One of the Freescale recommended sequences for power off with external
PMIC is the following:
...
3.  SoC is programming PMIC for power off when standby is asserted.
4.  In CCM STOP mode, Standby is asserted, PMIC gates SoC supplies.

See:
http://www.nxp.com/assets/documents/data/en/reference-manuals/IMX6DQRM.pdf
page 5083

This patch implements step 4. of this sequence.

Signed-off-by: Oleksij Rempel <o.rem...@pengutronix.de>
---
 arch/arm/mach-imx/pm-imx6.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/arch/arm/mach-imx/pm-imx6.c b/arch/arm/mach-imx/pm-imx6.c
index ecdf071653d4..24689260a2a5 100644
--- a/arch/arm/mach-imx/pm-imx6.c
+++ b/arch/arm/mach-imx/pm-imx6.c
@@ -604,6 +604,28 @@ static void __init imx6_pm_common_init(const struct 
imx6_pm_socdata
                                   IMX6Q_GPR1_GINT);
 }
 
+static void imx6_pm_stby_poweroff(void)
+{
+       imx6_set_lpm(STOP_POWER_OFF);
+       cpu_suspend(0, imx6q_suspend_finish);
+
+       mdelay(1000);
+
+       pr_emerg("Unable to poweroff system\n");
+}
+
+static int imx6_pm_stby_poweroff_probe(void)
+{
+       if (pm_power_off) {
+               pr_warn("%s: pm_power_off already claimed  %p %pf!\n",
+                       __func__, pm_power_off, pm_power_off);
+               return -EBUSY;
+       }
+
+       pm_power_off = imx6_pm_stby_poweroff;
+       return 0;
+}
+
 void __init imx6_pm_ccm_init(const char *ccm_compat)
 {
        struct device_node *np;
@@ -620,6 +642,9 @@ void __init imx6_pm_ccm_init(const char *ccm_compat)
        val = readl_relaxed(ccm_base + CLPCR);
        val &= ~BM_CLPCR_LPM;
        writel_relaxed(val, ccm_base + CLPCR);
+
+       if (of_property_read_bool(np, "fsl,pmic-stby-poweroff"))
+               imx6_pm_stby_poweroff_probe();
 }
 
 void __init imx6q_pm_init(void)
-- 
2.16.1

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