On Sat, Mar 12, 2016 at 08:50:29PM +0800, Andy Yan wrote:
> All the current rk3066 based boards use pwm modulate vdd_logic
> voltage, the board may hang when the system boot and run to a higher
> frequency without pwm enabled, so enable it as builtin.

I don't understand the rationale here. Surely if the system can't safely
switch to a higher frequency because the regulator isn't available, then
it should be prevented from switching, shouldn't it?

Making this change alone will not prevent users from switching this back
to =m on their own. So either you need to add code to prevent a switch
to an unsupported frequency in the absence of the regulator, or you need
to change the PWM_ROCKCHIP Kconfig option to be bool instead, though the
latter is of course a somewhat ugly hack, whereas the former would be a
proper fix.

Thierry