[POWERPC] Fix constantness of bootwrapper arg
[linux-2.6.git] / arch / powerpc / boot / serial.c
1 /*
2  * Generic serial console support
3  *
4  * Author: Mark A. Greer <mgreer@mvista.com>
5  *
6  * Code in serial_edit_cmdline() copied from <file:arch/ppc/boot/simple/misc.c>
7  * and was written by Matt Porter <mporter@kernel.crashing.org>.
8  *
9  * 2001,2006 (c) MontaVista Software, Inc.  This file is licensed under
10  * the terms of the GNU General Public License version 2.  This program
11  * is licensed "as is" without any warranty of any kind, whether express
12  * or implied.
13  */
14 #include <stdarg.h>
15 #include <stddef.h>
16 #include "types.h"
17 #include "string.h"
18 #include "stdio.h"
19 #include "io.h"
20 #include "ops.h"
21
22 extern void udelay(long delay);
23
24 static int serial_open(void)
25 {
26         struct serial_console_data *scdp = console_ops.data;
27         return scdp->open();
28 }
29
30 static void serial_write(const char *buf, int len)
31 {
32         struct serial_console_data *scdp = console_ops.data;
33
34         while (*buf != '\0')
35                 scdp->putc(*buf++);
36 }
37
38 static void serial_edit_cmdline(char *buf, int len)
39 {
40         int timer = 0, count;
41         char ch, *cp;
42         struct serial_console_data *scdp = console_ops.data;
43
44         cp = buf;
45         count = strlen(buf);
46         cp = &buf[count];
47         count++;
48
49         while (timer++ < 5*1000) {
50                 if (scdp->tstc()) {
51                         while (((ch = scdp->getc()) != '\n') && (ch != '\r')) {
52                                 /* Test for backspace/delete */
53                                 if ((ch == '\b') || (ch == '\177')) {
54                                         if (cp != buf) {
55                                                 cp--;
56                                                 count--;
57                                                 printf("\b \b");
58                                         }
59                                 /* Test for ^x/^u (and wipe the line) */
60                                 } else if ((ch == '\030') || (ch == '\025')) {
61                                         while (cp != buf) {
62                                                 cp--;
63                                                 count--;
64                                                 printf("\b \b");
65                                         }
66                                 } else if (count < len) {
67                                                 *cp++ = ch;
68                                                 count++;
69                                                 scdp->putc(ch);
70                                 }
71                         }
72                         break;  /* Exit 'timer' loop */
73                 }
74                 udelay(1000);  /* 1 msec */
75         }
76         *cp = 0;
77 }
78
79 static void serial_close(void)
80 {
81         struct serial_console_data *scdp = console_ops.data;
82
83         if (scdp->close)
84                 scdp->close();
85 }
86
87 static void *serial_get_stdout_devp(void)
88 {
89         void *devp;
90         char devtype[MAX_PROP_LEN];
91         char path[MAX_PATH_LEN];
92
93         devp = finddevice("/chosen");
94         if (devp == NULL)
95                 goto err_out;
96
97         if (getprop(devp, "linux,stdout-path", path, MAX_PATH_LEN) > 0) {
98                 devp = finddevice(path);
99                 if (devp == NULL)
100                         goto err_out;
101
102                 if ((getprop(devp, "device_type", devtype, sizeof(devtype)) > 0)
103                                 && !strcmp(devtype, "serial"))
104                         return devp;
105         }
106 err_out:
107         return NULL;
108 }
109
110 static struct serial_console_data serial_cd;
111
112 /* Node's "compatible" property determines which serial driver to use */
113 int serial_console_init(void)
114 {
115         void *devp;
116         int rc = -1;
117         char compat[MAX_PROP_LEN];
118
119         devp = serial_get_stdout_devp();
120         if (devp == NULL)
121                 goto err_out;
122
123         if (getprop(devp, "compatible", compat, sizeof(compat)) < 0)
124                 goto err_out;
125
126         if (!strcmp(compat, "ns16550"))
127                 rc = ns16550_console_init(devp, &serial_cd);
128         else if (!strcmp(compat, "marvell,mpsc"))
129                 rc = mpsc_console_init(devp, &serial_cd);
130
131         /* Add other serial console driver calls here */
132
133         if (!rc) {
134                 console_ops.open = serial_open;
135                 console_ops.write = serial_write;
136                 console_ops.edit_cmdline = serial_edit_cmdline;
137                 console_ops.close = serial_close;
138                 console_ops.data = &serial_cd;
139
140                 return 0;
141         }
142 err_out:
143         return -1;
144 }