1 files changed, 55 insertions, 18 deletions

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index 698c420e0869..7434b6b22d32 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -157,7 +157,17 @@ static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
 
 	pwm_get_state(drvdata->pwm, &pstate);
 
+	if (!pstate.enabled) {
+		if (pstate.polarity == PWM_POLARITY_INVERSED)
+			pstate.duty_cycle = pstate.period;
+		else
+			pstate.duty_cycle = 0;
+	}
+
 	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
+	if (voltage < min(max_uV_duty, min_uV_duty) ||
+	    voltage > max(max_uV_duty, min_uV_duty))
+		return -ENOTRECOVERABLE;
 
 	/*
 	 * The dutycycle for min_uV might be greater than the one for max_uV.
@@ -261,11 +271,10 @@ static int pwm_regulator_init_table(struct platform_device *pdev,
 	of_find_property(np, "voltage-table", &length);
 
 	if ((length < sizeof(*duty_cycle_table)) ||
-	    (length % sizeof(*duty_cycle_table))) {
-		dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
-			length);
-		return -EINVAL;
-	}
+	    (length % sizeof(*duty_cycle_table)))
+		return dev_err_probe(&pdev->dev, -EINVAL,
+				     "voltage-table length(%d) is invalid\n",
+				     length);
 
 	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
 	if (!duty_cycle_table)
@@ -274,10 +283,9 @@ static int pwm_regulator_init_table(struct platform_device *pdev,
 	ret = of_property_read_u32_array(np, "voltage-table",
 					 (u32 *)duty_cycle_table,
 					 length / sizeof(u32));
-	if (ret) {
-		dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
-		return ret;
-	}
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to read voltage-table\n");
 
 	drvdata->state			= -ENOTRECOVERABLE;
 	drvdata->duty_cycle_table	= duty_cycle_table;
@@ -313,6 +321,32 @@ static int pwm_regulator_init_continuous(struct platform_device *pdev,
 	return 0;
 }
 
+static int pwm_regulator_init_boot_on(struct platform_device *pdev,
+				      struct pwm_regulator_data *drvdata,
+				      const struct regulator_init_data *init_data)
+{
+	struct pwm_state pstate;
+
+	if (!init_data->constraints.boot_on || drvdata->enb_gpio)
+		return 0;
+
+	pwm_get_state(drvdata->pwm, &pstate);
+	if (pstate.enabled)
+		return 0;
+
+	/*
+	 * Update the duty cycle so the output does not change
+	 * when the regulator core enables the regulator (and
+	 * thus the PWM channel).
+	 */
+	if (pstate.polarity == PWM_POLARITY_INVERSED)
+		pstate.duty_cycle = pstate.period;
+	else
+		pstate.duty_cycle = 0;
+
+	return pwm_apply_might_sleep(drvdata->pwm, &pstate);
+}
+
 static int pwm_regulator_probe(struct platform_device *pdev)
 {
 	const struct regulator_init_data *init_data;
@@ -323,10 +357,9 @@ static int pwm_regulator_probe(struct platform_device *pdev)
 	enum gpiod_flags gpio_flags;
 	int ret;
 
-	if (!np) {
-		dev_err(&pdev->dev, "Device Tree node missing\n");
-		return -EINVAL;
-	}
+	if (!np)
+		return dev_err_probe(&pdev->dev, -EINVAL,
+				     "Device Tree node missing\n");
 
 	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
 	if (!drvdata)
@@ -364,21 +397,25 @@ static int pwm_regulator_probe(struct platform_device *pdev)
 						    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;
+		return dev_err_probe(&pdev->dev, ret, "Failed to get enable GPIO\n");
 	}
 
 	ret = pwm_adjust_config(drvdata->pwm);
 	if (ret)
 		return ret;
 
+	ret = pwm_regulator_init_boot_on(pdev, drvdata, init_data);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to apply boot_on settings\n");
+
 	regulator = devm_regulator_register(&pdev->dev,
 					    &drvdata->desc, &config);
 	if (IS_ERR(regulator)) {
 		ret = PTR_ERR(regulator);
-		dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
-			drvdata->desc.name, ret);
-		return ret;
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to register regulator %s\n",
+				     drvdata->desc.name);
 	}
 
 	return 0;