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);
118