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9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/rtc.h>
12#include <linux/clk.h>
13#include <linux/interrupt.h>
14#include <linux/pm.h>
15#include <linux/platform_device.h>
16#include <linux/io.h>
17#include <linux/slab.h>
18
19
20
21
22
23#define COH901331_ALARM 0x00U
24
25#define COH901331_SET_TIME 0x04U
26
27#define COH901331_VALID 0x08U
28
29#define COH901331_CUR_TIME 0x0cU
30
31#define COH901331_IRQ_EVENT 0x10U
32
33#define COH901331_IRQ_MASK 0x14U
34
35#define COH901331_IRQ_FORCE 0x18U
36
37
38
39
40
41
42
43struct coh901331_port {
44 struct rtc_device *rtc;
45 struct clk *clk;
46 u32 phybase;
47 u32 physize;
48 void __iomem *virtbase;
49 int irq;
50#ifdef CONFIG_PM
51 u32 irqmaskstore;
52#endif
53};
54
55static irqreturn_t coh901331_interrupt(int irq, void *data)
56{
57 struct coh901331_port *rtap = data;
58
59 clk_enable(rtap->clk);
60
61 writel(1, rtap->virtbase + COH901331_IRQ_EVENT);
62
63
64
65
66
67
68
69 writel(0, rtap->virtbase + COH901331_IRQ_MASK);
70 clk_disable(rtap->clk);
71
72
73 rtc_update_irq(rtap->rtc, 1, RTC_AF);
74
75 return IRQ_HANDLED;
76}
77
78static int coh901331_read_time(struct device *dev, struct rtc_time *tm)
79{
80 struct coh901331_port *rtap = dev_get_drvdata(dev);
81
82 clk_enable(rtap->clk);
83
84 if (readl(rtap->virtbase + COH901331_VALID)) {
85 rtc_time_to_tm(readl(rtap->virtbase + COH901331_CUR_TIME), tm);
86 clk_disable(rtap->clk);
87 return rtc_valid_tm(tm);
88 }
89 clk_disable(rtap->clk);
90 return -EINVAL;
91}
92
93static int coh901331_set_mmss(struct device *dev, unsigned long secs)
94{
95 struct coh901331_port *rtap = dev_get_drvdata(dev);
96
97 clk_enable(rtap->clk);
98 writel(secs, rtap->virtbase + COH901331_SET_TIME);
99 clk_disable(rtap->clk);
100
101 return 0;
102}
103
104static int coh901331_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
105{
106 struct coh901331_port *rtap = dev_get_drvdata(dev);
107
108 clk_enable(rtap->clk);
109 rtc_time_to_tm(readl(rtap->virtbase + COH901331_ALARM), &alarm->time);
110 alarm->pending = readl(rtap->virtbase + COH901331_IRQ_EVENT) & 1U;
111 alarm->enabled = readl(rtap->virtbase + COH901331_IRQ_MASK) & 1U;
112 clk_disable(rtap->clk);
113
114 return 0;
115}
116
117static int coh901331_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
118{
119 struct coh901331_port *rtap = dev_get_drvdata(dev);
120 unsigned long time;
121
122 rtc_tm_to_time(&alarm->time, &time);
123 clk_enable(rtap->clk);
124 writel(time, rtap->virtbase + COH901331_ALARM);
125 writel(alarm->enabled, rtap->virtbase + COH901331_IRQ_MASK);
126 clk_disable(rtap->clk);
127
128 return 0;
129}
130
131static int coh901331_alarm_irq_enable(struct device *dev, unsigned int enabled)
132{
133 struct coh901331_port *rtap = dev_get_drvdata(dev);
134
135 clk_enable(rtap->clk);
136 if (enabled)
137 writel(1, rtap->virtbase + COH901331_IRQ_MASK);
138 else
139 writel(0, rtap->virtbase + COH901331_IRQ_MASK);
140 clk_disable(rtap->clk);
141
142 return 0;
143}
144
145static struct rtc_class_ops coh901331_ops = {
146 .read_time = coh901331_read_time,
147 .set_mmss = coh901331_set_mmss,
148 .read_alarm = coh901331_read_alarm,
149 .set_alarm = coh901331_set_alarm,
150 .alarm_irq_enable = coh901331_alarm_irq_enable,
151};
152
153static int __exit coh901331_remove(struct platform_device *pdev)
154{
155 struct coh901331_port *rtap = dev_get_drvdata(&pdev->dev);
156
157 if (rtap) {
158 free_irq(rtap->irq, rtap);
159 rtc_device_unregister(rtap->rtc);
160 clk_put(rtap->clk);
161 iounmap(rtap->virtbase);
162 release_mem_region(rtap->phybase, rtap->physize);
163 platform_set_drvdata(pdev, NULL);
164 kfree(rtap);
165 }
166
167 return 0;
168}
169
170
171static int __init coh901331_probe(struct platform_device *pdev)
