xref: /openbmc/u-boot/common/iomux.c (revision 63495ad7)
1 /*
2  * (C) Copyright 2008
3  * Gary Jennejohn, DENX Software Engineering GmbH, garyj@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <serial.h>
26 #include <malloc.h>
27 
28 #ifdef CONFIG_CONSOLE_MUX
29 void iomux_printdevs(const int console)
30 {
31 	int i;
32 	struct stdio_dev *dev;
33 
34 	for (i = 0; i < cd_count[console]; i++) {
35 		dev = console_devices[console][i];
36 		printf("%s ", dev->name);
37 	}
38 	printf("\n");
39 }
40 
41 /* This tries to preserve the old list if an error occurs. */
42 int iomux_doenv(const int console, const char *arg)
43 {
44 	char *console_args, *temp, **start;
45 	int i, j, k, io_flag, cs_idx, repeat;
46 	struct stdio_dev *dev;
47 	struct stdio_dev **cons_set;
48 
49 	console_args = strdup(arg);
50 	if (console_args == NULL)
51 		return 1;
52 	/*
53 	 * Check whether a comma separated list of devices was
54 	 * entered and count how many devices were entered.
55 	 * The array start[] has pointers to the beginning of
56 	 * each device name (up to MAX_CONSARGS devices).
57 	 *
58 	 * Have to do this twice - once to count the number of
59 	 * commas and then again to populate start.
60 	 */
61 	i = 0;
62 	temp = console_args;
63 	for (;;) {
64 		temp = strchr(temp, ',');
65 		if (temp != NULL) {
66 			i++;
67 			temp++;
68 			continue;
69 		}
70 		/* There's always one entry more than the number of commas. */
71 		i++;
72 		break;
73 	}
74 	start = (char **)malloc(i * sizeof(char *));
75 	if (start == NULL) {
76 		free(console_args);
77 		return 1;
78 	}
79 	i = 0;
80 	start[0] = console_args;
81 	for (;;) {
82 		temp = strchr(start[i++], ',');
83 		if (temp == NULL)
84 			break;
85 		*temp = '\0';
86 		start[i] = temp + 1;
87 	}
88 	cons_set = (struct stdio_dev **)calloc(i, sizeof(struct stdio_dev *));
89 	if (cons_set == NULL) {
90 		free(start);
91 		free(console_args);
92 		return 1;
93 	}
94 
95 	switch (console) {
96 	case stdin:
97 		io_flag = DEV_FLAGS_INPUT;
98 		break;
99 	case stdout:
100 	case stderr:
101 		io_flag = DEV_FLAGS_OUTPUT;
102 		break;
103 	default:
104 		free(start);
105 		free(console_args);
106 		free(cons_set);
107 		return 1;
108 	}
109 
110 	cs_idx = 0;
111 	for (j = 0; j < i; j++) {
112 		/*
113 		 * Check whether the device exists and is valid.
114 		 * console_assign() also calls search_device(),
115 		 * but I need the pointer to the device.
116 		 */
117 		dev = search_device(io_flag, start[j]);
118 		if (dev == NULL)
119 			continue;
120 		/*
121 		 * Prevent multiple entries for a device.
122 		 */
123 		 repeat = 0;
124 		 for (k = 0; k < cs_idx; k++) {
125 			if (dev == cons_set[k]) {
126 				repeat++;
127 				break;
128 			}
129 		 }
130 		 if (repeat)
131 			continue;
132 		/*
133 		 * Try assigning the specified device.
134 		 * This could screw up the console settings for apps.
135 		 */
136 		if (console_assign(console, start[j]) < 0)
137 			continue;
138 		cons_set[cs_idx++] = dev;
139 	}
140 	free(console_args);
141 	free(start);
142 	/* failed to set any console */
143 	if (cs_idx == 0) {
144 		free(cons_set);
145 		return 1;
146 	} else {
147 		/* Works even if console_devices[console] is NULL. */
148 		console_devices[console] =
149 			(struct stdio_dev **)realloc(console_devices[console],
150 			cs_idx * sizeof(struct stdio_dev *));
151 		if (console_devices[console] == NULL) {
152 			free(cons_set);
153 			return 1;
154 		}
155 		memcpy(console_devices[console], cons_set, cs_idx *
156 			sizeof(struct stdio_dev *));
157 
158 		cd_count[console] = cs_idx;
159 	}
160 	free(cons_set);
161 	return 0;
162 }
163 #endif /* CONFIG_CONSOLE_MUX */
164