1
2
3
4
5
6
7
8
9
10
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <linux/rtc.h>
16#include <linux/io.h>
17
18
19
20
21
22
23
24
25
26
27
28#define RTC_CTRL 0x00
29#define RTC_CTRL_EN 0
30#define RTC_CTRL_PCLR 1
31#define RTC_CTRL_TOPEN 2
32#define RTC_CTRL_PSEL 8
33
34#define RTC_VAL 0x04
35
36#define RTC_TOP 0x08
37
38#define RTC_IER 0x10
39#define RTC_IER_TOPI 0
40
41#define RTC_IDR 0x14
42#define RTC_IDR_TOPI 0
43
44#define RTC_IMR 0x18
45#define RTC_IMR_TOPI 0
46
47#define RTC_ISR 0x1c
48#define RTC_ISR_TOPI 0
49
50#define RTC_ICR 0x20
51#define RTC_ICR_TOPI 0
52
53#define RTC_BIT(name) (1 << RTC_##name)
54#define RTC_BF(name, value) ((value) << RTC_##name)
55
56#define rtc_readl(dev, reg) \
57 __raw_readl((dev)->regs + RTC_##reg)
58#define rtc_writel(dev, reg, value) \
59 __raw_writel((value), (dev)->regs + RTC_##reg)
60
61struct rtc_at32ap700x {
62 struct rtc_device *rtc;
63 void __iomem *regs;
64 unsigned long alarm_time;
65 unsigned long irq;
66
67 spinlock_t lock;
68};
69
70static int at32_rtc_readtime(struct device *dev, struct rtc_time *tm)
71{
72 struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
73 unsigned long now;
74
75 now = rtc_readl(rtc, VAL);
76 rtc_time_to_tm(now, tm);
77
78 return 0;
79}
80
81static int at32_rtc_settime(struct device *dev, struct rtc_time *tm)
82{
83 struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
84 unsigned long now;
85 int ret;
86
87 ret = rtc_tm_to_time(tm, &now);
88 if (ret == 0)
89 rtc_writel(rtc, VAL, now);
90
91 return ret;
92}
93
94static int at32_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
95{
96 struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
97
98 spin_lock_irq(&rtc->lock);
99 rtc_time_to_tm(rtc->alarm_time, &alrm->time);
100 alrm->enabled = rtc_readl(rtc, IMR) & RTC_BIT(IMR_TOPI) ? 1 : 0;
101 alrm->pending = rtc_readl(rtc, ISR) & RTC_BIT(ISR_TOPI) ? 1 : 0;
102 spin_unlock_irq(&rtc->lock);
103
104 return 0;
105}
106
107static int at32_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
108{
109 struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
110 unsigned long rtc_unix_time;
111 unsigned long alarm_unix_time;
112 int ret;
113
114 rtc_unix_time = rtc_readl(rtc, VAL);
115
116 ret = rtc_tm_to_time(&alrm->time, &alarm_unix_time);
117 if (ret)
118 return ret;
119
120 if (alarm_unix_time < rtc_unix_time)
121 return -EINVAL;
122
123 spin_lock_irq(&rtc->lock);
124 rtc->alarm_time = alarm_unix_time;
125 rtc_writel(rtc, TOP, rtc->alarm_time);
126 if (alrm->enabled)
127 rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
128 | RTC_BIT(CTRL_TOPEN));
129 else
130 rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
131 & ~RTC_BIT(CTRL_TOPEN));
132 spin_unlock_irq(&rtc->lock);
133
134 return ret;
135}
136
137static int at32_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
138{
139 struct rtc_at32ap700x *rtc = dev_get_drvdata(dev);
140 int ret = 0;
141
142 spin_lock_irq(&rtc->lock);
143
144 if(enabled) {
145 if (rtc_readl(rtc, VAL) > rtc->alarm_time) {
146 ret = -EINVAL;
147 goto out;
148 }
149 rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
150 | RTC_BIT(CTRL_TOPEN));
151 rtc_writel(rtc, ICR, RTC_BIT(ICR_TOPI));
152 rtc_writel(rtc, IER, RTC_BIT(IER_TOPI));
153 } else {
154 rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
155 & ~RTC_BIT(CTRL_TOPEN));
156 rtc_writel(rtc, IDR, RTC_BIT(IDR_TOPI));
157 rtc_writel(rtc, ICR, RTC_BIT(ICR_TOPI));
158 }
159out:
160 spin_unlock_irq(&rtc->lock);
