19c92ab61SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
2f77fbdf9SAlexey Charkov /*
3f77fbdf9SAlexey Charkov * drivers/rtc/rtc-vt8500.c
4f77fbdf9SAlexey Charkov *
5f77fbdf9SAlexey Charkov * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
6f77fbdf9SAlexey Charkov *
7f77fbdf9SAlexey Charkov * Based on rtc-pxa.c
8f77fbdf9SAlexey Charkov */
9f77fbdf9SAlexey Charkov
10f77fbdf9SAlexey Charkov #include <linux/module.h>
11f77fbdf9SAlexey Charkov #include <linux/rtc.h>
12f77fbdf9SAlexey Charkov #include <linux/init.h>
13f77fbdf9SAlexey Charkov #include <linux/interrupt.h>
14f77fbdf9SAlexey Charkov #include <linux/io.h>
15f77fbdf9SAlexey Charkov #include <linux/bcd.h>
16f77fbdf9SAlexey Charkov #include <linux/platform_device.h>
17f77fbdf9SAlexey Charkov #include <linux/slab.h>
187f4b48b3STony Prisk #include <linux/of.h>
19f77fbdf9SAlexey Charkov
20f77fbdf9SAlexey Charkov /*
21f77fbdf9SAlexey Charkov * Register definitions
22f77fbdf9SAlexey Charkov */
23f77fbdf9SAlexey Charkov #define VT8500_RTC_TS 0x00 /* Time set */
24f77fbdf9SAlexey Charkov #define VT8500_RTC_DS 0x04 /* Date set */
25f77fbdf9SAlexey Charkov #define VT8500_RTC_AS 0x08 /* Alarm set */
26f77fbdf9SAlexey Charkov #define VT8500_RTC_CR 0x0c /* Control */
27f77fbdf9SAlexey Charkov #define VT8500_RTC_TR 0x10 /* Time read */
28f77fbdf9SAlexey Charkov #define VT8500_RTC_DR 0x14 /* Date read */
29f77fbdf9SAlexey Charkov #define VT8500_RTC_WS 0x18 /* Write status */
30f77fbdf9SAlexey Charkov #define VT8500_RTC_CL 0x20 /* Calibration */
31f77fbdf9SAlexey Charkov #define VT8500_RTC_IS 0x24 /* Interrupt status */
32f77fbdf9SAlexey Charkov #define VT8500_RTC_ST 0x28 /* Status */
33f77fbdf9SAlexey Charkov
34f77fbdf9SAlexey Charkov #define INVALID_TIME_BIT (1 << 31)
35f77fbdf9SAlexey Charkov
36f77fbdf9SAlexey Charkov #define DATE_CENTURY_S 19
37f77fbdf9SAlexey Charkov #define DATE_YEAR_S 11
38f77fbdf9SAlexey Charkov #define DATE_YEAR_MASK (0xff << DATE_YEAR_S)
39f77fbdf9SAlexey Charkov #define DATE_MONTH_S 6
40f77fbdf9SAlexey Charkov #define DATE_MONTH_MASK (0x1f << DATE_MONTH_S)
41f77fbdf9SAlexey Charkov #define DATE_DAY_MASK 0x3f
42f77fbdf9SAlexey Charkov
43f77fbdf9SAlexey Charkov #define TIME_DOW_S 20
44f77fbdf9SAlexey Charkov #define TIME_DOW_MASK (0x07 << TIME_DOW_S)
45f77fbdf9SAlexey Charkov #define TIME_HOUR_S 14
46f77fbdf9SAlexey Charkov #define TIME_HOUR_MASK (0x3f << TIME_HOUR_S)
47f77fbdf9SAlexey Charkov #define TIME_MIN_S 7
48f77fbdf9SAlexey Charkov #define TIME_MIN_MASK (0x7f << TIME_MIN_S)
49f77fbdf9SAlexey Charkov #define TIME_SEC_MASK 0x7f
50f77fbdf9SAlexey Charkov
51f77fbdf9SAlexey Charkov #define ALARM_DAY_S 20
52f77fbdf9SAlexey Charkov #define ALARM_DAY_MASK (0x3f << ALARM_DAY_S)
53f77fbdf9SAlexey Charkov
54f77fbdf9SAlexey Charkov #define ALARM_DAY_BIT (1 << 29)
55f77fbdf9SAlexey Charkov #define ALARM_HOUR_BIT (1 << 28)
56f77fbdf9SAlexey Charkov #define ALARM_MIN_BIT (1 << 27)
