xref: /openbmc/u-boot/cmd/terminal.c (revision a3b15a05)
1 /*
2  * (C) Copyright 2007 OpenMoko, Inc.
3  * Written by Harald Welte <laforge@openmoko.org>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /*
9  * Boot support
10  */
11 #include <common.h>
12 #include <command.h>
13 #include <stdio_dev.h>
14 #include <serial.h>
15 
16 int do_terminal(cmd_tbl_t * cmd, int flag, int argc, char * const argv[])
17 {
18 	int last_tilde = 0;
19 	struct stdio_dev *dev = NULL;
20 
21 	if (argc < 1)
22 		return -1;
23 
24 	/* Scan for selected output/input device */
25 	dev = stdio_get_by_name(argv[1]);
26 	if (!dev)
27 		return -1;
28 
29 	serial_reinit_all();
30 	printf("Entering terminal mode for port %s\n", dev->name);
31 	puts("Use '~.' to leave the terminal and get back to u-boot\n");
32 
33 	while (1) {
34 		int c;
35 
36 		/* read from console and display on serial port */
37 		if (stdio_devices[0]->tstc()) {
38 			c = stdio_devices[0]->getc();
39 			if (last_tilde == 1) {
40 				if (c == '.') {
41 					putc(c);
42 					putc('\n');
43 					break;
44 				} else {
45 					last_tilde = 0;
46 					/* write the delayed tilde */
47 					dev->putc('~');
48 					/* fall-through to print current
49 					 * character */
50 				}
51 			}
52 			if (c == '~') {
53 				last_tilde = 1;
54 				puts("[u-boot]");
55 				putc(c);
56 			}
57 			dev->putc(c);
58 		}
59 
60 		/* read from serial port and display on console */
61 		if (dev->tstc()) {
62 			c = dev->getc();
63 			putc(c);
64 		}
65 	}
66 	return 0;
67 }
68 
69 
70 /***************************************************/
71 
72 U_BOOT_CMD(
73 	terminal,	3,	1,	do_terminal,
74 	"start terminal emulator",
75 	""
76 );
77