Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 407 insertions, 0 deletions

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
new file mode 100644
index 000000000..2aff6db74
--- /dev/null
+++ b/drivers/regulator/pwm-regulator.c
@@ -0,0 +1,407 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Regulator driver for PWM Regulators
+ *
+ * Copyright (C) 2014 - STMicroelectronics Inc.
+ *
+ * Author: Lee Jones <lee.jones@linaro.org>
+ */
+
+#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/pwm.h>
+#include <linux/gpio/consumer.h>
+
+struct pwm_continuous_reg_data {
+	unsigned int min_uV_dutycycle;
+	unsigned int max_uV_dutycycle;
+	unsigned int dutycycle_unit;
+};
+
+struct pwm_regulator_data {
+	/*  Shared */
+	struct pwm_device *pwm;
+
+	/* Voltage table */
+	struct pwm_voltages *duty_cycle_table;
+
+	/* Continuous mode info */
+	struct pwm_continuous_reg_data continuous;
+
+	/* regulator descriptor */
+	struct regulator_desc desc;
+
+	int state;
+
+	/* Enable GPIO */
+	struct gpio_desc *enb_gpio;
+};
+
+struct pwm_voltages {
+	unsigned int uV;
+	unsigned int dutycycle;
+};
+
+/*
+ * Voltage table call-backs
+ */
+static void pwm_regulator_init_state(struct regulator_dev *rdev)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+	struct pwm_state pwm_state;
+	unsigned int dutycycle;
+	int i;
+
+	pwm_get_state(drvdata->pwm, &pwm_state);
+	dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);
+
+	for (i = 0; i < rdev->desc->n_voltages; i++) {
+		if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
+			drvdata->state = i;
+			return;
+		}
+	}
+}
+
+static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+
+	if (drvdata->state < 0)
+		pwm_regulator_init_state(rdev);
+
+	return drvdata->state;
+}
+
+static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
+					 unsigned selector)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+	struct pwm_state pstate;
+	int ret;
+
+	pwm_init_state(drvdata->pwm, &pstate);
+	pwm_set_relative_duty_cycle(&pstate,
+			drvdata->duty_cycle_table[selector].dutycycle, 100);
+
+	ret = pwm_apply_state(drvdata->pwm, &pstate);
+	if (ret) {
+		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
+		return ret;
+	}
+
+	drvdata->state = selector;
+
+	return 0;
+}
+
+static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
+				      unsigned selector)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+
+	if (selector >= rdev->desc->n_voltages)
+		return -EINVAL;
+
+	return drvdata->duty_cycle_table[selector].uV;
+}
+
+static int pwm_regulator_enable(struct regulator_dev *dev)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+
+	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
+
+	return pwm_enable(drvdata->pwm);
+}
+
+static int pwm_regulator_disable(struct regulator_dev *dev)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+
+	pwm_disable(drvdata->pwm);
+
+	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
+
+	return 0;
+}
+
+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);
+}
+
+static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
+	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
+	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
+	int min_uV = rdev->constraints->min_uV;
+	int max_uV = rdev->constraints->max_uV;
+	int diff_uV = max_uV - min_uV;
+	struct pwm_state pstate;
+	unsigned int diff_duty;
+	unsigned int voltage;
+
+	pwm_get_state(drvdata->pwm, &pstate);
+
+	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
+
+	/*
+	 * The dutycycle for min_uV might be greater than the one for max_uV.
+	 * This is happening when the user needs an inversed polarity, but the
+	 * PWM device does not support inversing it in hardware.
+	 */
+	if (max_uV_duty < min_uV_duty) {
+		voltage = min_uV_duty - voltage;
+		diff_duty = min_uV_duty - max_uV_duty;
+	} else {
+		voltage = voltage - min_uV_duty;
+		diff_duty = max_uV_duty - min_uV_duty;
+	}
+
+	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
+
+	return voltage + min_uV;
+}
+
+static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
+				     int req_min_uV, int req_max_uV,
+				     unsigned int *selector)
+{
+	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
+	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
+	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
+	int min_uV = rdev->constraints->min_uV;
+	int max_uV = rdev->constraints->max_uV;
+	int diff_uV = max_uV - min_uV;
+	struct pwm_state pstate;
+	unsigned int diff_duty;
+	unsigned int dutycycle;
+	int ret;
+
+	pwm_init_state(drvdata->pwm, &pstate);
+
+	/*
+	 * The dutycycle for min_uV might be greater than the one for max_uV.
