[PATCH v4 1/4] rtc: OMAP: Add system pm_power_off to rtc driver
AnilKumar, Chimata
anilkumar at ti.com
Fri Jan 11 04:55:05 EST 2013
On Fri, Jan 11, 2013 at 15:00:03, AnilKumar, Chimata wrote:
> On Fri, Jan 11, 2013 at 14:24:46, Russ Dill wrote:
> > On Fri, Jan 11, 2013 at 12:08 AM, Russ Dill <russ.dill at gmail.com> wrote:
> > > On Thu, Dec 13, 2012 at 10:03 PM, AnilKumar Ch <anilkumar at ti.com> wrote:
> > >> From: Colin Foe-Parker <colin.foeparker at logicpd.com>
> > >>
> > >> Add system power off control to rtc driver which is the in-charge
> > >> of controlling the BeagleBone system power. The power_off routine
> > >> can be hooked up to "pm_power_off" system call.
> > >>
> > >> System power off sequence:-
> > >> * Set PMIC STATUS_OFF when PMIC_POWER_EN is pulled low
> > >> * Enable PMIC_POWER_EN in rtc module
> > >> * Set rtc ALARM2 time
> > >> * Enable ALARM2 interrupt
> > >>
> > >> Signed-off-by: Colin Foe-Parker <colin.foeparker at logicpd.com>
> > >> [anilkumar at ti.com: move poweroff additions to rtc driver]
> > >> Signed-off-by: AnilKumar Ch <anilkumar at ti.com>
> > >
> > > Looks good
> > >
> > > Reviewed-by: Russ Dill <russ.dill at ti.com>
> > > Acked-by: Russ Dill <russ.dill at ti.com>
> >
> > Sorry, actually, small follow up. Is there any reason this uses
> > readl/writel in some places rather than rtc_read/rtc_write?
>
> Hi Russ Dill,
>
> Thanks for the review
>
> At OMAP_RTC_PMIC_POWER_EN_EN, 32-bit value needs to modified so
> readl/writel are used. While enabling the INTERRUPTS we can change
> it to rtc_read/rtc_write but I am not seeing any advantage if we
> do that apart from consistency.
And driver has to clean-up properly to make use of rtc_read/write
APIs with proper read/write's based on the memory type. Ideally
rtc_readb/w/l and rtc_writeb/w/l should go way from the driver.
This clean-up can be done while converting the driver with platform
specific rtc_read/write.
Thanks
AnilKumar
> > >> ---
> > >> Documentation/devicetree/bindings/rtc/rtc-omap.txt | 5 ++
> > >> drivers/rtc/rtc-omap.c | 74 +++++++++++++++++++-
> > >> 2 files changed, 78 insertions(+), 1 deletion(-)
> > >>
> > >> diff --git a/Documentation/devicetree/bindings/rtc/rtc-omap.txt b/Documentation/devicetree/bindings/rtc/rtc-omap.txt
> > >> index b47aa41..8d9f4f9 100644
> > >> --- a/Documentation/devicetree/bindings/rtc/rtc-omap.txt
> > >> +++ b/Documentation/devicetree/bindings/rtc/rtc-omap.txt
> > >> @@ -6,6 +6,10 @@ Required properties:
> > >> - interrupts: rtc timer, alarm interrupts in order
> > >> - interrupt-parent: phandle for the interrupt controller
> > >>
> > >> +Optional properties:
> > >> +- ti,system-power-controller: Telling whether or not rtc is controlling
> > >> + the system power.
> > >> +
> > >> Example:
> > >>
> > >> rtc at 1c23000 {
> > >> @@ -14,4 +18,5 @@ rtc at 1c23000 {
> > >> interrupts = <19
> > >> 19>;
> > >> interrupt-parent = <&intc>;
> > >> + ti,system-power-controller;
> > >> };
> > >> diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
> > >> index 6009714..e6d4878 100644
> > >> --- a/drivers/rtc/rtc-omap.c
> > >> +++ b/drivers/rtc/rtc-omap.c
> > >> @@ -72,6 +72,14 @@
> > >> #define OMAP_RTC_KICK0_REG 0x6c
> > >> #define OMAP_RTC_KICK1_REG 0x70
> > >>
> > >> +#define OMAP_RTC_ALARM2_SECONDS_REG 0x80
> > >> +#define OMAP_RTC_ALARM2_MINUTES_REG 0x84
> > >> +#define OMAP_RTC_ALARM2_HOURS_REG 0x88
> > >> +#define OMAP_RTC_ALARM2_DAYS_REG 0x8c
> > >> +#define OMAP_RTC_ALARM2_MONTHS_REG 0x90
> > >> +#define OMAP_RTC_ALARM2_YEARS_REG 0x94
> > >> +#define OMAP_RTC_PMIC_REG 0x98
> > >> +
> > >> /* OMAP_RTC_CTRL_REG bit fields: */
> > >> #define OMAP_RTC_CTRL_SPLIT (1<<7)
> > >> #define OMAP_RTC_CTRL_DISABLE (1<<6)
> > >> @@ -93,15 +101,21 @@
> > >> #define OMAP_RTC_STATUS_BUSY (1<<0)
> > >>
> > >> /* OMAP_RTC_INTERRUPTS_REG bit fields: */
> > >> +#define OMAP_RTC_INTERRUPTS_IT_ALARM2 (1<<4)
> > >> #define OMAP_RTC_INTERRUPTS_IT_ALARM (1<<3)
> > >> #define OMAP_RTC_INTERRUPTS_IT_TIMER (1<<2)
> > >>
> > >> +/* OMAP_RTC_PMIC_REG bit fields: */
> > >> +#define OMAP_RTC_PMIC_POWER_EN_EN (1<<16)
> > >> +
> > >> /* OMAP_RTC_KICKER values */
> > >> #define KICK0_VALUE 0x83e70b13
> > >> #define KICK1_VALUE 0x95a4f1e0
> > >>
> > >> #define OMAP_RTC_HAS_KICKER 0x1
> > >>
> > >> +#define SHUTDOWN_TIME_SEC 2
> > >> +
> > >> static void __iomem *rtc_base;
> > >>
> > >> #define rtc_read(addr) readb(rtc_base + (addr))
> > >> @@ -290,6 +304,56 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
> > >> return 0;
> > >> }
> > >>
> > >> +/*
> > >> + * rtc_power_off: Set the pmic power off sequence. The RTC generates
> > >> + * pmic_pwr_enable control, which can be used to control an external
> > >> + * PMIC.
