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Re: [PATCH 1/2] ARM: multi_v7_defconfig: enable CONFIG_PWM_ROCKCHIP=y

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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

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[PATCH 1/2] ARM: multi_v7_defconfig: enable CONFIG_PWM_ROCKCHIP=y Andy Yan <andy.yan@kernel-upstream.org> - 2016-03-12 14:40 +0100
  [PATCH 2/2] ARM: multi_v7_defconfig: enable CONFIG_REGULATOR_PWM=y Andy Yan <andy.yan@kernel-upstream.org> - 2016-03-12 14:40 +0100
    Re: [PATCH 2/2] ARM: multi_v7_defconfig: enable  CONFIG_REGULATOR_PWM=y Thierry Reding <treding@nvidia.com> - 2016-03-14 13:30 +0100
  Re: [PATCH 1/2] ARM: multi_v7_defconfig: enable CONFIG_PWM_ROCKCHIP=y Thierry Reding <treding@nvidia.com> - 2016-03-14 13:20 +0100

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