[PATCH v6 6/6] ARM: dts: imx6: RIoTboard provide standby on power off option

[Oleksij Rempel]

This board, as well as some other boards with i.MX6 and a PMIC, uses a
"PMIC_STBY_REQ" line to notify the PMIC about a state change.
The PMIC is programmed for a specific state change before triggering the
line.
In this case, PMIC_STBY_REQ can be used for stand by, sleep
and power off modes.

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
---
arch/arm/boot/dts/imx6dl-riotboard.dts | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/imx6dl-riotboard.dts b/arch/arm/boot/dts/imx6dl-riotboard.dts
index 2cb72824e800..da9d0c102a31 100644
--- a/arch/arm/boot/dts/imx6dl-riotboard.dts
+++ b/arch/arm/boot/dts/imx6dl-riotboard.dts
@@ -90,6 +90,10 @@
status = "okay";
};

+&clks {
+ fsl,pmic-stby-poweroff;
+};
+
&fec {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_enet>;
@@ -125,6 +129,7 @@
reg = <0x08>;
interrupt-parent = <&gpio5>;
interrupts = <16 8>;
+ fsl,pmic-stby-poweroff;

regulators {
reg_vddcore: sw1ab { /* VDDARM_IN */

[Oleksij Rempel]

Document the new optional "fsl,pmic-stby-poweroff" property.

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
Acked-by: Rob Herring <***@kernel.org>
---
Documentation/devicetree/bindings/regulator/pfuze100.txt | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/regulator/pfuze100.txt b/Documentation/devicetree/bindings/regulator/pfuze100.txt
index 444c47831a40..197f1a52e960 100644
--- a/Documentation/devicetree/bindings/regulator/pfuze100.txt
+++ b/Documentation/devicetree/bindings/regulator/pfuze100.txt
@@ -4,6 +4,13 @@ Required properties:
- compatible: "fsl,pfuze100", "fsl,pfuze200", "fsl,pfuze3000"
- reg: I2C slave address

+Optional properties:
+- fsl,pmic-stby-poweroff: if present, configure the PMIC to shutdown all
+ power rails when PMIC_STBY_REQ line is asserted during the power off sequence.
+ Use this option if the SoC should be powered off by external power
+ management IC (PMIC) on PMIC_STBY_REQ signal.
+ As opposite to PMIC_STBY_REQ boards can implement PMIC_ON_REQ signal.
+
Required child node:
- regulators: This is the list of child nodes that specify the regulator
initialization data for defined regulators. Please refer to below doc

[Oleksij Rempel]

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 <***@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 e61b1d1027e1..0f141caa71f6 100644
--- a/arch/arm/mach-imx/pm-imx6.c
+++ b/arch/arm/mach-imx/pm-imx6.c
@@ -602,6 +602,28 @@ 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;
@@ -618,6 +640,9 @@ 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)

[Oleksij Rempel]

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
Acked-by: Rob Herring <***@kernel.org>
---
Documentation/devicetree/bindings/clock/imx6q-clock.txt | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/clock/imx6q-clock.txt b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
index 9252912a5b0e..8f93e1503e59 100644
--- a/Documentation/devicetree/bindings/clock/imx6q-clock.txt
+++ b/Documentation/devicetree/bindings/clock/imx6q-clock.txt
@@ -6,6 +6,14 @@ Required properties:
- interrupts: Should contain CCM interrupt
- #clock-cells: Should be <1>

+Optional properties:
+- fsl,pmic-stby-poweroff: Configure CCM to assert PMIC_STBY_REQ signal
+ on power off.
+ Use this property if the SoC should be powered off by external power
+ management IC (PMIC) triggered via PMIC_STBY_REQ signal.
+ Boards that are designed to initiate poweroff on PMIC_ON_REQ signal should
+ be using "syscon-poweroff" driver instead.
+
The clock consumer should specify the desired clock by having the clock
ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx6qdl-clock.h
for the full list of i.MX6 Quad and DualLite clock IDs.

[Oleksij Rempel]

On some boards the SoC can use one pin "PMIC_STBY_REQ" to notify th PMIC
about state changes. In this case internal state of PMIC must be
preconfigured for upcomming state change.
It works fine with the current regulator framework, except with the
power-off case.

This patch is providing an optional pm_power_off_prepare handler
which will configure standby state of the PMIC to disable all power lines.