172{
173 int ret;
174 struct coh901331_port *rtap;
175 struct resource *res;
176
177 rtap = kzalloc(sizeof(struct coh901331_port), GFP_KERNEL);
178 if (!rtap)
179 return -ENOMEM;
180
181 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
182 if (!res) {
183 ret = -ENOENT;
184 goto out_no_resource;
185 }
186 rtap->phybase = res->start;
187 rtap->physize = resource_size(res);
188
189 if (request_mem_region(rtap->phybase, rtap->physize,
190 "rtc-coh901331") == NULL) {
191 ret = -EBUSY;
192 goto out_no_memregion;
193 }
194
195 rtap->virtbase = ioremap(rtap->phybase, rtap->physize);
196 if (!rtap->virtbase) {
197 ret = -ENOMEM;
198 goto out_no_remap;
199 }
200
201 rtap->irq = platform_get_irq(pdev, 0);
202 if (request_irq(rtap->irq, coh901331_interrupt, IRQF_DISABLED,
203 "RTC COH 901 331 Alarm", rtap)) {
204 ret = -EIO;
205 goto out_no_irq;
206 }
207
208 rtap->clk = clk_get(&pdev->dev, NULL);
209 if (IS_ERR(rtap->clk)) {
210 ret = PTR_ERR(rtap->clk);
211 dev_err(&pdev->dev, "could not get clock\n");
212 goto out_no_clk;
213 }
214
215
216 ret = clk_enable(rtap->clk);
217 if (ret) {
218 dev_err(&pdev->dev, "could not enable clock\n");
219 goto out_no_clk_enable;
220 }
221 clk_disable(rtap->clk);
222
223 platform_set_drvdata(pdev, rtap);
224 rtap->rtc = rtc_device_register("coh901331", &pdev->dev, &coh901331_ops,
225 THIS_MODULE);
226 if (IS_ERR(rtap->rtc)) {
227 ret = PTR_ERR(rtap->rtc);
228 goto out_no_rtc;
229 }
230
231 return 0;
232
233 out_no_rtc:
234 platform_set_drvdata(pdev, NULL);
235 out_no_clk_enable:
236 clk_put(rtap->clk);
237 out_no_clk:
238 free_irq(rtap->irq, rtap);
239 out_no_irq:
240 iounmap(rtap->virtbase);
241 out_no_remap:
242 platform_set_drvdata(pdev, NULL);
243 out_no_memregion:
244 release_mem_region(rtap->phybase, SZ_4K);
245 out_no_resource:
246 kfree(rtap);
247 return ret;
248}
249
250#ifdef CONFIG_PM
251static int coh901331_suspend(struct platform_device *pdev, pm_message_t state)
252{
253 struct coh901331_port *rtap = dev_get_drvdata(&pdev->dev);
254
255
256
257
258
259
260 if (device_may_wakeup(&pdev->dev)) {
261 enable_irq_wake(rtap->irq);
262 } else {
263 clk_enable(rtap->clk);
264 rtap->irqmaskstore = readl(rtap->virtbase + COH901331_IRQ_MASK);
265 writel(0, rtap->virtbase + COH901331_IRQ_MASK);
266 clk_disable(rtap->clk);
267 }
268 return 0;
269}
270
271static int coh901331_resume(struct platform_device *pdev)
272{
273 struct coh901331_port *rtap = dev_get_drvdata(&pdev->dev);
274
275 if (device_may_wakeup(&pdev->dev)) {
276 disable_irq_wake(rtap->irq);
277 } else {
278 clk_enable(rtap->clk);
279 writel(rtap->irqmaskstore, rtap->virtbase + COH901331_IRQ_MASK);
280 clk_disable(rtap->clk);
281 }
282 return 0;
283}
284#else
285#define coh901331_suspend NULL
286#define coh901331_resume NULL
287#endif
288
289static void coh901331_shutdown(struct platform_device *pdev)
290{
291 struct coh901331_port *rtap = dev_get_drvdata(&pdev->dev);
292
293 clk_enable(rtap->clk);
294 writel(0, rtap->virtbase + COH901331_IRQ_MASK);
295 clk_disable(rtap->clk);
296}
297
298static struct platform_driver coh901331_driver = {
299 .driver = {
300 .name = "rtc-coh901331",
301 .owner = THIS_MODULE,
302 },
303 .remove = __exit_p(coh901331_remove),
304 .suspend = coh901331_suspend,
305 .resume = coh901331_resume,
306 .shutdown = coh901331_shutdown,
307};
308
309static int __init coh901331_init(void)
310{
311 return platform_driver_probe(&coh901331_driver, coh901331_probe);
312}
313
314static void __exit coh901331_exit(void)
315{
316 platform_driver_unregister(&coh901331_driver);
317}
318
319module_init(coh901331_init);
320module_exit(coh901331_exit);
321
322MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
323MODULE_DESCRIPTION("ST-Ericsson AB COH 901 331 RTC Driver");
324MODULE_LICENSE("GPL");
325
