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