Re: [PATCH v2 0/9] regulator: pwm-regulator: Introduce continuous-mode

Boris Brezillon
2015-07-09T06:30:49Z

Hi Lee,

I'm interested in this feature (so as Doug is), could you add us in Cc
of your next submission ?

On Tue, 7 Jul 2015 16:06:44 +0100
Lee Jones <lee.jones@linaro.org> wrote:

> This patch-set has been rebased on to topic/pwm.
>
> Continuous mode uses the PWM regulator's maximum and minimum supplied
> voltages specified in the regulator-{min,max}-microvolt properties to
> calculate appropriate duty-cycle values. This allows for a much more
> fine grained solution when compared with voltage-table mode, which
> this driver already supports. This solution does make an assumption
> that a %50 duty-cycle value will cause the regulator voltage to run
> at half way between the supplied max_uV and min_uV values.

Well, I'm not sure this assumption works for all pwm driven regulators.
What if your regulator does not react linearly to the PWM duty-cycle
config ?

How about addressing that by using all the entries of the
voltage<->duty table association and doing the linear interpolation
between the provided points instead of doing it on the min -> max
range ?

Best Regards,

Boris

>
> Lee Jones (9):
> ARM: multi_v7_defconfig: Enable ST's PWM driver
> ARM: multi_v7_defconfig: Enable ST's Power Reset driver
> ARM: multi_v7_defconfig: Enable support for PWM Regulators
> ARM: STi: STiH407: Move PWM nodes STiH407 => STiH407-family
> ARM: STi: STiH407: Add PWM Regulator node
> regulator: pwm-regulator: Re-write bindings
> regulator: pwm-regulator: Add support for continuous-voltage
> regulator: pwm-regulator: Simplify voltage to duty-cycle call
> regulator: pwm-regulator: Don't assign structure attributes right away
>
> .../bindings/regulator/pwm-regulator.txt | 68 ++++++++++---
> arch/arm/boot/dts/stih407-family.dtsi | 41 ++++++++
> arch/arm/boot/dts/stih407.dtsi | 28 ------
> arch/arm/configs/multi_v7_defconfig | 3 +
> drivers/regulator/pwm-regulator.c | 109 ++++++++++++++++++---
> 5 files changed, 198 insertions(+), 51 deletions(-)
>

--
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering