2 * Oki MSM6242 RTC Driver
4 * Copyright 2009 Geert Uytterhoeven
6 * Based on the A2000 TOD code in arch/m68k/amiga/config.c
7 * Copyright (C) 1993 Hamish Macdonald
10 #include <linux/delay.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/rtc.h>
19 MSM6242_SECOND1 = 0x0, /* 1-second digit register */
20 MSM6242_SECOND10 = 0x1, /* 10-second digit register */
21 MSM6242_MINUTE1 = 0x2, /* 1-minute digit register */
22 MSM6242_MINUTE10 = 0x3, /* 10-minute digit register */
23 MSM6242_HOUR1 = 0x4, /* 1-hour digit register */
24 MSM6242_HOUR10 = 0x5, /* PM/AM, 10-hour digit register */
25 MSM6242_DAY1 = 0x6, /* 1-day digit register */
26 MSM6242_DAY10 = 0x7, /* 10-day digit register */
27 MSM6242_MONTH1 = 0x8, /* 1-month digit register */
28 MSM6242_MONTH10 = 0x9, /* 10-month digit register */
29 MSM6242_YEAR1 = 0xa, /* 1-year digit register */
30 MSM6242_YEAR10 = 0xb, /* 10-year digit register */
31 MSM6242_WEEK = 0xc, /* Week register */
32 MSM6242_CD = 0xd, /* Control Register D */
33 MSM6242_CE = 0xe, /* Control Register E */
34 MSM6242_CF = 0xf, /* Control Register F */
37 #define MSM6242_HOUR10_AM (0 << 2)
38 #define MSM6242_HOUR10_PM (1 << 2)
39 #define MSM6242_HOUR10_HR_MASK (3 << 0)
41 #define MSM6242_WEEK_SUNDAY 0
42 #define MSM6242_WEEK_MONDAY 1
43 #define MSM6242_WEEK_TUESDAY 2
44 #define MSM6242_WEEK_WEDNESDAY 3
45 #define MSM6242_WEEK_THURSDAY 4
46 #define MSM6242_WEEK_FRIDAY 5
47 #define MSM6242_WEEK_SATURDAY 6
49 #define MSM6242_CD_30_S_ADJ (1 << 3) /* 30-second adjustment */
50 #define MSM6242_CD_IRQ_FLAG (1 << 2)
51 #define MSM6242_CD_BUSY (1 << 1)
52 #define MSM6242_CD_HOLD (1 << 0)
54 #define MSM6242_CE_T_MASK (3 << 2)
55 #define MSM6242_CE_T_64HZ (0 << 2) /* period 1/64 second */
56 #define MSM6242_CE_T_1HZ (1 << 2) /* period 1 second */
57 #define MSM6242_CE_T_1MINUTE (2 << 2) /* period 1 minute */
58 #define MSM6242_CE_T_1HOUR (3 << 2) /* period 1 hour */
60 #define MSM6242_CE_ITRPT_STND (1 << 1)
61 #define MSM6242_CE_MASK (1 << 0) /* STD.P output control */
63 #define MSM6242_CF_TEST (1 << 3)
64 #define MSM6242_CF_12H (0 << 2)
65 #define MSM6242_CF_24H (1 << 2)
66 #define MSM6242_CF_STOP (1 << 1)
67 #define MSM6242_CF_REST (1 << 0) /* reset */
72 struct rtc_device *rtc;
75 static inline unsigned int msm6242_read(struct msm6242_priv *priv,
78 return __raw_readl(&priv->regs[reg]) & 0xf;
81 static inline void msm6242_write(struct msm6242_priv *priv, unsigned int val,
84 return __raw_writel(val, &priv->regs[reg]);
87 static inline void msm6242_set(struct msm6242_priv *priv, unsigned int val,
90 msm6242_write(priv, msm6242_read(priv, reg) | val, reg);
93 static inline void msm6242_clear(struct msm6242_priv *priv, unsigned int val,
96 msm6242_write(priv, msm6242_read(priv, reg) & ~val, reg);
99 static void msm6242_lock(struct msm6242_priv *priv)
103 msm6242_set(priv, MSM6242_CD_HOLD, MSM6242_CD);
105 while ((msm6242_read(priv, MSM6242_CD) & MSM6242_CD_BUSY) && cnt) {
106 msm6242_clear(priv, MSM6242_CD_HOLD, MSM6242_CD);
108 msm6242_set(priv, MSM6242_CD_HOLD, MSM6242_CD);
113 pr_warning("msm6242: timed out waiting for RTC (0x%x)\n",
114 msm6242_read(priv, MSM6242_CD));
117 static void msm6242_unlock(struct msm6242_priv *priv)
119 msm6242_clear(priv, MSM6242_CD_HOLD, MSM6242_CD);
122 static int msm6242_read_time(struct device *dev, struct rtc_time *tm)
124 struct msm6242_priv *priv = dev_get_drvdata(dev);
128 tm->tm_sec = msm6242_read(priv, MSM6242_SECOND10) * 10 +
