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
pdev_to_gpio(struct platform_device * dev)32 static inline struct s3c24xx_gpio_led *pdev_to_gpio(struct platform_device *dev)
33 {
34 return platform_get_drvdata(dev);
35 }
36
to_gpio(struct led_classdev * led_cdev)37 static inline struct s3c24xx_gpio_led *to_gpio(struct led_classdev *led_cdev)
38 {
39 return container_of(led_cdev, struct s3c24xx_gpio_led, cdev);
40 }
41
s3c24xx_led_set(struct led_classdev * led_cdev,enum led_brightness value)42 static void s3c24xx_led_set(struct led_classdev *led_cdev,
43 enum led_brightness value)
44 {
45 struct s3c24xx_gpio_led *led = to_gpio(led_cdev);
46 struct s3c24xx_led_platdata *pd = led->pdata;
47 int state = (value ? 1 : 0) ^ (pd->flags & S3C24XX_LEDF_ACTLOW);
48
49 /* there will be a short delay between setting the output and
50 * going from output to input when using tristate. */
51
52 gpio_set_value(pd->gpio, state);
53
54 if (pd->flags & S3C24XX_LEDF_TRISTATE) {
55 if (value)
56 gpio_direction_output(pd->gpio, state);
57 else
58 gpio_direction_input(pd->gpio);
59 }
60 }
61
s3c24xx_led_remove(struct platform_device * dev)62 static int s3c24xx_led_remove(struct platform_device *dev)
63 {
64 struct s3c24xx_gpio_led *led = pdev_to_gpio(dev);
65
66 led_classdev_unregister(&led->cdev);
67
68 return 0;
69 }
70
s3c24xx_led_probe(struct platform_device * dev)71 static int s3c24xx_led_probe(struct platform_device *dev)
72 {
73 struct s3c24xx_led_platdata *pdata = dev_get_platdata(&dev->dev);
74 struct s3c24xx_gpio_led *led;
75 int ret;
76
77 led = devm_kzalloc(&dev->dev, sizeof(struct s3c24xx_gpio_led),
78 GFP_KERNEL);
79 if (!led)
80 return -ENOMEM;
81
82 platform_set_drvdata(dev, led);
83
84 led->cdev.brightness_set = s3c24xx_led_set;
85 led->cdev.default_trigger = pdata->def_trigger;
86 led->cdev.name = pdata->name;
87 led->cdev.flags |= LED_CORE_SUSPENDRESUME;
88
89 led->pdata = pdata;
90
91 ret = devm_gpio_request(&dev->dev, pdata->gpio, "S3C24XX_LED");
92 if (ret < 0)
93 return ret;
94
95 /* no point in having a pull-up if we are always driving */
96
97 s3c_gpio_setpull(pdata->gpio, S3C_GPIO_PULL_NONE);
98
99 if (pdata->flags & S3C24XX_LEDF_TRISTATE)
100 gpio_direction_input(pdata->gpio);
101 else
102 gpio_direction_output(pdata->gpio,
103 pdata->flags & S3C24XX_LEDF_ACTLOW ? 1 : 0);
104
105 /* register our new led device */
106
107 ret = led_classdev_register(&dev->dev, &led->cdev);
108 if (ret < 0)
109 dev_err(&dev->dev, "led_classdev_register failed\n");
110
111 return ret;
112 }
113
114 static struct platform_driver s3c24xx_led_driver = {
115 .probe = s3c24xx_led_probe,
116 .remove = s3c24xx_led_remove,
117 .driver = {
118 .name = "s3c24xx_led",
119 .owner = THIS_MODULE,
120 },
121 };
122
123 module_platform_driver(s3c24xx_led_driver);
124
125 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
126 MODULE_DESCRIPTION("S3C24XX LED driver");
127 MODULE_LICENSE("GPL");
128 MODULE_ALIAS("platform:s3c24xx_led");
129