57f77fbdf9SAlexey Charkov #define ALARM_SEC_BIT (1 << 26)
58f77fbdf9SAlexey Charkov
59f77fbdf9SAlexey Charkov #define ALARM_ENABLE_MASK (ALARM_DAY_BIT \
60f77fbdf9SAlexey Charkov | ALARM_HOUR_BIT \
61f77fbdf9SAlexey Charkov | ALARM_MIN_BIT \
62f77fbdf9SAlexey Charkov | ALARM_SEC_BIT)
63f77fbdf9SAlexey Charkov
64f77fbdf9SAlexey Charkov #define VT8500_RTC_CR_ENABLE (1 << 0) /* Enable RTC */
65532db570STony Prisk #define VT8500_RTC_CR_12H (1 << 1) /* 12h time format */
66f77fbdf9SAlexey Charkov #define VT8500_RTC_CR_SM_ENABLE (1 << 2) /* Enable periodic irqs */
67f77fbdf9SAlexey Charkov #define VT8500_RTC_CR_SM_SEC (1 << 3) /* 0: 1Hz/60, 1: 1Hz */
68f77fbdf9SAlexey Charkov #define VT8500_RTC_CR_CALIB (1 << 4) /* Enable calibration */
69f77fbdf9SAlexey Charkov
7007187ee1SWolfram Sang #define VT8500_RTC_IS_ALARM (1 << 0) /* Alarm interrupt status */
7107187ee1SWolfram Sang
72f77fbdf9SAlexey Charkov struct vt8500_rtc {
73f77fbdf9SAlexey Charkov void __iomem *regbase;
74f77fbdf9SAlexey Charkov int irq_alarm;
75f77fbdf9SAlexey Charkov struct rtc_device *rtc;
76f77fbdf9SAlexey Charkov spinlock_t lock; /* Protects this structure */
77f77fbdf9SAlexey Charkov };
78f77fbdf9SAlexey Charkov
vt8500_rtc_irq(int irq,void * dev_id)79f77fbdf9SAlexey Charkov static irqreturn_t vt8500_rtc_irq(int irq, void *dev_id)
80f77fbdf9SAlexey Charkov {
81f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = dev_id;
82f77fbdf9SAlexey Charkov u32 isr;
83f77fbdf9SAlexey Charkov unsigned long events = 0;
84f77fbdf9SAlexey Charkov
85f77fbdf9SAlexey Charkov spin_lock(&vt8500_rtc->lock);
86f77fbdf9SAlexey Charkov
87f77fbdf9SAlexey Charkov /* clear interrupt sources */
88f77fbdf9SAlexey Charkov isr = readl(vt8500_rtc->regbase + VT8500_RTC_IS);
89f77fbdf9SAlexey Charkov writel(isr, vt8500_rtc->regbase + VT8500_RTC_IS);
90f77fbdf9SAlexey Charkov
91f77fbdf9SAlexey Charkov spin_unlock(&vt8500_rtc->lock);
92f77fbdf9SAlexey Charkov
9307187ee1SWolfram Sang if (isr & VT8500_RTC_IS_ALARM)
94f77fbdf9SAlexey Charkov events |= RTC_AF | RTC_IRQF;
95f77fbdf9SAlexey Charkov
96f77fbdf9SAlexey Charkov rtc_update_irq(vt8500_rtc->rtc, 1, events);
97f77fbdf9SAlexey Charkov
98f77fbdf9SAlexey Charkov return IRQ_HANDLED;
99f77fbdf9SAlexey Charkov }
100f77fbdf9SAlexey Charkov
vt8500_rtc_read_time(struct device * dev,struct rtc_time * tm)101f77fbdf9SAlexey Charkov static int vt8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
102f77fbdf9SAlexey Charkov {
103f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
104f77fbdf9SAlexey Charkov u32 date, time;
105f77fbdf9SAlexey Charkov
106f77fbdf9SAlexey Charkov date = readl(vt8500_rtc->regbase + VT8500_RTC_DR);
107f77fbdf9SAlexey Charkov time = readl(vt8500_rtc->regbase + VT8500_RTC_TR);
108f77fbdf9SAlexey Charkov
109f77fbdf9SAlexey Charkov tm->tm_sec = bcd2bin(time & TIME_SEC_MASK);
110f77fbdf9SAlexey Charkov tm->tm_min = bcd2bin((time & TIME_MIN_MASK) >> TIME_MIN_S);
111f77fbdf9SAlexey Charkov tm->tm_hour = bcd2bin((time & TIME_HOUR_MASK) >> TIME_HOUR_S);
