1 /* drivers/leds/leds-s3c24xx.c
2 *
3 * (c) 2006 Simtec Electronics
4 * http://armlinux.simtec.co.uk/
5 * Ben Dooks <ben@simtec.co.uk>
6 *
7 * S3C24XX - LEDs GPIO driver
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14 #include <linux/kernel.h>
15 #include <linux/platform_device.h>
16 #include <linux/leds.h>
17 #include <linux/gpio.h>
18 #include <linux/slab.h>
19 #include <linux/module.h>
20 #include <linux/platform_data/leds-s3c24xx.h>
21
22 #include <mach/regs-gpio.h>
23 #include <plat/gpio-cfg.h>
24
25 /* our context */
26
27 struct s3c24xx_gpio_led {
28 struct led_classdev cdev;
29 struct s3c24xx_led_platdata *pdata;
30 };
31
to_gpio(struct led_classdev * led_cdev)32 static inline struct s3c24xx_gpio_led *to_gpio(struct led_classdev *led_cdev)
33 {
34 return container_of(led_cdev, struct s3c24xx_gpio_led, cdev);
35 }
36
s3c24xx_led_set(struct led_classdev * led_cdev,enum led_brightness value)37 static void s3c24xx_led_set(struct led_classdev *led_cdev,
38 enum led_brightness value)
39 {
40 struct s3c24xx_gpio_led *led = to_gpio(led_cdev);
41 struct s3c24xx_led_platdata *pd = led->pdata;
42 int state = (value ? 1 : 0) ^ (pd->flags & S3C24XX_LEDF_ACTLOW);
43
44 /* there will be a short delay between setting the output and
45 * going from output to input when using tristate. */
46
47 gpio_set_value(pd->gpio, state);
48
49 if (pd->flags & S3C24XX_LEDF_TRISTATE) {
50 if (value)
51 gpio_direction_output(pd->gpio, state);
52 else
53 gpio_direction_input(pd->gpio);
54 }
55 }
56
s3c24xx_led_probe(struct platform_device * dev)57 static int s3c24xx_led_probe(struct platform_device *dev)
58 {
59 struct s3c24xx_led_platdata *pdata = dev_get_platdata(&dev->dev);
60 struct s3c24xx_gpio_led *led;
61 int ret;
62
63 led = devm_kzalloc(&dev->dev, sizeof(struct s3c24xx_gpio_led),
64 GFP_KERNEL);
65 if (!led)
66 return -ENOMEM;
67
68 led->cdev.brightness_set = s3c24xx_led_set;
69 led->cdev.default_trigger = pdata->def_trigger;
70 led->cdev.name = pdata->name;
71 led->cdev.flags |= LED_CORE_SUSPENDRESUME;
72
73 led->pdata = pdata;
74
75 ret = devm_gpio_request(&dev->dev, pdata->gpio, "S3C24XX_LED");
76 if (ret < 0)
77 return ret;
78
79 /* no point in having a pull-up if we are always driving */
80
81 s3c_gpio_setpull(pdata->gpio, S3C_GPIO_PULL_NONE);
82
83 if (pdata->flags & S3C24XX_LEDF_TRISTATE)
84 gpio_direction_input(pdata->gpio);
85 else
86 gpio_direction_output(pdata->gpio,
87 pdata->flags & S3C24XX_LEDF_ACTLOW ? 1 : 0);
88
89 /* register our new led device */
90
91 ret = devm_led_classdev_register(&dev->dev, &led->cdev);
92 if (ret < 0)
93 dev_err(&dev->dev, "led_classdev_register failed\n");
94
95 return ret;
96 }
97
98 static struct platform_driver s3c24xx_led_driver = {
99 .probe = s3c24xx_led_probe,
100 .driver = {
101 .name = "s3c24xx_led",
102 },
103 };
104
105 module_platform_driver(s3c24xx_led_driver);
106
107 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
108 MODULE_DESCRIPTION("S3C24XX LED driver");
109 MODULE_LICENSE("GPL");
110 MODULE_ALIAS("platform:s3c24xx_led");
111
