linux/drivers/leds/led-core.c
Andy Shevchenko fd81d7e946 leds: Switch to use fwnode instead of be stuck with OF one
There is no need to be stuck with OF node when we may use agnostic
firmware node instead.

It allows users to get property if needed independently of provider.

Note, some OF parts are left because %pfw [1] is in progress.

[1]: https://lore.kernel.org/patchwork/cover/1054863/

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-08-23 23:39:37 +02:00

480 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* LED Class Core
*
* Copyright 2005-2006 Openedhand Ltd.
*
* Author: Richard Purdie <rpurdie@openedhand.com>
*/
#include <linux/kernel.h>
#include <linux/leds.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/property.h>
#include <linux/rwsem.h>
#include <linux/slab.h>
#include <uapi/linux/uleds.h>
#include "leds.h"
DECLARE_RWSEM(leds_list_lock);
EXPORT_SYMBOL_GPL(leds_list_lock);
LIST_HEAD(leds_list);
EXPORT_SYMBOL_GPL(leds_list);
const char * const led_colors[LED_COLOR_ID_MAX] = {
[LED_COLOR_ID_WHITE] = "white",
[LED_COLOR_ID_RED] = "red",
[LED_COLOR_ID_GREEN] = "green",
[LED_COLOR_ID_BLUE] = "blue",
[LED_COLOR_ID_AMBER] = "amber",
[LED_COLOR_ID_VIOLET] = "violet",
[LED_COLOR_ID_YELLOW] = "yellow",
[LED_COLOR_ID_IR] = "ir",
};
EXPORT_SYMBOL_GPL(led_colors);
static int __led_set_brightness(struct led_classdev *led_cdev,
enum led_brightness value)
{
if (!led_cdev->brightness_set)
return -ENOTSUPP;
led_cdev->brightness_set(led_cdev, value);
return 0;
}
static int __led_set_brightness_blocking(struct led_classdev *led_cdev,
enum led_brightness value)
{
if (!led_cdev->brightness_set_blocking)
return -ENOTSUPP;
return led_cdev->brightness_set_blocking(led_cdev, value);
}
static void led_timer_function(struct timer_list *t)
{
struct led_classdev *led_cdev = from_timer(led_cdev, t, blink_timer);
unsigned long brightness;
unsigned long delay;
if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
led_set_brightness_nosleep(led_cdev, LED_OFF);
clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
return;
}
if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP,
&led_cdev->work_flags)) {
clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
return;
}
brightness = led_get_brightness(led_cdev);
if (!brightness) {
/* Time to switch the LED on. */
if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE,
&led_cdev->work_flags))
brightness = led_cdev->new_blink_brightness;
else
brightness = led_cdev->blink_brightness;
delay = led_cdev->blink_delay_on;
} else {
/* Store the current brightness value to be able
* to restore it when the delay_off period is over.
*/
led_cdev->blink_brightness = brightness;
brightness = LED_OFF;
delay = led_cdev->blink_delay_off;
}
led_set_brightness_nosleep(led_cdev, brightness);
/* Return in next iteration if led is in one-shot mode and we are in
* the final blink state so that the led is toggled each delay_on +
* delay_off milliseconds in worst case.
*/
if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags)) {
if (test_bit(LED_BLINK_INVERT, &led_cdev->work_flags)) {
if (brightness)
set_bit(LED_BLINK_ONESHOT_STOP,
&led_cdev->work_flags);
} else {
if (!brightness)
set_bit(LED_BLINK_ONESHOT_STOP,
&led_cdev->work_flags);
}
}
mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
}
static void set_brightness_delayed(struct work_struct *ws)
{
struct led_classdev *led_cdev =
container_of(ws, struct led_classdev, set_brightness_work);
int ret = 0;
if (test_and_clear_bit(LED_BLINK_DISABLE, &led_cdev->work_flags)) {
led_cdev->delayed_set_value = LED_OFF;
led_stop_software_blink(led_cdev);
}
ret = __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
if (ret == -ENOTSUPP)
ret = __led_set_brightness_blocking(led_cdev,
led_cdev->delayed_set_value);
if (ret < 0 &&
/* LED HW might have been unplugged, therefore don't warn */
!(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&
(led_cdev->flags & LED_HW_PLUGGABLE)))
dev_err(led_cdev->dev,
"Setting an LED's brightness failed (%d)\n", ret);
}
static void led_set_software_blink(struct led_classdev *led_cdev,
unsigned long delay_on,
unsigned long delay_off)