112f77fbdf9SAlexey Charkov tm->tm_mday = bcd2bin(date & DATE_DAY_MASK);
1132f90b683STony Prisk tm->tm_mon = bcd2bin((date & DATE_MONTH_MASK) >> DATE_MONTH_S) - 1;
114f77fbdf9SAlexey Charkov tm->tm_year = bcd2bin((date & DATE_YEAR_MASK) >> DATE_YEAR_S)
115f77fbdf9SAlexey Charkov + ((date >> DATE_CENTURY_S) & 1 ? 200 : 100);
116f77fbdf9SAlexey Charkov tm->tm_wday = (time & TIME_DOW_MASK) >> TIME_DOW_S;
117f77fbdf9SAlexey Charkov
118f77fbdf9SAlexey Charkov return 0;
119f77fbdf9SAlexey Charkov }
120f77fbdf9SAlexey Charkov
vt8500_rtc_set_time(struct device * dev,struct rtc_time * tm)121f77fbdf9SAlexey Charkov static int vt8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
122f77fbdf9SAlexey Charkov {
123f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
124f77fbdf9SAlexey Charkov
1253bdf8cd3STony Prisk writel((bin2bcd(tm->tm_year % 100) << DATE_YEAR_S)
1262f90b683STony Prisk | (bin2bcd(tm->tm_mon + 1) << DATE_MONTH_S)
1272f90b683STony Prisk | (bin2bcd(tm->tm_mday))
1282f90b683STony Prisk | ((tm->tm_year >= 200) << DATE_CENTURY_S),
129f77fbdf9SAlexey Charkov vt8500_rtc->regbase + VT8500_RTC_DS);
130f77fbdf9SAlexey Charkov writel((bin2bcd(tm->tm_wday) << TIME_DOW_S)
131f77fbdf9SAlexey Charkov | (bin2bcd(tm->tm_hour) << TIME_HOUR_S)
132f77fbdf9SAlexey Charkov | (bin2bcd(tm->tm_min) << TIME_MIN_S)
133f77fbdf9SAlexey Charkov | (bin2bcd(tm->tm_sec)),
134f77fbdf9SAlexey Charkov vt8500_rtc->regbase + VT8500_RTC_TS);
135f77fbdf9SAlexey Charkov
136f77fbdf9SAlexey Charkov return 0;
137f77fbdf9SAlexey Charkov }
138f77fbdf9SAlexey Charkov
vt8500_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alrm)139f77fbdf9SAlexey Charkov static int vt8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
140f77fbdf9SAlexey Charkov {
141f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
142f77fbdf9SAlexey Charkov u32 isr, alarm;
143f77fbdf9SAlexey Charkov
144f77fbdf9SAlexey Charkov alarm = readl(vt8500_rtc->regbase + VT8500_RTC_AS);
145f77fbdf9SAlexey Charkov isr = readl(vt8500_rtc->regbase + VT8500_RTC_IS);
146f77fbdf9SAlexey Charkov
147f77fbdf9SAlexey Charkov alrm->time.tm_mday = bcd2bin((alarm & ALARM_DAY_MASK) >> ALARM_DAY_S);
148f77fbdf9SAlexey Charkov alrm->time.tm_hour = bcd2bin((alarm & TIME_HOUR_MASK) >> TIME_HOUR_S);
149f77fbdf9SAlexey Charkov alrm->time.tm_min = bcd2bin((alarm & TIME_MIN_MASK) >> TIME_MIN_S);
150f77fbdf9SAlexey Charkov alrm->time.tm_sec = bcd2bin((alarm & TIME_SEC_MASK));
151f77fbdf9SAlexey Charkov
152f77fbdf9SAlexey Charkov alrm->enabled = (alarm & ALARM_ENABLE_MASK) ? 1 : 0;
15307187ee1SWolfram Sang alrm->pending = (isr & VT8500_RTC_IS_ALARM) ? 1 : 0;
154f77fbdf9SAlexey Charkov
155f77fbdf9SAlexey Charkov return rtc_valid_tm(&alrm->time);
156f77fbdf9SAlexey Charkov }
157f77fbdf9SAlexey Charkov
vt8500_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)158f77fbdf9SAlexey Charkov static int vt8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
