Adding upstream version 5.10.209.upstream/5.10.209upstream

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

1 files changed, 200 insertions, 0 deletions

diff --git a/drivers/leds/leds-regulator.c b/drivers/leds/leds-regulator.c
new file mode 100644
index 000000000..208c98918
--- /dev/null
+++ b/drivers/leds/leds-regulator.c
@@ -0,0 +1,200 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * leds-regulator.c - LED class driver for regulator driven LEDs.
+ *
+ * Copyright (C) 2009 Antonio Ospite <ospite@studenti.unina.it>
+ *
+ * Inspired by leds-wm8350 driver.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/leds.h>
+#include <linux/leds-regulator.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#define to_regulator_led(led_cdev) \
+	container_of(led_cdev, struct regulator_led, cdev)
+
+struct regulator_led {
+	struct led_classdev cdev;
+	int enabled;
+	struct mutex mutex;
+
+	struct regulator *vcc;
+};
+
+static inline int led_regulator_get_max_brightness(struct regulator *supply)
+{
+	int ret;
+	int voltage = regulator_list_voltage(supply, 0);
+
+	if (voltage <= 0)
+		return 1;
+
+	/* even if regulator can't change voltages,
+	 * we still assume it can change status
+	 * and the LED can be turned on and off.
+	 */
+	ret = regulator_set_voltage(supply, voltage, voltage);
+	if (ret < 0)
+		return 1;
+
+	return regulator_count_voltages(supply);
+}
+
+static int led_regulator_get_voltage(struct regulator *supply,
+		enum led_brightness brightness)
+{
+	if (brightness == 0)
+		return -EINVAL;
+
+	return regulator_list_voltage(supply, brightness - 1);
+}
+
+
+static void regulator_led_enable(struct regulator_led *led)
+{
+	int ret;
+
+	if (led->enabled)
+		return;
+
+	ret = regulator_enable(led->vcc);
+	if (ret != 0) {
+		dev_err(led->cdev.dev, "Failed to enable vcc: %d\n", ret);
+		return;
+	}
+
+	led->enabled = 1;
+}
+
+static void regulator_led_disable(struct regulator_led *led)
+{
+	int ret;
+
+	if (!led->enabled)
+		return;
+
+	ret = regulator_disable(led->vcc);
+	if (ret != 0) {
+		dev_err(led->cdev.dev, "Failed to disable vcc: %d\n", ret);
+		return;
+	}
+
+	led->enabled = 0;
+}
+
+static int regulator_led_brightness_set(struct led_classdev *led_cdev,
+					 enum led_brightness value)
+{
+	struct regulator_led *led = to_regulator_led(led_cdev);
+	int voltage;
+	int ret = 0;
+
+	mutex_lock(&led->mutex);
+
+	if (value == LED_OFF) {
+		regulator_led_disable(led);
+		goto out;
+	}
+
+	if (led->cdev.max_brightness > 1) {
+		voltage = led_regulator_get_voltage(led->vcc, value);
+		dev_dbg(led->cdev.dev, "brightness: %d voltage: %d\n",
+				value, voltage);
+
+		ret = regulator_set_voltage(led->vcc, voltage, voltage);
+		if (ret != 0)
+			dev_err(led->cdev.dev, "Failed to set voltage %d: %d\n",
+				voltage, ret);
+	}
+
+	regulator_led_enable(led);
+
+out:
+	mutex_unlock(&led->mutex);
+	return ret;
+}
+
+static int regulator_led_probe(struct platform_device *pdev)
+{
+	struct led_regulator_platform_data *pdata =
+			dev_get_platdata(&pdev->dev);
+	struct regulator_led *led;
+	struct regulator *vcc;
+	int ret = 0;
+
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "no platform data\n");
+		return -ENODEV;
+	}
+
+	vcc = devm_regulator_get_exclusive(&pdev->dev, "vled");
+	if (IS_ERR(vcc)) {
+		dev_err(&pdev->dev, "Cannot get vcc for %s\n", pdata->name);
+		return PTR_ERR(vcc);
+	}
+
+	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
+	if (led == NULL)
+		return -ENOMEM;
+
+	led->cdev.max_brightness = led_regulator_get_max_brightness(vcc);
+	if (pdata->brightness > led->cdev.max_brightness) {
+		dev_err(&pdev->dev, "Invalid default brightness %d\n",
+				pdata->brightness);
+		return -EINVAL;
+	}
+
+	led->cdev.brightness_set_blocking = regulator_led_brightness_set;
+	led->cdev.name = pdata->name;
+	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
+	led->vcc = vcc;
+
+	/* to handle correctly an already enabled regulator */
+	if (regulator_is_enabled(led->vcc))
+		led->enabled = 1;
+
+	mutex_init(&led->mutex);
+
+	platform_set_drvdata(pdev, led);
+
+	ret = led_classdev_register(&pdev->dev, &led->cdev);
+	if (ret < 0)
+		return ret;
+
+	/* to expose the default value to userspace */
+	led->cdev.brightness = pdata->brightness;
+
+	/* Set the default led status */
+	regulator_led_brightness_set(&led->cdev, led->cdev.brightness);
+
+	return 0;
+}
+
+static int regulator_led_remove(struct platform_device *pdev)
+{
+	struct regulator_led *led = platform_get_drvdata(pdev);
+
+	led_classdev_unregister(&led->cdev);
+	regulator_led_disable(led);
+	return 0;
+}
+
+static struct platform_driver regulator_led_driver = {
+	.driver = {
+		   .name  = "leds-regulator",
+		   },
+	.probe  = regulator_led_probe,
+	.remove = regulator_led_remove,
+};
+
+module_platform_driver(regulator_led_driver);
+
+MODULE_AUTHOR("Antonio Ospite <ospite@studenti.unina.it>");
+MODULE_DESCRIPTION("Regulator driven LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:leds-regulator");