* [PATCH v5 1/2] rtc: omap: use of_device_is_system_power_controller function
@ 2018-07-25 5:51 Keerthy
2018-07-25 5:51 ` [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec Keerthy
0 siblings, 1 reply; 7+ messages in thread
From: Keerthy @ 2018-07-25 5:51 UTC (permalink / raw)
To: a.zummo, alexandre.belloni
Cc: t-kristo, j-keerthy, linux-rtc, linux-omap, linux-kernel, johan
Use of_device_is_system_power_controller instead of manually reading
the system-power-controller property from the device tree node.
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Keerthy <j-keerthy@ti.com>
---
Changes in v5:
* Added Johan's Reviewed-by
drivers/rtc/rtc-omap.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 323ff55..44ff4cc 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -721,8 +721,7 @@ static int omap_rtc_probe(struct platform_device *pdev)
if (of_id) {
rtc->type = of_id->data;
rtc->is_pmic_controller = rtc->type->has_pmic_mode &&
- of_property_read_bool(pdev->dev.of_node,
- "system-power-controller");
+ of_device_is_system_power_controller(pdev->dev.of_node);
} else {
id_entry = platform_get_device_id(pdev);
rtc->type = (void *)id_entry->driver_data;
--
1.9.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec
2018-07-25 5:51 [PATCH v5 1/2] rtc: omap: use of_device_is_system_power_controller function Keerthy
@ 2018-07-25 5:51 ` Keerthy
2018-07-25 9:30 ` Alexandre Belloni
2018-08-14 9:23 ` Johan Hovold
0 siblings, 2 replies; 7+ messages in thread
From: Keerthy @ 2018-07-25 5:51 UTC (permalink / raw)
To: a.zummo, alexandre.belloni
Cc: t-kristo, j-keerthy, linux-rtc, linux-omap, linux-kernel, johan
Cut down the shutdown time from 2 seconds to 1 sec. In case of roll
over try again.
Signed-off-by: Keerthy <j-keerthy@ti.com>
---
Changes in v5:
* Added an additional check to see if ALARM2 status is not set
before retrying.
* Cleaned up comments
* Also reduced mdelay to 1S lesser as per this commit
drivers/rtc/rtc-omap.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 44ff4cc..caa6da6 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -421,12 +421,6 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
* The RTC can be used to control an external PMIC via the pmic_power_en pin,
* which can be configured to transition to OFF on ALARM2 events.
*
- * Notes:
- * The two-second alarm offset is the shortest offset possible as the alarm
- * registers must be set before the next timer update and the offset
- * calculation is too heavy for everything to be done within a single access
- * period (~15 us).
- *
* Called with local interrupts disabled.
*/
static void omap_rtc_power_off(void)
@@ -435,17 +429,20 @@ static void omap_rtc_power_off(void)
struct rtc_time tm;
unsigned long now;
u32 val;
+ int seconds;
rtc->type->unlock(rtc);
/* enable pmic_power_en control */
val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
- /* set alarm two seconds from now */
+again:
+ /* set alarm one second from now */
omap_rtc_read_time_raw(rtc, &tm);
+ seconds = tm.tm_sec;
bcd2tm(&tm);
rtc_tm_to_time(&tm, &now);
- rtc_time_to_tm(now + 2, &tm);
+ rtc_time_to_tm(now + 1, &tm);
if (tm2bcd(&tm) < 0) {
dev_err(&rtc->rtc->dev, "power off failed\n");
@@ -470,14 +467,25 @@ static void omap_rtc_power_off(void)
val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
+
+ /*
+ * first check if ALARM2 has fired, if not then check if
+ * our calculations started right before the rollover, try again
+ * in case of rollover
+ */
+ if (!(OMAP_RTC_STATUS_ALARM2 && rtc_read(omap_rtc_power_off_rtc,
+ OMAP_RTC_STATUS_REG)) &&
+ seconds != rtc_read(omap_rtc_power_off_rtc, OMAP_RTC_SECONDS_REG))
+ goto again;
+
rtc->type->lock(rtc);
/*
- * Wait for alarm to trigger (within two seconds) and external PMIC to
+ * Wait for alarm to trigger (within one second) and external PMIC to
* power off the system. Add a 500 ms margin for external latencies
* (e.g. debounce circuits).
