aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-at91rm9200.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/rtc/rtc-at91rm9200.c')
-rw-r--r--drivers/rtc/rtc-at91rm9200.c131
1 files changed, 111 insertions, 20 deletions
diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c
index 0eab77b22340..f296f3f7db9b 100644
--- a/drivers/rtc/rtc-at91rm9200.c
+++ b/drivers/rtc/rtc-at91rm9200.c
@@ -25,6 +25,7 @@
25#include <linux/rtc.h> 25#include <linux/rtc.h>
26#include <linux/bcd.h> 26#include <linux/bcd.h>
27#include <linux/interrupt.h> 27#include <linux/interrupt.h>
28#include <linux/spinlock.h>
28#include <linux/ioctl.h> 29#include <linux/ioctl.h>
29#include <linux/completion.h> 30#include <linux/completion.h>
30#include <linux/io.h> 31#include <linux/io.h>
@@ -42,10 +43,65 @@
42 43
43#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */ 44#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
44 45
46struct at91_rtc_config {
47 bool use_shadow_imr;
48};
49
50static const struct at91_rtc_config *at91_rtc_config;
45static DECLARE_COMPLETION(at91_rtc_updated); 51static DECLARE_COMPLETION(at91_rtc_updated);
46static unsigned int at91_alarm_year = AT91_RTC_EPOCH; 52static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
47static void __iomem *at91_rtc_regs; 53static void __iomem *at91_rtc_regs;
48static int irq; 54static int irq;
55static DEFINE_SPINLOCK(at91_rtc_lock);
56static u32 at91_rtc_shadow_imr;
57
58static void at91_rtc_write_ier(u32 mask)
59{
60 unsigned long flags;
61
62 spin_lock_irqsave(&at91_rtc_lock, flags);
63 at91_rtc_shadow_imr |= mask;
64 at91_rtc_write(AT91_RTC_IER, mask);
65 spin_unlock_irqrestore(&at91_rtc_lock, flags);
66}
67
68static void at91_rtc_write_idr(u32 mask)
69{
70 unsigned long flags;
71
72 spin_lock_irqsave(&at91_rtc_lock, flags);
73 at91_rtc_write(AT91_RTC_IDR, mask);
74 /*
75 * Register read back (of any RTC-register) needed to make sure
76 * IDR-register write has reached the peripheral before updating
77 * shadow mask.
78 *
79 * Note that there is still a possibility that the mask is updated
80 * before interrupts have actually been disabled in hardware. The only
81 * way to be certain would be to poll the IMR-register, which is is
82 * the very register we are trying to emulate. The register read back
83 * is a reasonable heuristic.
84 */
85 at91_rtc_read(AT91_RTC_SR);
86 at91_rtc_shadow_imr &= ~mask;
87 spin_unlock_irqrestore(&at91_rtc_lock, flags);
88}
89
90static u32 at91_rtc_read_imr(void)
91{
92 unsigned long flags;
93 u32 mask;
94
95 if (at91_rtc_config->use_shadow_imr) {
96 spin_lock_irqsave(&at91_rtc_lock, flags);
97 mask = at91_rtc_shadow_imr;
98 spin_unlock_irqrestore(&at91_rtc_lock, flags);
99 } else {
100 mask = at91_rtc_read(AT91_RTC_IMR);
101 }
102
103 return mask;
104}
49 105
50/* 106/*
51 * Decode time/date into rtc_time structure 107 * Decode time/date into rtc_time structure
@@ -110,9 +166,9 @@ static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
110 cr = at91_rtc_read(AT91_RTC_CR); 166 cr = at91_rtc_read(AT91_RTC_CR);
111 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM); 167 at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
112 168
113 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD); 169 at91_rtc_write_ier(AT91_RTC_ACKUPD);
114 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */ 170 wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
115 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD); 171 at91_rtc_write_idr(AT91_RTC_ACKUPD);
116 172
117 at91_rtc_write(AT91_RTC_TIMR, 173 at91_rtc_write(AT91_RTC_TIMR,
118 bin2bcd(tm->tm_sec) << 0 174 bin2bcd(tm->tm_sec) << 0
@@ -144,7 +200,7 @@ static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
144 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); 200 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
