summaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-s3c24xx.c
blob: 87cf215af798c97076df857b0609292c1f752cfe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/* 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/init.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/module.h>

#include <mach/hardware.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-cfg.h>
#include <linux/platform_data/leds-s3c24xx.h>

/* our context */

struct s3c24xx_gpio_led {
	struct led_classdev		 cdev;
	struct s3c24xx_led_platdata	*pdata;
};

static inline struct s3c24xx_gpio_led *pdev_to_gpio(struct platform_device *dev)
{
	return platform_get_drvdata(dev);
}

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_remove(struct platform_device *dev)
{
	struct s3c24xx_gpio_led *led = pdev_to_gpio(dev);

	led_classdev_unregister(&led->cdev);

	return 0;
}

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 == NULL) {
		dev_err(&dev->dev, "No memory for device\n");
		return -ENOMEM;
	}

	platform_set_drvdata(dev, led);

	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 = 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,
	.remove		= s3c24xx_led_remove,
	.driver		= {
		.name		= "s3c24xx_led",
		.owner		= THIS_MODULE,
	},
};

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");