Commit | Line | Data |
---|---|---|
1ca5df0a JC |
1 | /* linux/drivers/char/nsc_gpio.c |
2 | ||
3 | National Semiconductor common GPIO device-file/VFS methods. | |
4 | Allows a user space process to control the GPIO pins. | |
5 | ||
6 | Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> | |
7 | Copyright (c) 2005 Jim Cromie <jim.cromie@gmail.com> | |
8 | */ | |
9 | ||
1ca5df0a JC |
10 | #include <linux/fs.h> |
11 | #include <linux/module.h> | |
12 | #include <linux/errno.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/init.h> | |
15 | #include <linux/nsc_gpio.h> | |
f31000e5 | 16 | #include <linux/platform_device.h> |
1ca5df0a JC |
17 | #include <asm/uaccess.h> |
18 | #include <asm/io.h> | |
19 | ||
20 | #define NAME "nsc_gpio" | |
21 | ||
f31000e5 | 22 | void nsc_gpio_dump(struct nsc_gpio_ops *amp, unsigned index) |
0e41ef3c | 23 | { |
f31000e5 JC |
24 | /* retrieve current config w/o changing it */ |
25 | u32 config = amp->gpio_config(index, ~0, 0); | |
26 | ||
27 | /* user requested via 'v' command, so its INFO */ | |
23916a8e | 28 | dev_info(amp->dev, "io%02u: 0x%04x %s %s %s %s %s %s %s\tio:%d/%d\n", |
f31000e5 JC |
29 | index, config, |
30 | (config & 1) ? "OE" : "TS", /* output-enabled/tristate */ | |
31 | (config & 2) ? "PP" : "OD", /* push pull / open drain */ | |
32 | (config & 4) ? "PUE" : "PUD", /* pull up enabled/disabled */ | |
33 | (config & 8) ? "LOCKED" : "", /* locked / unlocked */ | |
34 | (config & 16) ? "LEVEL" : "EDGE",/* level/edge input */ | |
35 | (config & 32) ? "HI" : "LO", /* trigger on rise/fall edge */ | |
23916a8e JC |
36 | (config & 64) ? "DEBOUNCE" : "", /* debounce */ |
37 | ||
38 | amp->gpio_get(index), amp->gpio_current(index)); | |
0e41ef3c JC |
39 | } |
40 | ||
1a66fdf0 JC |
41 | ssize_t nsc_gpio_write(struct file *file, const char __user *data, |
42 | size_t len, loff_t *ppos) | |
43 | { | |
496ad9aa | 44 | unsigned m = iminor(file_inode(file)); |
1a66fdf0 | 45 | struct nsc_gpio_ops *amp = file->private_data; |
f31000e5 | 46 | struct device *dev = amp->dev; |
1a66fdf0 JC |
47 | size_t i; |
48 | int err = 0; | |
49 | ||
50 | for (i = 0; i < len; ++i) { | |
51 | char c; | |
52 | if (get_user(c, data + i)) | |
53 | return -EFAULT; | |
54 | switch (c) { | |
55 | case '0': | |
56 | amp->gpio_set(m, 0); | |
57 | break; | |
58 | case '1': | |
59 | amp->gpio_set(m, 1); | |
60 | break; | |
61 | case 'O': | |
f31000e5 | 62 | dev_dbg(dev, "GPIO%d output enabled\n", m); |
1a66fdf0 JC |
63 | amp->gpio_config(m, ~1, 1); |
64 | break; | |
65 | case 'o': | |
f31000e5 | 66 | dev_dbg(dev, "GPIO%d output disabled\n", m); |
1a66fdf0 JC |
67 | amp->gpio_config(m, ~1, 0); |
68 | break; | |
69 | case 'T': | |
abecb6da | 70 | dev_dbg(dev, "GPIO%d output is push pull\n", m); |
1a66fdf0 JC |
71 | amp->gpio_config(m, ~2, 2); |
72 | break; | |
73 | case 't': | |
abecb6da | 74 | dev_dbg(dev, "GPIO%d output is open drain\n", m); |
1a66fdf0 JC |
75 | amp->gpio_config(m, ~2, 0); |
76 | break; | |
77 | case 'P': | |
f31000e5 | 78 | dev_dbg(dev, "GPIO%d pull up enabled\n", m); |
1a66fdf0 JC |
79 | amp->gpio_config(m, ~4, 4); |
80 | break; | |
81 | case 'p': | |
f31000e5 | 82 | dev_dbg(dev, "GPIO%d pull up disabled\n", m); |
1a66fdf0 JC |
83 | amp->gpio_config(m, ~4, 0); |
84 | break; | |
1a66fdf0 JC |
85 | case 'v': |
86 | /* View Current pin settings */ | |
f31000e5 | 87 | amp->gpio_dump(amp, m); |
1a66fdf0 JC |
88 | break; |
89 | case '\n': | |
90 | /* end of settings string, do nothing */ | |
91 | break; | |
92 | default: | |
f31000e5 JC |
93 | dev_err(dev, "io%2d bad setting: chr<0x%2x>\n", |
94 | m, (int)c); | |
1a66fdf0 JC |
95 | err++; |
96 | } | |
97 | } | |
98 | if (err) | |
99 | return -EINVAL; /* full string handled, report error */ | |
100 | ||
101 | return len; | |
102 | } | |
103 | ||
104 | ssize_t nsc_gpio_read(struct file *file, char __user * buf, | |
105 | size_t len, loff_t * ppos) | |
106 | { | |
496ad9aa | 107 | unsigned m = iminor(file_inode(file)); |
1a66fdf0 JC |
108 | int value; |
109 | struct nsc_gpio_ops *amp = file->private_data; | |
110 | ||
111 | value = amp->gpio_get(m); | |
112 | if (put_user(value ? '1' : '0', buf)) | |
113 | return -EFAULT; | |
114 | ||
115 | return 1; | |
116 | } | |
117 | ||
0e41ef3c | 118 | /* common file-ops routines for both scx200_gpio and pc87360_gpio */ |
1a66fdf0 JC |
119 | EXPORT_SYMBOL(nsc_gpio_write); |
120 | EXPORT_SYMBOL(nsc_gpio_read); | |
0e41ef3c | 121 | EXPORT_SYMBOL(nsc_gpio_dump); |
1ca5df0a JC |
122 | |
123 | static int __init nsc_gpio_init(void) | |
124 | { | |
125 | printk(KERN_DEBUG NAME " initializing\n"); | |
126 | return 0; | |
127 | } | |
128 | ||
129 | static void __exit nsc_gpio_cleanup(void) | |
130 | { | |
131 | printk(KERN_DEBUG NAME " cleanup\n"); | |
132 | } | |
133 | ||
1ca5df0a JC |
134 | module_init(nsc_gpio_init); |
135 | module_exit(nsc_gpio_cleanup); | |
1a66fdf0 JC |
136 | |
137 | MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>"); | |
138 | MODULE_DESCRIPTION("NatSemi GPIO Common Methods"); | |
139 | MODULE_LICENSE("GPL"); |