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401e9093 PM |
1 | /* |
2 | * Generic heartbeat driver for regular LED banks | |
3 | * | |
10ab92d8 | 4 | * Copyright (C) 2007 - 2010 Paul Mundt |
401e9093 PM |
5 | * |
6 | * Most SH reference boards include a number of individual LEDs that can | |
7 | * be independently controlled (either via a pre-defined hardware | |
8 | * function or via the LED class, if desired -- the hardware tends to | |
9 | * encapsulate some of the same "triggers" that the LED class supports, | |
10 | * so there's not too much value in it). | |
11 | * | |
12 | * Additionally, most of these boards also have a LED bank that we've | |
13 | * traditionally used for strobing the load average. This use case is | |
14 | * handled by this driver, rather than giving each LED bit position its | |
15 | * own struct device. | |
16 | * | |
17 | * This file is subject to the terms and conditions of the GNU General Public | |
18 | * License. See the file "COPYING" in the main directory of this archive | |
19 | * for more details. | |
20 | */ | |
21 | #include <linux/init.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/platform_device.h> | |
24 | #include <linux/sched.h> | |
25 | #include <linux/timer.h> | |
26 | #include <linux/io.h> | |
5a0e3ad6 | 27 | #include <linux/slab.h> |
8786c952 | 28 | #include <asm/heartbeat.h> |
401e9093 PM |
29 | |
30 | #define DRV_NAME "heartbeat" | |
10ab92d8 | 31 | #define DRV_VERSION "0.1.2" |
401e9093 | 32 | |
8786c952 PM |
33 | static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 }; |
34 | ||
35 | static inline void heartbeat_toggle_bit(struct heartbeat_data *hd, | |
36 | unsigned bit, unsigned int inverted) | |
37 | { | |
38 | unsigned int new; | |
39 | ||
40 | new = (1 << hd->bit_pos[bit]); | |
41 | if (inverted) | |
42 | new = ~new; | |
43 | ||
e174d130 KM |
44 | new &= hd->mask; |
45 | ||
8786c952 PM |
46 | switch (hd->regsize) { |
47 | case 32: | |
e174d130 | 48 | new |= ioread32(hd->base) & ~hd->mask; |
8786c952 PM |
49 | iowrite32(new, hd->base); |
50 | break; | |
51 | case 16: | |
e174d130 | 52 | new |= ioread16(hd->base) & ~hd->mask; |
8786c952 PM |
53 | iowrite16(new, hd->base); |
54 | break; | |
55 | default: | |
e174d130 | 56 | new |= ioread8(hd->base) & ~hd->mask; |
8786c952 PM |
57 | iowrite8(new, hd->base); |
58 | break; | |
59 | } | |
60 | } | |
401e9093 PM |
61 | |
62 | static void heartbeat_timer(unsigned long data) | |
63 | { | |
64 | struct heartbeat_data *hd = (struct heartbeat_data *)data; | |
65 | static unsigned bit = 0, up = 1; | |
66 | ||
8786c952 PM |
67 | heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED); |
68 | ||
f6072896 | 69 | bit += up; |
8786c952 | 70 | if ((bit == 0) || (bit == (hd->nr_bits)-1)) |
f6072896 | 71 | up = -up; |
401e9093 PM |
72 | |
73 | mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) / | |
74 | ((avenrun[0] / 5) + (3 << FSHIFT))))); | |
75 | } | |
76 | ||
77 | static int heartbeat_drv_probe(struct platform_device *pdev) | |
78 | { | |
79 | struct resource *res; | |
80 | struct heartbeat_data *hd; | |
e174d130 | 81 | int i; |
401e9093 PM |
82 | |
83 | if (unlikely(pdev->num_resources != 1)) { | |
84 | dev_err(&pdev->dev, "invalid number of resources\n"); | |
85 | return -EINVAL; | |
86 | } | |
87 | ||
88 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
89 | if (unlikely(res == NULL)) { | |
90 | dev_err(&pdev->dev, "invalid resource\n"); | |
91 | return -EINVAL; | |
92 | } | |
93 | ||
401e9093 | 94 | if (pdev->dev.platform_data) { |
8786c952 | 95 | hd = pdev->dev.platform_data; |
401e9093 | 96 | } else { |
8786c952 PM |
97 | hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL); |
98 | if (unlikely(!hd)) | |
99 | return -ENOMEM; | |
100 | } | |
101 | ||
10ab92d8 | 102 | hd->base = ioremap_nocache(res->start, resource_size(res)); |
1de83e94 | 103 | if (unlikely(!hd->base)) { |
8786c952 PM |
104 | dev_err(&pdev->dev, "ioremap failed\n"); |
105 | ||
106 | if (!pdev->dev.platform_data) | |
107 | kfree(hd); | |
108 | ||
109 | return -ENXIO; | |
110 | } | |
401e9093 | 111 | |
8786c952 PM |
112 | if (!hd->nr_bits) { |
113 | hd->bit_pos = default_bit_pos; | |
114 | hd->nr_bits = ARRAY_SIZE(default_bit_pos); | |
401e9093 PM |
115 | } |
116 | ||
e174d130 KM |
117 | hd->mask = 0; |
118 | for (i = 0; i < hd->nr_bits; i++) | |
119 | hd->mask |= (1 << hd->bit_pos[i]); | |
120 | ||
10ab92d8 PM |
121 | if (!hd->regsize) { |
122 | switch (res->flags & IORESOURCE_MEM_TYPE_MASK) { | |
123 | case IORESOURCE_MEM_32BIT: | |
124 | hd->regsize = 32; | |
125 | break; | |
126 | case IORESOURCE_MEM_16BIT: | |
127 | hd->regsize = 16; | |
128 | break; | |
129 | case IORESOURCE_MEM_8BIT: | |
130 | default: | |
131 | hd->regsize = 8; | |
132 | break; | |
133 | } | |
134 | } | |
401e9093 PM |
135 | |
136 | setup_timer(&hd->timer, heartbeat_timer, (unsigned long)hd); | |
137 | platform_set_drvdata(pdev, hd); | |
138 | ||
139 | return mod_timer(&hd->timer, jiffies + 1); | |
140 | } | |
141 | ||
142 | static int heartbeat_drv_remove(struct platform_device *pdev) | |
143 | { | |
144 | struct heartbeat_data *hd = platform_get_drvdata(pdev); | |
145 | ||
146 | del_timer_sync(&hd->timer); | |
8786c952 | 147 | iounmap(hd->base); |
401e9093 PM |
148 | |
149 | platform_set_drvdata(pdev, NULL); | |
150 | ||
8786c952 PM |
151 | if (!pdev->dev.platform_data) |
152 | kfree(hd); | |
401e9093 PM |
153 | |
154 | return 0; | |
155 | } | |
156 | ||
157 | static struct platform_driver heartbeat_driver = { | |
158 | .probe = heartbeat_drv_probe, | |
159 | .remove = heartbeat_drv_remove, | |
160 | .driver = { | |
161 | .name = DRV_NAME, | |
162 | }, | |
163 | }; | |
164 | ||
165 | static int __init heartbeat_init(void) | |
166 | { | |
167 | printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION); | |
168 | return platform_driver_register(&heartbeat_driver); | |
169 | } | |
170 | ||
171 | static void __exit heartbeat_exit(void) | |
172 | { | |
173 | platform_driver_unregister(&heartbeat_driver); | |
174 | } | |
175 | module_init(heartbeat_init); | |
176 | module_exit(heartbeat_exit); | |
177 | ||
178 | MODULE_VERSION(DRV_VERSION); | |
179 | MODULE_AUTHOR("Paul Mundt"); | |
839cd310 | 180 | MODULE_LICENSE("GPL v2"); |