xref: /openbmc/u-boot/common/iomux.c (revision ad5b5801)
1 /*
2  * (C) Copyright 2008
3  * Gary Jennejohn, DENX Software Engineering GmbH, garyj@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <console.h>
10 #include <serial.h>
11 #include <malloc.h>
12 
13 #ifdef CONFIG_CONSOLE_MUX
14 void iomux_printdevs(const int console)
15 {
16 	int i;
17 	struct stdio_dev *dev;
18 
19 	for (i = 0; i < cd_count[console]; i++) {
20 		dev = console_devices[console][i];
21 		printf("%s ", dev->name);
22 	}
23 	printf("\n");
24 }
25 
26 /* This tries to preserve the old list if an error occurs. */
27 int iomux_doenv(const int console, const char *arg)
28 {
29 	char *console_args, *temp, **start;
30 	int i, j, k, io_flag, cs_idx, repeat;
31 	struct stdio_dev *dev;
32 	struct stdio_dev **cons_set;
33 
34 	console_args = strdup(arg);
35 	if (console_args == NULL)
36 		return 1;
37 	/*
38 	 * Check whether a comma separated list of devices was
39 	 * entered and count how many devices were entered.
40 	 * The array start[] has pointers to the beginning of
41 	 * each device name (up to MAX_CONSARGS devices).
42 	 *
43 	 * Have to do this twice - once to count the number of
44 	 * commas and then again to populate start.
45 	 */
46 	i = 0;
47 	temp = console_args;
48 	for (;;) {
49 		temp = strchr(temp, ',');
50 		if (temp != NULL) {
51 			i++;
52 			temp++;
53 			continue;
54 		}
55 		/* There's always one entry more than the number of commas. */
56 		i++;
57 		break;
58 	}
59 	start = (char **)malloc(i * sizeof(char *));
60 	if (start == NULL) {
61 		free(console_args);
62 		return 1;
63 	}
64 	i = 0;
65 	start[0] = console_args;
66 	for (;;) {
67 		temp = strchr(start[i++], ',');
68 		if (temp == NULL)
69 			break;
70 		*temp = '\0';
71 		start[i] = temp + 1;
72 	}
73 	cons_set = (struct stdio_dev **)calloc(i, sizeof(struct stdio_dev *));
74 	if (cons_set == NULL) {
75 		free(start);
76 		free(console_args);
77 		return 1;
78 	}
79 
80 	switch (console) {
81 	case stdin:
82 		io_flag = DEV_FLAGS_INPUT;
83 		break;
84 	case stdout:
85 	case stderr:
86 		io_flag = DEV_FLAGS_OUTPUT;
87 		break;
88 	default:
89 		free(start);
90 		free(console_args);
91 		free(cons_set);
92 		return 1;
93 	}
94 
95 	cs_idx = 0;
96 	for (j = 0; j < i; j++) {
97 		/*
98 		 * Check whether the device exists and is valid.
99 		 * console_assign() also calls search_device(),
100 		 * but I need the pointer to the device.
101 		 */
102 		dev = search_device(io_flag, start[j]);
103 		if (dev == NULL)
104 			continue;
105 		/*
106 		 * Prevent multiple entries for a device.
107 		 */
108 		 repeat = 0;
109 		 for (k = 0; k < cs_idx; k++) {
110 			if (dev == cons_set[k]) {
111 				repeat++;
112 				break;
113 			}
114 		 }
115 		 if (repeat)
116 			continue;
117 		/*
118 		 * Try assigning the specified device.
119 		 * This could screw up the console settings for apps.
120 		 */
121 		if (console_assign(console, start[j]) < 0)
122 			continue;
123 		cons_set[cs_idx++] = dev;
124 	}
125 	free(console_args);
126 	free(start);
127 	/* failed to set any console */
128 	if (cs_idx == 0) {
129 		free(cons_set);
130 		return 1;
131 	} else {
132 		/* Works even if console_devices[console] is NULL. */
133 		console_devices[console] =
134 			(struct stdio_dev **)realloc(console_devices[console],
135 			cs_idx * sizeof(struct stdio_dev *));
136 		if (console_devices[console] == NULL) {
137 			free(cons_set);
138 			return 1;
139 		}
140 		memcpy(console_devices[console], cons_set, cs_idx *
141 			sizeof(struct stdio_dev *));
142 
143 		cd_count[console] = cs_idx;
144 	}
145 	free(cons_set);
146 	return 0;
147 }
148 #endif /* CONFIG_CONSOLE_MUX */
149