-----Original Message-----
From: Oleksij Rempel [mailto:o.rempel at pengutronix.de]
Sent: 2018?7?26? 17:22
To: Shawn Guo <shawnguo@kernel.org>; Mark Brown <broonie@kernel.org>;
Rafael J. Wysocki [off-list ref]
Cc: Oleksij Rempel <o.rempel@pengutronix.de>; kernel at pengutronix.de;
devicetree at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
linux-clk at vger.kernel.org; linux-kernel at vger.kernel.org; Andrew Morton
[off-list ref]; Liam Girdwood [off-list ref];
Leonard Crestez [off-list ref]; Rob Herring
[off-list ref]; Mark Rutland [off-list ref]; Michael
Turquette [off-list ref]; Stephen Boyd
[off-list ref]; Fabio Estevam [off-list ref]; Russell
King [off-list ref]; dl-linux-imx [off-list ref]; Robin Gong
[off-list ref]; A.s. Dong [off-list ref]
Subject: [PATCH v8 2/6] ARM: imx6: register pm_power_off handler if
"fsl,pmic-stby-poweroff" is set

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:
https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.
nxp.com%2Fassets%2Fdocuments%2Fdata%2Fen%2Freference-manuals%2FIM
X6DQRM.pdf&amp;data=02%7C01%7Cyibin.gong%40nxp.com%7C193fd19e3a
40416ffa4a08d5f2d9583c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C1
%7C636681937661914076&amp;sdata=lICAelYpUh4%2Ft%2Fs7N9mdk2cLQMi
cHcOqQ07vTOUoyNY%3D&amp;reserved=0
page 5083

This patch implements step 4. of this sequence.

Signed-off-by: Oleksij Rempel <o.rempel@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 017539dd712b..2f5c643f62fb 100644
--- a/arch/arm/mach-imx/pm-imx6.c
+++ b/arch/arm/mach-imx/pm-imx6.c

@@ -601,6 +601,28 @@ 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);
+	imx6q_suspend_finish(0);
+
+	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;

@@ -617,6 +639,9 @@ 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)
--
2.18.0