[PATCH v4 1/4] rtc: OMAP: Add system pm_power_off to rtc driver

Russ Dill russ.dill at gmail.com
Fri Jan 11 19:08:41 EST 2013


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>

> ---
>  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
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


More information about the devicetree-discuss mailing list