xref: /openbmc/linux/drivers/rtc/rtc-pcf50633.c (revision d25f0ba9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* NXP PCF50633 RTC Driver
3  *
4  * (C) 2006-2008 by Openmoko, Inc.
5  * Author: Balaji Rao <balajirrao@openmoko.org>
6  * All rights reserved.
7  *
8  * Broken down from monstrous PCF50633 driver mainly by
9  * Harald Welte, Andy Green and Werner Almesberger
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/device.h>
16 #include <linux/slab.h>
17 #include <linux/platform_device.h>
18 #include <linux/rtc.h>
19 #include <linux/bcd.h>
20 #include <linux/err.h>
21 
22 #include <linux/mfd/pcf50633/core.h>
23 
24 #define PCF50633_REG_RTCSC	0x59 /* Second */
25 #define PCF50633_REG_RTCMN	0x5a /* Minute */
26 #define PCF50633_REG_RTCHR	0x5b /* Hour */
27 #define PCF50633_REG_RTCWD	0x5c /* Weekday */
28 #define PCF50633_REG_RTCDT	0x5d /* Day */
29 #define PCF50633_REG_RTCMT	0x5e /* Month */
30 #define PCF50633_REG_RTCYR	0x5f /* Year */
31 #define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
32 #define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
33 #define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
34 #define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
35 #define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
36 #define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
37 #define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */
38 
39 enum pcf50633_time_indexes {
40 	PCF50633_TI_SEC,
41 	PCF50633_TI_MIN,
42 	PCF50633_TI_HOUR,
43 	PCF50633_TI_WKDAY,
44 	PCF50633_TI_DAY,
45 	PCF50633_TI_MONTH,
46 	PCF50633_TI_YEAR,
47 	PCF50633_TI_EXTENT /* always last */
48 };
49 
50 struct pcf50633_time {
51 	u_int8_t time[PCF50633_TI_EXTENT];
52 };
53 
54 struct pcf50633_rtc {
55 	int alarm_enabled;
56 	int alarm_pending;
57 
58 	struct pcf50633 *pcf;
59 	struct rtc_device *rtc_dev;
60 };
61 
pcf2rtc_time(struct rtc_time * rtc,struct pcf50633_time * pcf)62 static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
63 {
64 	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
65 	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
66 	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
67 	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
68 	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
69 	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
70 	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
71 }
72 
rtc2pcf_time(struct pcf50633_time * pcf,struct rtc_time * rtc)73 static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
74 {
75 	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
76 	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
77 	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
78 	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
79 	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
80 	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
81 	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
82 }
83 
84 static int
pcf50633_rtc_alarm_irq_enable(struct device * dev,unsigned int enabled)85 pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
86 {
87 	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
88 	int err;
89 
90 	if (enabled)
91 		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
92 	else
93 		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
94 
95 	if (err < 0)
96 		return err;
97 
98 	rtc->alarm_enabled = enabled;
99 
100 	return 0;
101 }
102 
pcf50633_rtc_read_time(struct device * dev,struct rtc_time * tm)103 static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
104 {
105 	struct pcf50633_rtc *rtc;
106 	struct pcf50633_time pcf_tm;
107 	int ret;
108 
109 	rtc = dev_get_drvdata(dev);
110 
111 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
112 					    PCF50633_TI_EXTENT,
113 					    &pcf_tm.time[0]);
114 	if (ret != PCF50633_TI_EXTENT) {
115 		dev_err(dev, "Failed to read time\n");
116 		return -EIO;
117 	}
118 
119 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
120 		pcf_tm.time[PCF50633_TI_DAY],
121 		pcf_tm.time[PCF50633_TI_MONTH],
122 		pcf_tm.time[PCF50633_TI_YEAR],
123 		pcf_tm.time[PCF50633_TI_HOUR],
124 		pcf_tm.time[PCF50633_TI_MIN],
125 		pcf_tm.time[PCF50633_TI_SEC]);
126 
127 	pcf2rtc_time(tm, &pcf_tm);
128 
129 	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
130 
131 	return 0;
132 }
133 
pcf50633_rtc_set_time(struct device * dev,struct rtc_time * tm)134 static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
135 {
