Add an optional enable GPIO to the pwm-regulator driver.
Signed-off-by: Alexandre Courbot <acour...@nvidia.com>
---
Changes since v1:
- Do not try to be smart and use the core enable GPIO as this introduces an
incompatible behavior. Probe and manipulate the GPIO in pwm-regulator.
- Use standard enable-gpios name for GPIO property
.../bindings/regulator/pwm-regulator.txt | 7 +++++-
drivers/regulator/pwm-regulator.c | 26 ++++++++++++++++++++++
2 files changed, 32 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
index ed936f0f34f2..dd6f59cf1455 100644
--- a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
+++ b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt
@@ -38,13 +38,18 @@ NB: To be clear, if voltage-table is provided, then the
device will be used
in Voltage Table Mode. If no voltage-table is provided, then the device will
be used in Continuous Voltage Mode.
+Optional properties:
+--------------------
+- enable-gpios: GPIO to use to enable/disable the regulator
+
Any property defined as part of the core regulator binding can also be used.
(See: ../regulator/regulator.txt)
-Continuous Voltage Example:
+Continuous Voltage With Enable GPIO Example:
pwm_regulator {
compatible = "pwm-regulator;
pwms = <&pwm1 0 8448 0>;
+ enable-gpios = <&gpio0 23 GPIO_ACTIVE_HIGH>;
regulator-min-microvolt = <1016000>;
regulator-max-microvolt = <1114000>;
regulator-name = "vdd_logic";
diff --git a/drivers/regulator/pwm-regulator.c
b/drivers/regulator/pwm-regulator.c
index ab3cc0235843..90f8b7fd0437 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -20,6 +20,7 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pwm.h>
+#include <linux/gpio/consumer.h>
struct pwm_regulator_data {
/* Shared */
@@ -38,6 +39,9 @@ struct pwm_regulator_data {
/* Continuous voltage */
int volt_uV;
+
+ /* Enable GPIO */
+ struct gpio_desc *enb_gpio;
};
struct pwm_voltages {
@@ -94,6 +98,9 @@ static int pwm_regulator_enable(struct regulator_dev *dev)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ if (drvdata->enb_gpio)
+ gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
+
return pwm_enable(drvdata->pwm);
}
@@ -103,6 +110,9 @@ static int pwm_regulator_disable(struct regulator_dev *dev)
pwm_disable(drvdata->pwm);
+ if (drvdata->enb_gpio)
+ gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
+
return 0;
}
@@ -110,6 +120,9 @@ static int pwm_regulator_is_enabled(struct regulator_dev
*dev)
{
struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+ if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
+ return false;
+
return pwm_is_enabled(drvdata->pwm);
}
@@ -248,6 +261,7 @@ static int pwm_regulator_probe(struct platform_device *pdev)
struct regulator_dev *regulator;
struct regulator_config config = { };
struct device_node *np = pdev->dev.of_node;
+ enum gpiod_flags gpio_flags;
int ret;
if (!np) {
@@ -285,6 +299,18 @@ static int pwm_regulator_probe(struct platform_device
*pdev)
return ret;
}
+ if (init_data->constraints.boot_on || init_data->constraints.always_on)
+ gpio_flags = GPIOD_OUT_HIGH;
+ else
+ gpio_flags = GPIOD_OUT_LOW;
+ drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
+ gpio_flags);
+ if (IS_ERR(drvdata->enb_gpio)) {
+ ret = PTR_ERR(drvdata->enb_gpio);
+ dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
+ return ret;
+ }
+
/*
* FIXME: pwm_apply_args() should be removed when switching to the
* atomic PWM API.
--
2.8.3
