Reset i2c slave devices during init on mpc5xxx cpus
Reset any i2c devices that may have been interrupted during a system reset.
Normally this would be accomplished by clocking the line until SCL and SDA
are released and then sending a start condtiion (From an Atmel datasheet).
There is no direct access to the i2c pins so instead create start commands
through the i2c interface. Send a start command then delay for the SDA Hold
time, repeat this by disabling/enabling the bus a total of 9 times.
Signed-off-by: Eric Millbrandt <emillbrandt@dekaresearch.com>
diff --git a/README b/README
index c90f6ee..ff4ed8b 100644
--- a/README
+++ b/README
@@ -1366,6 +1366,13 @@
therefore be cleared to 0 (See, eg, MPC823e User's Manual
p.16-473). So, set CONFIG_SYS_I2C_SLAVE to 0.
+ CONFIG_SYS_I2C_INIT_MPC5XXX
+
+ When a board is reset during an i2c bus transfer
+ chips might think that the current transfer is still
+ in progress. Reset the slave devices by sending start
+ commands until the slave device responds.
+
That's all that's required for CONFIG_HARD_I2C.
If you use the software i2c interface (CONFIG_SOFT_I2C)