*/
- mdelay(2500);
+ mdelay(1500);
}
static const struct rtc_class_ops omap_rtc_ops = {
--
1.9.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec
2018-07-25 5:51 ` [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec Keerthy
@ 2018-07-25 9:30 ` Alexandre Belloni
2018-08-14 9:27 ` Johan Hovold
2018-08-14 9:32 ` Keerthy
2018-08-14 9:23 ` Johan Hovold
1 sibling, 2 replies; 7+ messages in thread
From: Alexandre Belloni @ 2018-07-25 9:30 UTC (permalink / raw)
To: Keerthy; +Cc: a.zummo, t-kristo, linux-rtc, linux-omap, linux-kernel, johan
Hi,
On 25/07/2018 11:21:22+0530, Keerthy wrote:
> Cut down the shutdown time from 2 seconds to 1 sec. In case of roll
> over try again.
>
> Signed-off-by: Keerthy <j-keerthy@ti.com>
> ---
>
> Changes in v5:
>
> * Added an additional check to see if ALARM2 status is not set
> before retrying.
> * Cleaned up comments
> * Also reduced mdelay to 1S lesser as per this commit
>
> drivers/rtc/rtc-omap.c | 28 ++++++++++++++++++----------
> 1 file changed, 18 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> index 44ff4cc..caa6da6 100644
> --- a/drivers/rtc/rtc-omap.c
> +++ b/drivers/rtc/rtc-omap.c
> @@ -421,12 +421,6 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
> * The RTC can be used to control an external PMIC via the pmic_power_en pin,
> * which can be configured to transition to OFF on ALARM2 events.
> *
> - * Notes:
> - * The two-second alarm offset is the shortest offset possible as the alarm
> - * registers must be set before the next timer update and the offset
> - * calculation is too heavy for everything to be done within a single access
> - * period (~15 us).
> - *
> * Called with local interrupts disabled.
> */
> static void omap_rtc_power_off(void)
> @@ -435,17 +429,20 @@ static void omap_rtc_power_off(void)
> struct rtc_time tm;
> unsigned long now;
> u32 val;
> + int seconds;
>
> rtc->type->unlock(rtc);
> /* enable pmic_power_en control */
> val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
> rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
>
> - /* set alarm two seconds from now */
> +again:
> + /* set alarm one second from now */
> omap_rtc_read_time_raw(rtc, &tm);
> + seconds = tm.tm_sec;
> bcd2tm(&tm);
> rtc_tm_to_time(&tm, &now);
> - rtc_time_to_tm(now + 2, &tm);
> + rtc_time_to_tm(now + 1, &tm);
>
> if (tm2bcd(&tm) < 0) {
> dev_err(&rtc->rtc->dev, "power off failed\n");
> @@ -470,14 +467,25 @@ static void omap_rtc_power_off(void)
> val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
> rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
> val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
> +
> + /*
> + * first check if ALARM2 has fired, if not then check if
> + * our calculations started right before the rollover, try again
> + * in case of rollover
> + */
> + if (!(OMAP_RTC_STATUS_ALARM2 && rtc_read(omap_rtc_power_off_rtc,
> + OMAP_RTC_STATUS_REG)) &&
> + seconds != rtc_read(omap_rtc_power_off_rtc, OMAP_RTC_SECONDS_REG))
> + goto again;
> +
Can you use a while loop instead of goto?
> rtc->type->lock(rtc);
>
> /*
> - * Wait for alarm to trigger (within two seconds) and external PMIC to
> + * Wait for alarm to trigger (within one second) and external PMIC to
> * power off the system. Add a 500 ms margin for external latencies
> * (e.g. debounce circuits).
