blackfin RTC driver: drop PIE/stopwatch code since the hardware can only do a max of 1HZ and this same functionality is provided by UIE
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-bfin.c b/drivers/rtc/rtc-bfin.c
index ceebce7..a1af4c2 100644
--- a/drivers/rtc/rtc-bfin.c
+++ b/drivers/rtc/rtc-bfin.c
@@ -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>
@@ -151,7 +160,6 @@
bfin_rtc_sync_pending(dev);
bfin_write_RTC_PREN(0x1);
bfin_write_RTC_ICTL(rtc_ictl);
- bfin_write_RTC_SWCNT(0);
bfin_write_RTC_ALARM(0);
bfin_write_RTC_ISTAT(0xFFFF);
rtc->rtc_wrote_regs = 0;
@@ -194,14 +202,6 @@
}
}
- 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);
@@ -361,33 +361,14 @@
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
}
-static int bfin_irq_set_state(struct device *dev, int enabled)
-{
- struct bfin_rtc *rtc = dev_get_drvdata(dev);
-
- dev_dbg_stamp(dev);
-
- bfin_rtc_sync_pending(dev);
-
- if (enabled) {
- bfin_rtc_int_set(RTC_ISTAT_STOPWATCH);
- bfin_write_RTC_SWCNT(rtc->rtc_dev->irq_freq);
- } else
- bfin_rtc_int_clear(~RTC_ISTAT_STOPWATCH);
-
- return 0;
-}
-
static struct rtc_class_ops bfin_rtc_ops = {
.open = bfin_rtc_open,
.release = bfin_rtc_release,
@@ -397,7 +378,6 @@
.read_alarm = bfin_rtc_read_alarm,
.set_alarm = bfin_rtc_set_alarm,
.proc = bfin_rtc_proc,
- .irq_set_state = bfin_irq_set_state,
};
static int __devinit bfin_rtc_probe(struct platform_device *pdev)
@@ -416,7 +396,9 @@
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);
