[PATCH 2/2] rtc: asm9260: rework locking

From: Alexandre Belloni
Date: Tue Aug 30 2016 - 20:19:33 EST


The rtc-asm9260 driver uses a discrete spinlock (wrongly uninitialized).
Use the rtc mutex to lock mmio accesses instead.

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
drivers/rtc/rtc-asm9260.c | 16 ++--------------
1 file changed, 2 insertions(+), 14 deletions(-)

diff --git a/drivers/rtc/rtc-asm9260.c b/drivers/rtc/rtc-asm9260.c
index 5219916ce11d..812f131da694 100644
--- a/drivers/rtc/rtc-asm9260.c
+++ b/drivers/rtc/rtc-asm9260.c
@@ -112,8 +112,6 @@ struct asm9260_rtc_priv {
void __iomem *iobase;
struct rtc_device *rtc;
struct clk *clk;
- /* io lock */
- spinlock_t lock;
};

static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
@@ -122,11 +120,13 @@ static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
u32 isr;
unsigned long events = 0;

+ mutex_lock(&priv->rtc->ops_lock);
isr = ioread32(priv->iobase + HW_CIIR);
if (!isr)
return IRQ_NONE;

iowrite32(0, priv->iobase + HW_CIIR);
+ mutex_unlock(&priv->rtc->ops_lock);

events |= RTC_AF | RTC_IRQF;

@@ -139,9 +139,7 @@ static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
u32 ctime0, ctime1, ctime2;
- unsigned long irq_flags;

- spin_lock_irqsave(&priv->lock, irq_flags);
ctime0 = ioread32(priv->iobase + HW_CTIME0);
ctime1 = ioread32(priv->iobase + HW_CTIME1);
ctime2 = ioread32(priv->iobase + HW_CTIME2);
@@ -155,7 +153,6 @@ static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
ctime1 = ioread32(priv->iobase + HW_CTIME1);
ctime2 = ioread32(priv->iobase + HW_CTIME2);
}
- spin_unlock_irqrestore(&priv->lock, irq_flags);

tm->tm_sec = (ctime0 >> BM_CTIME0_SEC_S) & BM_CTIME0_SEC_M;
tm->tm_min = (ctime0 >> BM_CTIME0_MIN_S) & BM_CTIME0_MIN_M;
@@ -174,9 +171,7 @@ static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
- unsigned long irq_flags;

- spin_lock_irqsave(&priv->lock, irq_flags);
/*
* make sure SEC counter will not flip other counter on write time,
* real value will be written at the enf of sequence.
@@ -191,7 +186,6 @@ static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
iowrite32(tm->tm_hour, priv->iobase + HW_HOUR);
iowrite32(tm->tm_min, priv->iobase + HW_MIN);
iowrite32(tm->tm_sec, priv->iobase + HW_SEC);
- spin_unlock_irqrestore(&priv->lock, irq_flags);

return 0;
}
@@ -199,9 +193,7 @@ static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
- unsigned long irq_flags;

- spin_lock_irqsave(&priv->lock, irq_flags);
alrm->time.tm_year = ioread32(priv->iobase + HW_ALYEAR);
alrm->time.tm_mon = ioread32(priv->iobase + HW_ALMON);
alrm->time.tm_mday = ioread32(priv->iobase + HW_ALDOM);
@@ -213,7 +205,6 @@ static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)

alrm->enabled = ioread32(priv->iobase + HW_AMR) ? 1 : 0;
alrm->pending = ioread32(priv->iobase + HW_CIIR) ? 1 : 0;
- spin_unlock_irqrestore(&priv->lock, irq_flags);

return rtc_valid_tm(&alrm->time);
}
@@ -221,9 +212,7 @@ static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
static int asm9260_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
- unsigned long irq_flags;

- spin_lock_irqsave(&priv->lock, irq_flags);
iowrite32(alrm->time.tm_year, priv->iobase + HW_ALYEAR);
iowrite32(alrm->time.tm_mon, priv->iobase + HW_ALMON);
iowrite32(alrm->time.tm_mday, priv->iobase + HW_ALDOM);
@@ -234,7 +223,6 @@ static int asm9260_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
iowrite32(alrm->time.tm_sec, priv->iobase + HW_ALSEC);

iowrite32(alrm->enabled ? 0 : BM_AMR_OFF, priv->iobase + HW_AMR);
- spin_unlock_irqrestore(&priv->lock, irq_flags);

return 0;
}
--
2.9.3