136 	struct pcf50633_rtc *rtc;
137 	struct pcf50633_time pcf_tm;
138 	int alarm_masked, ret = 0;
139 
140 	rtc = dev_get_drvdata(dev);
141 
142 	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
143 
144 	rtc2pcf_time(&pcf_tm, tm);
145 
146 	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
147 		pcf_tm.time[PCF50633_TI_DAY],
148 		pcf_tm.time[PCF50633_TI_MONTH],
149 		pcf_tm.time[PCF50633_TI_YEAR],
150 		pcf_tm.time[PCF50633_TI_HOUR],
151 		pcf_tm.time[PCF50633_TI_MIN],
152 		pcf_tm.time[PCF50633_TI_SEC]);
153 
154 
155 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
156 
157 	if (!alarm_masked)
158 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
159 
160 	/* Returns 0 on success */
161 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
162 					     PCF50633_TI_EXTENT,
163 					     &pcf_tm.time[0]);
164 
165 	if (!alarm_masked)
166 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
167 
168 	return ret;
169 }
170 
pcf50633_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alrm)171 static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
172 {
173 	struct pcf50633_rtc *rtc;
174 	struct pcf50633_time pcf_tm;
175 	int ret = 0;
176 
177 	rtc = dev_get_drvdata(dev);
178 
179 	alrm->enabled = rtc->alarm_enabled;
180 	alrm->pending = rtc->alarm_pending;
181 
182 	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
183 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
184 	if (ret != PCF50633_TI_EXTENT) {
185 		dev_err(dev, "Failed to read time\n");
186 		return -EIO;
187 	}
188 
189 	pcf2rtc_time(&alrm->time, &pcf_tm);
190 
191 	return rtc_valid_tm(&alrm->time);
192 }
193 
pcf50633_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)194 static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
195 {
196 	struct pcf50633_rtc *rtc;
197 	struct pcf50633_time pcf_tm;
198 	int alarm_masked, ret = 0;
199 
200 	rtc = dev_get_drvdata(dev);
201 
202 	rtc2pcf_time(&pcf_tm, &alrm->time);
203 
204 	/* do like mktime does and ignore tm_wday */
205 	pcf_tm.time[PCF50633_TI_WKDAY] = 7;
206 
207 	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
208 
209 	/* disable alarm interrupt */
210 	if (!alarm_masked)
211 		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
212 
213 	/* Returns 0 on success */
214 	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
215 				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
216 	if (!alrm->enabled)
217 		rtc->alarm_pending = 0;
218 
219 	if (!alarm_masked || alrm->enabled)
220 		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
221 	rtc->alarm_enabled = alrm->enabled;
222 
223 	return ret;
224 }
225 
226 static const struct rtc_class_ops pcf50633_rtc_ops = {
227 	.read_time		= pcf50633_rtc_read_time,
228 	.set_time		= pcf50633_rtc_set_time,
229 	.read_alarm		= pcf50633_rtc_read_alarm,
230 	.set_alarm		= pcf50633_rtc_set_alarm,
231 	.alarm_irq_enable	= pcf50633_rtc_alarm_irq_enable,
232 };
233 
pcf50633_rtc_irq(int irq,void * data)234 static void pcf50633_rtc_irq(int irq, void *data)
235 {
236 	struct pcf50633_rtc *rtc = data;
237 
238 	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
239 	rtc->alarm_pending = 1;
240 }
241 
pcf50633_rtc_probe(struct platform_device * pdev)242 static int pcf50633_rtc_probe(struct platform_device *pdev)
243 {
244 	struct pcf50633_rtc *rtc;
245 
246 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
247 	if (!rtc)
248 		return -ENOMEM;
249 
250 	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
251 	platform_set_drvdata(pdev, rtc);
252 	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "pcf50633-rtc",
253 				&pcf50633_rtc_ops, THIS_MODULE);
254 
255 	if (IS_ERR(rtc->rtc_dev))
256 		return PTR_ERR(rtc->rtc_dev);
257 
258 	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
259 					pcf50633_rtc_irq, rtc);
260 	return 0;
261 }
262 
pcf50633_rtc_remove(struct platform_device * pdev)263 static void pcf50633_rtc_remove(struct platform_device *pdev)
264 {
265 	struct pcf50633_rtc *rtc;
266 
267 	rtc = platform_get_drvdata(pdev);
268 	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);
269 }
270 
271 static struct platform_driver pcf50633_rtc_driver = {
272 	.driver = {
273 		.name = "pcf50633-rtc",
274 	},
275 	.probe = pcf50633_rtc_probe,
276 	.remove_new = pcf50633_rtc_remove,
277 };
278 
279 module_platform_driver(pcf50633_rtc_driver);
280 
281 MODULE_DESCRIPTION("PCF50633 RTC driver");
282 MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
283 MODULE_LICENSE("GPL");
284 
285