Re: [PATCH v1] rtc: snvs: add poweroff function

Robin Gong
2014-09-26T02:14:39Z

On Fri, Sep 26, 2014 at 09:24:11AM +0800, Shawn Guo wrote:
> On Thu, Sep 25, 2014 at 10:13:53AM +0800, Robin Gong wrote:
> > On i.mx6 chips, PMIC_ON_REQ can be pulled by snvs LPCR. That can be
> > used poweroff system if PMIC_ON_REQ connected with external PMIC or
> > power control circuit.Power up again if PMIC_ON_REQ pulled high.
> >
> > Signed-off-by: Robin Gong <b38343@freescale.com>
>
> I'm not sure it's a good idea to plug poweroff support into RTC driver.
> If RTC driver is built out, poweroff function is gone too.
>
> Shawn
>
Yes, that's true since there is no real SNVS driver, only snvs-rtc and
snvs-caam driver. I'll pick up the patch about the driver which located
in drivers/power/reset.
> > ---
> > Documentation/devicetree/bindings/crypto/fsl-sec4.txt | 4 ++++
> > drivers/rtc/rtc-snvs.c | 18 ++++++++++++++++++
> > 2 files changed, 22 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/crypto/fsl-sec4.txt b/Documentation/devicetree/bindings/crypto/fsl-sec4.txt
> > index e402277..00d67f2 100644
> > --- a/Documentation/devicetree/bindings/crypto/fsl-sec4.txt
> > +++ b/Documentation/devicetree/bindings/crypto/fsl-sec4.txt
> > @@ -363,11 +363,15 @@ Secure Non-Volatile Storage (SNVS) Low Power (LP) RTC Node
> > Value type: <prop-encoded-array>
> > Definition: A standard property. Specifies the physical
> > address and length of the SNVS LP configuration registers.
> > + - fsl,poweroff
> > + Usage: opertional, recommend if PMIC_ON_REQ connected with external
> > + PMIC or power control circuit.
> >
> > EXAMPLE
> > sec_mon_rtc_lp@314000 {
> > compatible = "fsl,sec-v4.0-mon-rtc-lp";
> > reg = <0x34 0x58>;
> > + fsl,poweroff;
> > };
> >
> > =====================================================================
> > diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c
> > index fa384fe..ef32541 100644
> > --- a/drivers/rtc/rtc-snvs.c
> > +++ b/drivers/rtc/rtc-snvs.c
> > @@ -29,6 +29,8 @@
> > #define SNVS_LPCR_SRTC_ENV (1 << 0)
> > #define SNVS_LPCR_LPTA_EN (1 << 1)
> > #define SNVS_LPCR_LPWUI_EN (1 << 3)
> > +#define SNVS_LPCR_DP (1 << 5)
> > +#define SNVS_LPCR_TOP (1 << 6)
> > #define SNVS_LPSR_LPTA (1 << 0)
> >
> > #define SNVS_LPPGDR_INIT 0x41736166
> > @@ -41,6 +43,8 @@ struct snvs_rtc_data {
> > spinlock_t lock;
> > };
> >
> > +static void __iomem *snvs_base;
> > +
> > static u32 rtc_read_lp_counter(void __iomem *ioaddr)
> > {
> > u64 read1, read2;
> > @@ -241,8 +245,17 @@ static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
> > return events ? IRQ_HANDLED : IRQ_NONE;
> > }
> >
> > +static void snvs_poweroff(void)
> > +{
> > + u32 value;
> > +
> > + value = readl(snvs_base + SNVS_LPCR);
> > + writel(value | SNVS_LPCR_DP | SNVS_LPCR_TOP, snvs_base + SNVS_LPCR);
> > +}
> > +
> > static int snvs_rtc_probe(struct platform_device *pdev)
> > {
> > + struct device_node *np = pdev->dev.of_node;
> > struct snvs_rtc_data *data;
> > struct resource *res;
> > int ret;
> > @@ -260,6 +273,11 @@ static int snvs_rtc_probe(struct platform_device *pdev)
> > if (data->irq < 0)
> > return data->irq;
> >
> > + if (np && of_get_property(np, "fsl,poweroff", NULL)) {
> > + snvs_base = data->ioaddr;
> > + pm_power_off = snvs_poweroff;
> > + }
> > +
> > platform_set_drvdata(pdev, data);
> >
> > spin_lock_init(&data->lock);
> > --
> > 1.9.1
> >