Adding upstream version 6.1.76.upstream/6.1.76

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

1 files changed, 464 insertions, 0 deletions

diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
new file mode 100644
index 000000000..072491d3e
--- /dev/null
+++ b/drivers/leds/led-triggers.c
@@ -0,0 +1,464 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * LED Triggers Core
+ *
+ * Copyright 2005-2007 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <rpurdie@openedhand.com>
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/timer.h>
+#include <linux/rwsem.h>
+#include <linux/leds.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include "leds.h"
+
+/*
+ * Nests outside led_cdev->trigger_lock
+ */
+static DECLARE_RWSEM(triggers_list_lock);
+LIST_HEAD(trigger_list);
+
+ /* Used by LED Class */
+
+static inline bool
+trigger_relevant(struct led_classdev *led_cdev, struct led_trigger *trig)
+{
+	return !trig->trigger_type || trig->trigger_type == led_cdev->trigger_type;
+}
+
+ssize_t led_trigger_write(struct file *filp, struct kobject *kobj,
+			  struct bin_attribute *bin_attr, char *buf,
+			  loff_t pos, size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct led_trigger *trig;
+	int ret = count;
+
+	mutex_lock(&led_cdev->led_access);
+
+	if (led_sysfs_is_disabled(led_cdev)) {
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	if (sysfs_streq(buf, "none")) {
+		led_trigger_remove(led_cdev);
+		goto unlock;
+	}
+
+	down_read(&triggers_list_lock);
+	list_for_each_entry(trig, &trigger_list, next_trig) {
+		if (sysfs_streq(buf, trig->name) && trigger_relevant(led_cdev, trig)) {
+			down_write(&led_cdev->trigger_lock);
+			led_trigger_set(led_cdev, trig);
+			up_write(&led_cdev->trigger_lock);
+
+			up_read(&triggers_list_lock);
+			goto unlock;
+		}
+	}
+	/* we come here only if buf matches no trigger */
+	ret = -EINVAL;
+	up_read(&triggers_list_lock);
+
+unlock:
+	mutex_unlock(&led_cdev->led_access);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(led_trigger_write);
+
+__printf(3, 4)
+static int led_trigger_snprintf(char *buf, ssize_t size, const char *fmt, ...)
+{
+	va_list args;
+	int i;
+
+	va_start(args, fmt);
+	if (size <= 0)
+		i = vsnprintf(NULL, 0, fmt, args);
+	else
+		i = vscnprintf(buf, size, fmt, args);
+	va_end(args);
+
+	return i;
+}
+
+static int led_trigger_format(char *buf, size_t size,
+			      struct led_classdev *led_cdev)
+{
+	struct led_trigger *trig;
+	int len = led_trigger_snprintf(buf, size, "%s",
+				       led_cdev->trigger ? "none" : "[none]");
+
+	list_for_each_entry(trig, &trigger_list, next_trig) {
+		bool hit;
+
+		if (!trigger_relevant(led_cdev, trig))
+			continue;
+
+		hit = led_cdev->trigger && !strcmp(led_cdev->trigger->name, trig->name);
+
+		len += led_trigger_snprintf(buf + len, size - len,
+					    " %s%s%s", hit ? "[" : "",
+					    trig->name, hit ? "]" : "");
+	}
+
+	len += led_trigger_snprintf(buf + len, size - len, "\n");
+
+	return len;
+}
+
+/*
+ * It was stupid to create 10000 cpu triggers, but we are stuck with it now.
+ * Don't make that mistake again. We work around it here by creating binary
+ * attribute, which is not limited by length. This is _not_ good design, do not
+ * copy it.
