arch/arm/mach-shark/leds.c

   1 /*
   2  * arch/arm/kernel/leds-shark.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/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 DEFINE_SPINLOCK(leds_lock);
  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);