159f77fbdf9SAlexey Charkov {
160f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
161f77fbdf9SAlexey Charkov
162f77fbdf9SAlexey Charkov writel((alrm->enabled ? ALARM_ENABLE_MASK : 0)
163f77fbdf9SAlexey Charkov | (bin2bcd(alrm->time.tm_mday) << ALARM_DAY_S)
164f77fbdf9SAlexey Charkov | (bin2bcd(alrm->time.tm_hour) << TIME_HOUR_S)
165f77fbdf9SAlexey Charkov | (bin2bcd(alrm->time.tm_min) << TIME_MIN_S)
166f77fbdf9SAlexey Charkov | (bin2bcd(alrm->time.tm_sec)),
167f77fbdf9SAlexey Charkov vt8500_rtc->regbase + VT8500_RTC_AS);
168f77fbdf9SAlexey Charkov
169f77fbdf9SAlexey Charkov return 0;
170f77fbdf9SAlexey Charkov }
171f77fbdf9SAlexey Charkov
vt8500_alarm_irq_enable(struct device * dev,unsigned int enabled)172f77fbdf9SAlexey Charkov static int vt8500_alarm_irq_enable(struct device *dev, unsigned int enabled)
173f77fbdf9SAlexey Charkov {
174f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
175f77fbdf9SAlexey Charkov unsigned long tmp = readl(vt8500_rtc->regbase + VT8500_RTC_AS);
176f77fbdf9SAlexey Charkov
177f77fbdf9SAlexey Charkov if (enabled)
178f77fbdf9SAlexey Charkov tmp |= ALARM_ENABLE_MASK;
179f77fbdf9SAlexey Charkov else
180f77fbdf9SAlexey Charkov tmp &= ~ALARM_ENABLE_MASK;
181f77fbdf9SAlexey Charkov
182f77fbdf9SAlexey Charkov writel(tmp, vt8500_rtc->regbase + VT8500_RTC_AS);
183f77fbdf9SAlexey Charkov return 0;
184f77fbdf9SAlexey Charkov }
185f77fbdf9SAlexey Charkov
186f77fbdf9SAlexey Charkov static const struct rtc_class_ops vt8500_rtc_ops = {
187f77fbdf9SAlexey Charkov .read_time = vt8500_rtc_read_time,
188f77fbdf9SAlexey Charkov .set_time = vt8500_rtc_set_time,
189f77fbdf9SAlexey Charkov .read_alarm = vt8500_rtc_read_alarm,
190f77fbdf9SAlexey Charkov .set_alarm = vt8500_rtc_set_alarm,
191f77fbdf9SAlexey Charkov .alarm_irq_enable = vt8500_alarm_irq_enable,
192f77fbdf9SAlexey Charkov };
193f77fbdf9SAlexey Charkov
vt8500_rtc_probe(struct platform_device * pdev)1945a167f45SGreg Kroah-Hartman static int vt8500_rtc_probe(struct platform_device *pdev)
195f77fbdf9SAlexey Charkov {
196f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc;
197f77fbdf9SAlexey Charkov int ret;
198f77fbdf9SAlexey Charkov
1990d7ecb83SDevendra Naga vt8500_rtc = devm_kzalloc(&pdev->dev,
2000d7ecb83SDevendra Naga sizeof(struct vt8500_rtc), GFP_KERNEL);
201f77fbdf9SAlexey Charkov if (!vt8500_rtc)
202f77fbdf9SAlexey Charkov return -ENOMEM;
203f77fbdf9SAlexey Charkov
204f77fbdf9SAlexey Charkov spin_lock_init(&vt8500_rtc->lock);
205f77fbdf9SAlexey Charkov platform_set_drvdata(pdev, vt8500_rtc);
206f77fbdf9SAlexey Charkov
207f77fbdf9SAlexey Charkov vt8500_rtc->irq_alarm = platform_get_irq(pdev, 0);
208faac9102SStephen Boyd if (vt8500_rtc->irq_alarm < 0)
20958f27d7dSSachin Kamat return vt8500_rtc->irq_alarm;
210f77fbdf9SAlexey Charkov
21109ef18bcSYueHaibing vt8500_rtc->regbase = devm_platform_ioremap_resource(pdev, 0);
212caa3af25SJingoo Han if (IS_ERR(vt8500_rtc->regbase))
