xref: /linux/drivers/leds/leds-ip30.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * LED Driver for SGI Octane machines
4  */
5 
6 #include <asm/io.h>
7 #include <linux/module.h>
8 #include <linux/kernel.h>
9 #include <linux/platform_device.h>
10 #include <linux/leds.h>
11 
12 #define IP30_LED_SYSTEM	0
13 #define IP30_LED_FAULT	1
14 
15 struct ip30_led {
16 	struct led_classdev cdev;
17 	u32 __iomem *reg;
18 };
19 
20 static void ip30led_set(struct led_classdev *led_cdev,
21 			enum led_brightness value)
22 {
23 	struct ip30_led *led = container_of(led_cdev, struct ip30_led, cdev);
24 
25 	writel(value, led->reg);
26 }
27 
28 static int ip30led_create(struct platform_device *pdev, int num)
29 {
30 	struct ip30_led *data;
31 
32 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
33 	if (!data)
34 		return -ENOMEM;
35 
36 	data->reg = devm_platform_ioremap_resource(pdev, num);
37 	if (IS_ERR(data->reg))
38 		return PTR_ERR(data->reg);
39 
40 	switch (num) {
41 	case IP30_LED_SYSTEM:
42 		data->cdev.name = "white:power";
43 		break;
44 	case IP30_LED_FAULT:
45 		data->cdev.name = "red:fault";
46 		break;
47 	default:
48 		return -EINVAL;
49 	}
50 
51 	data->cdev.brightness = readl(data->reg);
52 	data->cdev.max_brightness = 1;
53 	data->cdev.brightness_set = ip30led_set;
54 
55 	return devm_led_classdev_register(&pdev->dev, &data->cdev);
56 }
57 
58 static int ip30led_probe(struct platform_device *pdev)
59 {
60 	int ret;
61 
62 	ret = ip30led_create(pdev, IP30_LED_SYSTEM);
63 	if (ret < 0)
64 		return ret;
65 
66 	return ip30led_create(pdev, IP30_LED_FAULT);
67 }
68 
69 static struct platform_driver ip30led_driver = {
70 	.probe		= ip30led_probe,
71 	.driver		= {
72 		.name		= "ip30-leds",
73 	},
74 };
75 
76 module_platform_driver(ip30led_driver);
77 
78 MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@suse.de>");
79 MODULE_DESCRIPTION("SGI Octane LED driver");
80 MODULE_LICENSE("GPL");
81 MODULE_ALIAS("platform:ip30-leds");
82