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Message-Id: <1364982862-19759-1-git-send-email-jhovold@gmail.com>
Date: Wed, 3 Apr 2013 11:54:22 +0200
From: Johan Hovold <jhovold@...il.com>
To: Nicolas Ferre <nicolas.ferre@...el.com>
Cc: Douglas Gilbert <dgilbert@...erlog.com>,
Jean-Christophe PLAGNIOL-VILLARD <plagnioj@...osoft.com>,
Ludovic Desroches <ludovic.desroches@...el.com>,
linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
Johan Hovold <jhovold@...il.com>,
stable <stable@...r.kernel.org>
Subject: [PATCH] Revert "drivers/rtc/rtc-at91rm9200.c: use a variable for storing IMR"
This reverts commit 0ef1594c017521ea89278e80fe3f80dafb17abde.
This patch introduced a few races which cannot be easily fixed with a
small follow-up patch. Furthermore, the SoC with the broken hardware
register, which this patch intended to add support for, can only be used
with device trees, which this driver currently does not support.
Cc: stable <stable@...r.kernel.org>
Signed-off-by: Johan Hovold <jhovold@...il.com>
---
drivers/rtc/rtc-at91rm9200.c | 50 +++++++++++++++++---------------------------
drivers/rtc/rtc-at91rm9200.h | 1 +
2 files changed, 20 insertions(+), 31 deletions(-)
diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c
index 0a9f27e..434ebc3 100644
--- a/drivers/rtc/rtc-at91rm9200.c
+++ b/drivers/rtc/rtc-at91rm9200.c
@@ -44,7 +44,6 @@ static DECLARE_COMPLETION(at91_rtc_updated);
static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
static void __iomem *at91_rtc_regs;
static int irq;
-static u32 at91_rtc_imr;
/*
* Decode time/date into rtc_time structure
@@ -109,11 +108,9 @@ static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
cr = at91_rtc_read(AT91_RTC_CR);
at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
- at91_rtc_imr |= AT91_RTC_ACKUPD;
at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
- at91_rtc_imr &= ~AT91_RTC_ACKUPD;
at91_rtc_write(AT91_RTC_TIMR,
bin2bcd(tm->tm_sec) << 0
@@ -145,7 +142,7 @@ static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
tm->tm_year = at91_alarm_year - 1900;
- alrm->enabled = (at91_rtc_imr & AT91_RTC_ALARM)
+ alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
? 1 : 0;
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
@@ -171,7 +168,6 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
tm.tm_sec = alrm->time.tm_sec;
at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
- at91_rtc_imr &= ~AT91_RTC_ALARM;
at91_rtc_write(AT91_RTC_TIMALR,
bin2bcd(tm.tm_sec) << 0
| bin2bcd(tm.tm_min) << 8
@@ -184,7 +180,6 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
if (alrm->enabled) {
at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
- at91_rtc_imr |= AT91_RTC_ALARM;
at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
}
@@ -201,12 +196,9 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
if (enabled) {
at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
- at91_rtc_imr |= AT91_RTC_ALARM;
at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
- } else {
+ } else
at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
- at91_rtc_imr &= ~AT91_RTC_ALARM;
- }
return 0;
}
@@ -215,10 +207,12 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
*/
static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
{
+ unsigned long imr = at91_rtc_read(AT91_RTC_IMR);
+
seq_printf(seq, "update_IRQ\t: %s\n",
- (at91_rtc_imr & AT91_RTC_ACKUPD) ? "yes" : "no");
+ (imr & AT91_RTC_ACKUPD) ? "yes" : "no");
seq_printf(seq, "periodic_IRQ\t: %s\n",
- (at91_rtc_imr & AT91_RTC_SECEV) ? "yes" : "no");
+ (imr & AT91_RTC_SECEV) ? "yes" : "no");
return 0;
}
@@ -233,7 +227,7 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
unsigned int rtsr;
unsigned long events = 0;
- rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_imr;
+ rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR);
if (rtsr) { /* this interrupt is shared! Is it ours? */
if (rtsr & AT91_RTC_ALARM)
events |= (RTC_AF | RTC_IRQF);
@@ -297,7 +291,6 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
AT91_RTC_SECEV | AT91_RTC_TIMEV |
AT91_RTC_CALEV);
- at91_rtc_imr = 0;
ret = request_irq(irq, at91_rtc_interrupt,
IRQF_SHARED,
@@ -336,7 +329,6 @@ static int __exit at91_rtc_remove(struct platform_device *pdev)
at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
AT91_RTC_SECEV | AT91_RTC_TIMEV |
AT91_RTC_CALEV);
- at91_rtc_imr = 0;
free_irq(irq, pdev);
rtc_device_unregister(rtc);
@@ -349,35 +341,31 @@ static int __exit at91_rtc_remove(struct platform_device *pdev)
/* AT91RM9200 RTC Power management control */
-static u32 at91_rtc_bkpimr;
-
+static u32 at91_rtc_imr;
static int at91_rtc_suspend(struct device *dev)
{
/* this IRQ is shared with DBGU and other hardware which isn't
* necessarily doing PM like we are...
*/
- at91_rtc_bkpimr = at91_rtc_imr & (AT91_RTC_ALARM|AT91_RTC_SECEV);
- if (at91_rtc_bkpimr) {
- if (device_may_wakeup(dev)) {
+ at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR)
+ & (AT91_RTC_ALARM|AT91_RTC_SECEV);
+ if (at91_rtc_imr) {
+ if (device_may_wakeup(dev))
enable_irq_wake(irq);
- } else {
- at91_rtc_write(AT91_RTC_IDR, at91_rtc_bkpimr);
- at91_rtc_imr &= ~at91_rtc_bkpimr;
- }
-}
+ else
+ at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr);
+ }
return 0;
}
static int at91_rtc_resume(struct device *dev)
{
- if (at91_rtc_bkpimr) {
- if (device_may_wakeup(dev)) {
+ if (at91_rtc_imr) {
+ if (device_may_wakeup(dev))
disable_irq_wake(irq);
- } else {
- at91_rtc_imr |= at91_rtc_bkpimr;
- at91_rtc_write(AT91_RTC_IER, at91_rtc_bkpimr);
- }
+ else
+ at91_rtc_write(AT91_RTC_IER, at91_rtc_imr);
}
return 0;
}
diff --git a/drivers/rtc/rtc-at91rm9200.h b/drivers/rtc/rtc-at91rm9200.h
index 5f940b6..da1945e 100644
--- a/drivers/rtc/rtc-at91rm9200.h
+++ b/drivers/rtc/rtc-at91rm9200.h
@@ -64,6 +64,7 @@
#define AT91_RTC_SCCR 0x1c /* Status Clear Command Register */
#define AT91_RTC_IER 0x20 /* Interrupt Enable Register */
#define AT91_RTC_IDR 0x24 /* Interrupt Disable Register */
+#define AT91_RTC_IMR 0x28 /* Interrupt Mask Register */
#define AT91_RTC_VER 0x2c /* Valid Entry Register */
#define AT91_RTC_NVTIM (1 << 0) /* Non valid Time */
--
1.8.1.5
--
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