Merge tag 'regulator-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie...

[sfrench/cifs-2.6.git] / drivers / regulator / pwm-regulator.c

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index fafa3488e960520752b44b482864401925a22a6f..666bc3bb52ef83790df5df9afab68306a39d766a 100644 (file)
--- 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);
 }
 
@@ -132,6 +145,7 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
        unsigned int duty_pulse;
        u64 req_period;
        u32 rem;
+       int old_uV = pwm_regulator_get_voltage(rdev);
        int ret;
 
        pwm_get_args(drvdata->pwm, &pargs);
@@ -159,15 +173,14 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
                return ret;
        }
 
-       ret = pwm_enable(drvdata->pwm);
-       if (ret) {
-               dev_err(&rdev->dev, "Failed to enable PWM: %d\n", ret);
-               return ret;
-       }
        drvdata->volt_uV = min_uV;
 
-       /* Delay required by PWM regulator to settle to the new voltage */
-       usleep_range(ramp_delay, ramp_delay + 1000);
+       if ((ramp_delay == 0) || !pwm_regulator_is_enabled(rdev))
+               return 0;
+
+       /* Ramp delay is in uV/uS. Adjust to uS and delay */
+       ramp_delay = DIV_ROUND_UP(abs(min_uV - old_uV), ramp_delay);
+       usleep_range(ramp_delay, ramp_delay + DIV_ROUND_UP(ramp_delay, 10));
 
        return 0;
 }
@@ -253,6 +266,7 @@ 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) {
@@ -290,6 +304,18 @@ 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.