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22#include <linux/kernel.h>
23#include <linux/init.h>
24#include <linux/slab.h>
25#include <linux/percpu.h>
26#include <linux/syscore_ops.h>
27#include <linux/rwsem.h>
28#include <linux/cpu.h>
29#include "../leds.h"
30
31#define MAX_NAME_LEN 8
32
33struct led_trigger_cpu {
34 char name[MAX_NAME_LEN];
35 struct led_trigger *_trig;
36};
37
38static DEFINE_PER_CPU(struct led_trigger_cpu, cpu_trig);
39
40
41
42
43
44
45
46
47void ledtrig_cpu(enum cpu_led_event ledevt)
48{
49 struct led_trigger_cpu *trig = this_cpu_ptr(&cpu_trig);
50
51
52 switch (ledevt) {
53 case CPU_LED_IDLE_END:
54 case CPU_LED_START:
55
56 led_trigger_event(trig->_trig, LED_FULL);
57 break;
58
59 case CPU_LED_IDLE_START:
60 case CPU_LED_STOP:
61 case CPU_LED_HALTED:
62
63 led_trigger_event(trig->_trig, LED_OFF);
64 break;
65
66 default:
67
68 break;
69 }
70}
71EXPORT_SYMBOL(ledtrig_cpu);
72
73static int ledtrig_cpu_syscore_suspend(void)
74{
75 ledtrig_cpu(CPU_LED_STOP);
76 return 0;
77}
78
79static void ledtrig_cpu_syscore_resume(void)
80{
81 ledtrig_cpu(CPU_LED_START);
82}
83
84static void ledtrig_cpu_syscore_shutdown(void)
85{
86 ledtrig_cpu(CPU_LED_HALTED);
87}
88
89static struct syscore_ops ledtrig_cpu_syscore_ops = {
90 .shutdown = ledtrig_cpu_syscore_shutdown,
91 .suspend = ledtrig_cpu_syscore_suspend,
92 .resume = ledtrig_cpu_syscore_resume,
93};
94
95static int ledtrig_cpu_notify(struct notifier_block *self,
96 unsigned long action, void *hcpu)
97{
98 switch (action & ~CPU_TASKS_FROZEN) {
99 case CPU_STARTING:
100 ledtrig_cpu(CPU_LED_START);
101 break;
102 case CPU_DYING:
103 ledtrig_cpu(CPU_LED_STOP);
104 break;
105 }
106
107 return NOTIFY_OK;
108}
109
110
111static struct notifier_block ledtrig_cpu_nb = {
112 .notifier_call = ledtrig_cpu_notify,
113};
114
115static int __init ledtrig_cpu_init(void)
116{
117 int cpu;
118
119
120 BUILD_BUG_ON(CONFIG_NR_CPUS > 9999);
121
122
123
124
125
126
127 for_each_possible_cpu(cpu) {
128 struct led_trigger_cpu *trig = &per_cpu(cpu_trig, cpu);
129
130 snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu);
131
132 led_trigger_register_simple(trig->name, &trig->_trig);
133 }
134
135 register_syscore_ops(&ledtrig_cpu_syscore_ops);
136 register_cpu_notifier(&ledtrig_cpu_nb);
137
138 pr_info("ledtrig-cpu: registered to indicate activity on CPUs\n");
139
140 return 0;
141}
142device_initcall(ledtrig_cpu_init);
143