xref: /linux/drivers/rtc/rtc-da9052.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
1 /*
2  * Real time clock driver for DA9052
3  *
4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
5  *
6  * Author: Dajun Dajun Chen <dajun.chen@diasemi.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  */
14 
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/rtc.h>
18 #include <linux/err.h>
19 
20 #include <linux/mfd/da9052/da9052.h>
21 #include <linux/mfd/da9052/reg.h>
22 
23 #define rtc_err(rtc, fmt, ...) \
24 		dev_err(rtc->da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)
25 
26 struct da9052_rtc {
27 	struct rtc_device *rtc;
28 	struct da9052 *da9052;
29 };
30 
31 static int da9052_rtc_enable_alarm(struct da9052_rtc *rtc, bool enable)
32 {
33 	int ret;
34 	if (enable) {
35 		ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
36 				DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON,
37 				DA9052_ALARM_Y_ALARM_ON);
38 		if (ret != 0)
39 			rtc_err(rtc, "Failed to enable ALM: %d\n", ret);
40 	} else {
41 		ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
42 			DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, 0);
43 		if (ret != 0)
44 			rtc_err(rtc, "Write error: %d\n", ret);
45 	}
46 	return ret;
47 }
48 
49 static irqreturn_t da9052_rtc_irq(int irq, void *data)
50 {
51 	struct da9052_rtc *rtc = data;
52 
53 	rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
54 
55 	return IRQ_HANDLED;
56 }
57 
58 static int da9052_read_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
59 {
60 	int ret;
61 	uint8_t v[5];
62 
63 	ret = da9052_group_read(rtc->da9052, DA9052_ALARM_MI_REG, 5, v);
64 	if (ret != 0) {
65 		rtc_err(rtc, "Failed to group read ALM: %d\n", ret);
66 		return ret;
67 	}
68 
69 	rtc_tm->tm_year = (v[4] & DA9052_RTC_YEAR) + 100;
70 	rtc_tm->tm_mon  = (v[3] & DA9052_RTC_MONTH) - 1;
71 	rtc_tm->tm_mday = v[2] & DA9052_RTC_DAY;
72 	rtc_tm->tm_hour = v[1] & DA9052_RTC_HOUR;
73 	rtc_tm->tm_min  = v[0] & DA9052_RTC_MIN;
74 
75 	ret = rtc_valid_tm(rtc_tm);
76 	return ret;
77 }
78 
79 static int da9052_set_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)
80 {
81 	struct da9052 *da9052 = rtc->da9052;
82 	unsigned long alm_time;
83 	int ret;
84 	uint8_t v[3];
85 
86 	ret = rtc_tm_to_time(rtc_tm, &alm_time);
87 	if (ret != 0)
88 		return ret;
89 
90 	if (rtc_tm->tm_sec > 0) {
91 		alm_time += 60 - rtc_tm->tm_sec;
92 		rtc_time_to_tm(alm_time, rtc_tm);
93 	}
94 	BUG_ON(rtc_tm->tm_sec); /* it will cause repeated irqs if not zero */
95 
96 	rtc_tm->tm_year -= 100;
97 	rtc_tm->tm_mon += 1;
98 
99 	ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,
100 				DA9052_RTC_MIN, rtc_tm->tm_min);
101 	if (ret != 0) {
102 		rtc_err(rtc, "Failed to write ALRM MIN: %d\n", ret);
103 		return ret;
104 	}
105 
106 	v[0] = rtc_tm->tm_hour;
107 	v[1] = rtc_tm->tm_mday;
108 	v[2] = rtc_tm->tm_mon;
109 
110 	ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);
111 	if (ret < 0)
112 		return ret;
113 
114 	ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,
115 				DA9052_RTC_YEAR, rtc_tm->tm_year);
116 	if (ret != 0)
117 		rtc_err(rtc, "Failed to write ALRM YEAR: %d\n", ret);
118 
119 	return ret;
120 }
121 
122 static int da9052_rtc_get_alarm_status(struct da9052_rtc *rtc)
123 {
124 	int ret;
125 
126 	ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_Y_REG);
127 	if (ret < 0) {
128 		rtc_err(rtc, "Failed to read ALM: %d\n", ret);
129 		return ret;
130 	}
131 
132 	return !!(ret&DA9052_ALARM_Y_ALARM_ON);
133 }
134 
135 static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
136 {
137 	struct da9052_rtc *rtc = dev_get_drvdata(dev);
138 	uint8_t v[6];
139 	int ret;
140 
141 	ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
