drivers/leds/trigger/ledtrig-timer.c
Source file repositories/reference/linux-study-clean/drivers/leds/trigger/ledtrig-timer.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/leds/trigger/ledtrig-timer.c- Extension
.c- Size
- 3218 bytes
- Lines
- 136
- Domain
- Driver Families
- Bucket
- drivers/leds
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/module.hlinux/kernel.hlinux/init.hlinux/device.hlinux/ctype.hlinux/slab.hlinux/leds.h
Detected Declarations
function led_delay_on_showfunction led_delay_on_storefunction led_delay_off_showfunction led_delay_off_storefunction pattern_initfunction timer_trig_activatefunction timer_trig_deactivate
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0-only
/*
* LED Kernel Timer Trigger
*
* Copyright 2005-2006 Openedhand Ltd.
*
* Author: Richard Purdie <rpurdie@openedhand.com>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/ctype.h>
#include <linux/slab.h>
#include <linux/leds.h>
static ssize_t led_delay_on_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = led_trigger_get_led(dev);
return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
}
static ssize_t led_delay_on_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = led_trigger_get_led(dev);
unsigned long state;
ssize_t ret;
ret = kstrtoul(buf, 10, &state);
if (ret)
return ret;
led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
led_cdev->blink_delay_on = state;
return size;
}
static ssize_t led_delay_off_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = led_trigger_get_led(dev);
return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
}
static ssize_t led_delay_off_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = led_trigger_get_led(dev);
unsigned long state;
ssize_t ret;
ret = kstrtoul(buf, 10, &state);
if (ret)
return ret;
led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
led_cdev->blink_delay_off = state;
return size;
}
static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
static struct attribute *timer_trig_attrs[] = {
&dev_attr_delay_on.attr,
&dev_attr_delay_off.attr,
NULL
};
ATTRIBUTE_GROUPS(timer_trig);
static void pattern_init(struct led_classdev *led_cdev)
{
u32 *pattern;
unsigned int size = 0;
pattern = led_get_default_pattern(led_cdev, &size);
if (!pattern)
return;
if (size != 2) {
dev_warn(led_cdev->dev,
"Expected 2 but got %u values for delays pattern\n",
size);
Annotation
- Immediate include surface: `linux/module.h`, `linux/kernel.h`, `linux/init.h`, `linux/device.h`, `linux/ctype.h`, `linux/slab.h`, `linux/leds.h`.
- Detected declarations: `function led_delay_on_show`, `function led_delay_on_store`, `function led_delay_off_show`, `function led_delay_off_store`, `function pattern_init`, `function timer_trig_activate`, `function timer_trig_deactivate`.
- Atlas domain: Driver Families / drivers/leds.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.