213caa3af25SJingoo Han return PTR_ERR(vt8500_rtc->regbase);
214f77fbdf9SAlexey Charkov
21503ad2d50SAlexey Charkov /* Enable RTC and set it to 24-hour mode */
216532db570STony Prisk writel(VT8500_RTC_CR_ENABLE,
217f77fbdf9SAlexey Charkov vt8500_rtc->regbase + VT8500_RTC_CR);
218f77fbdf9SAlexey Charkov
219d8bced4bSAlexandre Belloni vt8500_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
2203e7d6397SAlexandre Belloni if (IS_ERR(vt8500_rtc->rtc))
221e979d049SAlexandre Belloni return PTR_ERR(vt8500_rtc->rtc);
222f77fbdf9SAlexey Charkov
223d8bced4bSAlexandre Belloni vt8500_rtc->rtc->ops = &vt8500_rtc_ops;
2241a064850SAlexandre Belloni vt8500_rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
2251a064850SAlexandre Belloni vt8500_rtc->rtc->range_max = RTC_TIMESTAMP_END_2199;
226d8bced4bSAlexandre Belloni
2270db29c1dSJingoo Han ret = devm_request_irq(&pdev->dev, vt8500_rtc->irq_alarm,
2280db29c1dSJingoo Han vt8500_rtc_irq, 0, "rtc alarm", vt8500_rtc);
229f77fbdf9SAlexey Charkov if (ret < 0) {
230f77fbdf9SAlexey Charkov dev_err(&pdev->dev, "can't get irq %i, err %d\n",
231f77fbdf9SAlexey Charkov vt8500_rtc->irq_alarm, ret);
232e979d049SAlexandre Belloni return ret;
233f77fbdf9SAlexey Charkov }
234f77fbdf9SAlexey Charkov
235fdcfd854SBartosz Golaszewski return devm_rtc_register_device(vt8500_rtc->rtc);
236f77fbdf9SAlexey Charkov }
237f77fbdf9SAlexey Charkov
vt8500_rtc_remove(struct platform_device * pdev)238*5b106444SUwe Kleine-König static void vt8500_rtc_remove(struct platform_device *pdev)
239f77fbdf9SAlexey Charkov {
240f77fbdf9SAlexey Charkov struct vt8500_rtc *vt8500_rtc = platform_get_drvdata(pdev);
241f77fbdf9SAlexey Charkov
242f77fbdf9SAlexey Charkov /* Disable alarm matching */
243f77fbdf9SAlexey Charkov writel(0, vt8500_rtc->regbase + VT8500_RTC_IS);
244f77fbdf9SAlexey Charkov }
245f77fbdf9SAlexey Charkov
2467f4b48b3STony Prisk static const struct of_device_id wmt_dt_ids[] = {
2477f4b48b3STony Prisk { .compatible = "via,vt8500-rtc", },
2487f4b48b3STony Prisk {}
2497f4b48b3STony Prisk };
25073798d5cSJavier Martinez Canillas MODULE_DEVICE_TABLE(of, wmt_dt_ids);
2517f4b48b3STony Prisk
252f77fbdf9SAlexey Charkov static struct platform_driver vt8500_rtc_driver = {
253f77fbdf9SAlexey Charkov .probe = vt8500_rtc_probe,
254*5b106444SUwe Kleine-König .remove_new = vt8500_rtc_remove,
255f77fbdf9SAlexey Charkov .driver = {
256f77fbdf9SAlexey Charkov .name = "vt8500-rtc",
257ce6bafdfSSachin Kamat .of_match_table = wmt_dt_ids,
258f77fbdf9SAlexey Charkov },
259f77fbdf9SAlexey Charkov };
260f77fbdf9SAlexey Charkov
2610c4eae66SAxel Lin module_platform_driver(vt8500_rtc_driver);
262f77fbdf9SAlexey Charkov
263f77fbdf9SAlexey Charkov MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
264f77fbdf9SAlexey Charkov MODULE_DESCRIPTION("VIA VT8500 SoC Realtime Clock Driver (RTC)");
2657f4b48b3STony Prisk MODULE_LICENSE("GPL v2");
266f77fbdf9SAlexey Charkov MODULE_ALIAS("platform:vt8500-rtc");
267