1 /*
2 * Driver for the 8 user LEDs found on the RealViews and Versatiles
3 * Based on DaVinci's DM365 board code
4 *
5 * License terms: GNU General Public License (GPL) version 2
6 * Author: Linus Walleij <triad@df.lth.se>
7 */
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/io.h>
11 #include <linux/slab.h>
12 #include <linux/leds.h>
13
14 #include <mach/hardware.h>
15 #include <mach/platform.h>
16
17 #ifdef VERSATILE_SYS_BASE
18 #define LEDREG (__io_address(VERSATILE_SYS_BASE) + VERSATILE_SYS_LED_OFFSET)
19 #endif
20
21 #ifdef REALVIEW_SYS_BASE
22 #define LEDREG (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_LED_OFFSET)
23 #endif
24
25 struct versatile_led {
26 struct led_classdev cdev;
27 u8 mask;
28 };
29
30 /*
31 * The triggers lines up below will only be used if the
32 * LED triggers are compiled in.
33 */
34 static const struct {
35 const char *name;
36 const char *trigger;
37 } versatile_leds[] = {
38 { "versatile:0", "heartbeat", },
39 { "versatile:1", "mmc0", },
40 { "versatile:2", },
41 { "versatile:3", },
42 { "versatile:4", },
43 { "versatile:5", },
44 { "versatile:6", },
45 { "versatile:7", },
46 };
47
versatile_led_set(struct led_classdev * cdev,enum led_brightness b)48 static void versatile_led_set(struct led_classdev *cdev,
49 enum led_brightness b)
50 {
51 struct versatile_led *led = container_of(cdev,
52 struct versatile_led, cdev);
53 u32 reg = readl(LEDREG);
54
55 if (b != LED_OFF)
56 reg |= led->mask;
57 else
58 reg &= ~led->mask;
59 writel(reg, LEDREG);
60 }
61
versatile_led_get(struct led_classdev * cdev)62 static enum led_brightness versatile_led_get(struct led_classdev *cdev)
63 {
64 struct versatile_led *led = container_of(cdev,
65 struct versatile_led, cdev);
66 u32 reg = readl(LEDREG);
67
68 return (reg & led->mask) ? LED_FULL : LED_OFF;
69 }
70
versatile_leds_init(void)71 static int __init versatile_leds_init(void)
72 {
73 int i;
74
75 /* All ON */
76 writel(0xff, LEDREG);
77 for (i = 0; i < ARRAY_SIZE(versatile_leds); i++) {
78 struct versatile_led *led;
79
80 led = kzalloc(sizeof(*led), GFP_KERNEL);
81 if (!led)
82 break;
83
84 led->cdev.name = versatile_leds[i].name;
85 led->cdev.brightness_set = versatile_led_set;
86 led->cdev.brightness_get = versatile_led_get;
87 led->cdev.default_trigger = versatile_leds[i].trigger;
88 led->mask = BIT(i);
89
90 if (led_classdev_register(NULL, &led->cdev) < 0) {
91 kfree(led);
92 break;
93 }
94 }
95
96 return 0;
97 }
98
99 /*
100 * Since we may have triggers on any subsystem, defer registration
101 * until after subsystem_init.
102 */
103 fs_initcall(versatile_leds_init);
104