[PATCH][RESEND] rtc: rtc-s3c: Update RTC driver for supporting clockgating
From: Donggeun Kim
Date: Wed Jun 15 2011 - 04:43:27 EST
This patch supports clock gating.
Power consumption can be reduced by
setting rtc_clk disabled state except for when RTC related registers are accessed.
Signed-off-by: Donggeun Kim <dg77.kim@xxxxxxxxxxx>
Signed-off-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
Signed-off-by: KyungMin Park <kyungmin.park@xxxxxxxxxxx>
Resend to fix clock usage counter related error in s3c_rtc_remove function.
---
drivers/rtc/rtc-s3c.c | 27 ++++++++++++++++++++++++++-
1 files changed, 26 insertions(+), 1 deletions(-)
diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index 16512ec..53c99b1 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -57,11 +57,13 @@ static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
{
struct rtc_device *rdev = id;
+ clk_enable(rtc_clk);
rtc_update_irq(rdev, 1, RTC_AF | RTC_IRQF);
if (s3c_rtc_cpu_type == TYPE_S3C64XX)
writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
+ clk_disable(rtc_clk);
return IRQ_HANDLED;
}
@@ -69,11 +71,13 @@ static irqreturn_t s3c_rtc_tickirq(int irq, void *id)
{
struct rtc_device *rdev = id;
+ clk_enable(rtc_clk);
rtc_update_irq(rdev, 1, RTC_PF | RTC_IRQF);
if (s3c_rtc_cpu_type == TYPE_S3C64XX)
writeb(S3C2410_INTP_TIC, s3c_rtc_base + S3C2410_INTP);
+ clk_disable(rtc_clk);
return IRQ_HANDLED;
}
@@ -84,12 +88,14 @@ static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
pr_debug("%s: aie=%d\n", __func__, enabled);
+ clk_enable(rtc_clk);
tmp = readb(s3c_rtc_base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN;
if (enabled)
tmp |= S3C2410_RTCALM_ALMEN;
writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
+ clk_disable(rtc_clk);
return 0;
}
@@ -103,6 +109,7 @@ static int s3c_rtc_setfreq(struct device *dev, int freq)
if (!is_power_of_2(freq))
return -EINVAL;
+ clk_enable(rtc_clk);
spin_lock_irq(&s3c_rtc_pie_lock);
if (s3c_rtc_cpu_type == TYPE_S3C2410) {
@@ -114,6 +121,7 @@ static int s3c_rtc_setfreq(struct device *dev, int freq)
writel(tmp, s3c_rtc_base + S3C2410_TICNT);
spin_unlock_irq(&s3c_rtc_pie_lock);
+ clk_disable(rtc_clk);
return 0;
}
@@ -125,6 +133,7 @@ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
unsigned int have_retried = 0;
void __iomem *base = s3c_rtc_base;
+ clk_enable(rtc_clk);
retry_get_time:
rtc_tm->tm_min = readb(base + S3C2410_RTCMIN);
rtc_tm->tm_hour = readb(base + S3C2410_RTCHOUR);
@@ -157,6 +166,7 @@ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
rtc_tm->tm_year += 100;
rtc_tm->tm_mon -= 1;
+ clk_disable(rtc_clk);
return rtc_valid_tm(rtc_tm);
}
@@ -165,6 +175,7 @@ static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
void __iomem *base = s3c_rtc_base;
int year = tm->tm_year - 100;
+ clk_enable(rtc_clk);
pr_debug("set time %04d.%02d.%02d %02d:%02d:%02d\n",
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
tm->tm_hour, tm->tm_min, tm->tm_sec);
@@ -182,6 +193,7 @@ static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm)
writeb(bin2bcd(tm->tm_mday), base + S3C2410_RTCDATE);
writeb(bin2bcd(tm->tm_mon + 1), base + S3C2410_RTCMON);