+ */
+ssize_t led_trigger_read(struct file *filp, struct kobject *kobj,
+			struct bin_attribute *attr, char *buf,
+			loff_t pos, size_t count)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	void *data;
+	int len;
+
+	down_read(&triggers_list_lock);
+	down_read(&led_cdev->trigger_lock);
+
+	len = led_trigger_format(NULL, 0, led_cdev);
+	data = kvmalloc(len + 1, GFP_KERNEL);
+	if (!data) {
+		up_read(&led_cdev->trigger_lock);
+		up_read(&triggers_list_lock);
+		return -ENOMEM;
+	}
+	len = led_trigger_format(data, len + 1, led_cdev);
+
+	up_read(&led_cdev->trigger_lock);
+	up_read(&triggers_list_lock);
+
+	len = memory_read_from_buffer(buf, count, &pos, data, len);
+
+	kvfree(data);
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(led_trigger_read);
+
+/* Caller must ensure led_cdev->trigger_lock held */
+int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
+{
+	char *event = NULL;
+	char *envp[2];
+	const char *name;
+	int ret;
+
+	if (!led_cdev->trigger && !trig)
+		return 0;
+
+	name = trig ? trig->name : "none";
+	event = kasprintf(GFP_KERNEL, "TRIGGER=%s", name);
+
+	/* Remove any existing trigger */
+	if (led_cdev->trigger) {
+		spin_lock(&led_cdev->trigger->leddev_list_lock);
+		list_del_rcu(&led_cdev->trig_list);
+		spin_unlock(&led_cdev->trigger->leddev_list_lock);
+
+		/* ensure it's no longer visible on the led_cdevs list */
+		synchronize_rcu();
+
+		cancel_work_sync(&led_cdev->set_brightness_work);
+		led_stop_software_blink(led_cdev);
+		if (led_cdev->trigger->deactivate)
+			led_cdev->trigger->deactivate(led_cdev);
+		device_remove_groups(led_cdev->dev, led_cdev->trigger->groups);
+		led_cdev->trigger = NULL;
+		led_cdev->trigger_data = NULL;
+		led_cdev->activated = false;
+		led_set_brightness(led_cdev, LED_OFF);
+	}
+	if (trig) {
+		spin_lock(&trig->leddev_list_lock);
+		list_add_tail_rcu(&led_cdev->trig_list, &trig->led_cdevs);
+		spin_unlock(&trig->leddev_list_lock);
+		led_cdev->trigger = trig;
+
+		if (trig->activate)
+			ret = trig->activate(led_cdev);
+		else
+			ret = 0;
+
+		if (ret)
+			goto err_activate;
+
+		ret = device_add_groups(led_cdev->dev, trig->groups);
+		if (ret) {
+			dev_err(led_cdev->dev, "Failed to add trigger attributes\n");
+			goto err_add_groups;
+		}
+	}
+
+	if (event) {
+		envp[0] = event;
+		envp[1] = NULL;
+		if (kobject_uevent_env(&led_cdev->dev->kobj, KOBJ_CHANGE, envp))
+			dev_err(led_cdev->dev,
+				"%s: Error sending uevent\n", __func__);
+		kfree(event);
+	}
+
+	return 0;
+
+err_add_groups:
+
+	if (trig->deactivate)
+		trig->deactivate(led_cdev);
+err_activate:
+
+	spin_lock(&led_cdev->trigger->leddev_list_lock);
+	list_del_rcu(&led_cdev->trig_list);
+	spin_unlock(&led_cdev->trigger->leddev_list_lock);
+	synchronize_rcu();
+	led_cdev->trigger = NULL;
+	led_cdev->trigger_data = NULL;
+	led_set_brightness(led_cdev, LED_OFF);
+	kfree(event);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(led_trigger_set);
+
+void led_trigger_remove(struct led_classdev *led_cdev)
+{
+	down_write(&led_cdev->trigger_lock);
+	led_trigger_set(led_cdev, NULL);
+	up_write(&led_cdev->trigger_lock);
+}
+EXPORT_SYMBOL_GPL(led_trigger_remove);
+
+void led_trigger_set_default(struct led_classdev *led_cdev)
+{
+	struct led_trigger *trig;
+
+	if (!led_cdev->default_trigger)
+		return;
+
+	down_read(&triggers_list_lock);
+	down_write(&led_cdev->trigger_lock);
+	list_for_each_entry(trig, &trigger_list, next_trig) {
+		if (!strcmp(led_cdev->default_trigger, trig->name) &&
+		    trigger_relevant(led_cdev, trig)) {
+			led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
+			led_trigger_set(led_cdev, trig);
+			break;
+		}
+	}
+	up_write(&led_cdev->trigger_lock);
+	up_read(&triggers_list_lock);
+}
+EXPORT_SYMBOL_GPL(led_trigger_set_default);
+
+void led_trigger_rename_static(const char *name, struct led_trigger *trig)
+{
+	/* new name must be on a temporary string to prevent races */
+	BUG_ON(name == trig->name);
+
+	down_write(&triggers_list_lock);
+	/* this assumes that trig->name was originaly allocated to
+	 * non constant storage */
+	strcpy((char *)trig->name, name);
+	up_write(&triggers_list_lock);
+}
+EXPORT_SYMBOL_GPL(led_trigger_rename_static);
+
+/* LED Trigger Interface */
+
+int led_trigger_register(struct led_trigger *trig)
+{
+	struct led_classdev *led_cdev;
+	struct led_trigger *_trig;
+
+	spin_lock_init(&trig->leddev_list_lock);
+	INIT_LIST_HEAD(&trig->led_cdevs);
