xref: /openbmc/linux/drivers/macintosh/via-pmu-led.c (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
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 <linux/of.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  
pmu_req_done(struct adb_request * req)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  
pmu_led_set(struct led_classdev * led_cdev,enum led_brightness brightness)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  
via_pmu_led_init(void)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);
118