xref: /openbmc/u-boot/post/drivers/i2c.c (revision 60aaaa0782848062d0f499382035acc09eaff352)
1 /*
2  * (C) Copyright 2002
3  * Wolfgang Denk, DENX Software Engineering, wd@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 /*
25  * I2C test
26  *
27  * For verifying the I2C bus, a full I2C bus scanning is performed.
28  *
29  * #ifdef CONFIG_SYS_POST_I2C_ADDRS
30  *   The test is considered as passed if all the devices and
31  *   only the devices in the list are found.
32  * #else [ ! CONFIG_SYS_POST_I2C_ADDRS ]
33  *   The test is considered as passed if any I2C device is found.
34  * #endif
35  */
36 
37 #include <common.h>
38 #include <post.h>
39 #include <i2c.h>
40 
41 #if CONFIG_POST & CONFIG_SYS_POST_I2C
42 
43 int i2c_post_test (int flags)
44 {
45 	unsigned int i;
46 #ifndef CONFIG_SYS_POST_I2C_ADDRS
47 	/* Start at address 1, address 0 is the general call address */
48 	for (i = 1; i < 128; i++)
49 		if (i2c_probe (i) == 0)
50 			return 0;
51 
52 	/* No devices found */
53 	return -1;
54 #else
55 	unsigned int ret  = 0;
56 	int j;
57 	const unsigned char i2c_addr_list[] = CONFIG_SYS_POST_I2C_ADDRS;
58 
59 	/* Start at address 1, address 0 is the general call address */
60 	for (i = 1; i < 128; i++) {
61 		if (i2c_probe(i) != 0)
62 			continue;
63 
64 		for (j = 0; j < sizeof(i2c_addr_list); ++j) {
65 			if (i == i2c_addr_list[j]) {
66 				i2c_addr_list[j] = 0xff;
67 				break;
68 			}
69 		}
70 
71 		if (j == sizeof(i2c_addr_list)) {
72 			ret = -1;
73 			post_log("I2C: addr %02x not expected\n", i);
74 		}
75 	}
76 
77 	for (i = 0; i < sizeof(i2c_addr_list); ++i) {
78 		if (i2c_addr_list[i] == 0xff)
79 			continue;
80 		post_log("I2C: addr %02x did not respond\n", i2c_addr_list[i]);
81 		ret = -1;
82 	}
83 
84 	return ret;
85 #endif
86 }
87 
88 #endif /* CONFIG_POST & CONFIG_SYS_POST_I2C */
89