+	 * This is happening when the user needs an inversed polarity, but the
+	 * PWM device does not support inversing it in hardware.
+	 */
+	if (max_uV_duty < min_uV_duty)
+		diff_duty = min_uV_duty - max_uV_duty;
+	else
+		diff_duty = max_uV_duty - min_uV_duty;
+
+	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
+					  diff_duty,
+					  diff_uV);
+
+	if (max_uV_duty < min_uV_duty)
+		dutycycle = min_uV_duty - dutycycle;
+	else
+		dutycycle = min_uV_duty + dutycycle;
+
+	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
+
+	ret = pwm_apply_state(drvdata->pwm, &pstate);
+	if (ret) {
+		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+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,
+	.map_voltage     = regulator_map_voltage_iterate,
+	.enable          = pwm_regulator_enable,
+	.disable         = pwm_regulator_disable,
+	.is_enabled      = pwm_regulator_is_enabled,
+};
+
+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,
+	.disable         = pwm_regulator_disable,
+	.is_enabled      = pwm_regulator_is_enabled,
+};
+
+static const struct regulator_desc pwm_regulator_desc = {
+	.name		= "pwm-regulator",
+	.type		= REGULATOR_VOLTAGE,
+	.owner		= THIS_MODULE,
+	.supply_name    = "pwm",
+};
+
+static int pwm_regulator_init_table(struct platform_device *pdev,
+				    struct pwm_regulator_data *drvdata)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct pwm_voltages *duty_cycle_table;
+	unsigned int length = 0;
+	int ret;
+
+	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;
+	}
+
+	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
+	if (!duty_cycle_table)
+		return -ENOMEM;
+
+	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;
+	}
+
+	drvdata->state			= -ENOTRECOVERABLE;
+	drvdata->duty_cycle_table	= duty_cycle_table;
+	drvdata->desc.ops = &pwm_regulator_voltage_table_ops;
+	drvdata->desc.n_voltages	= length / sizeof(*duty_cycle_table);
+
+	return 0;
+}
+
+static int pwm_regulator_init_continuous(struct platform_device *pdev,
+					 struct pwm_regulator_data *drvdata)
+{
+	u32 dutycycle_range[2] = { 0, 100 };
+	u32 dutycycle_unit = 100;
+
+	drvdata->desc.ops = &pwm_regulator_voltage_continuous_ops;
+	drvdata->desc.continuous_voltage_range = true;
+
+	of_property_read_u32_array(pdev->dev.of_node,
+				   "pwm-dutycycle-range",
+				   dutycycle_range, 2);
+	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
+			     &dutycycle_unit);
+
+	if (dutycycle_range[0] > dutycycle_unit ||
+	    dutycycle_range[1] > dutycycle_unit)
+		return -EINVAL;
+
+	drvdata->continuous.dutycycle_unit = dutycycle_unit;
+	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
+	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
+
+	return 0;
+}
+
+static int pwm_regulator_probe(struct platform_device *pdev)
+{
+	const struct regulator_init_data *init_data;
+	struct pwm_regulator_data *drvdata;
+	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) {
+		dev_err(&pdev->dev, "Device Tree node missing\n");
+		return -EINVAL;
+	}
+
+	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata)
+		return -ENOMEM;
+
+	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
+
+	if (of_property_present(np, "voltage-table"))
+		ret = pwm_regulator_init_table(pdev, drvdata);
+	else
+		ret = pwm_regulator_init_continuous(pdev, drvdata);
+	if (ret)
+		return ret;
+
+	init_data = of_get_regulator_init_data(&pdev->dev, np,
+					       &drvdata->desc);
+	if (!init_data)
+		return -ENOMEM;
+
+	config.of_node = np;
+	config.dev = &pdev->dev;
+	config.driver_data = drvdata;
+	config.init_data = init_data;
+
+	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
+	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;
+	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;
+	}
+
+	ret = pwm_adjust_config(drvdata->pwm);
+	if (ret)
+		return ret;
+
+	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 0;
+}
+
+static const struct of_device_id __maybe_unused pwm_of_match[] = {
+	{ .compatible = "pwm-regulator" },
+	{ },
+};
+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,
+};
+
+module_platform_driver(pwm_regulator_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
+MODULE_DESCRIPTION("PWM Regulator Driver");
+MODULE_ALIAS("platform:pwm-regulator");