1 files changed, 313 insertions, 0 deletions
diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c
new file mode 100644
index 000000000..092eb59a7
--- /dev/null
+++ b/drivers/leds/leds-gpio.c
@@ -0,0 +1,313 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * LEDs driver for GPIOs
+ *
+ * Copyright (C) 2007 8D Technologies inc.
+ * Raphael Assenat <raph@8d.com>
+ * Copyright (C) 2008 Freescale Semiconductor, Inc.
+ */
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include "leds.h"
+
+struct gpio_led_data {
+	struct led_classdev cdev;
+	struct gpio_desc *gpiod;
+	u8 can_sleep;
+	u8 blinking;
+	gpio_blink_set_t platform_gpio_blink_set;
+};
+
+static inline struct gpio_led_data *
+			cdev_to_gpio_led_data(struct led_classdev *led_cdev)
+{
+	return container_of(led_cdev, struct gpio_led_data, cdev);
+}
+
+static void gpio_led_set(struct led_classdev *led_cdev,
+	enum led_brightness value)
+{
+	struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
+	int level;
+
+	if (value == LED_OFF)
+		level = 0;
+	else
+		level = 1;
+
+	if (led_dat->blinking) {
+		led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
+						 NULL, NULL);
+		led_dat->blinking = 0;
+	} else {
+		if (led_dat->can_sleep)
+			gpiod_set_value_cansleep(led_dat->gpiod, level);
+		else
+			gpiod_set_value(led_dat->gpiod, level);
+	}
+}
+
+static int gpio_led_set_blocking(struct led_classdev *led_cdev,
+	enum led_brightness value)
+{
+	gpio_led_set(led_cdev, value);
+	return 0;
+}
+
+static int gpio_blink_set(struct led_classdev *led_cdev,
+	unsigned long *delay_on, unsigned long *delay_off)
+{
+	struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
+
+	led_dat->blinking = 1;
+	return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
+						delay_on, delay_off);
+}
+
+static int create_gpio_led(const struct gpio_led *template,
+	struct gpio_led_data *led_dat, struct device *parent,
+	struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
+{
+	struct led_init_data init_data = {};
+	int ret, state;
+
+	led_dat->cdev.default_trigger = template->default_trigger;
+	led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
+	if (!led_dat->can_sleep)
+		led_dat->cdev.brightness_set = gpio_led_set;
+	else
+		led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
+	led_dat->blinking = 0;
+	if (blink_set) {
+		led_dat->platform_gpio_blink_set = blink_set;
+		led_dat->cdev.blink_set = gpio_blink_set;
+	}
+	if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
+		state = gpiod_get_value_cansleep(led_dat->gpiod);
+		if (state < 0)
+			return state;
+	} else {
+		state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
+	}
+	led_dat->cdev.brightness = state;
+	led_dat->cdev.max_brightness = 1;
+	if (!template->retain_state_suspended)
+		led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
+	if (template->panic_indicator)
+		led_dat->cdev.flags |= LED_PANIC_INDICATOR;
+	if (template->retain_state_shutdown)
+		led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
+
+	ret = gpiod_direction_output(led_dat->gpiod, state);
+	if (ret < 0)
+		return ret;
+
+	if (template->name) {
+		led_dat->cdev.name = template->name;
+		ret = devm_led_classdev_register(parent, &led_dat->cdev);
+	} else {
+		init_data.fwnode = fwnode;
+		ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
+						     &init_data);
+	}
+
+	return ret;
+}
+
+struct gpio_leds_priv {
+	int num_leds;
+	struct gpio_led_data leds[];
+};
+
+static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct fwnode_handle *child;
+	struct gpio_leds_priv *priv;
+	int count, ret;
+
+	count = device_get_child_node_count(dev);
+	if (!count)
+		return ERR_PTR(-ENODEV);
+
+	priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
+	if (!priv)
+		return ERR_PTR(-ENOMEM);
+
+	device_for_each_child_node(dev, child) {
+		struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
+		struct gpio_led led = {};
+
+		/*
+		 * Acquire gpiod from DT with uninitialized label, which
+		 * will be updated after LED class device is registered,
+		 * Only then the final LED name is known.
