kernel/linux/arch/arm/mach-footbridge/netwinder-leds.c

   1 /*
   2  *  linux/arch/arm/mach-footbridge/netwinder-leds.c
   3  *
   4  *  Copyright (C) 1998-1999 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * NetWinder LED control routines.
  11  *
  12  * The Netwinder uses the leds as follows:
  13  *  - Green - toggles state every 50 timer interrupts
  14  *  - Red   - On if the system is not idle
  15  *
  16  * Changelog:
  17  *   02-05-1999 RMK     Various cleanups
  18  */
  19 #include <linux/config.h>
  20 #include <linux/module.h>
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/spinlock.h>
  24
  25 #include <asm/hardware.h>
  26 #include <asm/leds.h>
  27 #include <asm/mach-types.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 char hw_led_state;
  34
  35 static spinlock_t leds_lock = SPIN_LOCK_UNLOCKED;
  36 extern spinlock_t gpio_lock;
  37
  38 static void netwinder_leds_event(led_event_t evt)
  39 {
  40         unsigned long flags;
  41
  42         spin_lock_irqsave(&leds_lock, flags);
  43
  44         switch (evt) {
  45         case led_start:
  46                 led_state |= LED_STATE_ENABLED;
  47                 hw_led_state = GPIO_GREEN_LED;
  48                 break;
  49
  50         case led_stop:
  51                 led_state &= ~LED_STATE_ENABLED;
  52                 break;
  53
  54         case led_claim:
  55                 led_state |= LED_STATE_CLAIMED;
  56                 hw_led_state = 0;
  57                 break;
  58
  59         case led_release:
  60                 led_state &= ~LED_STATE_CLAIMED;
  61                 hw_led_state = 0;
  62                 break;
  63
  64 #ifdef CONFIG_LEDS_TIMER
  65         case led_timer:
  66                 if (!(led_state & LED_STATE_CLAIMED))
  67                         hw_led_state ^= GPIO_GREEN_LED;
  68                 break;
  69 #endif
  70
  71 #ifdef CONFIG_LEDS_CPU
  72         case led_idle_start:
  73                 if (!(led_state & LED_STATE_CLAIMED))
  74                         hw_led_state &= ~GPIO_RED_LED;
  75                 break;
  76
  77         case led_idle_end:
  78                 if (!(led_state & LED_STATE_CLAIMED))
  79                         hw_led_state |= GPIO_RED_LED;
  80                 break;
  81 #endif
  82
  83         case led_halted:
  84                 if (!(led_state & LED_STATE_CLAIMED))
  85                         hw_led_state |= GPIO_RED_LED;
  86                 break;
  87
  88         case led_green_on:
  89                 if (led_state & LED_STATE_CLAIMED)
  90                         hw_led_state |= GPIO_GREEN_LED;
  91                 break;
  92
  93         case led_green_off:
  94                 if (led_state & LED_STATE_CLAIMED)
  95                         hw_led_state &= ~GPIO_GREEN_LED;
  96                 break;
  97
  98         case led_amber_on:
  99                 if (led_state & LED_STATE_CLAIMED)
 100                         hw_led_state |= GPIO_GREEN_LED | GPIO_RED_LED;
 101                 break;
 102
 103         case led_amber_off:
 104                 if (led_state & LED_STATE_CLAIMED)
 105                         hw_led_state &= ~(GPIO_GREEN_LED | GPIO_RED_LED);
 106                 break;
 107
 108         case led_red_on:
 109                 if (led_state & LED_STATE_CLAIMED)
 110                         hw_led_state |= GPIO_RED_LED;
 111                 break;
 112
 113         case led_red_off:
 114                 if (led_state & LED_STATE_CLAIMED)
 115                         hw_led_state &= ~GPIO_RED_LED;
 116                 break;
 117
 118         default:
 119                 break;
 120         }
 121
 122         spin_unlock_irqrestore(&leds_lock, flags);
 123
 124         if  (led_state & LED_STATE_ENABLED) {
 125                 spin_lock_irqsave(&gpio_lock, flags);
 126                 gpio_modify_op(GPIO_RED_LED | GPIO_GREEN_LED, hw_led_state);
 127                 spin_unlock_irqrestore(&gpio_lock, flags);
 128         }
 129 }
 130
 131 static int __init leds_init(void)
 132 {
 133         if (machine_is_netwinder())
 134                 leds_event = netwinder_leds_event;
 135
 136         leds_event(led_start);
 137
 138         return 0;
 139 }
 140
 141 __initcall(leds_init);