129 msm6242_read(priv, MSM6242_SECOND1);
130 tm->tm_min = msm6242_read(priv, MSM6242_MINUTE10) * 10 +
131 msm6242_read(priv, MSM6242_MINUTE1);
132 tm->tm_hour = (msm6242_read(priv, MSM6242_HOUR10 & 3)) * 10 +
133 msm6242_read(priv, MSM6242_HOUR1);
134 tm->tm_mday = msm6242_read(priv, MSM6242_DAY10) * 10 +
135 msm6242_read(priv, MSM6242_DAY1);
136 tm->tm_wday = msm6242_read(priv, MSM6242_WEEK);
137 tm->tm_mon = msm6242_read(priv, MSM6242_MONTH10) * 10 +
138 msm6242_read(priv, MSM6242_MONTH1) - 1;
139 tm->tm_year = msm6242_read(priv, MSM6242_YEAR10) * 10 +
140 msm6242_read(priv, MSM6242_YEAR1);
141 if (tm->tm_year <= 69)
144 if (!(msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)) {
145 unsigned int pm = msm6242_read(priv, MSM6242_HOUR10) &
147 if (!pm && tm->tm_hour == 12)
149 else if (pm && tm->tm_hour != 12)
153 msm6242_unlock(priv);
155 return rtc_valid_tm(tm);
158 static int msm6242_set_time(struct device *dev, struct rtc_time *tm)
160 struct msm6242_priv *priv = dev_get_drvdata(dev);
164 msm6242_write(priv, tm->tm_sec / 10, MSM6242_SECOND10);
165 msm6242_write(priv, tm->tm_sec % 10, MSM6242_SECOND1);
166 msm6242_write(priv, tm->tm_min / 10, MSM6242_MINUTE10);
167 msm6242_write(priv, tm->tm_min % 10, MSM6242_MINUTE1);
168 if (msm6242_read(priv, MSM6242_CF) & MSM6242_CF_24H)
169 msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
170 else if (tm->tm_hour >= 12)
171 msm6242_write(priv, MSM6242_HOUR10_PM + (tm->tm_hour - 12) / 10,
174 msm6242_write(priv, tm->tm_hour / 10, MSM6242_HOUR10);
175 msm6242_write(priv, tm->tm_hour % 10, MSM6242_HOUR1);
176 msm6242_write(priv, tm->tm_mday / 10, MSM6242_DAY10);
177 msm6242_write(priv, tm->tm_mday % 10, MSM6242_DAY1);
178 if (tm->tm_wday != -1)
179 msm6242_write(priv, tm->tm_wday, MSM6242_WEEK);
180 msm6242_write(priv, (tm->tm_mon + 1) / 10, MSM6242_MONTH10);
181 msm6242_write(priv, (tm->tm_mon + 1) % 10, MSM6242_MONTH1);
182 if (tm->tm_year >= 100)
184 msm6242_write(priv, tm->tm_year / 10, MSM6242_YEAR10);
185 msm6242_write(priv, tm->tm_year % 10, MSM6242_YEAR1);
187 msm6242_unlock(priv);
191 static const struct rtc_class_ops msm6242_rtc_ops = {
192 .read_time = msm6242_read_time,
193 .set_time = msm6242_set_time,
196 static int __init msm6242_rtc_probe(struct platform_device *dev)
198 struct resource *res;
199 struct msm6242_priv *priv;
200 struct rtc_device *rtc;
203 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
207 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
211 priv->regs = ioremap(res->start, resource_size(res));
217 rtc = rtc_device_register("rtc-msm6242", &dev->dev, &msm6242_rtc_ops,
220 error = PTR_ERR(rtc);
225 platform_set_drvdata(dev, priv);
235 static int __exit msm6242_rtc_remove(struct platform_device *dev)
237 struct msm6242_priv *priv = platform_get_drvdata(dev);
239 rtc_device_unregister(priv->rtc);
245 static struct platform_driver msm6242_rtc_driver = {
247 .name = "rtc-msm6242",
248 .owner = THIS_MODULE,
250 .remove = __exit_p(msm6242_rtc_remove),
253 static int __init msm6242_rtc_init(void)
255 return platform_driver_probe(&msm6242_rtc_driver, msm6242_rtc_probe);
258 static void __exit msm6242_rtc_fini(void)
260 platform_driver_unregister(&msm6242_rtc_driver);
263 module_init(msm6242_rtc_init);
264 module_exit(msm6242_rtc_fini);
266 MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
267 MODULE_LICENSE("GPL");
268 MODULE_DESCRIPTION("Oki MSM6242 RTC driver");
269 MODULE_ALIAS("platform:rtc-msm6242");