aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/rtc/rtc-bfin.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/rtc/rtc-bfin.c')
-rw-r--r--drivers/rtc/rtc-bfin.c105
1 files changed, 55 insertions, 50 deletions
diff --git a/drivers/rtc/rtc-bfin.c b/drivers/rtc/rtc-bfin.c
index 8624f55d0560..a1af4c27939b 100644
--- a/drivers/rtc/rtc-bfin.c
+++ b/drivers/rtc/rtc-bfin.c
@@ -2,7 +2,7 @@
* Blackfin On-Chip Real Time Clock Driver
* Supports BF52[257]/BF53[123]/BF53[467]/BF54[24789]
*
- * Copyright 2004-2007 Analog Devices Inc.
+ * Copyright 2004-2008 Analog Devices Inc.
*
* Enter bugs at http://blackfin.uclinux.org/
*
@@ -32,6 +32,15 @@
* writes to clear status registers complete immediately.
*/
+/* It may seem odd that there is no SWCNT code in here (which would be exposed
+ * via the periodic interrupt event, or PIE). Since the Blackfin RTC peripheral
+ * runs in units of seconds (N/HZ) but the Linux framework runs in units of HZ
+ * (2^N HZ), there is no point in keeping code that only provides 1 HZ PIEs.
+ * The same exact behavior can be accomplished by using the update interrupt
+ * event (UIE). Maybe down the line the RTC peripheral will suck less in which
+ * case we can re-introduce PIE support.
+ */
+
#include <linux/bcd.h>
#include <linux/completion.h>
#include <linux/delay.h>
@@ -144,14 +153,13 @@ static void bfin_rtc_sync_pending(struct device *dev)
* Initialize the RTC. Enable pre-scaler to scale RTC clock
* to 1Hz and clear interrupt/status registers.
*/
-static void bfin_rtc_reset(struct device *dev)
+static void bfin_rtc_reset(struct device *dev, u16 rtc_ictl)
{
struct bfin_rtc *rtc = dev_get_drvdata(dev);
dev_dbg_stamp(dev);
bfin_rtc_sync_pending(dev);
bfin_write_RTC_PREN(0x1);
- bfin_write_RTC_ICTL(RTC_ISTAT_WRITE_COMPLETE);
- bfin_write_RTC_SWCNT(0);
+ bfin_write_RTC_ICTL(rtc_ictl);
bfin_write_RTC_ALARM(0);
bfin_write_RTC_ISTAT(0xFFFF);
rtc->rtc_wrote_regs = 0;
@@ -194,14 +202,6 @@ static irqreturn_t bfin_rtc_interrupt(int irq, void *dev_id)
}
}
- if (rtc_ictl & RTC_ISTAT_STOPWATCH) {
- if (rtc_istat & RTC_ISTAT_STOPWATCH) {
- bfin_write_RTC_ISTAT(RTC_ISTAT_STOPWATCH);
- events |= RTC_PF | RTC_IRQF;
- bfin_write_RTC_SWCNT(rtc->rtc_dev->irq_freq);
- }
- }
-
if (rtc_ictl & RTC_ISTAT_SEC) {
if (rtc_istat & RTC_ISTAT_SEC) {
bfin_write_RTC_ISTAT(RTC_ISTAT_SEC);
@@ -226,7 +226,7 @@ static int bfin_rtc_open(struct device *dev)
ret = request_irq(IRQ_RTC, bfin_rtc_interrupt, IRQF_SHARED, to_platform_device(dev)->name, dev);
if (!ret)
- bfin_rtc_reset(dev);
+ bfin_rtc_reset(dev, RTC_ISTAT_WRITE_COMPLETE);
return ret;
}
@@ -234,16 +234,16 @@ static int bfin_rtc_open(struct device *dev)
static void bfin_rtc_release(struct device *dev)
{
dev_dbg_stamp(dev);
- bfin_rtc_reset(dev);
+ bfin_rtc_reset(dev, 0);
free_irq(IRQ_RTC, dev);
}
-static void bfin_rtc_int_set(struct bfin_rtc *rtc, u16 rtc_int)
+static void bfin_rtc_int_set(u16 rtc_int)
{
bfin_write_RTC_ISTAT(rtc_int);
bfin_write_RTC_ICTL(bfin_read_RTC_ICTL() | rtc_int);
}
-static void bfin_rtc_int_clear(struct bfin_rtc *rtc, u16 rtc_int)
+static void bfin_rtc_int_clear(u16 rtc_int)
{
bfin_write_RTC_ICTL(bfin_read_RTC_ICTL() & rtc_int);
}
@@ -252,7 +252,7 @@ static void bfin_rtc_int_set_alarm(struct bfin_rtc *rtc)
/* Blackfin has different bits for whether the alarm is
* more than 24 hours away.
