diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/char/generic_nvram.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/char/generic_nvram.c')
-rw-r--r-- | drivers/char/generic_nvram.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/drivers/char/generic_nvram.c b/drivers/char/generic_nvram.c new file mode 100644 index 000000000000..1b5e01e6e129 --- /dev/null +++ b/drivers/char/generic_nvram.c | |||
@@ -0,0 +1,145 @@ | |||
1 | /* | ||
2 | * Generic /dev/nvram driver for architectures providing some | ||
3 | * "generic" hooks, that is : | ||
4 | * | ||
5 | * nvram_read_byte, nvram_write_byte, nvram_sync | ||
6 | * | ||
7 | * Note that an additional hook is supported for PowerMac only | ||
8 | * for getting the nvram "partition" informations | ||
9 | * | ||
10 | */ | ||
11 | |||
12 | #define NVRAM_VERSION "1.1" | ||
13 | |||
14 | #include <linux/module.h> | ||
15 | |||
16 | #include <linux/types.h> | ||
17 | #include <linux/errno.h> | ||
18 | #include <linux/fs.h> | ||
19 | #include <linux/miscdevice.h> | ||
20 | #include <linux/fcntl.h> | ||
21 | #include <linux/init.h> | ||
22 | #include <linux/smp_lock.h> | ||
23 | #include <asm/uaccess.h> | ||
24 | #include <asm/nvram.h> | ||
25 | |||
26 | #define NVRAM_SIZE 8192 | ||
27 | |||
28 | static loff_t nvram_llseek(struct file *file, loff_t offset, int origin) | ||
29 | { | ||
30 | lock_kernel(); | ||
31 | switch (origin) { | ||
32 | case 1: | ||
33 | offset += file->f_pos; | ||
34 | break; | ||
35 | case 2: | ||
36 | offset += NVRAM_SIZE; | ||
37 | break; | ||
38 | } | ||
39 | if (offset < 0) { | ||
40 | unlock_kernel(); | ||
41 | return -EINVAL; | ||
42 | } | ||
43 | file->f_pos = offset; | ||
44 | unlock_kernel(); | ||
45 | return file->f_pos; | ||
46 | } | ||
47 | |||
48 | static ssize_t read_nvram(struct file *file, char __user *buf, | ||
49 | size_t count, loff_t *ppos) | ||
50 | { | ||
51 | unsigned int i; | ||
52 | char __user *p = buf; | ||
53 | |||
54 | if (!access_ok(VERIFY_WRITE, buf, count)) | ||
55 | return -EFAULT; | ||
56 | if (*ppos >= NVRAM_SIZE) | ||
57 | return 0; | ||
58 | for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) | ||
59 | if (__put_user(nvram_read_byte(i), p)) | ||
60 | return -EFAULT; | ||
61 | *ppos = i; | ||
62 | return p - buf; | ||
63 | } | ||
64 | |||
65 | static ssize_t write_nvram(struct file *file, const char __user *buf, | ||
66 | size_t count, loff_t *ppos) | ||
67 | { | ||
68 | unsigned int i; | ||
69 | const char __user *p = buf; | ||
70 | char c; | ||
71 | |||
72 | if (!access_ok(VERIFY_READ, buf, count)) | ||
73 | return -EFAULT; | ||
74 | if (*ppos >= NVRAM_SIZE) | ||
75 | return 0; | ||
76 | for (i = *ppos; count > 0 && i < NVRAM_SIZE; ++i, ++p, --count) { | ||
77 | if (__get_user(c, p)) | ||
78 | return -EFAULT; | ||
79 | nvram_write_byte(c, i); | ||
80 | } | ||
81 | *ppos = i; | ||
82 | return p - buf; | ||
83 | } | ||
84 | |||
85 | static int nvram_ioctl(struct inode *inode, struct file *file, | ||
86 | unsigned int cmd, unsigned long arg) | ||
87 | { | ||
88 | switch(cmd) { | ||
89 | #ifdef CONFIG_PPC_PMAC | ||
90 | case OBSOLETE_PMAC_NVRAM_GET_OFFSET: | ||
91 | printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n"); | ||
92 | case IOC_NVRAM_GET_OFFSET: { | ||
93 | int part, offset; | ||
94 | |||
95 | if (_machine != _MACH_Pmac) | ||
96 | return -EINVAL; | ||
97 | if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0) | ||
98 | return -EFAULT; | ||
99 | if (part < pmac_nvram_OF || part > pmac_nvram_NR) | ||
100 | return -EINVAL; | ||
101 | offset = pmac_get_partition(part); | ||
102 | if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0) | ||
103 | return -EFAULT; | ||
104 | break; | ||
105 | } | ||
106 | #endif /* CONFIG_PPC_PMAC */ | ||
107 | case IOC_NVRAM_SYNC: | ||
108 | nvram_sync(); | ||
109 | break; | ||
110 | default: | ||
111 | return -EINVAL; | ||
112 | } | ||
113 | |||
114 | return 0; | ||
115 | } | ||
116 | |||
117 | struct file_operations nvram_fops = { | ||
118 | .owner = THIS_MODULE, | ||
119 | .llseek = nvram_llseek, | ||
120 | .read = read_nvram, | ||
121 | .write = write_nvram, | ||
122 | .ioctl = nvram_ioctl, | ||
123 | }; | ||
124 | |||
125 | static struct miscdevice nvram_dev = { | ||
126 | NVRAM_MINOR, | ||
127 | "nvram", | ||
128 | &nvram_fops | ||
129 | }; | ||
130 | |||
131 | int __init nvram_init(void) | ||
132 | { | ||
133 | printk(KERN_INFO "Macintosh non-volatile memory driver v%s\n", | ||
134 | NVRAM_VERSION); | ||
135 | return misc_register(&nvram_dev); | ||
136 | } | ||
137 | |||
138 | void __exit nvram_cleanup(void) | ||
139 | { | ||
140 | misc_deregister( &nvram_dev ); | ||
141 | } | ||
142 | |||
143 | module_init(nvram_init); | ||
144 | module_exit(nvram_cleanup); | ||
145 | MODULE_LICENSE("GPL"); | ||