> */
> - mdelay(2500);
> + mdelay(1500);
> }
>
> static const struct rtc_class_ops omap_rtc_ops = {
> --
> 1.9.1
>
--
Alexandre Belloni, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec
2018-07-25 5:51 ` [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec Keerthy
2018-07-25 9:30 ` Alexandre Belloni
@ 2018-08-14 9:23 ` Johan Hovold
2018-08-14 9:54 ` Keerthy
1 sibling, 1 reply; 7+ messages in thread
From: Johan Hovold @ 2018-08-14 9:23 UTC (permalink / raw)
To: Keerthy
Cc: a.zummo, alexandre.belloni, t-kristo, linux-rtc, linux-omap,
linux-kernel, johan
On Wed, Jul 25, 2018 at 11:21:22AM +0530, Keerthy wrote:
> Cut down the shutdown time from 2 seconds to 1 sec. In case of roll
> over try again.
>
> Signed-off-by: Keerthy <j-keerthy@ti.com>
> ---
>
> Changes in v5:
>
> * Added an additional check to see if ALARM2 status is not set
> before retrying.
> * Cleaned up comments
> * Also reduced mdelay to 1S lesser as per this commit
>
> drivers/rtc/rtc-omap.c | 28 ++++++++++++++++++----------
> 1 file changed, 18 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> index 44ff4cc..caa6da6 100644
> --- a/drivers/rtc/rtc-omap.c
> +++ b/drivers/rtc/rtc-omap.c
> @@ -421,12 +421,6 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
> * The RTC can be used to control an external PMIC via the pmic_power_en pin,
> * which can be configured to transition to OFF on ALARM2 events.
> *
> - * Notes:
> - * The two-second alarm offset is the shortest offset possible as the alarm
> - * registers must be set before the next timer update and the offset
> - * calculation is too heavy for everything to be done within a single access
> - * period (~15 us).
> - *
> * Called with local interrupts disabled.
> */
> static void omap_rtc_power_off(void)
> @@ -435,17 +429,20 @@ static void omap_rtc_power_off(void)
> struct rtc_time tm;
> unsigned long now;
> u32 val;
> + int seconds;
Nit: I'd place this above val to maintain the reverse xmas-tree style.
>
> rtc->type->unlock(rtc);
> /* enable pmic_power_en control */
> val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
> rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
>
> - /* set alarm two seconds from now */
> +again:
> + /* set alarm one second from now */
> omap_rtc_read_time_raw(rtc, &tm);
> + seconds = tm.tm_sec;
> bcd2tm(&tm);
> rtc_tm_to_time(&tm, &now);
> - rtc_time_to_tm(now + 2, &tm);
> + rtc_time_to_tm(now + 1, &tm);
>
> if (tm2bcd(&tm) < 0) {
> dev_err(&rtc->rtc->dev, "power off failed\n");
> @@ -470,14 +467,25 @@ static void omap_rtc_power_off(void)
> val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
> rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
> val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
> +
> + /*
> + * first check if ALARM2 has fired, if not then check if
> + * our calculations started right before the rollover, try again
> + * in case of rollover
> + */
This is unnecessarily verbose; I'd rephrase it as something like:
/* Retry in case roll over happened before alarm was armed. */
> + if (!(OMAP_RTC_STATUS_ALARM2 && rtc_read(omap_rtc_power_off_rtc,
> + OMAP_RTC_STATUS_REG)) &&
> + seconds != rtc_read(omap_rtc_power_off_rtc, OMAP_RTC_SECONDS_REG))
> + goto again;
And this is clearly broken. First, you use boolean && instead of the &
bit operation.
Second, you need to check the status register *after* checking for
roll-over, as I already mentioned.
Also, use the rtc pointer rather than omap_rtc_power_off_rtc, which will
allow for more readable code.
I also strongly suggest you split the conditional, and use val to store
the status register value, that is:
if (rtc_read(rtc, OMAP_RTC_SECONDS_REG) != seconds) {
val = rtc_read(rtc, OMAP_RTC_STATUS_REG);
if (!(val & OMAP_RTC_STATUS_ALARM2))
goto again;
}
> +
> rtc->type->lock(rtc);
>
> /*
> - * Wait for alarm to trigger (within two seconds) and external PMIC to
> + * Wait for alarm to trigger (within one second) and external PMIC to
> * power off the system. Add a 500 ms margin for external latencies
> * (e.g. debounce circuits).
