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 /arch/v850/kernel/memcons.c |
Linux-2.6.12-rc2v2.6.12-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 'arch/v850/kernel/memcons.c')
-rw-r--r-- | arch/v850/kernel/memcons.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/v850/kernel/memcons.c b/arch/v850/kernel/memcons.c new file mode 100644 index 000000000000..491614c435cd --- /dev/null +++ b/arch/v850/kernel/memcons.c | |||
@@ -0,0 +1,135 @@ | |||
1 | /* | ||
2 | * arch/v850/kernel/memcons.c -- Console I/O to a memory buffer | ||
3 | * | ||
4 | * Copyright (C) 2001,02 NEC Corporation | ||
5 | * Copyright (C) 2001,02 Miles Bader <miles@gnu.org> | ||
6 | * | ||
7 | * This file is subject to the terms and conditions of the GNU General | ||
8 | * Public License. See the file COPYING in the main directory of this | ||
9 | * archive for more details. | ||
10 | * | ||
11 | * Written by Miles Bader <miles@gnu.org> | ||
12 | */ | ||
13 | |||
14 | #include <linux/kernel.h> | ||
15 | #include <linux/console.h> | ||
16 | #include <linux/tty.h> | ||
17 | #include <linux/tty_driver.h> | ||
18 | #include <linux/init.h> | ||
19 | |||
20 | /* If this device is enabled, the linker map should define start and | ||
21 | end points for its buffer. */ | ||
22 | extern char memcons_output[], memcons_output_end; | ||
23 | |||
24 | /* Current offset into the buffer. */ | ||
25 | static unsigned long memcons_offs = 0; | ||
26 | |||
27 | /* Spinlock protecting memcons_offs. */ | ||
28 | static DEFINE_SPINLOCK(memcons_lock); | ||
29 | |||
30 | |||
31 | static size_t write (const char *buf, size_t len) | ||
32 | { | ||
33 | int flags; | ||
34 | char *point; | ||
35 | |||
36 | spin_lock_irqsave (memcons_lock, flags); | ||
37 | |||
38 | point = memcons_output + memcons_offs; | ||
39 | if (point + len >= &memcons_output_end) { | ||
40 | len = &memcons_output_end - point; | ||
41 | memcons_offs = 0; | ||
42 | } else | ||
43 | memcons_offs += len; | ||
44 | |||
45 | spin_unlock_irqrestore (memcons_lock, flags); | ||
46 | |||
47 | memcpy (point, buf, len); | ||
48 | |||
49 | return len; | ||
50 | } | ||
51 | |||
52 | |||
53 | /* Low-level console. */ | ||
54 | |||
55 | static void memcons_write (struct console *co, const char *buf, unsigned len) | ||
56 | { | ||
57 | while (len > 0) | ||
58 | len -= write (buf, len); | ||
59 | } | ||
60 | |||
61 | static struct tty_driver *tty_driver; | ||
62 | |||
63 | static struct tty_driver *memcons_device (struct console *co, int *index) | ||
64 | { | ||
65 | *index = co->index; | ||
66 | return tty_driver; | ||
67 | } | ||
68 | |||
69 | static struct console memcons = | ||
70 | { | ||
71 | .name = "memcons", | ||
72 | .write = memcons_write, | ||
73 | .device = memcons_device, | ||
74 | .flags = CON_PRINTBUFFER, | ||
75 | .index = -1, | ||
76 | }; | ||
77 | |||
78 | void memcons_setup (void) | ||
79 | { | ||
80 | register_console (&memcons); | ||
81 | printk (KERN_INFO "Console: static memory buffer (memcons)\n"); | ||
82 | } | ||
83 | |||
84 | /* Higher level TTY interface. */ | ||
85 | |||
86 | int memcons_tty_open (struct tty_struct *tty, struct file *filp) | ||
87 | { | ||
88 | return 0; | ||
89 | } | ||
90 | |||
91 | int memcons_tty_write (struct tty_struct *tty, const unsigned char *buf, int len) | ||
92 | { | ||
93 | return write (buf, len); | ||
94 | } | ||
95 | |||
96 | int memcons_tty_write_room (struct tty_struct *tty) | ||
97 | { | ||
98 | return &memcons_output_end - (memcons_output + memcons_offs); | ||
99 | } | ||
100 | |||
101 | int memcons_tty_chars_in_buffer (struct tty_struct *tty) | ||
102 | { | ||
103 | /* We have no buffer. */ | ||
104 | return 0; | ||
105 | } | ||
106 | |||
107 | static struct tty_operations ops = { | ||
108 | .open = memcons_tty_open, | ||
109 | .write = memcons_tty_write, | ||
110 | .write_room = memcons_tty_write_room, | ||
111 | .chars_in_buffer = memcons_tty_chars_in_buffer, | ||
112 | }; | ||
113 | |||
114 | int __init memcons_tty_init (void) | ||
115 | { | ||
116 | int err; | ||
117 | struct tty_driver *driver = alloc_tty_driver(1); | ||
118 | if (!driver) | ||
119 | return -ENOMEM; | ||
120 | |||
121 | driver->name = "memcons"; | ||
122 | driver->major = TTY_MAJOR; | ||
123 | driver->minor_start = 64; | ||
124 | driver->type = TTY_DRIVER_TYPE_SYSCONS; | ||
125 | driver->init_termios = tty_std_termios; | ||
126 | tty_set_operations(driver, &ops); | ||
127 | err = tty_register_driver(driver); | ||
128 | if (err) { | ||
129 | put_tty_driver(driver); | ||
130 | return err; | ||
131 | } | ||
132 | tty_driver = driver; | ||
133 | return 0; | ||
134 | } | ||
135 | __initcall (memcons_tty_init); | ||