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authorWolfgang Denk <wd@denx.de>2010-10-23 21:59:42 +0200
committerWolfgang Denk <wd@denx.de>2010-10-23 21:59:42 +0200
commitf2b382ea066d02d5ba44870024cc1295e85782ef (patch)
tree9891424412f40e0bbe3cb64d022597bffa301b50 /doc
parent33a08c10c78baf67e41cd03d5732ddc338e8c2e9 (diff)
parentbfe18815e8123f4456be8b5858b2b255d7881698 (diff)
downloadu-boot-linaro-stable-f2b382ea066d02d5ba44870024cc1295e85782ef.tar.gz
Merge branch 'master' of git://git.denx.de/u-boot-mpc85xx
Diffstat (limited to 'doc')
-rw-r--r--doc/README.POST19
1 files changed, 13 insertions, 6 deletions
diff --git a/doc/README.POST b/doc/README.POST
index eeb218d39..6815d491c 100644
--- a/doc/README.POST
+++ b/doc/README.POST
@@ -659,12 +659,19 @@ not need any modifications for porting them to another board/CPU.
2.2.2.1. I2C test
For verifying the I2C bus, a full I2C bus scanning will be performed
-using the i2c_probe() routine. If any I2C device is found, the test
-will be considered as passed, otherwise failed. This particular way
-will be used because it provides the most common method of testing.
-For example, using the internal loopback mode of the CPM I2C
-controller for testing would not work on boards where the software
-I2C driver (also known as bit-banged driver) is used.
+using the i2c_probe() routine. If a board defines
+CONFIG_SYS_POST_I2C_ADDRS the I2C test will pass if all devices
+listed in CONFIG_SYS_POST_I2C_ADDRS are found, and no additional
+devices are detected. If CONFIG_SYS_POST_I2C_ADDRS is not defined
+the test will pass if any I2C device is found.
+
+The CONFIG_SYS_POST_I2C_IGNORES define can be used to list I2C
+devices which may or may not be present when using
+CONFIG_SYS_POST_I2C_ADDRS. The I2C POST test will pass regardless
+if the devices in CONFIG_SYS_POST_I2C_IGNORES are found or not.
+This is useful in cases when I2C devices are optional (eg on a
+daughtercard that may or may not be present) or not critical
+to board operation.
2.2.2.2. Watchdog timer test