> */
> - mdelay(2500);
> + mdelay(1500);
> }
>
> static const struct rtc_class_ops omap_rtc_ops = {
Johan
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec
2018-07-25 9:30 ` Alexandre Belloni
@ 2018-08-14 9:27 ` Johan Hovold
2018-08-14 9:32 ` Keerthy
1 sibling, 0 replies; 7+ messages in thread
From: Johan Hovold @ 2018-08-14 9:27 UTC (permalink / raw)
To: Alexandre Belloni
Cc: Keerthy, a.zummo, t-kristo, linux-rtc, linux-omap, linux-kernel, johan
On Wed, Jul 25, 2018 at 11:30:18AM +0200, Alexandre Belloni wrote:
> Hi,
>
> On 25/07/2018 11:21:22+0530, Keerthy wrote:
> > Cut down the shutdown time from 2 seconds to 1 sec. In case of roll
> > over try again.
> >
> > Signed-off-by: Keerthy <j-keerthy@ti.com>
> > static void omap_rtc_power_off(void)
> > @@ -435,17 +429,20 @@ static void omap_rtc_power_off(void)
> > struct rtc_time tm;
> > unsigned long now;
> > u32 val;
> > + int seconds;
> >
> > rtc->type->unlock(rtc);
> > /* enable pmic_power_en control */
> > val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
> > rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
> >
> > - /* set alarm two seconds from now */
> > +again:
> > + /* set alarm one second from now */
> > omap_rtc_read_time_raw(rtc, &tm);
> > + seconds = tm.tm_sec;
> > bcd2tm(&tm);
> > rtc_tm_to_time(&tm, &now);
> > - rtc_time_to_tm(now + 2, &tm);
> > + rtc_time_to_tm(now + 1, &tm);
> >
> > if (tm2bcd(&tm) < 0) {
> > dev_err(&rtc->rtc->dev, "power off failed\n");
> > @@ -470,14 +467,25 @@ static void omap_rtc_power_off(void)
> > val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
> > rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
> > val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
> > +
> > + /*
> > + * first check if ALARM2 has fired, if not then check if
> > + * our calculations started right before the rollover, try again
> > + * in case of rollover
> > + */
> > + if (!(OMAP_RTC_STATUS_ALARM2 && rtc_read(omap_rtc_power_off_rtc,
> > + OMAP_RTC_STATUS_REG)) &&
> > + seconds != rtc_read(omap_rtc_power_off_rtc, OMAP_RTC_SECONDS_REG))
> > + goto again;
> > +
>
> Can you use a while loop instead of goto?
I think a goto is warranted here as it allows for more readable code
with less indentation. And the exception case it is used for is truly an
exception that a single retry would take care of.
Johan
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec
2018-07-25 9:30 ` Alexandre Belloni
2018-08-14 9:27 ` Johan Hovold
@ 2018-08-14 9:32 ` Keerthy
1 sibling, 0 replies; 7+ messages in thread
From: Keerthy @ 2018-08-14 9:32 UTC (permalink / raw)
To: Alexandre Belloni
Cc: a.zummo, t-kristo, linux-rtc, linux-omap, linux-kernel, johan
On Wednesday 25 July 2018 03:00 PM, Alexandre Belloni wrote:
> Hi,
>
> On 25/07/2018 11:21:22+0530, Keerthy wrote:
>> Cut down the shutdown time from 2 seconds to 1 sec. In case of roll
>> over try again.
>>
>> Signed-off-by: Keerthy <j-keerthy@ti.com>
>> ---
>>
>> Changes in v5:
>>
>> * Added an additional check to see if ALARM2 status is not set
>> before retrying.
>> * Cleaned up comments
>> * Also reduced mdelay to 1S lesser as per this commit
>>
>> drivers/rtc/rtc-omap.c | 28 ++++++++++++++++++----------
>> 1 file changed, 18 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
>> index 44ff4cc..caa6da6 100644
>> --- a/drivers/rtc/rtc-omap.c
>> +++ b/drivers/rtc/rtc-omap.c
>> @@ -421,12 +421,6 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
>> * The RTC can be used to control an external PMIC via the pmic_power_en pin,
>> * which can be configured to transition to OFF on ALARM2 events.
