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path: root/drivers/regulator/pwm-regulator.c
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Diffstat (limited to 'drivers/regulator/pwm-regulator.c')
-rw-r--r--drivers/regulator/pwm-regulator.c118
1 files changed, 72 insertions, 46 deletions
diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index a2fd140eff81..7434b6b22d32 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -1,23 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Regulator driver for PWM Regulators
*
* Copyright (C) 2014 - STMicroelectronics Inc.
*
* Author: Lee Jones <lee.jones@linaro.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
+#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/of.h>
-#include <linux/of_device.h>
#include <linux/pwm.h>
#include <linux/gpio/consumer.h>
@@ -40,9 +37,6 @@ struct pwm_regulator_data {
/* regulator descriptor */
struct regulator_desc desc;
- /* Regulator ops */
- struct regulator_ops ops;
-
int state;
/* Enable GPIO */
@@ -54,7 +48,7 @@ struct pwm_voltages {
unsigned int dutycycle;
};
-/**
+/*
* Voltage table call-backs
*/
static void pwm_regulator_init_state(struct regulator_dev *rdev)
@@ -96,7 +90,7 @@ static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
pwm_set_relative_duty_cycle(&pstate,
drvdata->duty_cycle_table[selector].dutycycle, 100);
- ret = pwm_apply_state(drvdata->pwm, &pstate);
+ ret = pwm_apply_might_sleep(drvdata->pwm, &pstate);
if (ret) {
dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
return ret;
@@ -163,7 +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.
@@ -222,7 +226,7 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
- ret = pwm_apply_state(drvdata->pwm, &pstate);
+ ret = pwm_apply_might_sleep(drvdata->pwm, &pstate);
if (ret) {
dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
return ret;
@@ -231,7 +235,7 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
return 0;
}
-static struct regulator_ops pwm_regulator_voltage_table_ops = {
+static const struct regulator_ops pwm_regulator_voltage_table_ops = {
.set_voltage_sel = pwm_regulator_set_voltage_sel,
.get_voltage_sel = pwm_regulator_get_voltage_sel,
.list_voltage = pwm_regulator_list_voltage,
@@ -241,7 +245,7 @@ static struct regulator_ops pwm_regulator_voltage_table_ops = {
.is_enabled = pwm_regulator_is_enabled,
};
-static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
+static const struct regulator_ops pwm_regulator_voltage_continuous_ops = {
.get_voltage = pwm_regulator_get_voltage,
.set_voltage = pwm_regulator_set_voltage,
.enable = pwm_regulator_enable,
@@ -249,7 +253,7 @@ static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
.is_enabled = pwm_regulator_is_enabled,
};
-static struct regulator_desc pwm_regulator_desc = {
+static const struct regulator_desc pwm_regulator_desc = {
.name = "pwm-regulator",
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
@@ -267,11 +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)
@@ -280,16 +283,13 @@ 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 = -EINVAL;
+ drvdata->state = -ENOTRECOVERABLE;
drvdata->duty_cycle_table = duty_cycle_table;
- memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
- sizeof(drvdata->ops));
- drvdata->desc.ops = &drvdata->ops;
+ drvdata->desc.ops = &pwm_regulator_voltage_table_ops;
drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
return 0;
@@ -301,9 +301,7 @@ static int pwm_regulator_init_continuous(struct platform_device *pdev,
u32 dutycycle_range[2] = { 0, 100 };
u32 dutycycle_unit = 100;
- memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
- sizeof(drvdata->ops));
- drvdata->desc.ops = &drvdata->ops;
+ drvdata->desc.ops = &pwm_regulator_voltage_continuous_ops;
drvdata->desc.continuous_voltage_range = true;
of_property_read_u32_array(pdev->dev.of_node,
@@ -323,6 +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;
@@ -333,10 +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)
@@ -344,7 +367,7 @@ static int pwm_regulator_probe(struct platform_device *pdev)
memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
- if (of_find_property(np, "voltage-table", NULL))
+ if (of_property_present(np, "voltage-table"))
ret = pwm_regulator_init_table(pdev, drvdata);
else
ret = pwm_regulator_init_continuous(pdev, drvdata);
@@ -362,11 +385,9 @@ static int pwm_regulator_probe(struct platform_device *pdev)
config.init_data = init_data;
drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
- if (IS_ERR(drvdata->pwm)) {
- ret = PTR_ERR(drvdata->pwm);
- dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
- return ret;
- }
+ if (IS_ERR(drvdata->pwm))
+ return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->pwm),
+ "Failed to get PWM\n");
if (init_data->constraints.boot_on || init_data->constraints.always_on)
gpio_flags = GPIOD_OUT_HIGH;
@@ -376,27 +397,31 @@ 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;
}
-static const struct of_device_id pwm_of_match[] = {
+static const struct of_device_id __maybe_unused pwm_of_match[] = {
{ .compatible = "pwm-regulator" },
{ },
};
@@ -405,6 +430,7 @@ MODULE_DEVICE_TABLE(of, pwm_of_match);
static struct platform_driver pwm_regulator_driver = {
.driver = {
.name = "pwm-regulator",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = of_match_ptr(pwm_of_match),
},
.probe = pwm_regulator_probe,
generated by cgit (git 2.34.1) at 2025-12-22 09:35:03 +0000