[U-Boot] [PATCH] arm: socfpga: Enable DM_I2C

[Stefan Roese <sr@denx.de>]

On 18.03.2016 12:20, Marek Vasut wrote:
> On 03/18/2016 08:55 AM, Stefan Roese wrote:
>> The designware I2C driver now supports DM. So lets use it and enable
>> DM_I2C for this platform per default.
>>
>> Signed-off-by: Stefan Roese <sr@denx.de>
>> Cc: Marek Vasut <marex@denx.de>
>> ---
>>   arch/arm/Kconfig                 |  1 +
>>   arch/arm/dts/socfpga.dtsi        |  4 ++++
>>   include/configs/socfpga_common.h | 16 ----------------
>>   3 files changed, 5 insertions(+), 16 deletions(-)
>>
>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>> index e5f57ef..98c1f10 100644
>> --- a/arch/arm/Kconfig
>> +++ b/arch/arm/Kconfig
>> @@ -516,6 +516,7 @@ config ARCH_SOCFPGA
>>   	select DM
>>   	select DM_SPI_FLASH
>>   	select DM_SPI
>> +	select DM_I2C
>>
>>   config TARGET_CM_T43
>>   	bool "Support cm_t43"
>> diff --git a/arch/arm/dts/socfpga.dtsi b/arch/arm/dts/socfpga.dtsi
>> index 8588221..fe55722 100644
>> --- a/arch/arm/dts/socfpga.dtsi
>> +++ b/arch/arm/dts/socfpga.dtsi
>> @@ -23,6 +23,10 @@
>>   		spi0 = &qspi;
>>   		spi1 = &spi0;
>>   		spi2 = &spi1;
>> +		i2c0 = &i2c0;
>> +		i2c1 = &i2c1;
>> +		i2c2 = &i2c2;
>> +		i2c3 = &i2c3;
>
> Something tells me that you should be super-careful here, because some
> socfpga boards actually do use i2c. But just adding the aliases here
> without actually enabling the i2c via DT now will cause breakage.

Right. But if the boards are also used in Linux and the dts is synced
with the Linux one, then the I2C DT node should be enabled, right?

> One way to solve it is to enable all four buses in socfpga-cyclone5.dtsi
> but that's not something I find very appealing.

I don't like it. In the Linux socpfga.dtsi the I2C DT nodes are also
disabled per default. We should stay in sync here.

> The other is to keep the
> patch this way and wait until someone complains his i2c is not working.
>
> What do you think ?

Or we could move the aliases into the board specific dts files? I
could start with the SR1500 board.

What do you think?

Thanks,
Stefan