>> *
>> - * Notes:
>> - * The two-second alarm offset is the shortest offset possible as the alarm
>> - * registers must be set before the next timer update and the offset
>> - * calculation is too heavy for everything to be done within a single access
>> - * period (~15 us).
>> - *
>> * Called with local interrupts disabled.
>> */
>> static void omap_rtc_power_off(void)
>> @@ -435,17 +429,20 @@ static void omap_rtc_power_off(void)
>> struct rtc_time tm;
>> unsigned long now;
>> u32 val;
>> + int seconds;
>>
>> rtc->type->unlock(rtc);
>> /* enable pmic_power_en control */
>> val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
>> rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
>>
>> - /* set alarm two seconds from now */
>> +again:
>> + /* set alarm one second from now */
>> omap_rtc_read_time_raw(rtc, &tm);
>> + seconds = tm.tm_sec;
>> bcd2tm(&tm);
>> rtc_tm_to_time(&tm, &now);
>> - rtc_time_to_tm(now + 2, &tm);
>> + rtc_time_to_tm(now + 1, &tm);
>>
>> if (tm2bcd(&tm) < 0) {
>> dev_err(&rtc->rtc->dev, "power off failed\n");
>> @@ -470,14 +467,25 @@ static void omap_rtc_power_off(void)
>> val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
>> rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
>> val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
>> +
>> + /*
>> + * first check if ALARM2 has fired, if not then check if
>> + * our calculations started right before the rollover, try again
>> + * in case of rollover
>> + */
>> + if (!(OMAP_RTC_STATUS_ALARM2 && rtc_read(omap_rtc_power_off_rtc,
>> + OMAP_RTC_STATUS_REG)) &&
>> + seconds != rtc_read(omap_rtc_power_off_rtc, OMAP_RTC_SECONDS_REG))
>> + goto again;
>> +
>
> Can you use a while loop instead of goto?
Apologies for the late reply. A one time retry should be able to take
care of the exception case.
>
>> rtc->type->lock(rtc);
>>
>> /*
>> - * Wait for alarm to trigger (within two seconds) and external PMIC to
>> + * Wait for alarm to trigger (within one second) and external PMIC to
>> * power off the system. Add a 500 ms margin for external latencies
>> * (e.g. debounce circuits).
>> */
>> - mdelay(2500);
>> + mdelay(1500);
>> }
>>
>> static const struct rtc_class_ops omap_rtc_ops = {
>> --
>> 1.9.1
>>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec
2018-08-14 9:23 ` Johan Hovold
@ 2018-08-14 9:54 ` Keerthy
0 siblings, 0 replies; 7+ messages in thread
From: Keerthy @ 2018-08-14 9:54 UTC (permalink / raw)
To: Johan Hovold
Cc: a.zummo, alexandre.belloni, t-kristo, linux-rtc, linux-omap,
linux-kernel
On Tuesday 14 August 2018 02:53 PM, Johan Hovold wrote:
> On Wed, Jul 25, 2018 at 11:21:22AM +0530, Keerthy wrote:
>> Cut down the shutdown time from 2 seconds to 1 sec. In case of roll
>> over try again.
>>
>> Signed-off-by: Keerthy <j-keerthy@ti.com>
>> ---
>>
>> Changes in v5:
>>
>> * Added an additional check to see if ALARM2 status is not set
>> before retrying.
>> * Cleaned up comments
>> * Also reduced mdelay to 1S lesser as per this commit
>>
>> drivers/rtc/rtc-omap.c | 28 ++++++++++++++++++----------
>> 1 file changed, 18 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
>> index 44ff4cc..caa6da6 100644
>> --- a/drivers/rtc/rtc-omap.c
>> +++ b/drivers/rtc/rtc-omap.c
>> @@ -421,12 +421,6 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
>> * The RTC can be used to control an external PMIC via the pmic_power_en pin,
>> * which can be configured to transition to OFF on ALARM2 events.
