linux-stable/drivers/leds/led-class-flash.c
Pavel Machek 654933ae7d leds: flash: Remove redundant initialization of variable ret
Adjust initialization not to trigger Coverity warnings.

Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
2021-08-16 08:47:08 +02:00

446 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* LED Flash class interface
*
* Copyright (C) 2015 Samsung Electronics Co., Ltd.
* Author: Jacek Anaszewski <j.anaszewski@samsung.com>
*/
#include <linux/device.h>
#include <linux/init.h>
#include <linux/led-class-flash.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/slab.h>
#include "leds.h"
#define has_flash_op(fled_cdev, op) \
(fled_cdev && fled_cdev->ops->op)
#define call_flash_op(fled_cdev, op, args...) \
((has_flash_op(fled_cdev, op)) ? \
(fled_cdev->ops->op(fled_cdev, args)) : \
-EINVAL)
static const char * const led_flash_fault_names[] = {
"led-over-voltage",
"flash-timeout-exceeded",
"controller-over-temperature",
"controller-short-circuit",
"led-power-supply-over-current",
"indicator-led-fault",
"led-under-voltage",
"controller-under-voltage",
"led-over-temperature",
};
static ssize_t flash_brightness_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
unsigned long state;
ssize_t ret;
mutex_lock(&led_cdev->led_access);
if (led_sysfs_is_disabled(led_cdev)) {
ret = -EBUSY;
goto unlock;
}
ret = kstrtoul(buf, 10, &state);
if (ret)
goto unlock;
ret = led_set_flash_brightness(fled_cdev, state);
if (ret < 0)
goto unlock;
ret = size;
unlock:
mutex_unlock(&led_cdev->led_access);
return ret;
}
static ssize_t flash_brightness_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
/* no lock needed for this */
led_update_flash_brightness(fled_cdev);
return sprintf(buf, "%u\n", fled_cdev->brightness.val);
}
static DEVICE_ATTR_RW(flash_brightness);
static ssize_t max_flash_brightness_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
return sprintf(buf, "%u\n", fled_cdev->brightness.max);
}
static DEVICE_ATTR_RO(max_flash_brightness);
static ssize_t flash_strobe_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
unsigned long state;
ssize_t ret = -EBUSY;
mutex_lock(&led_cdev->led_access);
if (led_sysfs_is_disabled(led_cdev))
goto unlock;
ret = kstrtoul(buf, 10, &state);
if (ret)
goto unlock;
if (state > 1) {
ret = -EINVAL;
goto unlock;
}
ret = led_set_flash_strobe(fled_cdev, state);
if (ret < 0)
goto unlock;
ret = size;
unlock:
mutex_unlock(&led_cdev->led_access);
return ret;
}
static ssize_t flash_strobe_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
bool state;
int ret;
/* no lock needed for this */
ret = led_get_flash_strobe(fled_cdev, &state);
if (ret < 0)
return ret;
return sprintf(buf, "%u\n", state);
}
static DEVICE_ATTR_RW(flash_strobe);
static ssize_t flash_timeout_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
unsigned long flash_timeout;
ssize_t ret;
mutex_lock(&led_cdev->led_access);
if (led_sysfs_is_disabled(led_cdev)) {
ret = -EBUSY;
goto unlock;
}
ret = kstrtoul(buf, 10, &flash_timeout);
if (ret)
goto unlock;
ret = led_set_flash_timeout(fled_cdev, flash_timeout);
if (ret < 0)
goto unlock;
ret = size;
unlock:
mutex_unlock(&led_cdev->led_access);
return ret;
}
static ssize_t flash_timeout_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
return sprintf(buf, "%u\n", fled_cdev->timeout.val);
}
static DEVICE_ATTR_RW(flash_timeout);
static ssize_t max_flash_timeout_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
return sprintf(buf, "%u\n", fled_cdev->timeout.max);
}
static DEVICE_ATTR_RO(max_flash_timeout);
static ssize_t flash_fault_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
u32 fault, mask = 0x1;
char *pbuf = buf;
int i, ret, buf_len;
ret = led_get_flash_fault(fled_cdev, &fault);
if (ret < 0)
return -EINVAL;
*buf = '\0';
for (i = 0; i < LED_NUM_FLASH_FAULTS; ++i) {
if (fault & mask) {
buf_len = sprintf(pbuf, "%s ",
led_flash_fault_names[i]);
pbuf += buf_len;
}
mask <<= 1;
}
return sprintf(buf, "%s\n", buf);
}
static DEVICE_ATTR_RO(flash_fault);
static struct attribute *led_flash_strobe_attrs[] = {
&dev_attr_flash_strobe.attr,
NULL,
};
static struct attribute *led_flash_timeout_attrs[] = {
&dev_attr_flash_timeout.attr,
&dev_attr_max_flash_timeout.attr,
NULL,
};
static struct attribute *led_flash_brightness_attrs[] = {
&dev_attr_flash_brightness.attr,
&dev_attr_max_flash_brightness.attr,
NULL,
};
static struct attribute *led_flash_fault_attrs[] = {
&dev_attr_flash_fault.attr,
NULL,
};
static const struct attribute_group led_flash_strobe_group = {
.attrs = led_flash_strobe_attrs,
};
static const struct attribute_group led_flash_timeout_group = {
.attrs = led_flash_timeout_attrs,
};
static const struct attribute_group led_flash_brightness_group = {
