1 /*
2 * RTC driver code specific to PKUnity SoC and UniCore ISA
3 *
4 * Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
5 * Copyright (C) 2001-2010 Guan Xuetao
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/module.h>
13 #include <linux/fs.h>
14 #include <linux/string.h>
15 #include <linux/init.h>
16 #include <linux/platform_device.h>
17 #include <linux/interrupt.h>
18 #include <linux/rtc.h>
19 #include <linux/bcd.h>
20 #include <linux/clk.h>
21 #include <linux/log2.h>
22 #include <linux/slab.h>
23 #include <linux/uaccess.h>
24 #include <linux/io.h>
25
26 #include <asm/irq.h>
27 #include <mach/hardware.h>
28
29 static struct resource *puv3_rtc_mem;
30
31 static int puv3_rtc_alarmno = IRQ_RTCAlarm;
32 static int puv3_rtc_tickno = IRQ_RTC;
33
34 static DEFINE_SPINLOCK(puv3_rtc_pie_lock);
35
36 /* IRQ Handlers */
puv3_rtc_alarmirq(int irq,void * id)37 static irqreturn_t puv3_rtc_alarmirq(int irq, void *id)
38 {
39 struct rtc_device *rdev = id;
40
41 writel(readl(RTC_RTSR) | RTC_RTSR_AL, RTC_RTSR);
42 rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
43 return IRQ_HANDLED;
44 }
45
puv3_rtc_tickirq(int irq,void * id)46 static irqreturn_t puv3_rtc_tickirq(int irq, void *id)
47 {
48 struct rtc_device *rdev = id;
49
50 writel(readl(RTC_RTSR) | RTC_RTSR_HZ, RTC_RTSR);
51 rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
52 return IRQ_HANDLED;
53 }
54
55 /* Update control registers */
puv3_rtc_setaie(struct device * dev,int to)56 static void puv3_rtc_setaie(struct device *dev, int to)
57 {
58 unsigned int tmp;
59
60 dev_dbg(dev, "%s: aie=%d\n", __func__, to);
61
62 tmp = readl(RTC_RTSR) & ~RTC_RTSR_ALE;
63
64 if (to)
65 tmp |= RTC_RTSR_ALE;
66
67 writel(tmp, RTC_RTSR);
68 }
69
puv3_rtc_setpie(struct device * dev,int enabled)70 static int puv3_rtc_setpie(struct device *dev, int enabled)
71 {
72 unsigned int tmp;
73
74 dev_dbg(dev, "%s: pie=%d\n", __func__, enabled);
75
76 spin_lock_irq(&puv3_rtc_pie_lock);
77 tmp = readl(RTC_RTSR) & ~RTC_RTSR_HZE;
78
79 if (enabled)
80 tmp |= RTC_RTSR_HZE;
81
82 writel(tmp, RTC_RTSR);
83 spin_unlock_irq(&puv3_rtc_pie_lock);
84
85 return 0;
86 }
87
88 /* Time read/write */
puv3_rtc_gettime(struct device * dev,struct rtc_time * rtc_tm)89 static int puv3_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
90 {
91 rtc_time_to_tm(readl(RTC_RCNR), rtc_tm);
92
93 dev_dbg(dev, "read time %02x.%02x.%02x %02x/%02x/%02x\n",
94 rtc_tm->tm_year, rtc_tm->tm_mon, rtc_tm->tm_mday,
95 rtc_tm->tm_hour, rtc_tm->tm_min, rtc_tm->tm_sec);
96
97 return 0;
98 }
99
puv3_rtc_settime(struct device * dev,struct rtc_time * tm)100 static int puv3_rtc_settime(struct device *dev, struct rtc_time *tm)
101 {
102 unsigned long rtc_count = 0;
103
104 dev_dbg(dev, "set time %02d.%02d.%02d %02d/%02d/%02d\n",
105 tm->tm_year, tm->tm_mon, tm->tm_mday,
106 tm->tm_hour, tm->tm_min, tm->tm_sec);