>> *
>> - * Notes:
>> - * The two-second alarm offset is the shortest offset possible as the alarm
>> - * registers must be set before the next timer update and the offset
>> - * calculation is too heavy for everything to be done within a single access
>> - * period (~15 us).
>> - *
>> * Called with local interrupts disabled.
>> */
>> static void omap_rtc_power_off(void)
>> @@ -435,17 +429,20 @@ static void omap_rtc_power_off(void)
>> struct rtc_time tm;
>> unsigned long now;
>> u32 val;
>> + int seconds;
>
> Nit: I'd place this above val to maintain the reverse xmas-tree style.
okay
>
>>
>> rtc->type->unlock(rtc);
>> /* enable pmic_power_en control */
>> val = rtc_readl(rtc, OMAP_RTC_PMIC_REG);
>> rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN);
>>
>> - /* set alarm two seconds from now */
>> +again:
>> + /* set alarm one second from now */
>> omap_rtc_read_time_raw(rtc, &tm);
>> + seconds = tm.tm_sec;
>> bcd2tm(&tm);
>> rtc_tm_to_time(&tm, &now);
>> - rtc_time_to_tm(now + 2, &tm);
>> + rtc_time_to_tm(now + 1, &tm);
>>
>> if (tm2bcd(&tm) < 0) {
>> dev_err(&rtc->rtc->dev, "power off failed\n");
>> @@ -470,14 +467,25 @@ static void omap_rtc_power_off(void)
>> val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
>> rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG,
>> val | OMAP_RTC_INTERRUPTS_IT_ALARM2);
>> +
>> + /*
>> + * first check if ALARM2 has fired, if not then check if
>> + * our calculations started right before the rollover, try again
>> + * in case of rollover
>> + */
>
> This is unnecessarily verbose; I'd rephrase it as something like:
>
> /* Retry in case roll over happened before alarm was armed. */
Okay
>
>> + if (!(OMAP_RTC_STATUS_ALARM2 && rtc_read(omap_rtc_power_off_rtc,
>> + OMAP_RTC_STATUS_REG)) &&
>> + seconds != rtc_read(omap_rtc_power_off_rtc, OMAP_RTC_SECONDS_REG))
>> + goto again;
>
> And this is clearly broken. First, you use boolean && instead of the &
> bit operation.
Ah my bad. I will fix it.
>
> Second, you need to check the status register *after* checking for
> roll-over, as I already mentioned.
>
> Also, use the rtc pointer rather than omap_rtc_power_off_rtc, which will
> allow for more readable code.
Okay
>
> I also strongly suggest you split the conditional, and use val to store
> the status register value, that is:
>
> if (rtc_read(rtc, OMAP_RTC_SECONDS_REG) != seconds) {
> val = rtc_read(rtc, OMAP_RTC_STATUS_REG);
> if (!(val & OMAP_RTC_STATUS_ALARM2))
> goto again;
> }
>
>> +
>> rtc->type->lock(rtc);
>>
>> /*
>> - * Wait for alarm to trigger (within two seconds) and external PMIC to
>> + * Wait for alarm to trigger (within one second) and external PMIC to
>> * power off the system. Add a 500 ms margin for external latencies
>> * (e.g. debounce circuits).
>> */
>> - mdelay(2500);
>> + mdelay(1500);
>> }
>>
>> static const struct rtc_class_ops omap_rtc_ops = {
>
> Johan
>
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2018-08-14 9:56 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-07-25 5:51 [PATCH v5 1/2] rtc: omap: use of_device_is_system_power_controller function Keerthy
2018-07-25 5:51 ` [PATCH v5 2/2] rtc: omap: Cut down the shutdown time from 2 seconds to 1 sec Keerthy
2018-07-25 9:30 ` Alexandre Belloni
2018-08-14 9:27 ` Johan Hovold
2018-08-14 9:32 ` Keerthy
2018-08-14 9:23 ` Johan Hovold
2018-08-14 9:54 ` Keerthy
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