drivers/macintosh/via-pmu-led.c

   1 /*
   2  * via-pmu LED class device
   3  *
   4  * Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
   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 as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  14  * NON INFRINGEMENT.  See the GNU General Public License for more
  15  * details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  20  *
  21  */
  22 #include <linux/types.h>
  23 #include <linux/kernel.h>
  24 #include <linux/device.h>
  25 #include <linux/leds.h>
  26 #include <linux/adb.h>
  27 #include <linux/pmu.h>
  28 #include <asm/prom.h>
  29
  30 static spinlock_t pmu_blink_lock;
  31 static struct adb_request pmu_blink_req;
  32 /* -1: no change, 0: request off, 1: request on */
  33 static int requested_change;
  34 static int sleeping;
  35
  36 static void pmu_req_done(struct adb_request * req)
  37 {
  38         unsigned long flags;
  39
  40         spin_lock_irqsave(&pmu_blink_lock, flags);
  41         /* if someone requested a change in the meantime
  42          * (we only see the last one which is fine)
  43          * then apply it now */
  44         if (requested_change != -1 && !sleeping)
  45                 pmu_request(&pmu_blink_req, NULL, 4, 0xee, 4, 0, requested_change);
  46         /* reset requested change */
  47         requested_change = -1;
  48         spin_unlock_irqrestore(&pmu_blink_lock, flags);
  49 }
  50
  51 static void pmu_led_set(struct led_classdev *led_cdev,
  52                         enum led_brightness brightness)
  53 {
  54         unsigned long flags;
  55
  56         spin_lock_irqsave(&pmu_blink_lock, flags);
  57         switch (brightness) {
  58         case LED_OFF:
  59                 requested_change = 0;
  60                 break;
  61         case LED_FULL:
  62                 requested_change = 1;
  63                 break;
  64         default:
  65                 goto out;
  66                 break;
  67         }
  68         /* if request isn't done, then don't do anything */
  69         if (pmu_blink_req.complete && !sleeping)
  70                 pmu_request(&pmu_blink_req, NULL, 4, 0xee, 4, 0, requested_change);
  71  out:
  72         spin_unlock_irqrestore(&pmu_blink_lock, flags);
  73 }
  74
  75 static struct led_classdev pmu_led = {
  76         .name = "pmu-front-led",
  77 #ifdef CONFIG_ADB_PMU_LED_IDE
  78         .default_trigger = "ide-disk",
  79 #endif
  80         .brightness_set = pmu_led_set,
  81 };
  82
  83 #ifdef CONFIG_PM
  84 static int pmu_led_sleep_call(struct pmu_sleep_notifier *self, int when)
  85 {
  86         unsigned long flags;
  87
  88         spin_lock_irqsave(&pmu_blink_lock, flags);
  89
  90         switch (when) {
  91         case PBOOK_SLEEP_REQUEST:
  92                 sleeping = 1;
  93                 break;
  94         case PBOOK_WAKE:
  95                 sleeping = 0;
  96                 break;
  97         default:
  98                 /* do nothing */
  99                 break;
 100         }
 101         spin_unlock_irqrestore(&pmu_blink_lock, flags);
 102
 103         return PBOOK_SLEEP_OK;
 104 }
 105
 106 static struct pmu_sleep_notifier via_pmu_led_sleep_notif = {
 107         .notifier_call = pmu_led_sleep_call,
 108 };
 109 #endif
 110
 111 static int __init via_pmu_led_init(void)
 112 {
 113         struct device_node *dt;
 114         const char *model;
 115
 116         /* only do this on keylargo based models */
 117         if (pmu_get_model() != PMU_KEYLARGO_BASED)
 118                 return -ENODEV;
 119
 120         dt = of_find_node_by_path("/");
 121         if (dt == NULL)
 122                 return -ENODEV;
 123         model = get_property(dt, "model", NULL);
 124         if (model == NULL)
 125                 return -ENODEV;
 126         if (strncmp(model, "PowerBook", strlen("PowerBook")) != 0 &&
 127             strncmp(model, "iBook", strlen("iBook")) != 0) {
 128                 of_node_put(dt);
 129                 /* ignore */
 130                 return -ENODEV;
 131         }
 132         of_node_put(dt);
 133
 134         spin_lock_init(&pmu_blink_lock);
 135         /* no outstanding req */
 136         pmu_blink_req.complete = 1;
 137         pmu_blink_req.done = pmu_req_done;
 138 #ifdef CONFIG_PM
 139         pmu_register_sleep_notifier(&via_pmu_led_sleep_notif);
 140 #endif
 141         return led_classdev_register(NULL, &pmu_led);
 142 }
 143
 144 late_initcall(via_pmu_led_init);