*/
- bfin_rtc_int_set(rtc, (rtc->rtc_alarm.tm_yday == -1 ? RTC_ISTAT_ALARM : RTC_ISTAT_ALARM_DAY));
+ bfin_rtc_int_set(rtc->rtc_alarm.tm_yday == -1 ? RTC_ISTAT_ALARM : RTC_ISTAT_ALARM_DAY);
}
static int bfin_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
@@ -264,23 +264,13 @@ static int bfin_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long ar
bfin_rtc_sync_pending(dev);
switch (cmd) {
- case RTC_PIE_ON:
- dev_dbg_stamp(dev);
- bfin_rtc_int_set(rtc, RTC_ISTAT_STOPWATCH);
- bfin_write_RTC_SWCNT(rtc->rtc_dev->irq_freq);
- break;
- case RTC_PIE_OFF:
- dev_dbg_stamp(dev);
- bfin_rtc_int_clear(rtc, ~RTC_ISTAT_STOPWATCH);
- break;
-
case RTC_UIE_ON:
dev_dbg_stamp(dev);
- bfin_rtc_int_set(rtc, RTC_ISTAT_SEC);
+ bfin_rtc_int_set(RTC_ISTAT_SEC);
break;
case RTC_UIE_OFF:
dev_dbg_stamp(dev);
- bfin_rtc_int_clear(rtc, ~RTC_ISTAT_SEC);
+ bfin_rtc_int_clear(~RTC_ISTAT_SEC);
break;
case RTC_AIE_ON:
@@ -289,7 +279,7 @@ static int bfin_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long ar
break;
case RTC_AIE_OFF:
dev_dbg_stamp(dev);
- bfin_rtc_int_clear(rtc, ~(RTC_ISTAT_ALARM | RTC_ISTAT_ALARM_DAY));
+ bfin_rtc_int_clear(~(RTC_ISTAT_ALARM | RTC_ISTAT_ALARM_DAY));
break;
default:
@@ -371,30 +361,14 @@ static int bfin_rtc_proc(struct device *dev, struct seq_file *seq)
seq_printf(seq,
"alarm_IRQ\t: %s\n"
"wkalarm_IRQ\t: %s\n"
- "seconds_IRQ\t: %s\n"
- "periodic_IRQ\t: %s\n",
+ "seconds_IRQ\t: %s\n",
yesno(ictl & RTC_ISTAT_ALARM),
yesno(ictl & RTC_ISTAT_ALARM_DAY),
- yesno(ictl & RTC_ISTAT_SEC),
- yesno(ictl & RTC_ISTAT_STOPWATCH));
+ yesno(ictl & RTC_ISTAT_SEC));
return 0;
#undef yesno
}
-/**
- * bfin_irq_set_freq - make sure hardware supports requested freq
- * @dev: pointer to RTC device structure
- * @freq: requested frequency rate
- *
- * The Blackfin RTC can only generate periodic events at 1 per
- * second (1 Hz), so reject any attempt at changing it.
- */
-static int bfin_irq_set_freq(struct device *dev, int freq)
-{
- dev_dbg_stamp(dev);
- return -ENOTTY;
-}
-
static struct rtc_class_ops bfin_rtc_ops = {
.open = bfin_rtc_open,
.release = bfin_rtc_release,
@@ -404,7 +378,6 @@ static struct rtc_class_ops bfin_rtc_ops = {
.read_alarm = bfin_rtc_read_alarm,
.set_alarm = bfin_rtc_set_alarm,
.proc = bfin_rtc_proc,
- .irq_set_freq = bfin_irq_set_freq,
};
static int __devinit bfin_rtc_probe(struct platform_device *pdev)
@@ -423,10 +396,14 @@ static int __devinit bfin_rtc_probe(struct platform_device *pdev)
ret = PTR_ERR(rtc->rtc_dev);
goto err;
}
- rtc->rtc_dev->irq_freq = 1;
+
+ /* see comment at top of file about stopwatch/PIE */
+ bfin_write_RTC_SWCNT(0);
platform_set_drvdata(pdev, rtc);
+ device_init_wakeup(&pdev->dev, 1);
+
return 0;
err:
@@ -445,6 +422,32 @@ static int __devexit bfin_rtc_remove(struct platform_device *pdev)
return 0;
}
+#ifdef CONFIG_PM
+static int bfin_rtc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ if (device_may_wakeup(&pdev->dev)) {
+ enable_irq_wake(IRQ_RTC);
+ bfin_rtc_sync_pending(&pdev->dev);
+ } else
+ bfin_rtc_int_clear(-1);
+
+ return 0;
+}
+
+static int bfin_rtc_resume(struct platform_device *pdev)
+{
+ if (device_may_wakeup(&pdev->dev))
+ disable_irq_wake(IRQ_RTC);
+ else
+ bfin_write_RTC_ISTAT(-1);
+
+ return 0;
+}
+#else
+# define bfin_rtc_suspend NULL
+# define bfin_rtc_resume NULL
+#endif
+
static struct platform_driver bfin_rtc_driver = {
.driver = {
.name = "rtc-bfin",
@@ -452,6 +455,8 @@ static struct platform_driver bfin_rtc_driver = {
},
.probe = bfin_rtc_probe,
.remove = __devexit_p(bfin_rtc_remove),
+ .suspend = bfin_rtc_suspend,
+ .resume = bfin_rtc_resume,
};
static int __init bfin_rtc_init(void)
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.