In my power consumption test on RIoTBoard, I got the following results:
power off without this patch: 320 mA
power off with this patch: 2 mA
suspend to ram: 40 mA

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
---
drivers/regulator/pfuze100-regulator.c | 92 ++++++++++++++++++++++++++++++++++
1 file changed, 92 insertions(+)

diff --git a/drivers/regulator/pfuze100-regulator.c b/drivers/regulator/pfuze100-regulator.c
index 63922a2167e5..f6c276ed91d8 100644
--- a/drivers/regulator/pfuze100-regulator.c
+++ b/drivers/regulator/pfuze100-regulator.c
@@ -28,6 +28,7 @@
#include <linux/regulator/pfuze100.h>
#include <linux/i2c.h>
#include <linux/slab.h>
+#include <linux/kallsyms.h>
#include <linux/regmap.h>

#define PFUZE_NUMREGS 128
@@ -42,11 +43,17 @@

#define PFUZE100_COINVOL 0x1a
#define PFUZE100_SW1ABVOL 0x20
+#define PFUZE100_SW1ABMODE 0x23
#define PFUZE100_SW1CVOL 0x2e
+#define PFUZE100_SW1CMODE 0x31
#define PFUZE100_SW2VOL 0x35
+#define PFUZE100_SW2MODE 0x38
#define PFUZE100_SW3AVOL 0x3c
+#define PFUZE100_SW3AMODE 0x3f
#define PFUZE100_SW3BVOL 0x43
+#define PFUZE100_SW3BMODE 0x46
#define PFUZE100_SW4VOL 0x4a
+#define PFUZE100_SW4MODE 0x4d
#define PFUZE100_SWBSTCON1 0x66
#define PFUZE100_VREFDDRCON 0x6a
#define PFUZE100_VSNVSVOL 0x6b
@@ -57,6 +64,13 @@
#define PFUZE100_VGEN5VOL 0x70
#define PFUZE100_VGEN6VOL 0x71

+#define PFUZE100_SWxMODE_MASK 0xf
+#define PFUZE100_SWxMODE_APS_APS 0x8
+#define PFUZE100_SWxMODE_APS_OFF 0x4
+
+#define PFUZE100_VGENxLPWR BIT(6)
+#define PFUZE100_VGENxSTBY BIT(5)
+
enum chips { PFUZE100, PFUZE200, PFUZE3000 = 3 };

struct pfuze_regulator {
@@ -489,6 +503,69 @@ static inline struct device_node *match_of_node(int index)
}
#endif

+static struct pfuze_chip *syspm_pfuze_chip;
+
+static void pfuze_power_off_prepare(void)
+{
+ dev_info(syspm_pfuze_chip->dev, "Configure standy mode for power off");
+
+ /* Switch from default mode: APS/APS to APS/Off */
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_SW1ABMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_SW1CMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_SW2MODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_SW3AMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_SW3BMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_SW4MODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_VGEN1VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_VGEN2VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_VGEN3VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_VGEN4VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_VGEN5VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_update_bits(syspm_pfuze_chip->regmap, PFUZE100_VGEN6VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+}
+
+static int pfuze_power_off_prepare_init(struct pfuze_chip *pfuze_chip)
+{
+ if (pfuze_chip->chip_id != PFUZE100) {
+ dev_warn(pfuze_chip->dev, "Requested pm_power_off_prepare handler for not supported chip\n");
+ return -ENODEV;
+ }
+
+ if (pm_power_off_prepare) {
+ dev_warn(pfuze_chip->dev, "pm_power_off_prepare is already registered.\n");
+ return -EBUSY;
+ }
+
+ if (syspm_pfuze_chip) {
+ dev_warn(pfuze_chip->dev, "syspm_pfuze_chip is already set.\n");
+ return -EBUSY;
+ }
+
+ syspm_pfuze_chip = pfuze_chip;
+ pm_power_off_prepare = pfuze_power_off_prepare;
+
+ return 0;
+}
+
static int pfuze_identify(struct pfuze_chip *pfuze_chip)
{
unsigned int value;
@@ -659,6 +736,20 @@ static int pfuze100_regulator_probe(struct i2c_client *client,
}
}

+ if (of_property_read_bool(client->dev.of_node,
+ "fsl,pmic-stby-poweroff"))
+ return pfuze_power_off_prepare_init(pfuze_chip);
+
+ return 0;
+}
+
+static int pfuze100_regulator_remove(struct i2c_client *client)
+{
+ if (syspm_pfuze_chip) {
+ syspm_pfuze_chip = NULL;
+ pm_power_off_prepare = NULL;
+ }
+
return 0;
}

