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