TI:OMAP: [PATCH 2/4] Enable I2C bus switching

GoogleGroups
1

From 9045377f255e8a59450a6957e63366b4963281ae Mon Sep 17 00:00:00 2001

2

Dear Khasim Syed,
I have compiled your patches and they appear to work on a C2 board.

One question/observation:

I can switch by 'i2c dev' to channel #0, #1, and #2. But #3 fails.
AFAIK, there are I2C1 to I2C4 on the OMAP3530. How is the mapping?
Which channel is missing?

And, for channel #0, I can probe addresses 48 to 4B, while channel #1
responds to almost all addresses and channel #2 to none.

Thanks for your good work!
Nikolaus

3

Dear Khasim Syed,
I have compiled your patches and they appear to work on a C2 board.

One question/observation:

I can switch by 'i2c dev' to channel #0, #1, and #2. But #3 fails.
AFAIK, there are I2C1 to I2C4 on the OMAP3530. How is the mapping?
Which channel is missing?

I2C4 is for smart reflex to Triton chipset, it is not generic so no
support was added for the same.

And, for channel #0, I can probe addresses 48 to 4B, while channel #1
responds to almost all addresses and channel #2 to none.

Channel 2 will respond when you have DVID monitor connected. Channel 1
has no device connected therefore it shows all sorts of addresses.

Thanks for your good work!

Thanks.

Regards,
Khasim

4

> Dear Khasim Syed,
> I have compiled your patches and they appear to work on a C2 board.

> One question/observation:

> I can switch by 'i2c dev' to channel #0, #1, and #2. But #3 fails.
> AFAIK, there are I2C1 to I2C4 on the OMAP3530. How is the mapping?
> Which channel is missing?

I2C4 is for smart reflex to Triton chipset, it is not generic so no
support was added for the same.

Ah, that is very reasonable...

> And, for channel #0, I can probe addresses 48 to 4B, while channel #1
> responds to almost all addresses and channel #2 to none.

Channel 2 will respond when you have DVID monitor connected. Channel 1
has no device connected therefore it shows all sorts of addresses.

So it is (for the records):

channel 0: I2C1 - control bus of TWL4030/TPS65950
channel 1: I2C2 - connected to Expansion Header J3
channel 2: I2C3 - level shifted to DVI connector and directly on video
expansion header J4/J5
n/a: I2C4 - smart reflex

> Thanks for your good work!

Thanks.

Regards,
Khasim

Another small observation: when I enter the i2c command without any
parameters, uboot appears to hang with no error message.