Changes in v2:
- rename DT node
Changes in v3:
- add regulator-poweroff driver
- use regulator-poweroff driver instead of gpio-poweroff
Changes in v4:
- hardcode poweroff timeout to 3000ms, not configurable any more
- remove support for multiple regulators
- fix Documentation issues
Michael Klein (3):
power: reset: new driver regulator-poweroff
Documentation: DT: binding documentation for regulator-poweroff
ARM: dts: sun8i-h2-plus-bananapi-m2-zero: add poweroff node
.../power/reset/regulator-poweroff.yaml | 37 ++++++++
.../dts/sun8i-h2-plus-bananapi-m2-zero.dts | 5 ++
drivers/power/reset/Kconfig | 7 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/regulator-poweroff.c | 86 +++++++++++++++++++
5 files changed, 136 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power/reset/regulator-poweroff.yaml
create mode 100644 drivers/power/reset/regulator-poweroff.c
--
2.29.2
Add add devicetree information for the regulator-poweroff driver.
Signed-off-by: Michael Klein <[email protected]>
---
This patch depends on the regulator names added in
arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts b/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts
index b43028f9e6df..e7370a049ce2 100644
--- a/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts
+++ b/arch/arm/boot/dts/sun8i-h2-plus-bananapi-m2-zero.dts
@@ -86,6 +86,11 @@ reg_vcc1v2: vcc1v2 {
vin-supply = <®_vcc5v0>;
};
+ poweroff {
+ compatible = "regulator-poweroff";
+ power-supply = <®_vcc1v2>;
+ };
+
wifi_pwrseq: wifi_pwrseq {
compatible = "mmc-pwrseq-simple";
reset-gpios = <&r_pio 0 7 GPIO_ACTIVE_LOW>; /* PL7 */
--
2.29.2
This driver registers a pm_power_off function to disable a set of
regulators defined in the devicetree to turn off the board.
Signed-off-by: Michael Klein <[email protected]>
---
drivers/power/reset/Kconfig | 7 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/regulator-poweroff.c | 86 ++++++++++++++++++++++++
3 files changed, 94 insertions(+)
create mode 100644 drivers/power/reset/regulator-poweroff.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index d55b3727e00e..b22c4fdb2561 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -177,6 +177,13 @@ config POWER_RESET_QNAP
Say Y if you have a QNAP NAS.
+config POWER_RESET_REGULATOR
+ bool "Regulator subsystem power-off driver"
+ depends on OF && REGULATOR
+ help
+ This driver supports turning off your board by disabling a
+ power regulator defined in the devicetree.
+
config POWER_RESET_RESTART
bool "Restart power-off driver"
help
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index c51eceba9ea3..9dc49d3a57ff 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_POWER_RESET_OCELOT_RESET) += ocelot-reset.o
obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o
obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o
obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
+obj-$(CONFIG_POWER_RESET_REGULATOR) += regulator-poweroff.o
obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o
obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
diff --git a/drivers/power/reset/regulator-poweroff.c b/drivers/power/reset/regulator-poweroff.c
new file mode 100644
index 000000000000..c67136cd7b90
--- /dev/null
+++ b/drivers/power/reset/regulator-poweroff.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Force-disables a regulator to power down a device
+ *
+ * Michael Klein <[email protected]>
+ *
+ * Copyright (C) 2020 Michael Klein
+ *
+ * Based on the gpio-poweroff driver.
+ */
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/regulator/consumer.h>
+
+#define TIMEOUT_MS 3000
+
+/*
+ * Hold configuration here, cannot be more than one instance of the driver
+ * since pm_power_off itself is global.
+ */
+static struct regulator *poweroff_regulator;
+
+static void regulator_poweroff_do_poweroff(void)
+{
+ if (poweroff_regulator && regulator_is_enabled(poweroff_regulator))
+ regulator_force_disable(poweroff_regulator);
+
+ /* give it some time */
+ mdelay(TIMEOUT_MS);
+
+ WARN_ON(1);
+}
+
+static int regulator_poweroff_probe(struct platform_device *pdev)
+{
+ struct regulator *regulator;
+
+ /* If a pm_power_off function has already been added, leave it alone */
+ if (pm_power_off != NULL) {
+ dev_err(&pdev->dev,
+ "%s: pm_power_off function already registered\n",
+ __func__);
+ return -EBUSY;
+ }
+
+ regulator = devm_regulator_get(&pdev->dev, "power");
+ if (IS_ERR(regulator))
+ return PTR_ERR(regulator);
+
+ poweroff_regulator = regulator;
+
+ pm_power_off = ®ulator_poweroff_do_poweroff;
+ return 0;
+}
+
+static int regulator_poweroff_remove(__maybe_unused struct platform_device *pdev)
+{
+ if (pm_power_off == ®ulator_poweroff_do_poweroff)
+ pm_power_off = NULL;
+
+ return 0;
+}
+
+static const struct of_device_id of_regulator_poweroff_match[] = {
+ { .compatible = "regulator-poweroff", },
+ {},
+};
+
+static struct platform_driver regulator_poweroff_driver = {
+ .probe = regulator_poweroff_probe,
+ .remove = regulator_poweroff_remove,
+ .driver = {
+ .name = "poweroff-regulator",
+ .of_match_table = of_regulator_poweroff_match,
+ },
+};
+
+module_platform_driver(regulator_poweroff_driver);
+
+MODULE_AUTHOR("Michael Klein <[email protected]>");
+MODULE_DESCRIPTION("Regulator poweroff driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:poweroff-regulator");
--
2.29.2
Add devicetree binding documentation for regulator-poweroff driver.
Signed-off-by: Michael Klein <[email protected]>
---
.../power/reset/regulator-poweroff.yaml | 37 +++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power/reset/regulator-poweroff.yaml
diff --git a/Documentation/devicetree/bindings/power/reset/regulator-poweroff.yaml b/Documentation/devicetree/bindings/power/reset/regulator-poweroff.yaml
new file mode 100644
index 000000000000..c74ac247ab70
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/reset/regulator-poweroff.yaml
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/power/reset/regulator-poweroff.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Force-disable power regulator to turn the power off.
+
+maintainers:
+ - Michael Klein <[email protected]>
+
+description: |
+ When the power-off handler is called, a power regulator is disabled by
+ calling regulator_force_disable(). If the power is still on and the
+ CPU still running after a 3000ms delay, a warning is emitted.
+
+properties:
+ compatible:
+ const: "regulator-poweroff"
+
+ power-supply:
+ description:
+ regulator to disable on power-down
+
+required:
+ - compatible
+ - power-supply
+
+additionalProperties: false
+
+examples:
+ - |
+ regulator-poweroff {
+ compatible = "regulator-poweroff";
+ power-supply = <®_vcc1v2>;
+ };
+...
--
2.29.2
On Wed, 09 Dec 2020 22:02:20 +0100, Michael Klein wrote:
> Add devicetree binding documentation for regulator-poweroff driver.
>
> Signed-off-by: Michael Klein <[email protected]>
> ---
> .../power/reset/regulator-poweroff.yaml | 37 +++++++++++++++++++
> 1 file changed, 37 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/power/reset/regulator-poweroff.yaml
>
Reviewed-by: Rob Herring <[email protected]>