{
int current_brightness;
current_brightness = led_get_brightness(led_cdev);
if (current_brightness)
led_cdev->blink_brightness = current_brightness;
if (!led_cdev->blink_brightness)
led_cdev->blink_brightness = led_cdev->max_brightness;
led_cdev->blink_delay_on = delay_on;
led_cdev->blink_delay_off = delay_off;
/* never on - just set to off */
if (!delay_on) {
led_set_brightness_nosleep(led_cdev, LED_OFF);
return;
}
/* never off - just set to brightness */
if (!delay_off) {
led_set_brightness_nosleep(led_cdev,
led_cdev->blink_brightness);
return;
}
set_bit(LED_BLINK_SW, &led_cdev->work_flags);
mod_timer(&led_cdev->blink_timer, jiffies + 1);
}
static void led_blink_setup(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off)
{
if (!test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
led_cdev->blink_set &&
!led_cdev->blink_set(led_cdev, delay_on, delay_off))
return;
/* blink with 1 Hz as default if nothing specified */
if (!*delay_on && !*delay_off)
*delay_on = *delay_off = 500;
led_set_software_blink(led_cdev, *delay_on, *delay_off);
}
void led_init_core(struct led_classdev *led_cdev)
{
INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
timer_setup(&led_cdev->blink_timer, led_timer_function, 0);
}
EXPORT_SYMBOL_GPL(led_init_core);
void led_blink_set(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off)
{
del_timer_sync(&led_cdev->blink_timer);
clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
led_blink_setup(led_cdev, delay_on, delay_off);
}
EXPORT_SYMBOL_GPL(led_blink_set);
void led_blink_set_oneshot(struct led_classdev *led_cdev,
unsigned long *delay_on,
unsigned long *delay_off,
int invert)
{
if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
timer_pending(&led_cdev->blink_timer))
return;
set_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
if (invert)
set_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
else
clear_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
led_blink_setup(led_cdev, delay_on, delay_off);
}
EXPORT_SYMBOL_GPL(led_blink_set_oneshot);
void led_stop_software_blink(struct led_classdev *led_cdev)
{
del_timer_sync(&led_cdev->blink_timer);
led_cdev->blink_delay_on = 0;
led_cdev->blink_delay_off = 0;
clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
}
EXPORT_SYMBOL_GPL(led_stop_software_blink);
void led_set_brightness(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
/*
* If software blink is active, delay brightness setting
* until the next timer tick.
*/
if (test_bit(LED_BLINK_SW, &led_cdev->work_flags)) {
/*
* If we need to disable soft blinking delegate this to the
* work queue task to avoid problems in case we are called
* from hard irq context.
*/
if (brightness == LED_OFF) {
set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags);
schedule_work(&led_cdev->set_brightness_work);
} else {
set_bit(LED_BLINK_BRIGHTNESS_CHANGE,
&led_cdev->work_flags);
led_cdev->new_blink_brightness = brightness;
}
return;
}
led_set_brightness_nosleep(led_cdev, brightness);
}
EXPORT_SYMBOL_GPL(led_set_brightness);
void led_set_brightness_nopm(struct led_classdev *led_cdev,
enum led_brightness value)
{
/* Use brightness_set op if available, it is guaranteed not to sleep */
if (!__led_set_brightness(led_cdev, value))
return;
/* If brightness setting can sleep, delegate it to a work queue task */
led_cdev->delayed_set_value = value;
schedule_work(&led_cdev->set_brightness_work);
}
EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
void led_set_brightness_nosleep(struct led_classdev *led_cdev,
enum led_brightness value)
{
led_cdev->brightness = min(value, led_cdev->max_brightness);
if (led_cdev->flags & LED_SUSPENDED)
return;
led_set_brightness_nopm(led_cdev, led_cdev->brightness);
}
EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);
int led_set_brightness_sync(struct led_classdev *led_cdev,
enum led_brightness value)
{
if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
return -EBUSY;
led_cdev->brightness = min(value, led_cdev->max_brightness);
if (led_cdev->flags & LED_SUSPENDED)
return 0;
return __led_set_brightness_blocking(led_cdev, led_cdev->brightness);
}
