Re: [PATCH v3 1/2] regulator: pwm: Add support for a fixed delay after duty cycle changes

From: Rob Herring
Date: Fri Sep 02 2016 - 11:11:59 EST


On Tue, Aug 30, 2016 at 09:21:15PM -0700, Douglas Anderson wrote:
> From: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
>
> A change of the duty cycle doesn't necessarily cause an immediate switch
> to the target voltage. On many PWM regulators there is a fixed "settle
> time" (irrespective of the jump size) that we need to wait after an
> upward jump. This change introduces the device tree property
> "settle-time-up-us" which allows us to specify a fixed delay after a
> voltage increase.
>
> We don't add an option of a fixed delay on the way down for now because
> the way down is probably modelled best with a ramp rate, not a fixed
> delay.
>
> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
> Changes in v3:
> - Took out fixed delay for falling transitions
> - Updated description
>
> .../devicetree/bindings/regulator/pwm-regulator.txt | 6 ++++++

Acked-by: Rob Herring <robh@xxxxxxxxxx>

> drivers/regulator/pwm-regulator.c | 19 +++++++++++++++----
> 2 files changed, 21 insertions(+), 4 deletions(-)