> > >> + */
> > >> +static void rtc_power_off(void)
> > >> +{
> > >> + u32 val;
> > >> + struct rtc_time tm;
> > >> + unsigned long time;
> > >> +
> > >> + /* Set PMIC power enable */
> > >> + val = readl(rtc_base + OMAP_RTC_PMIC_REG);
> > >> + writel(val | OMAP_RTC_PMIC_POWER_EN_EN, rtc_base + OMAP_RTC_PMIC_REG);
> > >> +
> > >> + /* Read rtc time */
> > >> + omap_rtc_read_time(NULL, &tm);
> > >> +
> > >> + /* Convert Gregorian date to seconds since 01-01-1970 00:00:00 */
> > >> + rtc_tm_to_time(&tm, &time);
> > >> +
> > >> + /* Add shutdown time to the current value */
> > >> + time += SHUTDOWN_TIME_SEC;
> > >> +
> > >> + /* Convert seconds since 01-01-1970 00:00:00 to Gregorian date */
> > >> + rtc_time_to_tm(time, &tm);
> > >> +
> > >> + if (tm2bcd(&tm) < 0)
> > >> + return;
> > >> +
> > >> + pr_info("System will go to power_off state in approx. %d secs\n",
> > >> + SHUTDOWN_TIME_SEC);
> > >> +
> > >> + /*
> > >> + * pmic_pwr_enable is controlled by means of ALARM2 event. So here
> > >> + * programming alarm2 expiry time and enabling alarm2 interrupt
> > >> + */
> > >> + rtc_write(tm.tm_sec, OMAP_RTC_ALARM2_SECONDS_REG);
> > >> + rtc_write(tm.tm_min, OMAP_RTC_ALARM2_MINUTES_REG);
> > >> + rtc_write(tm.tm_hour, OMAP_RTC_ALARM2_HOURS_REG);
> > >> + rtc_write(tm.tm_mday, OMAP_RTC_ALARM2_DAYS_REG);
> > >> + rtc_write(tm.tm_mon, OMAP_RTC_ALARM2_MONTHS_REG);
> > >> + rtc_write(tm.tm_year, OMAP_RTC_ALARM2_YEARS_REG);
> > >> +
> > >> + /* Enable alarm2 interrupt */
> > >> + val = readl(rtc_base + OMAP_RTC_INTERRUPTS_REG);
> > >> + writel(val | OMAP_RTC_INTERRUPTS_IT_ALARM2,
> > >> + rtc_base + OMAP_RTC_INTERRUPTS_REG);
> > >> +}
> > >> +
> > >> static struct rtc_class_ops omap_rtc_ops = {
> > >> .read_time = omap_rtc_read_time,
> > >> .set_time = omap_rtc_set_time,
> > >> @@ -327,12 +391,16 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
> > >> struct resource *res, *mem;
> > >> struct rtc_device *rtc;
> > >> u8 reg, new_ctrl;
> > >> + bool pm_off = false;
> > >> const struct platform_device_id *id_entry;
> > >> const struct of_device_id *of_id;
> > >>
> > >> of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
> > >> - if (of_id)
> > >> + if (of_id) {
> > >> pdev->id_entry = of_id->data;
> > >> + pm_off = of_property_read_bool(pdev->dev.of_node,
> > >> + "ti,system-power-controller");
> > >> + }
> > >>
> > >> omap_rtc_timer = platform_get_irq(pdev, 0);
> > >> if (omap_rtc_timer <= 0) {
> > >> @@ -385,6 +453,10 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
> > >> platform_set_drvdata(pdev, rtc);
> > >> dev_set_drvdata(&rtc->dev, mem);
> > >>
> > >> + /* RTC power off */
> > >> + if (pm_off && !pm_power_off)
> > >> + pm_power_off = rtc_power_off;
> > >> +
> > >> /* clear pending irqs, and set 1/second periodic,
> > >> * which we'll use instead of update irqs
> > >> */
> > >> --
> > >> 1.7.9.5
> > >>
> > >> --
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> >
>
>
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