File: /usr/src/linux/arch/arm/mach-shark/leds.c
1 /*
2 * arch/arm/kernel/leds-shark.c
3 * by Alexander Schulz <aschulz@netwinder.org>
4 *
5 * derived from:
6 * arch/arm/kernel/leds-footbridge.c
7 * Copyright (C) 1998-1999 Russell King
8 *
9 * DIGITAL Shark LED control routines.
10 *
11 * The leds use is as follows:
12 * - Green front - toggles state every 50 timer interrupts
13 * - Amber front - Unused, this is a dual color led (Amber/Green)
14 * - Amber back - On if system is not idle
15 *
16 * Changelog:
17 */
18 #include <linux/config.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/spinlock.h>
23 #include <linux/ioport.h>
24
25 #include <asm/hardware.h>
26 #include <asm/leds.h>
27 #include <asm/io.h>
28 #include <asm/system.h>
29
30 #define LED_STATE_ENABLED 1
31 #define LED_STATE_CLAIMED 2
32 static char led_state;
33 static short hw_led_state;
34 static short saved_state;
35
36 static spinlock_t leds_lock = SPIN_LOCK_UNLOCKED;
37
38 short sequoia_read(int addr) {
39 outw(addr,0x24);
40 return inw(0x26);
41 }
42
43 void sequoia_write(short value,short addr) {
44 outw(addr,0x24);
45 outw(value,0x26);
46 }
47
48 static void sequoia_leds_event(led_event_t evt)
49 {
50 unsigned long flags;
51
52 spin_lock_irqsave(&leds_lock, flags);
53
54 hw_led_state = sequoia_read(0x09);
55
56 switch (evt) {
57 case led_start:
58 hw_led_state |= SEQUOIA_LED_GREEN;
59 hw_led_state |= SEQUOIA_LED_AMBER;
60 #ifdef CONFIG_LEDS_CPU
61 hw_led_state |= SEQUOIA_LED_BACK;
62 #else
63 hw_led_state &= ~SEQUOIA_LED_BACK;
64 #endif
65 led_state |= LED_STATE_ENABLED;
66 break;
67
68 case led_stop:
69 hw_led_state &= ~SEQUOIA_LED_BACK;
70 hw_led_state |= SEQUOIA_LED_GREEN;
71 hw_led_state |= SEQUOIA_LED_AMBER;
72 led_state &= ~LED_STATE_ENABLED;
73 break;
74
75 case led_claim:
76 led_state |= LED_STATE_CLAIMED;
77 saved_state = hw_led_state;
78 hw_led_state &= ~SEQUOIA_LED_BACK;
79 hw_led_state |= SEQUOIA_LED_GREEN;
80 hw_led_state |= SEQUOIA_LED_AMBER;
81 break;
82
83 case led_release:
84 led_state &= ~LED_STATE_CLAIMED;
85 hw_led_state = saved_state;
86 break;
87
88 #ifdef CONFIG_LEDS_TIMER
89 case led_timer:
90 if (!(led_state & LED_STATE_CLAIMED))
91 hw_led_state ^= SEQUOIA_LED_GREEN;
92 break;
93 #endif
94
95 #ifdef CONFIG_LEDS_CPU
96 case led_idle_start:
97 if (!(led_state & LED_STATE_CLAIMED))
98 hw_led_state &= ~SEQUOIA_LED_BACK;
99 break;
100
101 case led_idle_end:
102 if (!(led_state & LED_STATE_CLAIMED))
103 hw_led_state |= SEQUOIA_LED_BACK;
104 break;
105 #endif
106
107 case led_green_on:
108 if (led_state & LED_STATE_CLAIMED)
109 hw_led_state &= ~SEQUOIA_LED_GREEN;
110 break;
111
112 case led_green_off:
113 if (led_state & LED_STATE_CLAIMED)
114 hw_led_state |= SEQUOIA_LED_GREEN;
115 break;
116
117 case led_amber_on:
118 if (led_state & LED_STATE_CLAIMED)
119 hw_led_state &= ~SEQUOIA_LED_AMBER;
120 break;
121
122 case led_amber_off:
123 if (led_state & LED_STATE_CLAIMED)
124 hw_led_state |= SEQUOIA_LED_AMBER;
125 break;
126
127 case led_red_on:
128 if (led_state & LED_STATE_CLAIMED)
129 hw_led_state |= SEQUOIA_LED_BACK;
130 break;
131
132 case led_red_off:
133 if (led_state & LED_STATE_CLAIMED)
134 hw_led_state &= ~SEQUOIA_LED_BACK;
135 break;
136
137 default:
138 break;
139 }
140
141 if (led_state & LED_STATE_ENABLED)
142 sequoia_write(hw_led_state,0x09);
143
144 spin_unlock_irqrestore(&leds_lock, flags);
145 }
146
147 static int __init leds_init(void)
148 {
149 extern void (*leds_event)(led_event_t);
150 short temp;
151
152 leds_event = sequoia_leds_event;
153
154 /* Make LEDs independent of power-state */
155 request_region(0x24,4,"sequoia");
156 temp = sequoia_read(0x09);
157 temp |= 1<<10;
158 sequoia_write(temp,0x09);
159 leds_event(led_start);
160 return 0;
161 }
162
163 __initcall(leds_init);
164