EXPORT_SYMBOL_GPL(led_set_brightness_sync);
int led_update_brightness(struct led_classdev *led_cdev)
{
int ret = 0;
if (led_cdev->brightness_get) {
ret = led_cdev->brightness_get(led_cdev);
if (ret >= 0) {
led_cdev->brightness = ret;
return 0;
}
}
return ret;
}
EXPORT_SYMBOL_GPL(led_update_brightness);
u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size)
{
struct fwnode_handle *fwnode = led_cdev->dev->fwnode;
u32 *pattern;
int count;
count = fwnode_property_count_u32(fwnode, "led-pattern");
if (count < 0)
return NULL;
pattern = kcalloc(count, sizeof(*pattern), GFP_KERNEL);
if (!pattern)
return NULL;
if (fwnode_property_read_u32_array(fwnode, "led-pattern", pattern, count)) {
kfree(pattern);
return NULL;
}
*size = count;
return pattern;
}
EXPORT_SYMBOL_GPL(led_get_default_pattern);
/* Caller must ensure led_cdev->led_access held */
void led_sysfs_disable(struct led_classdev *led_cdev)
{
lockdep_assert_held(&led_cdev->led_access);
led_cdev->flags |= LED_SYSFS_DISABLE;
}
EXPORT_SYMBOL_GPL(led_sysfs_disable);
/* Caller must ensure led_cdev->led_access held */
void led_sysfs_enable(struct led_classdev *led_cdev)
{
lockdep_assert_held(&led_cdev->led_access);
led_cdev->flags &= ~LED_SYSFS_DISABLE;
}
EXPORT_SYMBOL_GPL(led_sysfs_enable);
static void led_parse_fwnode_props(struct device *dev,
struct fwnode_handle *fwnode,
struct led_properties *props)
{
int ret;
if (!fwnode)
return;
if (fwnode_property_present(fwnode, "label")) {
ret = fwnode_property_read_string(fwnode, "label", &props->label);
if (ret)
dev_err(dev, "Error parsing 'label' property (%d)\n", ret);
return;
}
if (fwnode_property_present(fwnode, "color")) {
ret = fwnode_property_read_u32(fwnode, "color", &props->color);
if (ret)
dev_err(dev, "Error parsing 'color' property (%d)\n", ret);
else if (props->color >= LED_COLOR_ID_MAX)
dev_err(dev, "LED color identifier out of range\n");
else
props->color_present = true;
}
if (!fwnode_property_present(fwnode, "function"))
return;
ret = fwnode_property_read_string(fwnode, "function", &props->function);
if (ret) {
dev_err(dev,
"Error parsing 'function' property (%d)\n",
ret);
}
if (!fwnode_property_present(fwnode, "function-enumerator"))
return;
ret = fwnode_property_read_u32(fwnode, "function-enumerator",
&props->func_enum);
if (ret) {
dev_err(dev,
"Error parsing 'function-enumerator' property (%d)\n",
ret);
} else {
props->func_enum_present = true;
}
}
int led_compose_name(struct device *dev, struct led_init_data *init_data,
char *led_classdev_name)
{
struct led_properties props = {};
struct fwnode_handle *fwnode = init_data->fwnode;
const char *devicename = init_data->devicename;
if (!led_classdev_name)
return -EINVAL;
led_parse_fwnode_props(dev, fwnode, &props);
if (props.label) {
/*
* If init_data.devicename is NULL, then it indicates that
* DT label should be used as-is for LED class device name.
* Otherwise the label is prepended with devicename to compose
* the final LED class device name.
*/
if (!devicename) {
strscpy(led_classdev_name, props.label,
LED_MAX_NAME_SIZE);
} else {
snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
devicename, props.label);
}
} else if (props.function || props.color_present) {
char tmp_buf[LED_MAX_NAME_SIZE];
if (props.func_enum_present) {
snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s-%d",
props.color_present ? led_colors[props.color] : "",
props.function ?: "", props.func_enum);
} else {
snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s",
props.color_present ? led_colors[props.color] : "",
props.function ?: "");
}
if (init_data->devname_mandatory) {
snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
devicename, tmp_buf);
} else {
strscpy(led_classdev_name, tmp_buf, LED_MAX_NAME_SIZE);
}
} else if (init_data->default_label) {
if (!devicename) {
dev_err(dev, "Legacy LED naming requires devicename segment");
return -EINVAL;
}
snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
devicename, init_data->default_label);
} else if (is_of_node(fwnode)) {
strscpy(led_classdev_name, to_of_node(fwnode)->name,
LED_MAX_NAME_SIZE);
} else
return -EINVAL;
return 0;
}
EXPORT_SYMBOL_GPL(led_compose_name);