.attrs = led_flash_brightness_attrs,
};
static const struct attribute_group led_flash_fault_group = {
.attrs = led_flash_fault_attrs,
};
static void led_flash_resume(struct led_classdev *led_cdev)
{
struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
call_flash_op(fled_cdev, flash_brightness_set,
fled_cdev->brightness.val);
call_flash_op(fled_cdev, timeout_set, fled_cdev->timeout.val);
}
static void led_flash_init_sysfs_groups(struct led_classdev_flash *fled_cdev)
{
struct led_classdev *led_cdev = &fled_cdev->led_cdev;
const struct led_flash_ops *ops = fled_cdev->ops;
const struct attribute_group **flash_groups = fled_cdev->sysfs_groups;
int num_sysfs_groups = 0;
flash_groups[num_sysfs_groups++] = &led_flash_strobe_group;
if (ops->flash_brightness_set)
flash_groups[num_sysfs_groups++] = &led_flash_brightness_group;
if (ops->timeout_set)
flash_groups[num_sysfs_groups++] = &led_flash_timeout_group;
if (ops->fault_get)
flash_groups[num_sysfs_groups++] = &led_flash_fault_group;
led_cdev->groups = flash_groups;
}
int led_classdev_flash_register_ext(struct device *parent,
struct led_classdev_flash *fled_cdev,
struct led_init_data *init_data)
{
struct led_classdev *led_cdev;
const struct led_flash_ops *ops;
int ret;
if (!fled_cdev)
return -EINVAL;
led_cdev = &fled_cdev->led_cdev;
if (led_cdev->flags & LED_DEV_CAP_FLASH) {
if (!led_cdev->brightness_set_blocking)
return -EINVAL;
ops = fled_cdev->ops;
if (!ops || !ops->strobe_set)
return -EINVAL;
led_cdev->flash_resume = led_flash_resume;
/* Select the sysfs attributes to be created for the device */
led_flash_init_sysfs_groups(fled_cdev);
}
/* Register led class device */
ret = led_classdev_register_ext(parent, led_cdev, init_data);
if (ret < 0)
return ret;
return 0;
}
EXPORT_SYMBOL_GPL(led_classdev_flash_register_ext);
void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev)
{
if (!fled_cdev)
return;
led_classdev_unregister(&fled_cdev->led_cdev);
}
EXPORT_SYMBOL_GPL(led_classdev_flash_unregister);
static void devm_led_classdev_flash_release(struct device *dev, void *res)
{
led_classdev_flash_unregister(*(struct led_classdev_flash **)res);
}
int devm_led_classdev_flash_register_ext(struct device *parent,
struct led_classdev_flash *fled_cdev,
struct led_init_data *init_data)
{
struct led_classdev_flash **dr;
int ret;
dr = devres_alloc(devm_led_classdev_flash_release, sizeof(*dr),
GFP_KERNEL);
if (!dr)
return -ENOMEM;
ret = led_classdev_flash_register_ext(parent, fled_cdev, init_data);
if (ret) {
devres_free(dr);
return ret;
}
*dr = fled_cdev;
devres_add(parent, dr);
return 0;
}
EXPORT_SYMBOL_GPL(devm_led_classdev_flash_register_ext);
static int devm_led_classdev_flash_match(struct device *dev,
void *res, void *data)
{
struct led_classdev_flash **p = res;
if (WARN_ON(!p || !*p))
return 0;
return *p == data;
}
void devm_led_classdev_flash_unregister(struct device *dev,
struct led_classdev_flash *fled_cdev)
{
WARN_ON(devres_release(dev,
devm_led_classdev_flash_release,
devm_led_classdev_flash_match, fled_cdev));
}
EXPORT_SYMBOL_GPL(devm_led_classdev_flash_unregister);
static void led_clamp_align(struct led_flash_setting *s)
{
u32 v, offset;
v = s->val + s->step / 2;
v = clamp(v, s->min, s->max);
offset = v - s->min;
offset = s->step * (offset / s->step);
s->val = s->min + offset;
}
int led_set_flash_timeout(struct led_classdev_flash *fled_cdev, u32 timeout)
{
struct led_classdev *led_cdev = &fled_cdev->led_cdev;
struct led_flash_setting *s = &fled_cdev->timeout;
s->val = timeout;
led_clamp_align(s);
if (!(led_cdev->flags & LED_SUSPENDED))
return call_flash_op(fled_cdev, timeout_set, s->val);
return 0;
}
EXPORT_SYMBOL_GPL(led_set_flash_timeout);
int led_get_flash_fault(struct led_classdev_flash *fled_cdev, u32 *fault)
{
return call_flash_op(fled_cdev, fault_get, fault);
}
EXPORT_SYMBOL_GPL(led_get_flash_fault);
int led_set_flash_brightness(struct led_classdev_flash *fled_cdev,
u32 brightness)
{
struct led_classdev *led_cdev = &fled_cdev->led_cdev;
struct led_flash_setting *s = &fled_cdev->brightness;
s->val = brightness;
led_clamp_align(s);
if (!(led_cdev->flags & LED_SUSPENDED))
return call_flash_op(fled_cdev, flash_brightness_set, s->val);
return 0;
}
EXPORT_SYMBOL_GPL(led_set_flash_brightness);
int led_update_flash_brightness(struct led_classdev_flash *fled_cdev)
{
struct led_flash_setting *s = &fled_cdev->brightness;
u32 brightness;
if (has_flash_op(fled_cdev, flash_brightness_get)) {
int ret = call_flash_op(fled_cdev, flash_brightness_get,
&brightness);
if (ret < 0)
return ret;
s->val = brightness;
}
return 0;
}
EXPORT_SYMBOL_GPL(led_update_flash_brightness);
MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
MODULE_DESCRIPTION("LED Flash class interface");
MODULE_LICENSE("GPL v2");