[U-Boot] [RFC 0/2] Add cdns-i2c driver as drop in for zynq-i2c

Moritz Fischer moritz.fischer at ettus.com
Tue Jan 5 18:30:50 CET 2016


Hi Michal,

On Tue, Jan 5, 2016 at 7:44 AM, Michal Simek <michal.simek at xilinx.com> wrote:

> I have looked at these patches and I don't know why there is 100k
> limitation in cdns_i2c_set_bus_speed. DTS is using 400k in Linux without
> any problem.

Well I could statically calculate the values for 400K, too but anyway that works
only if your CPU_CLK_1X is 111MHz. Is there a way to figure out the CPU_CLK_1X
frequency?

> Unfortunately I found that i2c muxes like pca9548 are not supported yet
> but I have create sort of skeleton for that but it looks like that there
> is no standard binding where i2c-parent is required. Also every muxes
> bus needs to have correct label and alias.

Yeah, I realized that last night when I started playing around with
it. I was trying
to pull in the linux one but didn't get around to finish that yet.

> Also I have found that there is eeprom dependency which needs to be
> resolved to be able to use this driver instead of old one.

Yeah I realized that. Do any of the zynq boards actually use CMD_EEPROM?

Thanks for you feedback,

Moritz


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