* [PATCH 2/2] rtc: snvs: Add necessary clock operations for RTC APIs
2020-05-22 2:19 [PATCH 1/2] rtc: snvs: Make SNVS clock always prepared Anson Huang
@ 2020-05-22 2:19 ` Anson Huang
2020-05-30 1:21 ` [PATCH 1/2] rtc: snvs: Make SNVS clock always prepared Alexandre Belloni
1 sibling, 0 replies; 3+ messages in thread
From: Anson Huang @ 2020-05-22 2:19 UTC (permalink / raw)
To: a.zummo, alexandre.belloni, linux-rtc, linux-kernel; +Cc: Linux-imx
There could be still RTC registers access after RTC suspend
with clock disabled, need to add clock operations for each
RTC API to make sure accessing RTC registers is successfully.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
drivers/rtc/rtc-snvs.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 53 insertions(+), 2 deletions(-)
diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c
index b9371f4..0263d99 100644
--- a/drivers/rtc/rtc-snvs.c
+++ b/drivers/rtc/rtc-snvs.c
@@ -148,10 +148,21 @@ static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct snvs_rtc_data *data = dev_get_drvdata(dev);
- unsigned long time = rtc_read_lp_counter(data);
+ unsigned long time;
+ int ret;
+
+ if (data->clk) {
+ ret = clk_enable(data->clk);
+ if (ret)
+ return ret;
+ }
+ time = rtc_read_lp_counter(data);
rtc_time64_to_tm(time, tm);
+ if (data->clk)
+ clk_disable(data->clk);
+
return 0;
}
@@ -161,6 +172,12 @@ static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
unsigned long time = rtc_tm_to_time64(tm);
int ret;
+ if (data->clk) {
+ ret = clk_enable(data->clk);
+ if (ret)
+ return ret;
+ }
+
/* Disable RTC first */
ret = snvs_rtc_enable(data, false);
if (ret)
@@ -173,6 +190,9 @@ static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
/* Enable RTC again */
ret = snvs_rtc_enable(data, true);
+ if (data->clk)
+ clk_disable(data->clk);
+
return ret;
}
@@ -180,6 +200,13 @@ static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct snvs_rtc_data *data = dev_get_drvdata(dev);
u32 lptar, lpsr;
+ int ret;
+
+ if (data->clk) {
+ ret = clk_enable(data->clk);
+ if (ret)
+ return ret;
+ }
regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
rtc_time64_to_tm(lptar, &alrm->time);
@@ -187,18 +214,33 @@ static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;
+ if (data->clk)
+ clk_disable(data->clk);
+
return 0;
}
static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
{
struct snvs_rtc_data *data = dev_get_drvdata(dev);
+ int ret;
+
+ if (data->clk) {
+ ret = clk_enable(data->clk);
+ if (ret)
+ return ret;
+ }
regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
(SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN),
enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0);
- return rtc_write_sync_lp(data);
+ ret = rtc_write_sync_lp(data);
+
+ if (data->clk)
+ clk_disable(data->clk);
+
+ return ret;
}
static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
@@ -207,6 +249,12 @@ static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
unsigned long time = rtc_tm_to_time64(&alrm->time);
int ret;
+ if (data->clk) {
+ ret = clk_enable(data->clk);
+ if (ret)
+ return ret;
+ }
+
regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
ret = rtc_write_sync_lp(data);
if (ret)
@@ -216,6 +264,9 @@ static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
/* Clear alarm interrupt status bit */
regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);
+ if (data->clk)
+ clk_disable(data->clk);
+
return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
}
--
2.7.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH 1/2] rtc: snvs: Make SNVS clock always prepared
2020-05-22 2:19 [PATCH 1/2] rtc: snvs: Make SNVS clock always prepared Anson Huang
2020-05-22 2:19 ` [PATCH 2/2] rtc: snvs: Add necessary clock operations for RTC APIs Anson Huang
@ 2020-05-30 1:21 ` Alexandre Belloni
1 sibling, 0 replies; 3+ messages in thread
From: Alexandre Belloni @ 2020-05-30 1:21 UTC (permalink / raw)
To: linux-kernel, linux-rtc, Anson Huang, a.zummo
Cc: Alexandre Belloni, Linux-imx
On Fri, 22 May 2020 10:19:55 +0800, Anson Huang wrote:
> In IRQ handler, ONLY clock enable/disable is called due to
> clock prepare can NOT be called in interrupt context, but
> clock enable/disable will return failure if prepare count
> is 0, to fix this issue, just make SNVS clock always prepared
> there, the SNVS clock has no prepare function implemented,
> so it won't impact anything.
Applied, thanks!
[1/2] rtc: snvs: Make SNVS clock always prepared
commit: 20af67700bc39bccd838414128f63a72965de6e7
[2/2] rtc: snvs: Add necessary clock operations for RTC APIs
commit: 4b957bde561f3a56865395be06f1be2c196b0b5e
Best regards,
--
Alexandre Belloni <alexandre.belloni@bootlin.com>
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