Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 217 insertions, 0 deletions

diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c
new file mode 100644
index 000000000..2b3bf1353
--- /dev/null
+++ b/drivers/leds/leds-pwm.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/drivers/leds-pwm.c
+ *
+ * simple PWM based LED control
+ *
+ * Copyright 2009 Luotao Fu @ Pengutronix (l.fu@pengutronix.de)
+ *
+ * based on leds-gpio.c by Raphael Assenat <raph@8d.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/leds.h>
+#include <linux/err.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include "leds.h"
+
+struct led_pwm {
+	const char	*name;
+	u8		active_low;
+	u8		default_state;
+	unsigned int	max_brightness;
+};
+
+struct led_pwm_data {
+	struct led_classdev	cdev;
+	struct pwm_device	*pwm;
+	struct pwm_state	pwmstate;
+	unsigned int		active_low;
+};
+
+struct led_pwm_priv {
+	int num_leds;
+	struct led_pwm_data leds[];
+};
+
+static int led_pwm_set(struct led_classdev *led_cdev,
+		       enum led_brightness brightness)
+{
+	struct led_pwm_data *led_dat =
+		container_of(led_cdev, struct led_pwm_data, cdev);
+	unsigned int max = led_dat->cdev.max_brightness;
+	unsigned long long duty = led_dat->pwmstate.period;
+
+	duty *= brightness;
+	do_div(duty, max);
+
+	if (led_dat->active_low)
+		duty = led_dat->pwmstate.period - duty;
+
+	led_dat->pwmstate.duty_cycle = duty;
+	led_dat->pwmstate.enabled = true;
+	return pwm_apply_state(led_dat->pwm, &led_dat->pwmstate);
+}
+
+__attribute__((nonnull))
+static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
+		       struct led_pwm *led, struct fwnode_handle *fwnode)
+{
+	struct led_pwm_data *led_data = &priv->leds[priv->num_leds];
+	struct led_init_data init_data = { .fwnode = fwnode };
+	int ret;
+
+	led_data->active_low = led->active_low;
+	led_data->cdev.name = led->name;
+	led_data->cdev.brightness = LED_OFF;
+	led_data->cdev.max_brightness = led->max_brightness;
+	led_data->cdev.flags = LED_CORE_SUSPENDRESUME;
+
+	led_data->pwm = devm_fwnode_pwm_get(dev, fwnode, NULL);
+	if (IS_ERR(led_data->pwm))
+		return dev_err_probe(dev, PTR_ERR(led_data->pwm),
+				     "unable to request PWM for %s\n",
+				     led->name);
+
+	led_data->cdev.brightness_set_blocking = led_pwm_set;
+
+	/* init PWM state */
+	switch (led->default_state) {
+	case LEDS_DEFSTATE_KEEP:
+		pwm_get_state(led_data->pwm, &led_data->pwmstate);
+		if (led_data->pwmstate.period)
+			break;
+		led->default_state = LEDS_DEFSTATE_OFF;
+		dev_warn(dev,
+			"failed to read period for %s, default to off",
+			led->name);
+		fallthrough;
+	default:
+		pwm_init_state(led_data->pwm, &led_data->pwmstate);
+		break;
+	}
+
+	/* set brightness */
+	switch (led->default_state) {
+	case LEDS_DEFSTATE_ON:
+		led_data->cdev.brightness = led->max_brightness;
+		break;
+	case LEDS_DEFSTATE_KEEP:
+		{
+		uint64_t brightness;
+
+		brightness = led->max_brightness;
+		brightness *= led_data->pwmstate.duty_cycle;
+		do_div(brightness, led_data->pwmstate.period);
+		led_data->cdev.brightness = brightness;
+		}
+		break;
+	}
+
+	ret = devm_led_classdev_register_ext(dev, &led_data->cdev, &init_data);
+	if (ret) {
+		dev_err(dev, "failed to register PWM led for %s: %d\n",
+			led->name, ret);
+		return ret;
+	}
+
+	if (led->default_state != LEDS_DEFSTATE_KEEP) {
+		ret = led_pwm_set(&led_data->cdev, led_data->cdev.brightness);
+		if (ret) {
+			dev_err(dev, "failed to set led PWM value for %s: %d",
+				led->name, ret);
+			return ret;
+		}
+	}
+
+	priv->num_leds++;
+	return 0;
+}
+
+static int led_pwm_create_fwnode(struct device *dev, struct led_pwm_priv *priv)
+{
+	struct fwnode_handle *fwnode;
+	struct led_pwm led;
+	int ret;
+
+	device_for_each_child_node(dev, fwnode) {
+		memset(&led, 0, sizeof(led));
+
+		ret = fwnode_property_read_string(fwnode, "label", &led.name);
+		if (ret && is_of_node(fwnode))
+			led.name = to_of_node(fwnode)->name;
+
+		if (!led.name) {
+			ret = -EINVAL;
+			goto err_child_out;
+		}
+
+		led.active_low = fwnode_property_read_bool(fwnode,
+							   "active-low");
+		fwnode_property_read_u32(fwnode, "max-brightness",
+					 &led.max_brightness);
+
+		led.default_state = led_init_default_state_get(fwnode);
+
+		ret = led_pwm_add(dev, priv, &led, fwnode);
+		if (ret)
+			goto err_child_out;
+	}
+
+	return 0;
+
+err_child_out:
+	fwnode_handle_put(fwnode);
+	return ret;
+}
+
+static int led_pwm_probe(struct platform_device *pdev)
+{
+	struct led_pwm_priv *priv;
+	int ret = 0;
+	int count;
+
+	count = device_get_child_node_count(&pdev->dev);
+
+	if (!count)
+		return -EINVAL;
+
+	priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, count),
+			    GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	ret = led_pwm_create_fwnode(&pdev->dev, priv);
+
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+}
+
+static const struct of_device_id of_pwm_leds_match[] = {
+	{ .compatible = "pwm-leds", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_pwm_leds_match);
+
+static struct platform_driver led_pwm_driver = {
+	.probe		= led_pwm_probe,
+	.driver		= {
+		.name	= "leds_pwm",
+		.of_match_table = of_pwm_leds_match,
+	},
+};
+
+module_platform_driver(led_pwm_driver);
+
+MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
+MODULE_DESCRIPTION("generic PWM LED driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:leds-pwm");