107
108 rtc_tm_to_time(tm, &rtc_count);
109 writel(rtc_count, RTC_RCNR);
110
111 return 0;
112 }
113
puv3_rtc_getalarm(struct device * dev,struct rtc_wkalrm * alrm)114 static int puv3_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
115 {
116 struct rtc_time *alm_tm = &alrm->time;
117
118 rtc_time_to_tm(readl(RTC_RTAR), alm_tm);
119
120 alrm->enabled = readl(RTC_RTSR) & RTC_RTSR_ALE;
121
122 dev_dbg(dev, "read alarm %02x %02x.%02x.%02x %02x/%02x/%02x\n",
123 alrm->enabled,
124 alm_tm->tm_year, alm_tm->tm_mon, alm_tm->tm_mday,
125 alm_tm->tm_hour, alm_tm->tm_min, alm_tm->tm_sec);
126
127 return 0;
128 }
129
puv3_rtc_setalarm(struct device * dev,struct rtc_wkalrm * alrm)130 static int puv3_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
131 {
132 struct rtc_time *tm = &alrm->time;
133 unsigned long rtcalarm_count = 0;
134
135 dev_dbg(dev, "puv3_rtc_setalarm: %d, %02x/%02x/%02x %02x.%02x.%02x\n",
136 alrm->enabled,
137 tm->tm_mday & 0xff, tm->tm_mon & 0xff, tm->tm_year & 0xff,
138 tm->tm_hour & 0xff, tm->tm_min & 0xff, tm->tm_sec);
139
140 rtc_tm_to_time(tm, &rtcalarm_count);
141 writel(rtcalarm_count, RTC_RTAR);
142
143 puv3_rtc_setaie(dev, alrm->enabled);
144
145 if (alrm->enabled)
146 enable_irq_wake(puv3_rtc_alarmno);
147 else
148 disable_irq_wake(puv3_rtc_alarmno);
149
150 return 0;
151 }
152
puv3_rtc_proc(struct device * dev,struct seq_file * seq)153 static int puv3_rtc_proc(struct device *dev, struct seq_file *seq)
154 {
155 seq_printf(seq, "periodic_IRQ\t: %s\n",
156 (readl(RTC_RTSR) & RTC_RTSR_HZE) ? "yes" : "no");
157 return 0;
158 }
159
160 static const struct rtc_class_ops puv3_rtcops = {
161 .read_time = puv3_rtc_gettime,
162 .set_time = puv3_rtc_settime,
163 .read_alarm = puv3_rtc_getalarm,
164 .set_alarm = puv3_rtc_setalarm,
165 .proc = puv3_rtc_proc,
166 };
167
puv3_rtc_enable(struct device * dev,int en)168 static void puv3_rtc_enable(struct device *dev, int en)
169 {
170 if (!en) {
171 writel(readl(RTC_RTSR) & ~RTC_RTSR_HZE, RTC_RTSR);
172 } else {
173 /* re-enable the device, and check it is ok */
174 if ((readl(RTC_RTSR) & RTC_RTSR_HZE) == 0) {
175 dev_info(dev, "rtc disabled, re-enabling\n");
176 writel(readl(RTC_RTSR) | RTC_RTSR_HZE, RTC_RTSR);
177 }
178 }
179 }
180
puv3_rtc_remove(struct platform_device * dev)181 static int puv3_rtc_remove(struct platform_device *dev)
182 {
183 puv3_rtc_setpie(&dev->dev, 0);
184 puv3_rtc_setaie(&dev->dev, 0);
185
186 release_resource(puv3_rtc_mem);
187 kfree(puv3_rtc_mem);
188
189 return 0;
190 }
191
puv3_rtc_probe(struct platform_device * pdev)192 static int puv3_rtc_probe(struct platform_device *pdev)
193 {
194 struct rtc_device *rtc;
195 struct resource *res;
196 int ret;
197
198 dev_dbg(&pdev->dev, "%s: probe=%p\n", __func__, pdev);
199
200 /* find the IRQs */
201 puv3_rtc_tickno = platform_get_irq(pdev, 1);
202 if (puv3_rtc_tickno < 0) {
