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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /drivers/leds/uleds.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'drivers/leds/uleds.c')
-rw-r--r--drivers/leds/uleds.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/drivers/leds/uleds.c b/drivers/leds/uleds.c
new file mode 100644
index 000000000..6affa581b
--- /dev/null
+++ b/drivers/leds/uleds.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Userspace driver for the LED subsystem
+ *
+ * Copyright (C) 2016 David Lechner <david@lechnology.com>
+ *
+ * Based on uinput.c: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
+ */
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include <uapi/linux/uleds.h>
+
+#define ULEDS_NAME "uleds"
+
+enum uleds_state {
+ ULEDS_STATE_UNKNOWN,
+ ULEDS_STATE_REGISTERED,
+};
+
+struct uleds_device {
+ struct uleds_user_dev user_dev;
+ struct led_classdev led_cdev;
+ struct mutex mutex;
+ enum uleds_state state;
+ wait_queue_head_t waitq;
+ int brightness;
+ bool new_data;
+};
+
+static struct miscdevice uleds_misc;
+
+static void uleds_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ struct uleds_device *udev = container_of(led_cdev, struct uleds_device,
+ led_cdev);
+
+ if (udev->brightness != brightness) {
+ udev->brightness = brightness;
+ udev->new_data = true;
+ wake_up_interruptible(&udev->waitq);
+ }
+}
+
+static int uleds_open(struct inode *inode, struct file *file)
+{
+ struct uleds_device *udev;
+
+ udev = kzalloc_obj(*udev);
+ if (!udev)
+ return -ENOMEM;
+
+ udev->led_cdev.name = udev->user_dev.name;
+ udev->led_cdev.brightness_set = uleds_brightness_set;
+
+ mutex_init(&udev->mutex);
+ init_waitqueue_head(&udev->waitq);
+ udev->state = ULEDS_STATE_UNKNOWN;
+
+ file->private_data = udev;
+ stream_open(inode, file);
+
+ return 0;
+}
+
+static ssize_t uleds_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct uleds_device *udev = file->private_data;
+ const char *name;
+ int ret;
+
+ if (count == 0)
+ return 0;
+
+ ret = mutex_lock_interruptible(&udev->mutex);
+ if (ret)
+ return ret;
+
+ if (udev->state == ULEDS_STATE_REGISTERED) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ if (count != sizeof(struct uleds_user_dev)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (copy_from_user(&udev->user_dev, buffer,
+ sizeof(struct uleds_user_dev))) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ name = udev->user_dev.name;
+ if (!name[0] || !strcmp(name, ".") || !strcmp(name, "..") ||
+ strnchr(name, sizeof(udev->user_dev.name), '/') ||
+ !strnchr(name, sizeof(udev->user_dev.name), '\0')) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (udev->user_dev.max_brightness <= 0) {
+ ret = -EINVAL;
+ goto out;
+ }
+ udev->led_cdev.max_brightness = udev->user_dev.max_brightness;
+
+ ret = devm_led_classdev_register(uleds_misc.this_device,
+ &udev->led_cdev);
+ if (ret < 0)
+ goto out;
+
+ udev->new_data = true;
+ udev->state = ULEDS_STATE_REGISTERED;
+ ret = count;
+
+out:
+ mutex_unlock(&udev->mutex);
+
+ return ret;
+}
+
+static ssize_t uleds_read(struct file *file, char __user *buffer, size_t count,
+ loff_t *ppos)
+{
+ struct uleds_device *udev = file->private_data;
+ ssize_t retval;
+
+ if (count < sizeof(udev->brightness))
+ return 0;
+
+ do {
+ retval = mutex_lock_interruptible(&udev->mutex);
+ if (retval)
+ return retval;
+
+ if (udev->state != ULEDS_STATE_REGISTERED) {
+ retval = -ENODEV;
+ } else if (!udev->new_data && (file->f_flags & O_NONBLOCK)) {
+ retval = -EAGAIN;
+ } else if (udev->new_data) {
+ if (copy_to_user(buffer, &udev->brightness,
+ sizeof(udev->brightness))) {
+ retval = -EFAULT;
+ } else {
+ udev->new_data = false;
+ retval = sizeof(udev->brightness);
+ }
+ }
+
+ mutex_unlock(&udev->mutex);
+
+ if (retval)
+ break;
+
+ if (!(file->f_flags & O_NONBLOCK))
+ retval = wait_event_interruptible(udev->waitq,
+ udev->new_data ||
+ udev->state != ULEDS_STATE_REGISTERED);
+ } while (retval == 0);
+
+ return retval;
+}
+
+static __poll_t uleds_poll(struct file *file, poll_table *wait)
+{
+ struct uleds_device *udev = file->private_data;
+
+ poll_wait(file, &udev->waitq, wait);
+
+ if (udev->new_data)
+ return EPOLLIN | EPOLLRDNORM;
+
+ return 0;
+}
+
+static int uleds_release(struct inode *inode, struct file *file)
+{
+ struct uleds_device *udev = file->private_data;
+
+ if (udev->state == ULEDS_STATE_REGISTERED) {
+ udev->state = ULEDS_STATE_UNKNOWN;
+ devm_led_classdev_unregister(uleds_misc.this_device,
+ &udev->led_cdev);
+ }
+ kfree(udev);
+
+ return 0;
+}
+
+static const struct file_operations uleds_fops = {
+ .owner = THIS_MODULE,
+ .open = uleds_open,
+ .release = uleds_release,
+ .read = uleds_read,
+ .write = uleds_write,
+ .poll = uleds_poll,
+};
+
+static struct miscdevice uleds_misc = {
+ .fops = &uleds_fops,
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = ULEDS_NAME,
+};
+
+module_misc_device(uleds_misc);
+
+MODULE_AUTHOR("David Lechner <david@lechnology.com>");
+MODULE_DESCRIPTION("Userspace driver for the LED subsystem");
+MODULE_LICENSE("GPL");