1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/arm/mach-footbridge/ebsa285.c
4 *
5 * EBSA285 machine fixup
6 */
7#include <linux/init.h>
8#include <linux/io.h>
9#include <linux/spinlock.h>
10#include <linux/slab.h>
11#include <linux/leds.h>
12
13#include <asm/hardware/dec21285.h>
14#include <asm/mach-types.h>
15
16#include <asm/mach/arch.h>
17
18#include "common.h"
19
20/* LEDs */
21#if defined(CONFIG_NEW_LEDS) && defined(CONFIG_LEDS_CLASS)
22#define XBUS_AMBER_L BIT(0)
23#define XBUS_GREEN_L BIT(1)
24#define XBUS_RED_L BIT(2)
25#define XBUS_TOGGLE BIT(7)
26
27struct ebsa285_led {
28 struct led_classdev cdev;
29 u8 mask;
30};
31
32/*
33 * The triggers lines up below will only be used if the
34 * LED triggers are compiled in.
35 */
36static const struct {
37 const char *name;
38 const char *trigger;
39} ebsa285_leds[] = {
40 { "ebsa285:amber", "cpu0", },
41 { "ebsa285:green", "heartbeat", },
42 { "ebsa285:red",},
43};
44
45static unsigned char hw_led_state;
46static void __iomem *xbus;
47
48static void ebsa285_led_set(struct led_classdev *cdev,
49 enum led_brightness b)
50{
51 struct ebsa285_led *led = container_of(cdev,
52 struct ebsa285_led, cdev);
53
54 if (b == LED_OFF)
55 hw_led_state |= led->mask;
56 else
57 hw_led_state &= ~led->mask;
58 writeb(val: hw_led_state, addr: xbus);
59}
60
61static enum led_brightness ebsa285_led_get(struct led_classdev *cdev)
62{
63 struct ebsa285_led *led = container_of(cdev,
64 struct ebsa285_led, cdev);
65
66 return hw_led_state & led->mask ? LED_OFF : LED_FULL;
67}
68
69static int __init ebsa285_leds_init(void)
70{
71 int i;
72
73 if (!machine_is_ebsa285())
74 return -ENODEV;
75
76 xbus = ioremap(offset: XBUS_CS2, size: SZ_4K);
77 if (!xbus)
78 return -ENOMEM;
79
80 /* 3 LEDS all off */
81 hw_led_state = XBUS_AMBER_L | XBUS_GREEN_L | XBUS_RED_L;
82 writeb(val: hw_led_state, addr: xbus);
83
84 for (i = 0; i < ARRAY_SIZE(ebsa285_leds); i++) {
85 struct ebsa285_led *led;
86
87 led = kzalloc(size: sizeof(*led), GFP_KERNEL);
88 if (!led)
89 break;
90
91 led->cdev.name = ebsa285_leds[i].name;
92 led->cdev.brightness_set = ebsa285_led_set;
93 led->cdev.brightness_get = ebsa285_led_get;
94 led->cdev.default_trigger = ebsa285_leds[i].trigger;
95 led->mask = BIT(i);
96
97 if (led_classdev_register(NULL, led_cdev: &led->cdev) < 0) {
98 kfree(objp: led);
99 break;
100 }
101 }
102
103 return 0;
104}
105
106/*
107 * Since we may have triggers on any subsystem, defer registration
108 * until after subsystem_init.
109 */
110fs_initcall(ebsa285_leds_init);
111#endif
112
113MACHINE_START(EBSA285, "EBSA285")
114 /* Maintainer: Russell King */
115 .atag_offset = 0x100,
116 .video_start = 0x000a0000,
117 .video_end = 0x000bffff,
118 .map_io = footbridge_map_io,
119 .init_early = footbridge_sched_clock,
120 .init_irq = footbridge_init_irq,
121 .init_time = footbridge_timer_init,
122 .restart = footbridge_restart,
123MACHINE_END
124
125

source code of linux/arch/arm/mach-footbridge/ebsa285.c