203 dev_err(&pdev->dev, "no irq for rtc tick\n");
204 return -ENOENT;
205 }
206
207 puv3_rtc_alarmno = platform_get_irq(pdev, 0);
208 if (puv3_rtc_alarmno < 0) {
209 dev_err(&pdev->dev, "no irq for alarm\n");
210 return -ENOENT;
211 }
212
213 dev_dbg(&pdev->dev, "PKUnity_rtc: tick irq %d, alarm irq %d\n",
214 puv3_rtc_tickno, puv3_rtc_alarmno);
215
216 rtc = devm_rtc_allocate_device(&pdev->dev);
217 if (IS_ERR(rtc))
218 return PTR_ERR(rtc);
219
220 ret = devm_request_irq(&pdev->dev, puv3_rtc_alarmno, puv3_rtc_alarmirq,
221 0, "pkunity-rtc alarm", rtc);
222 if (ret) {
223 dev_err(&pdev->dev, "IRQ%d error %d\n", puv3_rtc_alarmno, ret);
224 return ret;
225 }
226
227 ret = devm_request_irq(&pdev->dev, puv3_rtc_tickno, puv3_rtc_tickirq,
228 0, "pkunity-rtc tick", rtc);
229 if (ret) {
230 dev_err(&pdev->dev, "IRQ%d error %d\n", puv3_rtc_tickno, ret);
231 return ret;
232 }
233
234 /* get the memory region */
235 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
236 if (res == NULL) {
237 dev_err(&pdev->dev, "failed to get memory region resource\n");
238 return -ENOENT;
239 }
240
241 puv3_rtc_mem = request_mem_region(res->start, resource_size(res),
242 pdev->name);
243
244 if (puv3_rtc_mem == NULL) {
245 dev_err(&pdev->dev, "failed to reserve memory region\n");
246 ret = -ENOENT;
247 goto err_nores;
248 }
249
250 puv3_rtc_enable(&pdev->dev, 1);
251
252 /* register RTC and exit */
253 rtc->ops = &puv3_rtcops;
254 ret = rtc_register_device(rtc);
255 if (ret) {
256 dev_err(&pdev->dev, "cannot attach rtc\n");
257 goto err_nortc;
258 }
259
260 /* platform setup code should have handled this; sigh */
261 if (!device_can_wakeup(&pdev->dev))
262 device_init_wakeup(&pdev->dev, 1);
263
264 platform_set_drvdata(pdev, rtc);
265 return 0;
266
267 err_nortc:
268 puv3_rtc_enable(&pdev->dev, 0);
269 release_resource(puv3_rtc_mem);
270
271 err_nores:
272 return ret;
273 }
274
275 #ifdef CONFIG_PM_SLEEP
276 static int ticnt_save;
277
puv3_rtc_suspend(struct device * dev)278 static int puv3_rtc_suspend(struct device *dev)
279 {
280 /* save RTAR for anyone using periodic interrupts */
281 ticnt_save = readl(RTC_RTAR);
282 puv3_rtc_enable(dev, 0);
283 return 0;
284 }
285
puv3_rtc_resume(struct device * dev)286 static int puv3_rtc_resume(struct device *dev)
287 {
288 puv3_rtc_enable(dev, 1);
289 writel(ticnt_save, RTC_RTAR);
290 return 0;
291 }
292 #endif
293
294 static SIMPLE_DEV_PM_OPS(puv3_rtc_pm_ops, puv3_rtc_suspend, puv3_rtc_resume);
295
296 static struct platform_driver puv3_rtc_driver = {
297 .probe = puv3_rtc_probe,
298 .remove = puv3_rtc_remove,
299 .driver = {
300 .name = "PKUnity-v3-RTC",
301 .pm = &puv3_rtc_pm_ops,
302 }
303 };
304
305 module_platform_driver(puv3_rtc_driver);
306
307 MODULE_DESCRIPTION("RTC Driver for the PKUnity v3 chip");
308 MODULE_AUTHOR("Hu Dongliang");
309 MODULE_LICENSE("GPL v2");
310
