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20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/io.h>
23#include <linux/init.h>
24#include <linux/platform_device.h>
25#include <linux/interrupt.h>
26#include <linux/delay.h>
27#include <linux/rtc.h>
28#include <linux/slab.h>
29#include <linux/of_device.h>
30#include <linux/of.h>
31#include <linux/stmp_device.h>
32#include <linux/stmp3xxx_rtc_wdt.h>
33
34#define STMP3XXX_RTC_CTRL 0x0
35#define STMP3XXX_RTC_CTRL_SET 0x4
36#define STMP3XXX_RTC_CTRL_CLR 0x8
37#define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001
38#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002
39#define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004
40#define STMP3XXX_RTC_CTRL_WATCHDOGEN 0x00000010
41
42#define STMP3XXX_RTC_STAT 0x10
43#define STMP3XXX_RTC_STAT_STALE_SHIFT 16
44#define STMP3XXX_RTC_STAT_RTC_PRESENT 0x80000000
45
46#define STMP3XXX_RTC_SECONDS 0x30
47
48#define STMP3XXX_RTC_ALARM 0x40
49
50#define STMP3XXX_RTC_WATCHDOG 0x50
51
52#define STMP3XXX_RTC_PERSISTENT0 0x60
53#define STMP3XXX_RTC_PERSISTENT0_SET 0x64
54#define STMP3XXX_RTC_PERSISTENT0_CLR 0x68
55#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN 0x00000002
56#define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004
57#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080
58
59#define STMP3XXX_RTC_PERSISTENT1 0x70
60
61#define STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER 0x80000000
62
63struct stmp3xxx_rtc_data {
64 struct rtc_device *rtc;
65 void __iomem *io;
66 int irq_alarm;
67};
68
69#if IS_ENABLED(CONFIG_STMP3XXX_RTC_WATCHDOG)
70
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83
84static void stmp3xxx_wdt_set_timeout(struct device *dev, u32 timeout)
85{
86 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
87
88 if (timeout) {
89 writel(timeout, rtc_data->io + STMP3XXX_RTC_WATCHDOG);
90 writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
91 rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_SET);
92 writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
93 rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_SET);
94 } else {
95 writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
96 rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_CLR);
97 writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
98 rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_CLR);
99 }
100}
101
102static struct stmp3xxx_wdt_pdata wdt_pdata = {
103 .wdt_set_timeout = stmp3xxx_wdt_set_timeout,
104};
105
106static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
107{
108 struct platform_device *wdt_pdev =
109 platform_device_alloc("stmp3xxx_rtc_wdt", rtc_pdev->id);
110
111 if (wdt_pdev) {
112 wdt_pdev->dev.parent = &rtc_pdev->dev;
113 wdt_pdev->dev.platform_data = &wdt_pdata;
114 platform_device_add(wdt_pdev);
115 }
116}
117#else
118static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
119{
120}
121#endif
122
123static int stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
124{
125 int timeout = 5000;
126
127
128
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130
131
132
133
134
135
136 do {
137 if (!(readl(rtc_data->io + STMP3XXX_RTC_STAT) &
138 (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)))
139 return 0;
140 udelay(1);
141 } while (--timeout > 0);
142 return (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
143 (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) ? -ETIME : 0;
144}
145
146
147static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
148{
149 int ret;
150 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
151
152 ret = stmp3xxx_wait_time(rtc_data);
153 if (ret)
154 return ret;
155
156 rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm);
157 return 0;
158}
159
160static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
161{
162 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
163
164 writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS);
165 return stmp3xxx_wait_time(rtc_data);
166}
167
168
169static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
170{
171 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
172 u32 status = readl(rtc_data->io + STMP3XXX_RTC_CTRL);
173
174 if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) {
175 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ,
176 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
177 rtc_update_irq(rtc_data->rtc, 1, RTC_AF | RTC_IRQF);
178 return IRQ_HANDLED;
179 }
180
181 return IRQ_NONE;
182}
183
184static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
185{
186 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
187
188 if (enabled) {
189 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
190 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
191 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
