workqueue: skip the node_nr_active update for non-unbound workqueuesgrafted

apply_wqattrs_commit() updates node_nr_active->max unconditionally.
wq->node_nr_active[] is only allocated for unbound workqueues, so guard
the call before per-cpu workqueues start using this path.

No functional change: only unbound workqueues reach apply_wqattrs_*()
today.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 142 insertions, 0 deletions

diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
new file mode 100644
index 000000000..3b3e6869e
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ledtrig-gio.c - LED Trigger Based on GPIO events
+ *
+ * Copyright 2009 Felipe Balbi <me@felipebalbi.com>
+ * Copyright 2023 Linus Walleij <linus.walleij@linaro.org>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/leds.h>
+#include <linux/slab.h>
+#include "../leds.h"
+
+struct gpio_trig_data {
+	struct led_classdev *led;
+	unsigned desired_brightness;	/* desired brightness when led is on */
+	struct gpio_desc *gpiod;	/* gpio that triggers the led */
+};
+
+static irqreturn_t gpio_trig_irq(int irq, void *_led)
+{
+	struct led_classdev *led = _led;
+	struct gpio_trig_data *gpio_data = led_get_trigger_data(led);
+	int tmp;
+
+	tmp = gpiod_get_value_cansleep(gpio_data->gpiod);
+	if (tmp) {
+		if (gpio_data->desired_brightness)
+			led_set_brightness_nosleep(gpio_data->led,
+					   gpio_data->desired_brightness);
+		else
+			led_set_brightness_nosleep(gpio_data->led, LED_FULL);
+	} else {
+		led_set_brightness_nosleep(gpio_data->led, LED_OFF);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static ssize_t desired_brightness_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%u\n", gpio_data->desired_brightness);
+}
+
+static ssize_t desired_brightness_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t n)
+{
+	struct gpio_trig_data *gpio_data = led_trigger_get_drvdata(dev);
+	u8 desired_brightness;
+	int ret;
+
+	ret = kstrtou8(buf, 10, &desired_brightness);
+	if (ret)
+		return ret;
+
+	gpio_data->desired_brightness = desired_brightness;
+
+	return n;
+}
+static DEVICE_ATTR_RW(desired_brightness);
+
+static struct attribute *gpio_trig_attrs[] = {
+	&dev_attr_desired_brightness.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(gpio_trig);
+
+static int gpio_trig_activate(struct led_classdev *led)
+{
+	struct gpio_trig_data *gpio_data;
+	struct device *dev = led->dev;
+	int ret;
+
+	gpio_data = kzalloc_obj(*gpio_data);
+	if (!gpio_data)
+		return -ENOMEM;
+
+	/*
+	 * The generic property "trigger-sources" is followed,
+	 * and we hope that this is a GPIO.
+	 */
+	gpio_data->gpiod = gpiod_get_optional(dev, "trigger-sources",
+					      GPIOD_IN | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
+	if (IS_ERR(gpio_data->gpiod)) {
+		ret = PTR_ERR(gpio_data->gpiod);
+		kfree(gpio_data);
+		return ret;
+	}
+	if (!gpio_data->gpiod) {
+		dev_err(dev, "no valid GPIO for the trigger\n");
+		kfree(gpio_data);
+		return -EINVAL;
+	}
+
+	gpiod_set_consumer_name(gpio_data->gpiod, "led-trigger");
+
+	gpio_data->led = led;
+	led_set_trigger_data(led, gpio_data);
+
+	ret = request_threaded_irq(gpiod_to_irq(gpio_data->gpiod), NULL, gpio_trig_irq,
+			IRQF_ONESHOT | IRQF_SHARED | IRQF_TRIGGER_RISING
+			| IRQF_TRIGGER_FALLING, "ledtrig-gpio", led);
+	if (ret) {
+		dev_err(dev, "request_irq failed with error %d\n", ret);
+		gpiod_put(gpio_data->gpiod);
+		kfree(gpio_data);
+		return ret;
+	}
+
+	/* Finally update the LED to initial status */
+	gpio_trig_irq(0, led);
+
+	return 0;
+}
+
+static void gpio_trig_deactivate(struct led_classdev *led)
+{
+	struct gpio_trig_data *gpio_data = led_get_trigger_data(led);
+
+	free_irq(gpiod_to_irq(gpio_data->gpiod), led);
+	gpiod_put(gpio_data->gpiod);
+	kfree(gpio_data);
+}
+
+static struct led_trigger gpio_led_trigger = {
+	.name		= "gpio",
+	.activate	= gpio_trig_activate,
+	.deactivate	= gpio_trig_deactivate,
+	.groups		= gpio_trig_groups,
+};
+module_led_trigger(gpio_led_trigger);
+
+MODULE_AUTHOR("Felipe Balbi <me@felipebalbi.com>");
+MODULE_DESCRIPTION("GPIO LED trigger");
+MODULE_LICENSE("GPL v2");