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authorHeiko Schocher <hs@denx.de>2012-10-25 10:32:14 +0200
committerHeiko Schocher <hs@denx.de>2013-07-23 08:34:53 +0200
commit9a2accb44f871af9c87c34d1c9ac95010f4e6f09 (patch)
treef4fdbb502b7cd8572f848e20db5321bc2f07d30d /README
parent00f792e0df9ae942427e44595a0f4379582accee (diff)
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i2c, multibus: get rid of CONFIG_I2C_MUX
CONFIG_I2C_MUX is replaced through the new i2c multibus/multiadapter framework, configured through CONFIG_SYS_I2C. As CONFIG_I2C_MUX is only used on the keymile boards, and they are now completely moved to the new framework, remove CONFIG_I2C_MUX. Signed-off-by: Heiko Schocher <hs@denx.de> Cc: Holger Brunck <holger.brunck@keymile.com> Tested-By: Holger Brunck <holger.brunck@keymile.com>
Diffstat (limited to 'README')
-rw-r--r--README47
1 files changed, 0 insertions, 47 deletions
diff --git a/README b/README
index 636107f..f00e41b 100644
--- a/README
+++ b/README
@@ -2225,53 +2225,6 @@ CBFS (Coreboot Filesystem) support
If not defined, then U-Boot uses predefined value for
specified DTT device.
- CONFIG_I2C_MUX
-
- Define this option if you have I2C devices reached over 1 .. n
- I2C Muxes like the pca9544a. This option addes a new I2C
- Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
- new I2C Bus to the existing I2C Busses. If you select the
- new Bus with "i2c dev", u-bbot sends first the commandos for
- the muxes to activate this new "bus".
-
- CONFIG_I2C_MULTI_BUS must be also defined, to use this
- feature!
-
- Example:
- Adding a new I2C Bus reached over 2 pca9544a muxes
- The First mux with address 70 and channel 6
- The Second mux with address 71 and channel 4
-
- => i2c bus pca9544a:70:6:pca9544a:71:4
-
- Use the "i2c bus" command without parameter, to get a list
- of I2C Busses with muxes:
-
- => i2c bus
- Busses reached over muxes:
- Bus ID: 2
- reached over Mux(es):
- pca9544a@70 ch: 4
- Bus ID: 3
- reached over Mux(es):
- pca9544a@70 ch: 6
- pca9544a@71 ch: 4
- =>
-
- If you now switch to the new I2C Bus 3 with "i2c dev 3"
- u-boot first sends the command to the mux@70 to enable
- channel 6, and then the command to the mux@71 to enable
- the channel 4.
-
- After that, you can use the "normal" i2c commands as
- usual to communicate with your I2C devices behind
- the 2 muxes.
-
- This option is actually implemented for the bitbanging
- algorithm in common/soft_i2c.c and for the Hardware I2C
- Bus on the MPC8260. But it should be not so difficult
- to add this option to other architectures.
-
CONFIG_SOFT_I2C_READ_REPEATED_START
defining this will force the i2c_read() function in