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23#include <linux/device.h>
24#include <linux/err.h>
25#include <linux/init.h>
26#include <linux/kernel.h>
27#include <linux/mfd/tps6586x.h>
28#include <linux/module.h>
29#include <linux/platform_device.h>
30#include <linux/pm_runtime.h>
31#include <linux/rtc.h>
32#include <linux/slab.h>
33
34#define RTC_CTRL 0xc0
35#define POR_RESET_N BIT(7)
36#define OSC_SRC_SEL BIT(6)
37#define RTC_ENABLE BIT(5)
38#define RTC_BUF_ENABLE BIT(4)
39#define PRE_BYPASS BIT(3)
40#define CL_SEL_MASK (BIT(2)|BIT(1))
41#define CL_SEL_POS 1
42#define RTC_ALARM1_HI 0xc1
43#define RTC_COUNT4 0xc6
44
45
46#define RTC_COUNT4_DUMMYREAD 0xc5
47
48
49#define ALM1_VALID_RANGE_IN_SEC 0x3FFF
50
51#define TPS6586X_RTC_CL_SEL_1_5PF 0x0
52#define TPS6586X_RTC_CL_SEL_6_5PF 0x1
53#define TPS6586X_RTC_CL_SEL_7_5PF 0x2
54#define TPS6586X_RTC_CL_SEL_12_5PF 0x3
55
56struct tps6586x_rtc {
57 struct device *dev;
58 struct rtc_device *rtc;
59 int irq;
60 bool irq_en;
61 unsigned long long epoch_start;
62};
63
64static inline struct device *to_tps6586x_dev(struct device *dev)
65{
66 return dev->parent;
67}
68
69static int tps6586x_rtc_read_time(struct device *dev, struct rtc_time *tm)
70{
71 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
72 struct device *tps_dev = to_tps6586x_dev(dev);
73 unsigned long long ticks = 0;
74 unsigned long seconds;
75 u8 buff[6];
76 int ret;
77 int i;
78
79 ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD, sizeof(buff), buff);
80 if (ret < 0) {
81 dev_err(dev, "read counter failed with err %d\n", ret);
82 return ret;
83 }
84
85 for (i = 1; i < sizeof(buff); i++) {
86 ticks <<= 8;
87 ticks |= buff[i];
88 }
89
90 seconds = ticks >> 10;
91 seconds += rtc->epoch_start;
92 rtc_time_to_tm(seconds, tm);
93 return rtc_valid_tm(tm);
94}
95
96static int tps6586x_rtc_set_time(struct device *dev, struct rtc_time *tm)
97{
98 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
99 struct device *tps_dev = to_tps6586x_dev(dev);
100 unsigned long long ticks;
101 unsigned long seconds;
102 u8 buff[5];
103 int ret;
104
105 rtc_tm_to_time(tm, &seconds);
106 if (seconds < rtc->epoch_start) {
107 dev_err(dev, "requested time unsupported\n");
108 return -EINVAL;
109 }
110 seconds -= rtc->epoch_start;
111
112 ticks = (unsigned long long)seconds << 10;
113 buff[0] = (ticks >> 32) & 0xff;
114 buff[1] = (ticks >> 24) & 0xff;
115 buff[2] = (ticks >> 16) & 0xff;
116 buff[3] = (ticks >> 8) & 0xff;
117 buff[4] = ticks & 0xff;
118
119
120 ret = tps6586x_clr_bits(tps_dev, RTC_CTRL, RTC_ENABLE);
121 if (ret < 0) {
122 dev_err(dev, "failed to clear RTC_ENABLE\n");
123 return ret;
124 }
125
126 ret = tps6586x_writes(tps_dev, RTC_COUNT4, sizeof(buff), buff);
127 if (ret < 0) {
128 dev_err(dev, "failed to program new time\n");
129 return ret;
130 }
131
132
133 ret = tps6586x_set_bits(tps_dev, RTC_CTRL, RTC_ENABLE);
134 if (ret < 0) {
135 dev_err(dev, "failed to set RTC_ENABLE\n");
136 return ret;
137 }
138 return 0;
139}
140
141static int tps6586x_rtc_alarm_irq_enable(struct device *dev,
142 unsigned int enabled)
143{
144 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
145
146 if (enabled && !rtc->irq_en) {
147 enable_irq(rtc->irq);
148 rtc->irq_en = true;
149 } else if (!enabled && rtc->irq_en) {
150 disable_irq(rtc->irq);
151 rtc->irq_en = false;
152 }
153 return 0;
154}
155
156static int tps6586x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
157{
158 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
159 struct device *tps_dev = to_tps6586x_dev(dev);
160 unsigned long seconds;
161 unsigned long ticks;
162 unsigned long rtc_current_time;
163 unsigned long long rticks = 0;
164 u8 buff[3];
165 u8 rbuff[6];
166 int ret;
167 int i;
168
169 rtc_tm_to_time(&alrm->time, &seconds);
170
171 if (alrm->enabled && (seconds < rtc->epoch_start)) {
172 dev_err(dev, "can't set alarm to requested time\n");
173 return -EINVAL;
174 }
175
176 ret = tps6586x_rtc_alarm_irq_enable(dev, alrm->enabled);
177 if (ret < 0) {
178 dev_err(dev, "can't set alarm irq, err %d\n", ret);
179 return ret;
180 }
181
182 seconds -= rtc->epoch_start;
183 ret = tps6586x_reads(tps_dev, RTC_COUNT4_DUMMYREAD,
184 sizeof(rbuff), rbuff);
185 if (ret < 0) {
186 dev_err(dev, "read counter failed with err %d\n", ret);
187 return ret;
188 }
189
190 for (i = 1; i < sizeof(rbuff); i++) {
191 rticks <<= 8;
192 rticks |= rbuff[i];