145 tm->tm_year = at91_alarm_year - 1900; 201 tm->tm_year = at91_alarm_year - 1900;
146 202
147 alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM) 203 alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
148 ? 1 : 0; 204 ? 1 : 0;
149 205
150 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, 206 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
@@ -169,7 +225,7 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
169 tm.tm_min = alrm->time.tm_min; 225 tm.tm_min = alrm->time.tm_min;
170 tm.tm_sec = alrm->time.tm_sec; 226 tm.tm_sec = alrm->time.tm_sec;
171 227
172 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM); 228 at91_rtc_write_idr(AT91_RTC_ALARM);
173 at91_rtc_write(AT91_RTC_TIMALR, 229 at91_rtc_write(AT91_RTC_TIMALR,
174 bin2bcd(tm.tm_sec) << 0 230 bin2bcd(tm.tm_sec) << 0
175 | bin2bcd(tm.tm_min) << 8 231 | bin2bcd(tm.tm_min) << 8
@@ -182,7 +238,7 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
182 238
183 if (alrm->enabled) { 239 if (alrm->enabled) {
184 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); 240 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
185 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM); 241 at91_rtc_write_ier(AT91_RTC_ALARM);
186 } 242 }
187 243
188 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, 244 dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
@@ -198,9 +254,9 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
198 254
199 if (enabled) { 255 if (enabled) {
200 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); 256 at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
201 at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM); 257 at91_rtc_write_ier(AT91_RTC_ALARM);
202 } else 258 } else
203 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM); 259 at91_rtc_write_idr(AT91_RTC_ALARM);
204 260
205 return 0; 261 return 0;
206} 262}
@@ -209,7 +265,7 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
209 */ 265 */
210static int at91_rtc_proc(struct device *dev, struct seq_file *seq) 266static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
211{ 267{
212 unsigned long imr = at91_rtc_read(AT91_RTC_IMR); 268 unsigned long imr = at91_rtc_read_imr();
213 269
214 seq_printf(seq, "update_IRQ\t: %s\n", 270 seq_printf(seq, "update_IRQ\t: %s\n",
215 (imr & AT91_RTC_ACKUPD) ? "yes" : "no"); 271 (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
@@ -229,7 +285,7 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
229 unsigned int rtsr; 285 unsigned int rtsr;
230 unsigned long events = 0; 286 unsigned long events = 0;
231 287
232 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR); 288 rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
233 if (rtsr) { /* this interrupt is shared! Is it ours? */ 289 if (rtsr) { /* this interrupt is shared! Is it ours? */
234 if (rtsr & AT91_RTC_ALARM) 290 if (rtsr & AT91_RTC_ALARM)
235 events |= (RTC_AF | RTC_IRQF); 291 events |= (RTC_AF | RTC_IRQF);
@@ -250,6 +306,43 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
250 return IRQ_NONE; /* not handled */ 306 return IRQ_NONE; /* not handled */
251} 307}
252 308
309static const struct at91_rtc_config at91rm9200_config = {
310};
311
312static const struct at91_rtc_config at91sam9x5_config = {
313 .use_shadow_imr = true,
314};
315
316#ifdef CONFIG_OF
317static const struct of_device_id at91_rtc_dt_ids[] = {
318 {
319 .compatible = "atmel,at91rm9200-rtc",
320 .data = &at91rm9200_config,
321 }, {
322 .compatible = "atmel,at91sam9x5-rtc",
323 .data = &at91sam9x5_config,
324 }, {
325 /* sentinel */
326 }
327};
328MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
329#endif
330
331static const struct at91_rtc_config *
332at91_rtc_get_config(struct platform_device *pdev)
333{
334 const struct of_device_id *match;
335
336 if (pdev->dev.of_node) {
