arch/arm/mach-shark/leds.c

   1 /*
   2  * arch/arm/mach-shark/leds.c
   3  * by Alexander Schulz
   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/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/ioport.h>
  23 #include <linux/io.h>
  24
  25 #include <asm/leds.h>
  26 #include <asm/system.h>
  27
  28 #define LED_STATE_ENABLED       1
  29 #define LED_STATE_CLAIMED       2
  30
  31 #define SEQUOIA_LED_GREEN       (1<<6)
  32 #define SEQUOIA_LED_AMBER       (1<<5)
  33 #define SEQUOIA_LED_BACK        (1<<7)
  34
  35 static char led_state;
  36 static short hw_led_state;
  37 static short saved_state;
  38
  39 static DEFINE_SPINLOCK(leds_lock);
  40
  41 short sequoia_read(int addr) {
  42   outw(addr,0x24);
  43   return inw(0x26);
  44 }
  45
  46 void sequoia_write(short value,short addr) {
  47   outw(addr,0x24);
  48   outw(value,0x26);
  49 }
  50
  51 static void sequoia_leds_event(led_event_t evt)
  52 {
  53         unsigned long flags;
  54
  55         spin_lock_irqsave(&leds_lock, flags);
  56
  57         hw_led_state = sequoia_read(0x09);
  58
  59         switch (evt) {
  60         case led_start:
  61                 hw_led_state |= SEQUOIA_LED_GREEN;
  62                 hw_led_state |= SEQUOIA_LED_AMBER;
  63 #ifdef CONFIG_LEDS_CPU
  64                 hw_led_state |= SEQUOIA_LED_BACK;
  65 #else
  66                 hw_led_state &= ~SEQUOIA_LED_BACK;
  67 #endif
  68                 led_state |= LED_STATE_ENABLED;
  69                 break;
  70
  71         case led_stop:
  72                 hw_led_state &= ~SEQUOIA_LED_BACK;
  73                 hw_led_state |= SEQUOIA_LED_GREEN;
  74                 hw_led_state |= SEQUOIA_LED_AMBER;
  75                 led_state &= ~LED_STATE_ENABLED;
  76                 break;
  77
  78         case led_claim:
  79                 led_state |= LED_STATE_CLAIMED;
  80                 saved_state = hw_led_state;
  81                 hw_led_state &= ~SEQUOIA_LED_BACK;
  82                 hw_led_state |= SEQUOIA_LED_GREEN;
  83                 hw_led_state |= SEQUOIA_LED_AMBER;
  84                 break;
  85
  86         case led_release:
  87                 led_state &= ~LED_STATE_CLAIMED;
  88                 hw_led_state = saved_state;
  89                 break;
  90
  91 #ifdef CONFIG_LEDS_TIMER
  92         case led_timer:
  93                 if (!(led_state & LED_STATE_CLAIMED))
  94                         hw_led_state ^= SEQUOIA_LED_GREEN;
  95                 break;
  96 #endif
  97
  98 #ifdef CONFIG_LEDS_CPU
  99         case led_idle_start:
 100                 if (!(led_state & LED_STATE_CLAIMED))
 101                         hw_led_state &= ~SEQUOIA_LED_BACK;
 102                 break;
 103
 104         case led_idle_end:
 105                 if (!(led_state & LED_STATE_CLAIMED))
 106                         hw_led_state |= SEQUOIA_LED_BACK;
 107                 break;
 108 #endif
 109
 110         case led_green_on:
 111                 if (led_state & LED_STATE_CLAIMED)
 112                         hw_led_state &= ~SEQUOIA_LED_GREEN;
 113                 break;
 114
 115         case led_green_off:
 116                 if (led_state & LED_STATE_CLAIMED)
 117                         hw_led_state |= SEQUOIA_LED_GREEN;
 118                 break;
 119
 120         case led_amber_on:
 121                 if (led_state & LED_STATE_CLAIMED)
 122                         hw_led_state &= ~SEQUOIA_LED_AMBER;
 123                 break;
 124
 125         case led_amber_off:
 126                 if (led_state & LED_STATE_CLAIMED)
 127                         hw_led_state |= SEQUOIA_LED_AMBER;
 128                 break;
 129
 130         case led_red_on:
 131                 if (led_state & LED_STATE_CLAIMED)
 132                         hw_led_state |= SEQUOIA_LED_BACK;
 133                 break;
 134
 135         case led_red_off:
 136                 if (led_state & LED_STATE_CLAIMED)
 137                         hw_led_state &= ~SEQUOIA_LED_BACK;
 138                 break;
 139
 140         default:
 141                 break;
 142         }
 143
 144         if  (led_state & LED_STATE_ENABLED)
 145                 sequoia_write(hw_led_state,0x09);
 146
 147         spin_unlock_irqrestore(&leds_lock, flags);
 148 }
 149
 150 static int __init leds_init(void)
 151 {
 152         extern void (*leds_event)(led_event_t);
 153         short temp;
 154
 155         leds_event = sequoia_leds_event;
 156
 157         /* Make LEDs independent of power-state */
 158         request_region(0x24,4,"sequoia");
 159         temp = sequoia_read(0x09);
 160         temp |= 1<<10;
 161         sequoia_write(temp,0x09);
 162         leds_event(led_start);
 163         return 0;
 164 }
 165
 166 __initcall(leds_init);