142 	if (ret < 0) {
143 		rtc_err(rtc, "Failed to read RTC time : %d\n", ret);
144 		return ret;
145 	}
146 
147 	rtc_tm->tm_year = (v[5] & DA9052_RTC_YEAR) + 100;
148 	rtc_tm->tm_mon  = (v[4] & DA9052_RTC_MONTH) - 1;
149 	rtc_tm->tm_mday = v[3] & DA9052_RTC_DAY;
150 	rtc_tm->tm_hour = v[2] & DA9052_RTC_HOUR;
151 	rtc_tm->tm_min  = v[1] & DA9052_RTC_MIN;
152 	rtc_tm->tm_sec  = v[0] & DA9052_RTC_SEC;
153 
154 	ret = rtc_valid_tm(rtc_tm);
155 	return ret;
156 }
157 
158 static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)
159 {
160 	struct da9052_rtc *rtc;
161 	uint8_t v[6];
162 	int ret;
163 
164 	rtc = dev_get_drvdata(dev);
165 
166 	v[0] = tm->tm_sec;
167 	v[1] = tm->tm_min;
168 	v[2] = tm->tm_hour;
169 	v[3] = tm->tm_mday;
170 	v[4] = tm->tm_mon + 1;
171 	v[5] = tm->tm_year - 100;
172 
173 	ret = da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);
174 	if (ret < 0)
175 		rtc_err(rtc, "failed to set RTC time: %d\n", ret);
176 	return ret;
177 }
178 
179 static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
180 {
181 	int ret;
182 	struct rtc_time *tm = &alrm->time;
183 	struct da9052_rtc *rtc = dev_get_drvdata(dev);
184 
185 	ret = da9052_read_alarm(rtc, tm);
186 	if (ret < 0) {
187 		rtc_err(rtc, "failed to read RTC alarm: %d\n", ret);
188 		return ret;
189 	}
190 
191 	alrm->enabled = da9052_rtc_get_alarm_status(rtc);
192 	return 0;
193 }
194 
195 static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
196 {
197 	int ret;
198 	struct rtc_time *tm = &alrm->time;
199 	struct da9052_rtc *rtc = dev_get_drvdata(dev);
200 
201 	ret = da9052_rtc_enable_alarm(rtc, 0);
202 	if (ret < 0)
203 		return ret;
204 
205 	ret = da9052_set_alarm(rtc, tm);
206 	if (ret < 0)
207 		return ret;
208 
209 	ret = da9052_rtc_enable_alarm(rtc, 1);
210 	return ret;
211 }
212 
213 static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
214 {
215 	struct da9052_rtc *rtc = dev_get_drvdata(dev);
216 
217 	return da9052_rtc_enable_alarm(rtc, enabled);
218 }
219 
220 static const struct rtc_class_ops da9052_rtc_ops = {
221 	.read_time	= da9052_rtc_read_time,
222 	.set_time	= da9052_rtc_set_time,
223 	.read_alarm	= da9052_rtc_read_alarm,
224 	.set_alarm	= da9052_rtc_set_alarm,
225 	.alarm_irq_enable = da9052_rtc_alarm_irq_enable,
226 };
227 
228 static int da9052_rtc_probe(struct platform_device *pdev)
229 {
230 	struct da9052_rtc *rtc;
231 	int ret;
232 
233 	rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);
234 	if (!rtc)
235 		return -ENOMEM;
236 
237 	rtc->da9052 = dev_get_drvdata(pdev->dev.parent);
238 	platform_set_drvdata(pdev, rtc);
239 
240 	ret = da9052_reg_write(rtc->da9052, DA9052_BBAT_CONT_REG, 0xFE);
241 	if (ret < 0) {
242 		rtc_err(rtc,
243 			"Failed to setup RTC battery charging: %d\n", ret);
244 		return ret;
245 	}
246 
247 	ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,
248 				DA9052_ALARM_Y_TICK_ON, 0);
249 	if (ret != 0)
250 		rtc_err(rtc, "Failed to disable TICKS: %d\n", ret);
251 
252 	ret = da9052_request_irq(rtc->da9052, DA9052_IRQ_ALARM, "ALM",
253 				da9052_rtc_irq, rtc);
254 	if (ret != 0) {
255 		rtc_err(rtc, "irq registration failed: %d\n", ret);
256 		return ret;
257 	}
258 
259 	rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
260 				       &da9052_rtc_ops, THIS_MODULE);
261 	return PTR_ERR_OR_ZERO(rtc->rtc);
262 }
263 
264 static struct platform_driver da9052_rtc_driver = {
265 	.probe	= da9052_rtc_probe,
266 	.driver = {
267 		.name	= "da9052-rtc",
268 	},
269 };
270 
271 module_platform_driver(da9052_rtc_driver);
272 
273 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");
274 MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");
275 MODULE_LICENSE("GPL");
276 MODULE_ALIAS("platform:da9052-rtc");
277