+		 */
+		led.gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, child,
+							     GPIOD_ASIS,
+							     NULL);
+		if (IS_ERR(led.gpiod)) {
+			fwnode_handle_put(child);
+			return ERR_CAST(led.gpiod);
+		}
+
+		led_dat->gpiod = led.gpiod;
+
+		led.default_state = led_init_default_state_get(child);
+
+		if (fwnode_property_present(child, "retain-state-suspended"))
+			led.retain_state_suspended = 1;
+		if (fwnode_property_present(child, "retain-state-shutdown"))
+			led.retain_state_shutdown = 1;
+		if (fwnode_property_present(child, "panic-indicator"))
+			led.panic_indicator = 1;
+
+		ret = create_gpio_led(&led, led_dat, dev, child, NULL);
+		if (ret < 0) {
+			fwnode_handle_put(child);
+			return ERR_PTR(ret);
+		}
+		/* Set gpiod label to match the corresponding LED name. */
+		gpiod_set_consumer_name(led_dat->gpiod,
+					led_dat->cdev.dev->kobj.name);
+		priv->num_leds++;
+	}
+
+	return priv;
+}
+
+static const struct of_device_id of_gpio_leds_match[] = {
+	{ .compatible = "gpio-leds", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
+
+static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
+					    const struct gpio_led *template)
+{
+	struct gpio_desc *gpiod;
+	unsigned long flags = GPIOF_OUT_INIT_LOW;
+	int ret;
+
+	/*
+	 * This means the LED does not come from the device tree
+	 * or ACPI, so let's try just getting it by index from the
+	 * device, this will hit the board file, if any and get
+	 * the GPIO from there.
+	 */
+	gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
+	if (!IS_ERR(gpiod)) {
+		gpiod_set_consumer_name(gpiod, template->name);
+		return gpiod;
+	}
+	if (PTR_ERR(gpiod) != -ENOENT)
+		return gpiod;
+
+	/*
+	 * This is the legacy code path for platform code that
+	 * still uses GPIO numbers. Ultimately we would like to get
+	 * rid of this block completely.
+	 */
+
+	/* skip leds that aren't available */
+	if (!gpio_is_valid(template->gpio))
+		return ERR_PTR(-ENOENT);
+
+	if (template->active_low)
+		flags |= GPIOF_ACTIVE_LOW;
+
+	ret = devm_gpio_request_one(dev, template->gpio, flags,
+				    template->name);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	gpiod = gpio_to_desc(template->gpio);
+	if (!gpiod)
+		return ERR_PTR(-EINVAL);
+
+	return gpiod;
+}
+
+static int gpio_led_probe(struct platform_device *pdev)
+{
+	struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct gpio_leds_priv *priv;
+	int i, ret = 0;
+
+	if (pdata && pdata->num_leds) {
+		priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
+				    GFP_KERNEL);
+		if (!priv)
+			return -ENOMEM;
+
+		priv->num_leds = pdata->num_leds;
+		for (i = 0; i < priv->num_leds; i++) {
+			const struct gpio_led *template = &pdata->leds[i];
+			struct gpio_led_data *led_dat = &priv->leds[i];
+
+			if (template->gpiod)
+				led_dat->gpiod = template->gpiod;
+			else
+				led_dat->gpiod =
+					gpio_led_get_gpiod(&pdev->dev,
+							   i, template);
+			if (IS_ERR(led_dat->gpiod)) {
+				dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
+					 template->gpio, template->name);
+				continue;
+			}
+
+			ret = create_gpio_led(template, led_dat,
+					      &pdev->dev, NULL,
+					      pdata->gpio_blink_set);
+			if (ret < 0)
+				return ret;
+		}
+	} else {
+		priv = gpio_leds_create(pdev);
+		if (IS_ERR(priv))
+			return PTR_ERR(priv);
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+}
+
+static void gpio_led_shutdown(struct platform_device *pdev)
+{
+	struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < priv->num_leds; i++) {
+		struct gpio_led_data *led = &priv->leds[i];
+
+		if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
+			gpio_led_set(&led->cdev, LED_OFF);
+	}
+}
+
+static struct platform_driver gpio_led_driver = {
+	.probe		= gpio_led_probe,
+	.shutdown	= gpio_led_shutdown,
+	.driver		= {
+		.name	= "leds-gpio",
+		.of_match_table = of_gpio_leds_match,
+	},
+};
+
+module_platform_driver(gpio_led_driver);
+
+MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
+MODULE_DESCRIPTION("GPIO LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:leds-gpio");