+
+	down_write(&triggers_list_lock);
+	/* Make sure the trigger's name isn't already in use */
+	list_for_each_entry(_trig, &trigger_list, next_trig) {
+		if (!strcmp(_trig->name, trig->name) &&
+		    (trig->trigger_type == _trig->trigger_type ||
+		     !trig->trigger_type || !_trig->trigger_type)) {
+			up_write(&triggers_list_lock);
+			return -EEXIST;
+		}
+	}
+	/* Add to the list of led triggers */
+	list_add_tail(&trig->next_trig, &trigger_list);
+	up_write(&triggers_list_lock);
+
+	/* Register with any LEDs that have this as a default trigger */
+	down_read(&leds_list_lock);
+	list_for_each_entry(led_cdev, &leds_list, node) {
+		down_write(&led_cdev->trigger_lock);
+		if (!led_cdev->trigger && led_cdev->default_trigger &&
+		    !strcmp(led_cdev->default_trigger, trig->name) &&
+		    trigger_relevant(led_cdev, trig)) {
+			led_cdev->flags |= LED_INIT_DEFAULT_TRIGGER;
+			led_trigger_set(led_cdev, trig);
+		}
+		up_write(&led_cdev->trigger_lock);
+	}
+	up_read(&leds_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(led_trigger_register);
+
+void led_trigger_unregister(struct led_trigger *trig)
+{
+	struct led_classdev *led_cdev;
+
+	if (list_empty_careful(&trig->next_trig))
+		return;
+
+	/* Remove from the list of led triggers */
+	down_write(&triggers_list_lock);
+	list_del_init(&trig->next_trig);
+	up_write(&triggers_list_lock);
+
+	/* Remove anyone actively using this trigger */
+	down_read(&leds_list_lock);
+	list_for_each_entry(led_cdev, &leds_list, node) {
+		down_write(&led_cdev->trigger_lock);
+		if (led_cdev->trigger == trig)
+			led_trigger_set(led_cdev, NULL);
+		up_write(&led_cdev->trigger_lock);
+	}
+	up_read(&leds_list_lock);
+}
+EXPORT_SYMBOL_GPL(led_trigger_unregister);
+
+static void devm_led_trigger_release(struct device *dev, void *res)
+{
+	led_trigger_unregister(*(struct led_trigger **)res);
+}
+
+int devm_led_trigger_register(struct device *dev,
+			      struct led_trigger *trig)
+{
+	struct led_trigger **dr;
+	int rc;
+
+	dr = devres_alloc(devm_led_trigger_release, sizeof(*dr),
+			  GFP_KERNEL);
+	if (!dr)
+		return -ENOMEM;
+
+	*dr = trig;
+
+	rc = led_trigger_register(trig);
+	if (rc)
+		devres_free(dr);
+	else
+		devres_add(dev, dr);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(devm_led_trigger_register);
+
+/* Simple LED Trigger Interface */
+
+void led_trigger_event(struct led_trigger *trig,
+			enum led_brightness brightness)
+{
+	struct led_classdev *led_cdev;
+
+	if (!trig)
+		return;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list)
+		led_set_brightness(led_cdev, brightness);
+	rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(led_trigger_event);
+
+static void led_trigger_blink_setup(struct led_trigger *trig,
+			     unsigned long *delay_on,
+			     unsigned long *delay_off,
+			     int oneshot,
+			     int invert)
+{
+	struct led_classdev *led_cdev;
+
+	if (!trig)
+		return;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(led_cdev, &trig->led_cdevs, trig_list) {
+		if (oneshot)
+			led_blink_set_oneshot(led_cdev, delay_on, delay_off,
+					      invert);
+		else
+			led_blink_set(led_cdev, delay_on, delay_off);
+	}
+	rcu_read_unlock();
+}
+
+void led_trigger_blink(struct led_trigger *trig,
+		       unsigned long *delay_on,
+		       unsigned long *delay_off)
+{
+	led_trigger_blink_setup(trig, delay_on, delay_off, 0, 0);
+}
+EXPORT_SYMBOL_GPL(led_trigger_blink);
+
+void led_trigger_blink_oneshot(struct led_trigger *trig,
+			       unsigned long *delay_on,
+			       unsigned long *delay_off,
+			       int invert)
+{
+	led_trigger_blink_setup(trig, delay_on, delay_off, 1, invert);
+}
+EXPORT_SYMBOL_GPL(led_trigger_blink_oneshot);
+
+void led_trigger_register_simple(const char *name, struct led_trigger **tp)
+{
+	struct led_trigger *trig;
+	int err;
+
+	trig = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
+
+	if (trig) {
+		trig->name = name;
+		err = led_trigger_register(trig);
+		if (err < 0) {
+			kfree(trig);
+			trig = NULL;
+			pr_warn("LED trigger %s failed to register (%d)\n",
+				name, err);
+		}
+	} else {
+		pr_warn("LED trigger %s failed to register (no memory)\n",
+			name);
+	}
+	*tp = trig;
+}
+EXPORT_SYMBOL_GPL(led_trigger_register_simple);
+
+void led_trigger_unregister_simple(struct led_trigger *trig)
+{
+	if (trig)
+		led_trigger_unregister(trig);
+	kfree(trig);
+}
+EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);