tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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");