[U-Boot] [[PATCH v3 2/2] gpio: omap5-uevm: Configure the tca6424 gpio expander

Dan Murphy
2013-07-12T17:30:36Z

NM

On 07/11/2013 01:02 PM, Nishanth Menon wrote:
<snip>
>>> diff --git a/board/ti/omap5_uevm/mux_data.h
> b/board/ti/omap5_uevm/mux_data.h
>>>> index a82795d..7e6415e 100644
>>>> --- a/board/ti/omap5_uevm/mux_data.h
>>>> +++ b/board/ti/omap5_uevm/mux_data.h
>>>> @@ -56,6 +56,8 @@ const struct pad_conf_entry
> core_padconf_array_essential[] = {
>>>> {USBD0_HS_DP, (IEN | M0)}, /* USBD0_HS_DP */
>>>> {USBD0_HS_DM, (IEN | M0)}, /* USBD0_HS_DM */
>>>> {USBD0_SS_RX, (IEN | M0)}, /* USBD0_SS_RX */
>>>> + {I2C5_SCL, (IEN | M0)}, /* I2C5_SCL */
>>> nit pick -> SCL (or i2c clk) is out put from master - always. IEN
> enables full duplex, but anyways.. just a nitpick :)
>> OK I changed this and did a test and reads fail without the IEN set.
>> This is to sync the client clocks.
> Scl? I2c clock? Does not work without input- something is fishy no?
Nope. There is clock synchronization and clock arbitration that happens and the I2C master needs to see the SCL as an input.

Kernel configures the I2C mux for 1 and 5 the same way.
<snip>

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Dan Murphy