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
  35 static void pmu_req_done(struct adb_request * req)
  36 {
  37         unsigned long flags;
  38
  39         spin_lock_irqsave(&pmu_blink_lock, flags);
  40         /* if someone requested a change in the meantime
  41          * (we only see the last one which is fine)
  42          * then apply it now */
  43         if (requested_change != -1 && !pmu_sys_suspended)
  44                 pmu_request(&pmu_blink_req, NULL, 4, 0xee, 4, 0, requested_change);
  45         /* reset requested change */
  46         requested_change = -1;
  47         spin_unlock_irqrestore(&pmu_blink_lock, flags);
  48 }
  49
  50 static void pmu_led_set(struct led_classdev *led_cdev,
  51                         enum led_brightness brightness)
  52 {
  53         unsigned long flags;
  54
  55         spin_lock_irqsave(&pmu_blink_lock, flags);
  56         switch (brightness) {
  57         case LED_OFF:
  58                 requested_change = 0;
  59                 break;
  60         case LED_FULL:
  61                 requested_change = 1;
  62                 break;
  63         default:
  64                 goto out;
  65                 break;
  66         }
  67         /* if request isn't done, then don't do anything */
  68         if (pmu_blink_req.complete && !pmu_sys_suspended)
  69                 pmu_request(&pmu_blink_req, NULL, 4, 0xee, 4, 0, requested_change);
  70  out:
  71         spin_unlock_irqrestore(&pmu_blink_lock, flags);
  72 }
  73
  74 static struct led_classdev pmu_led = {
  75         .name = "pmu-led::front",
  76 #ifdef CONFIG_ADB_PMU_LED_DISK
  77         .default_trigger = "disk-activity",
  78 #endif
  79         .brightness_set = pmu_led_set,
  80 };
  81
  82 static int __init via_pmu_led_init(void)
  83 {
  84         struct device_node *dt;
  85         const char *model;
  86
  87         /* only do this on keylargo based models */
  88         if (pmu_get_model() != PMU_KEYLARGO_BASED)
  89                 return -ENODEV;
  90
  91         dt = of_find_node_by_path("/");
  92         if (dt == NULL)
  93                 return -ENODEV;
  94         model = of_get_property(dt, "model", NULL);
  95         if (model == NULL) {
  96                 of_node_put(dt);
  97                 return -ENODEV;
  98         }
  99         if (strncmp(model, "PowerBook", strlen("PowerBook")) != 0 &&
 100             strncmp(model, "iBook", strlen("iBook")) != 0 &&
 101             strcmp(model, "PowerMac7,2") != 0 &&
 102             strcmp(model, "PowerMac7,3") != 0) {
 103                 of_node_put(dt);
 104                 /* ignore */
 105                 return -ENODEV;
 106         }
 107         of_node_put(dt);
 108
 109         spin_lock_init(&pmu_blink_lock);
 110         /* no outstanding req */
 111         pmu_blink_req.complete = 1;
 112         pmu_blink_req.done = pmu_req_done;
 113
 114         return led_classdev_register(NULL, &pmu_led);
 115 }
 116
 117 late_initcall(via_pmu_led_init);