161
162 return ret;
163}
164
165static irqreturn_t at32_rtc_interrupt(int irq, void *dev_id)
166{
167 struct rtc_at32ap700x *rtc = (struct rtc_at32ap700x *)dev_id;
168 unsigned long isr = rtc_readl(rtc, ISR);
169 unsigned long events = 0;
170 int ret = IRQ_NONE;
171
172 spin_lock(&rtc->lock);
173
174 if (isr & RTC_BIT(ISR_TOPI)) {
175 rtc_writel(rtc, ICR, RTC_BIT(ICR_TOPI));
176 rtc_writel(rtc, IDR, RTC_BIT(IDR_TOPI));
177 rtc_writel(rtc, CTRL, rtc_readl(rtc, CTRL)
178 & ~RTC_BIT(CTRL_TOPEN));
179 rtc_writel(rtc, VAL, rtc->alarm_time);
180 events = RTC_AF | RTC_IRQF;
181 rtc_update_irq(rtc->rtc, 1, events);
182 ret = IRQ_HANDLED;
183 }
184
185 spin_unlock(&rtc->lock);
186
187 return ret;
188}
189
190static struct rtc_class_ops at32_rtc_ops = {
191 .read_time = at32_rtc_readtime,
192 .set_time = at32_rtc_settime,
193 .read_alarm = at32_rtc_readalarm,
194 .set_alarm = at32_rtc_setalarm,
195 .alarm_irq_enable = at32_rtc_alarm_irq_enable,
196};
197
198static int __init at32_rtc_probe(struct platform_device *pdev)
199{
200 struct resource *regs;
201 struct rtc_at32ap700x *rtc;
202 int irq;
203 int ret;
204
205 rtc = devm_kzalloc(&pdev->dev, sizeof(struct rtc_at32ap700x),
206 GFP_KERNEL);
207 if (!rtc) {
208 dev_dbg(&pdev->dev, "out of memory\n");
209 return -ENOMEM;
210 }
211
212 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
213 if (!regs) {
214 dev_dbg(&pdev->dev, "no mmio resource defined\n");
215 ret = -ENXIO;
216 goto out;
217 }
218
219 irq = platform_get_irq(pdev, 0);
220 if (irq <= 0) {
221 dev_dbg(&pdev->dev, "could not get irq\n");
222 ret = -ENXIO;
223 goto out;
224 }
225
226 rtc->irq = irq;
227 rtc->regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
228 if (!rtc->regs) {
229 ret = -ENOMEM;
230 dev_dbg(&pdev->dev, "could not map I/O memory\n");
231 goto out;
232 }
233 spin_lock_init(&rtc->lock);
234
235
236
237
238
239
240
241 if (!(rtc_readl(rtc, CTRL) & RTC_BIT(CTRL_EN))) {
242 rtc_writel(rtc, CTRL, RTC_BIT(CTRL_PCLR));
243 rtc_writel(rtc, IDR, RTC_BIT(IDR_TOPI));
244 rtc_writel(rtc, CTRL, RTC_BF(CTRL_PSEL, 0xe)
245 | RTC_BIT(CTRL_EN));
246 }
247
248 ret = devm_request_irq(&pdev->dev, irq, at32_rtc_interrupt, IRQF_SHARED,
249 "rtc", rtc);
250 if (ret) {
251 dev_dbg(&pdev->dev, "could not request irq %d\n", irq);
252 goto out;
253 }
254
255 platform_set_drvdata(pdev, rtc);
256
257 rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
258 &at32_rtc_ops, THIS_MODULE);
259 if (IS_ERR(rtc->rtc)) {
260 dev_dbg(&pdev->dev, "could not register rtc device\n");
261 ret = PTR_ERR(rtc->rtc);
262 goto out;
263 }
264
265 device_init_wakeup(&pdev->dev, 1);
266
267 dev_info(&pdev->dev, "Atmel RTC for AT32AP700x at %08lx irq %ld\n",
268 (unsigned long)rtc->regs, rtc->irq);
269
270 return 0;
271
272out:
273 platform_set_drvdata(pdev, NULL);
274 return ret;
275}
276
277static int __exit at32_rtc_remove(struct platform_device *pdev)
278{
279 device_init_wakeup(&pdev->dev, 0);
280
281 platform_set_drvdata(pdev, NULL);
282
283 return 0;
284}
285
286MODULE_ALIAS("platform:at32ap700x_rtc");
287
288static struct platform_driver at32_rtc_driver = {
289 .remove = __exit_p(at32_rtc_remove),
290 .driver = {
291 .name = "at32ap700x_rtc",
292 .owner = THIS_MODULE,
293 },
294};
295
296module_platform_driver_probe(at32_rtc_driver, at32_rtc_probe);
297
298MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
299MODULE_DESCRIPTION("Real time clock for AVR32 AT32AP700x");
300MODULE_LICENSE("GPL");
301
