Hi Stefan,

On Mon, Sep 22, 2014 at 6:25 PM, Stefan Wahren [off-list ref] wrote:

i've ported the mxs-regulator driver and now i'm getting an probing output
like above with Linux 3.17-rc4.

Great, it looks like you are making good progress :-)

Now i want to test the mxs-regulator driver with the cpufreq-cpu0 as
consumer. So i defined cpu at 0 according to cpufreq-cpu0 binding in imx28.dtsi
and enabled cpufreq-cpu0 driver and userspace gov in Kernel config.

But if i modprobe cpufreq-cpu0 i don't get any output and the entry
/sys/devices/system/cpu/cpu0/cpufreq is also missing.

Any ideas, what's wrong or missing?

Have you registered cpufreq-cpu0 inside arch/arm/mach-mxs/mach-mxs.c?

Take a look at this patch for an example:
http://www.spinics.net/lists/arm-kernel/msg363761.html