293 	struct pcf50633_rtc *rtc;
294 
295 	rtc = platform_get_drvdata(pdev);
296 
297 	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);
298 	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_SECOND);
299 
300 	rtc_device_unregister(rtc->rtc_dev);
301 	kfree(rtc);
302 
303 	return 0;
304 }
305 
306 static struct platform_driver pcf50633_rtc_driver = {
307 	.driver = {
308 		.name = "pcf50633-rtc",
309 	},
310 	.probe = pcf50633_rtc_probe,
311 	.remove = __devexit_p(pcf50633_rtc_remove),
312 };
313 
314 static int __init pcf50633_rtc_init(void)
315 {
316 	return platform_driver_register(&pcf50633_rtc_driver);
317 }
318 module_init(pcf50633_rtc_init);
319 
320 static void __exit pcf50633_rtc_exit(void)
321 {
322 	platform_driver_unregister(&pcf50633_rtc_driver);
323 }
324 module_exit(pcf50633_rtc_exit);
325 
326 MODULE_DESCRIPTION("PCF50633 RTC driver");
327 MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
328 MODULE_LICENSE("GPL");
329 
330