@@ -669,6 +760,7 @@ static struct i2c_driver pfuze_driver = {
.of_match_table = pfuze_dt_ids,
},
.probe = pfuze100_regulator_probe,
+ .remove = pfuze100_regulator_remove,
};
module_i2c_driver(pfuze_driver);

[Oleksij Rempel]

Export pm_power_off_prepare. It is needed to implement power off on
Freescale/NXP iMX6 based boards with external power management
integrated circuit (PMIC).

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
---
kernel/reboot.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/reboot.c b/kernel/reboot.c
index bd30a973fe94..a6903bf772c7 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -49,6 +49,7 @@ int reboot_force;
*/

void (*pm_power_off_prepare)(void);
+EXPORT_SYMBOL(pm_power_off_prepare);

/**
* emergency_restart - reboot the system

[Oleksij Rempel]

Hallo all,

Here Gentle Ping to the Old King

DT is already ACKed.

This patch series is providing power off support for Freescale/NXP iMX6 based
boards with external power management integrated circuit (PMIC).
- rename imx6_pm_poweroff to imx6_pm_stby_poweroff
- fix "MPIC_STBY_REQ" typo in the comment.
- remove useless includes from pm-imx6.c patch
- add Acked-by to "regulator: pfuze100: add fsl,pmic-stby-poweroff property"
patch
- update comment in "regulator: pfuze100: add fsl,pmic-stby-poweroff ..."
patch
- add Acked-by to "ARM: imx6q: provide documentation for new ..."
patch
- set pm_power_off_prepare = NULL on .remove.
- documentation and spelling fixes.
- use %pf instead of lookup_symbol_name.
ARM: imx6q: provide documentation for new fsl,pmic-stby-poweroff
property
ARM: imx6: register pm_power_off handler if "fsl,pmic-stby-poweroff"
is set
kernel/reboot.c: export pm_power_off_prepare
regulator: pfuze100: add fsl,pmic-stby-poweroff property
regulator: pfuze100-regulator: provide pm_power_off_prepare handler
ARM: dts: imx6: RIoTboard provide standby on power off option
.../devicetree/bindings/clock/imx6q-clock.txt | 8 ++
.../devicetree/bindings/regulator/pfuze100.txt | 7 ++
arch/arm/boot/dts/imx6dl-riotboard.dts | 5 ++
arch/arm/mach-imx/pm-imx6.c | 25 ++++++
drivers/regulator/pfuze100-regulator.c | 92 ++++++++++++++++++++++
kernel/reboot.c | 1 +
6 files changed, 138 insertions(+)

[Mark Brown]

Post by Oleksij Rempel
Hallo all,
Here Gentle Ping to the Old King
DT is already ACKed.

Please don't send content free pings and please allow a reasonable time
for review. People get busy, go on holiday, attend conferences and so
on so unless there is some reason for urgency (like critical bug fixes)
please allow at least a couple of weeks for review. If there have been
review comments then people may be waiting for those to be addressed.

Sending content free pings adds to the mail volume (if they are seen at
all) which is often the problem and since they can't be reviewed
directly if something has gone wrong you'll have to resend the patches
anyway, though there are some other maintainers who like them - if in
doubt look at how patches for the subsystem are normally handled.

[Russell King - ARM Linux]

Post by Mark Brown

Post by Oleksij Rempel
Hallo all,
Here Gentle Ping to the Old King
DT is already ACKed.

Please don't send content free pings and please allow a reasonable time
for review. People get busy, go on holiday, attend conferences and so
on so unless there is some reason for urgency (like critical bug fixes)
please allow at least a couple of weeks for review. If there have been
review comments then people may be waiting for those to be addressed.
Sending content free pings adds to the mail volume (if they are seen at
all) which is often the problem and since they can't be reviewed
directly if something has gone wrong you'll have to resend the patches
anyway, though there are some other maintainers who like them - if in
doubt look at how patches for the subsystem are normally handled.

It also doesn't help that there's little context about who Oleksij is
expecting a reply from. There's 11 individuals in the To: header.
Is the reference above refering to me? Shrug, I don't know. I doubt
it because I'm not maintaining the imx6 SoC support.