linux_dsm_epyc7002/drivers/leds/trigger/ledtrig-oneshot.c
Krzysztof Kozlowski 9c9ab51e86 leds: trigger: oneshot: Add initialization from Device Tree
Allow initialization of delays used in oneshot trigger from Device
Tree property.

This is especially useful for embedded systems where the trigger might
be used early, before bringing up user-space.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-01-16 22:09:18 +01:00

204 lines
4.9 KiB
C

/*
* One-shot LED Trigger
*
* Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com>
*
* Based on ledtrig-timer.c by Richard Purdie <rpurdie@openedhand.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#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>
#include "../leds.h"
#define DEFAULT_DELAY 100
struct oneshot_trig_data {
unsigned int invert;
};
static ssize_t led_shot(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = led_trigger_get_led(dev);
struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
led_blink_set_oneshot(led_cdev,
&led_cdev->blink_delay_on, &led_cdev->blink_delay_off,
oneshot_data->invert);
/* content is ignored */
return size;
}
static ssize_t led_invert_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
return sprintf(buf, "%u\n", oneshot_data->invert);
}
static ssize_t led_invert_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = led_trigger_get_led(dev);
struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev);
unsigned long state;
int ret;
ret = kstrtoul(buf, 0, &state);
if (ret)
return ret;
oneshot_data->invert = !!state;
if (oneshot_data->invert)
led_set_brightness_nosleep(led_cdev, LED_FULL);
else
led_set_brightness_nosleep(led_cdev, LED_OFF);
return size;
}
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;
int ret;
ret = kstrtoul(buf, 0, &state);
if (ret)
return ret;
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;
int ret;
ret = kstrtoul(buf, 0, &state);
if (ret)
return ret;
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 DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store);
static DEVICE_ATTR(shot, 0200, NULL, led_shot);
static struct attribute *oneshot_trig_attrs[] = {
&dev_attr_delay_on.attr,
&dev_attr_delay_off.attr,
&dev_attr_invert.attr,
&dev_attr_shot.attr,
NULL
};
ATTRIBUTE_GROUPS(oneshot_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)
goto out_default;
if (size != 2) {
dev_warn(led_cdev->dev,
"Expected 2 but got %u values for delays pattern\n",
size);
goto out_default;
}
led_cdev->blink_delay_on = pattern[0];
led_cdev->blink_delay_off = pattern[1];
kfree(pattern);
return;
out_default:
kfree(pattern);
led_cdev->blink_delay_on = DEFAULT_DELAY;
led_cdev->blink_delay_off = DEFAULT_DELAY;
}
static int oneshot_trig_activate(struct led_classdev *led_cdev)
{
struct oneshot_trig_data *oneshot_data;
oneshot_data = kzalloc(sizeof(*oneshot_data), GFP_KERNEL);
if (!oneshot_data)
return -ENOMEM;
led_set_trigger_data(led_cdev, oneshot_data);
if (led_cdev->flags & LED_INIT_DEFAULT_TRIGGER) {
pattern_init(led_cdev);
/*
* Mark as initialized even on pattern_init() error because
* any consecutive call to it would produce the same error.
*/
led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER;
}
return 0;
}
static void oneshot_trig_deactivate(struct led_classdev *led_cdev)
{
struct oneshot_trig_data *oneshot_data = led_get_trigger_data(led_cdev);
kfree(oneshot_data);
/* Stop blinking */
led_set_brightness(led_cdev, LED_OFF);
}
static struct led_trigger oneshot_led_trigger = {
.name = "oneshot",
.activate = oneshot_trig_activate,
.deactivate = oneshot_trig_deactivate,
.groups = oneshot_trig_groups,
};
module_led_trigger(oneshot_led_trigger);
MODULE_AUTHOR("Fabio Baltieri <fabio.baltieri@gmail.com>");
MODULE_DESCRIPTION("One-shot LED trigger");
MODULE_LICENSE("GPL v2");