tegrakernel/kernel/kernel-4.9/drivers/leds/leds-s3c24xx.c

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2022-02-16 09:13:02 -06:00
/* drivers/leds/leds-s3c24xx.c
*
* (c) 2006 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* S3C24XX - LEDs GPIO driver
*
* 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/kernel.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/platform_data/leds-s3c24xx.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-cfg.h>
/* our context */
struct s3c24xx_gpio_led {
struct led_classdev cdev;
struct s3c24xx_led_platdata *pdata;
};
static inline struct s3c24xx_gpio_led *to_gpio(struct led_classdev *led_cdev)
{
return container_of(led_cdev, struct s3c24xx_gpio_led, cdev);
}
static void s3c24xx_led_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
struct s3c24xx_gpio_led *led = to_gpio(led_cdev);
struct s3c24xx_led_platdata *pd = led->pdata;
int state = (value ? 1 : 0) ^ (pd->flags & S3C24XX_LEDF_ACTLOW);
/* there will be a short delay between setting the output and
* going from output to input when using tristate. */
gpio_set_value(pd->gpio, state);
if (pd->flags & S3C24XX_LEDF_TRISTATE) {
if (value)
gpio_direction_output(pd->gpio, state);
else
gpio_direction_input(pd->gpio);
}
}
static int s3c24xx_led_probe(struct platform_device *dev)
{
struct s3c24xx_led_platdata *pdata = dev_get_platdata(&dev->dev);
struct s3c24xx_gpio_led *led;
int ret;
led = devm_kzalloc(&dev->dev, sizeof(struct s3c24xx_gpio_led),
GFP_KERNEL);
if (!led)
return -ENOMEM;
led->cdev.brightness_set = s3c24xx_led_set;
led->cdev.default_trigger = pdata->def_trigger;
led->cdev.name = pdata->name;
led->cdev.flags |= LED_CORE_SUSPENDRESUME;
led->pdata = pdata;
ret = devm_gpio_request(&dev->dev, pdata->gpio, "S3C24XX_LED");
if (ret < 0)
return ret;
/* no point in having a pull-up if we are always driving */
s3c_gpio_setpull(pdata->gpio, S3C_GPIO_PULL_NONE);
if (pdata->flags & S3C24XX_LEDF_TRISTATE)
gpio_direction_input(pdata->gpio);
else
gpio_direction_output(pdata->gpio,
pdata->flags & S3C24XX_LEDF_ACTLOW ? 1 : 0);
/* register our new led device */
ret = devm_led_classdev_register(&dev->dev, &led->cdev);
if (ret < 0)
dev_err(&dev->dev, "led_classdev_register failed\n");
return ret;
}
static struct platform_driver s3c24xx_led_driver = {
.probe = s3c24xx_led_probe,
.driver = {
.name = "s3c24xx_led",
},
};
module_platform_driver(s3c24xx_led_driver);
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_DESCRIPTION("S3C24XX LED driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:s3c24xx_led");