1 | /* |
2 | * Bachmann ot200 leds driver. |
3 | * |
4 | * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> |
5 | * Christian Gmeiner <christian.gmeiner@gmail.com> |
6 | * |
7 | * License: GPL as published by the FSF. |
8 | */ |
9 | |
10 | #include <linux/kernel.h> |
11 | #include <linux/platform_device.h> |
12 | #include <linux/slab.h> |
13 | #include <linux/leds.h> |
14 | #include <linux/io.h> |
15 | #include <linux/module.h> |
16 | |
17 | |
18 | struct ot200_led { |
19 | struct led_classdev cdev; |
20 | const char *name; |
21 | unsigned long port; |
22 | u8 mask; |
23 | }; |
24 | |
25 | /* |
26 | * The device has three leds on the back panel (led_err, led_init and led_run) |
27 | * and can handle up to seven leds on the front panel. |
28 | */ |
29 | |
30 | static struct ot200_led leds[] = { |
31 | { |
32 | .name = "led_run" , |
33 | .port = 0x5a, |
34 | .mask = BIT(0), |
35 | }, |
36 | { |
37 | .name = "led_init" , |
38 | .port = 0x5a, |
39 | .mask = BIT(1), |
40 | }, |
41 | { |
42 | .name = "led_err" , |
43 | .port = 0x5a, |
44 | .mask = BIT(2), |
45 | }, |
46 | { |
47 | .name = "led_1" , |
48 | .port = 0x49, |
49 | .mask = BIT(6), |
50 | }, |
51 | { |
52 | .name = "led_2" , |
53 | .port = 0x49, |
54 | .mask = BIT(5), |
55 | }, |
56 | { |
57 | .name = "led_3" , |
58 | .port = 0x49, |
59 | .mask = BIT(4), |
60 | }, |
61 | { |
62 | .name = "led_4" , |
63 | .port = 0x49, |
64 | .mask = BIT(3), |
65 | }, |
66 | { |
67 | .name = "led_5" , |
68 | .port = 0x49, |
69 | .mask = BIT(2), |
70 | }, |
71 | { |
72 | .name = "led_6" , |
73 | .port = 0x49, |
74 | .mask = BIT(1), |
75 | }, |
76 | { |
77 | .name = "led_7" , |
78 | .port = 0x49, |
79 | .mask = BIT(0), |
80 | } |
81 | }; |
82 | |
83 | static DEFINE_SPINLOCK(value_lock); |
84 | |
85 | /* |
86 | * we need to store the current led states, as it is not |
87 | * possible to read the current led state via inb(). |
88 | */ |
89 | static u8 leds_back; |
90 | static u8 leds_front; |
91 | |
92 | static void ot200_led_brightness_set(struct led_classdev *led_cdev, |
93 | enum led_brightness value) |
94 | { |
95 | struct ot200_led *led = container_of(led_cdev, struct ot200_led, cdev); |
96 | u8 *val; |
97 | unsigned long flags; |
98 | |
99 | spin_lock_irqsave(&value_lock, flags); |
100 | |
101 | if (led->port == 0x49) |
102 | val = &leds_front; |
103 | else if (led->port == 0x5a) |
104 | val = &leds_back; |
105 | else |
106 | BUG(); |
107 | |
108 | if (value == LED_OFF) |
109 | *val &= ~led->mask; |
110 | else |
111 | *val |= led->mask; |
112 | |
113 | outb(value: *val, port: led->port); |
114 | spin_unlock_irqrestore(lock: &value_lock, flags); |
115 | } |
116 | |
117 | static int ot200_led_probe(struct platform_device *pdev) |
118 | { |
119 | int i; |
120 | int ret; |
121 | |
122 | for (i = 0; i < ARRAY_SIZE(leds); i++) { |
123 | |
124 | leds[i].cdev.name = leds[i].name; |
125 | leds[i].cdev.brightness_set = ot200_led_brightness_set; |
126 | |
127 | ret = devm_led_classdev_register(parent: &pdev->dev, led_cdev: &leds[i].cdev); |
128 | if (ret < 0) |
129 | return ret; |
130 | } |
131 | |
132 | leds_front = 0; /* turn off all front leds */ |
133 | leds_back = BIT(1); /* turn on init led */ |
134 | outb(value: leds_front, port: 0x49); |
135 | outb(value: leds_back, port: 0x5a); |
136 | |
137 | return 0; |
138 | } |
139 | |
140 | static struct platform_driver ot200_led_driver = { |
141 | .probe = ot200_led_probe, |
142 | .driver = { |
143 | .name = "leds-ot200" , |
144 | }, |
145 | }; |
146 | |
147 | module_platform_driver(ot200_led_driver); |
148 | |
149 | MODULE_AUTHOR("Sebastian A. Siewior <bigeasy@linutronix.de>" ); |
150 | MODULE_DESCRIPTION("ot200 LED driver" ); |
151 | MODULE_LICENSE("GPL" ); |
152 | MODULE_ALIAS("platform:leds-ot200" ); |
153 | |