writeb(bin2bcd(year), base + S3C2410_RTCYEAR);
+ clk_disable(rtc_clk);
return 0;
}
@@ -192,6 +204,7 @@ static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
void __iomem *base = s3c_rtc_base;
unsigned int alm_en;
+ clk_enable(rtc_clk);
alm_tm->tm_sec = readb(base + S3C2410_ALMSEC);
alm_tm->tm_min = readb(base + S3C2410_ALMMIN);
alm_tm->tm_hour = readb(base + S3C2410_ALMHOUR);
@@ -243,6 +256,7 @@ static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
else
alm_tm->tm_year = -1;
+ clk_disable(rtc_clk);
return 0;
}
@@ -252,6 +266,7 @@ static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
void __iomem *base = s3c_rtc_base;
unsigned int alrm_en;
+ clk_enable(rtc_clk);
pr_debug("s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n",
alrm->enabled,
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
@@ -282,6 +297,7 @@ static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
s3c_rtc_setaie(dev, alrm->enabled);
+ clk_disable(rtc_clk);
return 0;
}
@@ -289,6 +305,7 @@ static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
{
unsigned int ticnt;
+ clk_enable(rtc_clk);
if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
ticnt = readw(s3c_rtc_base + S3C2410_RTCCON);
ticnt &= S3C64XX_RTCCON_TICEN;
@@ -298,6 +315,7 @@ static int s3c_rtc_proc(struct device *dev, struct seq_file *seq)
}
seq_printf(seq, "periodic_IRQ\t: %s\n", ticnt ? "yes" : "no");
+ clk_disable(rtc_clk);
return 0;
}
@@ -360,6 +378,7 @@ static void s3c_rtc_enable(struct platform_device *pdev, int en)
if (s3c_rtc_base == NULL)
return;
+ clk_enable(rtc_clk);
if (!en) {
tmp = readw(base + S3C2410_RTCCON);
if (s3c_rtc_cpu_type == TYPE_S3C64XX)
@@ -399,6 +418,7 @@ static void s3c_rtc_enable(struct platform_device *pdev, int en)
base + S3C2410_RTCCON);
}
}
+ clk_disable(rtc_clk);
}
static int __devexit s3c_rtc_remove(struct platform_device *dev)
@@ -410,7 +430,6 @@ static int __devexit s3c_rtc_remove(struct platform_device *dev)
s3c_rtc_setaie(&dev->dev, 0);
- clk_disable(rtc_clk);
clk_put(rtc_clk);
rtc_clk = NULL;
@@ -530,6 +549,8 @@ static int __devinit s3c_rtc_probe(struct platform_device *pdev)
s3c_rtc_setfreq(&pdev->dev, 1);
+ clk_disable(rtc_clk);
+
return 0;
err_nortc:
@@ -555,6 +576,7 @@ static int ticnt_save, ticnt_en_save;
static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
{
+ clk_enable(rtc_clk);
/* save TICNT for anyone using periodic interrupts */
ticnt_save = readb(s3c_rtc_base + S3C2410_TICNT);
if (s3c_rtc_cpu_type == TYPE_S3C64XX) {
@@ -569,6 +591,7 @@ static int s3c_rtc_suspend(struct platform_device *pdev, pm_message_t state)
else
dev_err(&pdev->dev, "enable_irq_wake failed\n");
}
+ clk_disable(rtc_clk);
return 0;
}
@@ -577,6 +600,7 @@ static int s3c_rtc_resume(struct platform_device *pdev)
{
unsigned int tmp;
+ clk_enable(rtc_clk);
s3c_rtc_enable(pdev, 1);
writeb(ticnt_save, s3c_rtc_base + S3C2410_TICNT);
if (s3c_rtc_cpu_type == TYPE_S3C64XX && ticnt_en_save) {
@@ -588,6 +612,7 @@ static int s3c_rtc_resume(struct platform_device *pdev)
disable_irq_wake(s3c_rtc_alarmno);
wake_en = false;
}
+ clk_disable(rtc_clk);
return 0;
}
--
1.7.4.1
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