From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH 8/8] dt: regulator: pwm-regulator: Re-write bindings Date: Fri, 5 Jun 2015 19:47:11 +0100 Message-ID: <20150605184711.GG7058@x1> References: <1433529771-24496-1-git-send-email-lee.jones@linaro.org> <1433529771-24496-9-git-send-email-lee.jones@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <1433529771-24496-9-git-send-email-lee.jones@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: kernel@stlinux.com, broonie@kernel.org, lgirdwood@gmail.com, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Whoops, nearly forgot the DT folks. Sorry chaps. > * Add support for continuous-voltage mode > * Put more meat on the bones with regards to voltage-table mode > * Sort out formatting for ease of consumption >=20 > Signed-off-by: Lee Jones > --- > .../bindings/regulator/pwm-regulator.txt | 66 ++++++++++++= ++++++---- > 1 file changed, 54 insertions(+), 12 deletions(-) >=20 > diff --git a/Documentation/devicetree/bindings/regulator/pwm-regulato= r.txt b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt > index ce91f61..9a8269f 100644 > --- a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt > +++ b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt > @@ -1,27 +1,69 @@ > -pwm regulator bindings > +Bindings for the Generic PWM Regulator > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > + > +Currently supports 2 modes of operation: > + > +voltage-table: When in this mode, a voltage table (See below) of pr= edefined > + voltage <=3D> duty-cycle values must be provided via DT. > + Limitations are that the regulator can only operate at the > + voltages supplied in the table. Intermediary duty-cycle > + values which would normally allow finer grained voltage > + selection are ignored and rendered useless. Although more > + control is given to the user if the assumptions made in > + continuous-voltage mode do not reign true. > + > +continuous-voltage: This mode uses the regulator's maximum and minim= um 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 above. 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. > =20 > Required properties: > -- compatible: Should be "pwm-regulator" > -- pwms: OF device-tree PWM specification (see PWM binding pwm.txt) > -- voltage-table: voltage and duty table, include 2 members in each s= et of > - brackets, first one is voltage(unit: uv), the next is duty(unit: p= ercent) > +-------------------- > +- compatible: Should be "pwm-regulator" > + > +- pwms: PWM specification (See: ../pwm/pwm.txt) > + > +One of these must be provided: > +- voltage-table: Voltage and Duty-Cycle table consisting of 2 cells > + First cell is voltage in microvolts (uV) > + Second cell is duty-cycle in percent (%) > + > +- max-duty-cycle: Maximum Duty-Cycle value -- this will normally be = 255 (0xff) > + for an 8 bit PMU device > =20 > -Any property defined as part of the core regulator binding defined i= n > -regulator.txt can also be used. > +If both are provided, the current default is voltage-table mode. > =20 > -Example: > +Any property defined as part of the core regulator binding can also = be used. > +(See: ../regulator/regulator.txt) > + > +Continuous Voltage Example: > pwm_regulator { > compatible =3D "pwm-regulator; > pwms =3D <&pwm1 0 8448 0>; > + regulator-min-microvolt =3D <1016000>; > + regulator-max-microvolt =3D <1114000>; > + regulator-name =3D "vdd_logic"; > + > + max-duty-cycle =3D <255>; /* 8bit PWM */ > + }; > =20 > +Voltage Table Example: > + pwm_regulator { > + compatible =3D "pwm-regulator; > + pwms =3D <&pwm1 0 8448 0>; > + regulator-min-microvolt =3D <1016000>; > + regulator-max-microvolt =3D <1114000>; > + regulator-name =3D "vdd_logic"; > + > + /* Voltage Duty-Cycle */ > voltage-table =3D <1114000 0>, > <1095000 10>, > <1076000 20>, > <1056000 30>, > <1036000 40>, > <1016000 50>; > - > - regulator-min-microvolt =3D <1016000>; > - regulator-max-microvolt =3D <1114000>; > - regulator-name =3D "vdd_logic"; > }; --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog