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1/*
2 * Generic heartbeat driver for regular LED banks
3 *
4 * Copyright (C) 2007 - 2010 Paul Mundt
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>
27#include <linux/slab.h>
28#include <asm/heartbeat.h>
29
30#define DRV_NAME "heartbeat"
31#define DRV_VERSION "0.1.2"
32
33static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
34
35static 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
44 new &= hd->mask;
45
46 switch (hd->regsize) {
47 case 32:
48 new |= ioread32(hd->base) & ~hd->mask;
49 iowrite32(new, hd->base);
50 break;
51 case 16:
52 new |= ioread16(hd->base) & ~hd->mask;
53 iowrite16(new, hd->base);
54 break;
55 default:
56 new |= ioread8(hd->base) & ~hd->mask;
57 iowrite8(new, hd->base);
58 break;
59 }
60}
61
62static void heartbeat_timer(unsigned long data)
63{
64 struct heartbeat_data *hd = (struct heartbeat_data *)data;
65 static unsigned bit = 0, up = 1;
66
67 heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
68
69 bit += up;
70 if ((bit == 0) || (bit == (hd->nr_bits)-1))
71 up = -up;
72
73 mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
74 ((avenrun[0] / 5) + (3 << FSHIFT)))));
75}
76
77static int heartbeat_drv_probe(struct platform_device *pdev)
78{
79 struct resource *res;
80 struct heartbeat_data *hd;
81 int i;
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
94 if (pdev->dev.platform_data) {
95 hd = pdev->dev.platform_data;
96 } else {
97 hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
98 if (unlikely(!hd))
99 return -ENOMEM;
100 }
101
102 hd->base = ioremap_nocache(res->start, resource_size(res));
103 if (unlikely(!hd->base)) {
104 dev_err(&pdev->dev, "ioremap failed\n");
105
106 if (!pdev->dev.platform_data)
107 kfree(hd);
108
109 return -ENXIO;
110 }
111
112 if (!hd->nr_bits) {
113 hd->bit_pos = default_bit_pos;
114 hd->nr_bits = ARRAY_SIZE(default_bit_pos);
115 }
116
117 hd->mask = 0;
118 for (i = 0; i < hd->nr_bits; i++)
119 hd->mask |= (1 << hd->bit_pos[i]);
120
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 }
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
142static 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);
147 iounmap(hd->base);
148
149 platform_set_drvdata(pdev, NULL);
150
151 if (!pdev->dev.platform_data)
152 kfree(hd);
153
154 return 0;
155}
156
157static struct platform_driver heartbeat_driver = {
158 .probe = heartbeat_drv_probe,
159 .remove = heartbeat_drv_remove,
160 .driver = {
161 .name = DRV_NAME,
162 },
163};
164
165static 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
171static void __exit heartbeat_exit(void)
172{
173 platform_driver_unregister(&heartbeat_driver);
174}
175module_init(heartbeat_init);
176module_exit(heartbeat_exit);
177
178MODULE_VERSION(DRV_VERSION);
179MODULE_AUTHOR("Paul Mundt");
180MODULE_LICENSE("GPL v2");
1/*
2 * Generic heartbeat driver for regular LED banks
3 *
4 * Copyright (C) 2007 - 2010 Paul Mundt
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>
27#include <linux/slab.h>
28#include <asm/heartbeat.h>
29
30#define DRV_NAME "heartbeat"
31#define DRV_VERSION "0.1.2"
32
33static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
34
35static 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
44 new &= hd->mask;
45
46 switch (hd->regsize) {
47 case 32:
48 new |= ioread32(hd->base) & ~hd->mask;
49 iowrite32(new, hd->base);
50 break;
51 case 16:
52 new |= ioread16(hd->base) & ~hd->mask;
53 iowrite16(new, hd->base);
54 break;
55 default:
56 new |= ioread8(hd->base) & ~hd->mask;
57 iowrite8(new, hd->base);
58 break;
59 }
60}
61
62static void heartbeat_timer(unsigned long data)
63{
64 struct heartbeat_data *hd = (struct heartbeat_data *)data;
65 static unsigned bit = 0, up = 1;
66
67 heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED);
68
69 bit += up;
70 if ((bit == 0) || (bit == (hd->nr_bits)-1))
71 up = -up;
72
73 mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) /
74 ((avenrun[0] / 5) + (3 << FSHIFT)))));
75}
76
77static int heartbeat_drv_probe(struct platform_device *pdev)
78{
79 struct resource *res;
80 struct heartbeat_data *hd;
81 int i;
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
94 if (pdev->dev.platform_data) {
95 hd = pdev->dev.platform_data;
96 } else {
97 hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL);
98 if (unlikely(!hd))
99 return -ENOMEM;
100 }
101
102 hd->base = ioremap_nocache(res->start, resource_size(res));
103 if (unlikely(!hd->base)) {
104 dev_err(&pdev->dev, "ioremap failed\n");
105
106 if (!pdev->dev.platform_data)
107 kfree(hd);
108
109 return -ENXIO;
110 }
111
112 if (!hd->nr_bits) {
113 hd->bit_pos = default_bit_pos;
114 hd->nr_bits = ARRAY_SIZE(default_bit_pos);
115 }
116
117 hd->mask = 0;
118 for (i = 0; i < hd->nr_bits; i++)
119 hd->mask |= (1 << hd->bit_pos[i]);
120
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 }
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
142static 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);
147 iounmap(hd->base);
148
149 platform_set_drvdata(pdev, NULL);
150
151 if (!pdev->dev.platform_data)
152 kfree(hd);
153
154 return 0;
155}
156
157static struct platform_driver heartbeat_driver = {
158 .probe = heartbeat_drv_probe,
159 .remove = heartbeat_drv_remove,
160 .driver = {
161 .name = DRV_NAME,
162 },
163};
164
165static 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
171static void __exit heartbeat_exit(void)
172{
173 platform_driver_unregister(&heartbeat_driver);
174}
175module_init(heartbeat_init);
176module_exit(heartbeat_exit);
177
178MODULE_VERSION(DRV_VERSION);
179MODULE_AUTHOR("Paul Mundt");
180MODULE_LICENSE("GPL v2");