193 }
194
195 rtc_current_time = rticks >> 10;
196 if ((seconds - rtc_current_time) > ALM1_VALID_RANGE_IN_SEC)
197 seconds = rtc_current_time - 1;
198
199 ticks = (unsigned long long)seconds << 10;
200 buff[0] = (ticks >> 16) & 0xff;
201 buff[1] = (ticks >> 8) & 0xff;
202 buff[2] = ticks & 0xff;
203
204 ret = tps6586x_writes(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff);
205 if (ret)
206 dev_err(dev, "programming alarm failed with err %d\n", ret);
207
208 return ret;
209}
210
211static int tps6586x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
212{
213 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
214 struct device *tps_dev = to_tps6586x_dev(dev);
215 unsigned long ticks;
216 unsigned long seconds;
217 u8 buff[3];
218 int ret;
219
220 ret = tps6586x_reads(tps_dev, RTC_ALARM1_HI, sizeof(buff), buff);
221 if (ret) {
222 dev_err(dev, "read RTC_ALARM1_HI failed with err %d\n", ret);
223 return ret;
224 }
225
226 ticks = (buff[0] << 16) | (buff[1] << 8) | buff[2];
227 seconds = ticks >> 10;
228 seconds += rtc->epoch_start;
229
230 rtc_time_to_tm(seconds, &alrm->time);
231 return 0;
232}
233
234static const struct rtc_class_ops tps6586x_rtc_ops = {
235 .read_time = tps6586x_rtc_read_time,
236 .set_time = tps6586x_rtc_set_time,
237 .set_alarm = tps6586x_rtc_set_alarm,
238 .read_alarm = tps6586x_rtc_read_alarm,
239 .alarm_irq_enable = tps6586x_rtc_alarm_irq_enable,
240};
241
242static irqreturn_t tps6586x_rtc_irq(int irq, void *data)
243{
244 struct tps6586x_rtc *rtc = data;
245
246 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
247 return IRQ_HANDLED;
248}
249
250static int tps6586x_rtc_probe(struct platform_device *pdev)
251{
252 struct device *tps_dev = to_tps6586x_dev(&pdev->dev);
253 struct tps6586x_rtc *rtc;
254 int ret;
255
256 rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
257 if (!rtc)
258 return -ENOMEM;
259
260 rtc->dev = &pdev->dev;
261 rtc->irq = platform_get_irq(pdev, 0);
262
263
264 rtc->epoch_start = mktime(2009, 1, 1, 0, 0, 0);
265
266
267 ret = tps6586x_update(tps_dev, RTC_CTRL,
268 RTC_ENABLE | OSC_SRC_SEL |
269 ((TPS6586X_RTC_CL_SEL_1_5PF << CL_SEL_POS) & CL_SEL_MASK),
270 RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK);
271 if (ret < 0) {
272 dev_err(&pdev->dev, "unable to start counter\n");
273 return ret;
274 }
275
276 device_init_wakeup(&pdev->dev, 1);
277
278 platform_set_drvdata(pdev, rtc);
279 rtc->rtc = devm_rtc_device_register(&pdev->dev, dev_name(&pdev->dev),
280 &tps6586x_rtc_ops, THIS_MODULE);
281 if (IS_ERR(rtc->rtc)) {
282 ret = PTR_ERR(rtc->rtc);
283 dev_err(&pdev->dev, "RTC device register: ret %d\n", ret);
284 goto fail_rtc_register;
285 }
286
287 ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
288 tps6586x_rtc_irq,
289 IRQF_ONESHOT,
290 dev_name(&pdev->dev), rtc);
291 if (ret < 0) {
292 dev_err(&pdev->dev, "request IRQ(%d) failed with ret %d\n",
293 rtc->irq, ret);
294 goto fail_rtc_register;
295 }
296 disable_irq(rtc->irq);
297 return 0;
298
299fail_rtc_register:
300 tps6586x_update(tps_dev, RTC_CTRL, 0,
301 RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK);
302 return ret;
303};
304
305static int tps6586x_rtc_remove(struct platform_device *pdev)
306{
307 struct device *tps_dev = to_tps6586x_dev(&pdev->dev);
308
309 tps6586x_update(tps_dev, RTC_CTRL, 0,
310 RTC_ENABLE | OSC_SRC_SEL | PRE_BYPASS | CL_SEL_MASK);
311 return 0;
312}
313
314#ifdef CONFIG_PM_SLEEP
315static int tps6586x_rtc_suspend(struct device *dev)
316{
317 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
318
319 if (device_may_wakeup(dev))
320 enable_irq_wake(rtc->irq);
321 return 0;
322}
323
324static int tps6586x_rtc_resume(struct device *dev)
325{
326 struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
327
328 if (device_may_wakeup(dev))
329 disable_irq_wake(rtc->irq);
330 return 0;
331}
332#endif
333
334static SIMPLE_DEV_PM_OPS(tps6586x_pm_ops, tps6586x_rtc_suspend,
335 tps6586x_rtc_resume);
336
337static struct platform_driver tps6586x_rtc_driver = {
338 .driver = {
339 .name = "tps6586x-rtc",
340 .pm = &tps6586x_pm_ops,
341 },
342 .probe = tps6586x_rtc_probe,
343 .remove = tps6586x_rtc_remove,
344};
345module_platform_driver(tps6586x_rtc_driver);
346
347MODULE_ALIAS("platform:rtc-tps6586x");
348MODULE_DESCRIPTION("TI TPS6586x RTC driver");
349MODULE_AUTHOR("Laxman dewangan <ldewangan@nvidia.com>");
350MODULE_LICENSE("GPL v2");
351