192 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
193 rtc_data->io + STMP3XXX_RTC_CTRL_SET);
194 } else {
195 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
196 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
197 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
198 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
199 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
200 }
201 return 0;
202}
203
204static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
205{
206 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
207
208 rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_ALARM), &alm->time);
209 return 0;
210}
211
212static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
213{
214 unsigned long t;
215 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
216
217 rtc_tm_to_time(&alm->time, &t);
218 writel(t, rtc_data->io + STMP3XXX_RTC_ALARM);
219
220 stmp3xxx_alarm_irq_enable(dev, alm->enabled);
221
222 return 0;
223}
224
225static struct rtc_class_ops stmp3xxx_rtc_ops = {
226 .alarm_irq_enable =
227 stmp3xxx_alarm_irq_enable,
228 .read_time = stmp3xxx_rtc_gettime,
229 .set_mmss = stmp3xxx_rtc_set_mmss,
230 .read_alarm = stmp3xxx_rtc_read_alarm,
231 .set_alarm = stmp3xxx_rtc_set_alarm,
232};
233
234static int stmp3xxx_rtc_remove(struct platform_device *pdev)
235{
236 struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);
237
238 if (!rtc_data)
239 return 0;
240
241 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
242 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
243
244 return 0;
245}
246
247static int stmp3xxx_rtc_probe(struct platform_device *pdev)
248{
249 struct stmp3xxx_rtc_data *rtc_data;
250 struct resource *r;
251 int err;
252
253 rtc_data = devm_kzalloc(&pdev->dev, sizeof(*rtc_data), GFP_KERNEL);
254 if (!rtc_data)
255 return -ENOMEM;
256
257 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
258 if (!r) {
259 dev_err(&pdev->dev, "failed to get resource\n");
260 return -ENXIO;
261 }
262
263 rtc_data->io = devm_ioremap(&pdev->dev, r->start, resource_size(r));
264 if (!rtc_data->io) {
265 dev_err(&pdev->dev, "ioremap failed\n");
266 return -EIO;
267 }
268
269 rtc_data->irq_alarm = platform_get_irq(pdev, 0);
270
271 if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) &
272 STMP3XXX_RTC_STAT_RTC_PRESENT)) {
273 dev_err(&pdev->dev, "no device onboard\n");
274 return -ENODEV;
275 }
276
277 platform_set_drvdata(pdev, rtc_data);
278
279 err = stmp_reset_block(rtc_data->io);
280 if (err) {
281 dev_err(&pdev->dev, "stmp_reset_block failed: %d\n", err);
282 return err;
283 }
284
285 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
286 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
287 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
288 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
289
290 writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN |
291 STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
292 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
293
294 rtc_data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
295 &stmp3xxx_rtc_ops, THIS_MODULE);
296 if (IS_ERR(rtc_data->rtc))
297 return PTR_ERR(rtc_data->rtc);
298
299 err = devm_request_irq(&pdev->dev, rtc_data->irq_alarm,
300 stmp3xxx_rtc_interrupt, 0, "RTC alarm", &pdev->dev);
301 if (err) {
302 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
303 rtc_data->irq_alarm);
304 return err;
305 }
306
307 stmp3xxx_wdt_register(pdev);
308 return 0;
309}
310
311#ifdef CONFIG_PM_SLEEP
312static int stmp3xxx_rtc_suspend(struct device *dev)
313{
314 return 0;
315}
316
317static int stmp3xxx_rtc_resume(struct device *dev)
318{
319 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
320
321 stmp_reset_block(rtc_data->io);
322 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
323 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
324 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
325 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
326 return 0;
327}
328#endif
329
330static SIMPLE_DEV_PM_OPS(stmp3xxx_rtc_pm_ops, stmp3xxx_rtc_suspend,
331 stmp3xxx_rtc_resume);
332
333static const struct of_device_id rtc_dt_ids[] = {
334 { .compatible = "fsl,stmp3xxx-rtc", },
335 { }
336};
337MODULE_DEVICE_TABLE(of, rtc_dt_ids);
338
339static struct platform_driver stmp3xxx_rtcdrv = {
340 .probe = stmp3xxx_rtc_probe,
341 .remove = stmp3xxx_rtc_remove,
342 .driver = {
343 .name = "stmp3xxx-rtc",
344 .owner = THIS_MODULE,
345 .pm = &stmp3xxx_rtc_pm_ops,
346 .of_match_table = rtc_dt_ids,
347 },
348};
349
350module_platform_driver(stmp3xxx_rtcdrv);
351
352MODULE_DESCRIPTION("STMP3xxx RTC Driver");
353MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com> and "
354 "Wolfram Sang <w.sang@pengutronix.de>");
355MODULE_LICENSE("GPL");
356