337 match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
338 if (!match)
339 return NULL;
340 return (const struct at91_rtc_config *)match->data;
341 }
342
343 return &at91rm9200_config;
344}
345
253static const struct rtc_class_ops at91_rtc_ops = { 346static const struct rtc_class_ops at91_rtc_ops = {
254 .read_time = at91_rtc_readtime, 347 .read_time = at91_rtc_readtime,
255 .set_time = at91_rtc_settime, 348 .set_time = at91_rtc_settime,
@@ -268,6 +361,10 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
268 struct resource *regs; 361 struct resource *regs;
269 int ret = 0; 362 int ret = 0;
270 363
364 at91_rtc_config = at91_rtc_get_config(pdev);
365 if (!at91_rtc_config)
366 return -ENODEV;
367
271 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); 368 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
272 if (!regs) { 369 if (!regs) {
273 dev_err(&pdev->dev, "no mmio resource defined\n"); 370 dev_err(&pdev->dev, "no mmio resource defined\n");
@@ -290,7 +387,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
290 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */ 387 at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
291 388
292 /* Disable all interrupts */ 389 /* Disable all interrupts */
293 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | 390 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
294 AT91_RTC_SECEV | AT91_RTC_TIMEV | 391 AT91_RTC_SECEV | AT91_RTC_TIMEV |
295 AT91_RTC_CALEV); 392 AT91_RTC_CALEV);
296 393
@@ -335,7 +432,7 @@ static int __exit at91_rtc_remove(struct platform_device *pdev)
335 struct rtc_device *rtc = platform_get_drvdata(pdev); 432 struct rtc_device *rtc = platform_get_drvdata(pdev);
336 433
337 /* Disable all interrupts */ 434 /* Disable all interrupts */
338 at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | 435 at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
339 AT91_RTC_SECEV | AT91_RTC_TIMEV | 436 AT91_RTC_SECEV | AT91_RTC_TIMEV |
340 AT91_RTC_CALEV); 437 AT91_RTC_CALEV);
341 free_irq(irq, pdev); 438 free_irq(irq, pdev);
@@ -358,13 +455,13 @@ static int at91_rtc_suspend(struct device *dev)
358 /* this IRQ is shared with DBGU and other hardware which isn't 455 /* this IRQ is shared with DBGU and other hardware which isn't
359 * necessarily doing PM like we are... 456 * necessarily doing PM like we are...
360 */ 457 */
361 at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR) 458 at91_rtc_imr = at91_rtc_read_imr()
362 & (AT91_RTC_ALARM|AT91_RTC_SECEV); 459 & (AT91_RTC_ALARM|AT91_RTC_SECEV);
363 if (at91_rtc_imr) { 460 if (at91_rtc_imr) {
364 if (device_may_wakeup(dev)) 461 if (device_may_wakeup(dev))
365 enable_irq_wake(irq); 462 enable_irq_wake(irq);
366 else 463 else
367 at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr); 464 at91_rtc_write_idr(at91_rtc_imr);
368 } 465 }
369 return 0; 466 return 0;
370} 467}
@@ -375,7 +472,7 @@ static int at91_rtc_resume(struct device *dev)
375 if (device_may_wakeup(dev)) 472 if (device_may_wakeup(dev))
376 disable_irq_wake(irq); 473 disable_irq_wake(irq);
377 else 474 else
378 at91_rtc_write(AT91_RTC_IER, at91_rtc_imr); 475 at91_rtc_write_ier(at91_rtc_imr);
379 } 476 }
380 return 0; 477 return 0;
381} 478}
@@ -383,12 +480,6 @@ static int at91_rtc_resume(struct device *dev)
383 480
384static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume); 481static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
385 482
386static const struct of_device_id at91_rtc_dt_ids[] = {
387 { .compatible = "atmel,at91rm9200-rtc" },
388 { /* sentinel */ }
389};
390MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
391
392static struct platform_driver at91_rtc_driver = { 483static struct platform_driver at91_rtc_driver = {
393 .remove = __exit_p(at91_rtc_remove), 484 .remove = __exit_p(at91_rtc_remove),
394 .driver = { 485 .driver = {