1// SPDX-License-Identifier: GPL-2.0-only
  2/* drivers/leds/leds-s3c24xx.c
  3 *
  4 * (c) 2006 Simtec Electronics
  5 *	http://armlinux.simtec.co.uk/
  6 *	Ben Dooks <ben@simtec.co.uk>
  7 *
  8 * S3C24XX - LEDs GPIO driver
  9*/
 10
 11#include <linux/kernel.h>
 12#include <linux/platform_device.h>
 13#include <linux/leds.h>
 14#include <linux/gpio.h>
 15#include <linux/slab.h>
 16#include <linux/module.h>
 17#include <linux/platform_data/leds-s3c24xx.h>
 18
 19#include <mach/regs-gpio.h>
 20#include <plat/gpio-cfg.h>
 21
 22/* our context */
 23
 24struct s3c24xx_gpio_led {
 25	struct led_classdev		 cdev;
 26	struct s3c24xx_led_platdata	*pdata;
 27};
 28
 29static inline struct s3c24xx_gpio_led *to_gpio(struct led_classdev *led_cdev)
 30{
 31	return container_of(led_cdev, struct s3c24xx_gpio_led, cdev);
 32}
 33
 34static void s3c24xx_led_set(struct led_classdev *led_cdev,
 35			    enum led_brightness value)
 36{
 37	struct s3c24xx_gpio_led *led = to_gpio(led_cdev);
 38	struct s3c24xx_led_platdata *pd = led->pdata;
 39	int state = (value ? 1 : 0) ^ (pd->flags & S3C24XX_LEDF_ACTLOW);
 40
 41	/* there will be a short delay between setting the output and
 42	 * going from output to input when using tristate. */
 43
 44	gpio_set_value(pd->gpio, state);
 45
 46	if (pd->flags & S3C24XX_LEDF_TRISTATE) {
 47		if (value)
 48			gpio_direction_output(pd->gpio, state);
 49		else
 50			gpio_direction_input(pd->gpio);
 51	}
 52}
 53
 54static int s3c24xx_led_probe(struct platform_device *dev)
 55{
 56	struct s3c24xx_led_platdata *pdata = dev_get_platdata(&dev->dev);
 57	struct s3c24xx_gpio_led *led;
 58	int ret;
 59
 60	led = devm_kzalloc(&dev->dev, sizeof(struct s3c24xx_gpio_led),
 61			   GFP_KERNEL);
 62	if (!led)
 63		return -ENOMEM;
 64
 65	led->cdev.brightness_set = s3c24xx_led_set;
 66	led->cdev.default_trigger = pdata->def_trigger;
 67	led->cdev.name = pdata->name;
 68	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
 69
 70	led->pdata = pdata;
 71
 72	ret = devm_gpio_request(&dev->dev, pdata->gpio, "S3C24XX_LED");
 73	if (ret < 0)
 74		return ret;
 75
 76	/* no point in having a pull-up if we are always driving */
 77
 78	s3c_gpio_setpull(pdata->gpio, S3C_GPIO_PULL_NONE);
 79
 80	if (pdata->flags & S3C24XX_LEDF_TRISTATE)
 81		gpio_direction_input(pdata->gpio);
 82	else
 83		gpio_direction_output(pdata->gpio,
 84			pdata->flags & S3C24XX_LEDF_ACTLOW ? 1 : 0);
 85
 86	/* register our new led device */
 87
 88	ret = devm_led_classdev_register(&dev->dev, &led->cdev);
 89	if (ret < 0)
 90		dev_err(&dev->dev, "led_classdev_register failed\n");
 91
 92	return ret;
 93}
 94
 95static struct platform_driver s3c24xx_led_driver = {
 96	.probe		= s3c24xx_led_probe,
 97	.driver		= {
 98		.name		= "s3c24xx_led",
 99	},
100};
101
102module_platform_driver(s3c24xx_led_driver);
103
104MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
105MODULE_DESCRIPTION("S3C24XX LED driver");
106MODULE_LICENSE("GPL");
107MODULE_ALIAS("platform:s3c24xx_led");