From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laxman Dewangan Subject: Re: [PATCH V4 1/5] DT: mfd: add device-tree binding doc fro PMIC max77620/max20024 Date: Mon, 25 Jan 2016 20:38:53 +0530 Message-ID: <56A63A85.6060609@nvidia.com> References: <1453198783-28383-1-git-send-email-ldewangan@nvidia.com> <1453198783-28383-2-git-send-email-ldewangan@nvidia.com> <20160125115610.GC3368@x1> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20160125115610.GC3368@x1> Sender: linux-gpio-owner@vger.kernel.org To: Lee Jones Cc: robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linus.walleij@linaro.org, gnurou@gmail.com, broonie@kernel.org, a.zummo@towertech.it, alexandre.belloni@free-electrons.com, lgirdwood@gmail.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, rtc-linux@googlegroups.com, swarren@nvidia.com, treding@nvidia.com, k.kozlowski@samsung.com, vreddytalla@nvidia.com List-Id: devicetree@vger.kernel.org Thanks Lee for your review. I will take care of most of comment on my=20 next patch. I have reply on some comment and seeking more details for few comments=20 as follows. On Monday 25 January 2016 05:26 PM, Lee Jones wrote: > On Tue, 19 Jan 2016, Laxman Dewangan wrote: > >> +- interrupt-controller: MAX77620 has internal interrupt controller = which >> + takes the interrupt request from internal sub-blocks like RTC, >> + regulators, GPIOs as well as external input. > This is how interrupt-controllers usually work. I don't think there > is any need to explain this. I'd just link to > ../interrupt-controller/interrupts.txt instead. Something similar to (just to confirm) - interrupt-controller: describes the 88pm860x as an interrupt=20 controller (has its own domain) > >> +- #interrupt-cells: Should be set to 2 for IRQ number and flags. >> + The first cell is the IRQ number. IRQ numbers for different inter= rupt >> + source of MAX77620 are defined at dt-bindings/mfd/max77620.h >> + The second cell is the flags, encoded as the trigger masks from b= inding >> + document interrupts.txt, using dt-bindings/irq. > This is a very lengthy read for such little information. Please make > it more succinct. Take a look at other files for examples. I started with as3722.txt and it seems I am carrying forward the=20 complexity here. Originally, as3722 is posted by me only. Any good file= =20 example which I can refer? > Also, > tell use where interrupts.txt is > i.e. ../interrupt-controller/interrupts.txt. > > These are so much easier to read if you tab out from the property nam= e > to the description. > > - reg: I2C device address. > - interrupt-controller: MAX77620 has internal interrupt controller w= hich > takes the interrupt request from internal > sub-blocks like RTC, regulators, GPIOs as well > as external input. > - #interrupt-cells: Should be set to 2 for IRQ number and flags. > The first cell is the IRQ number. IRQ numbers > for different interrupt source of MAX77620 are > defined at dt-bindings/mfd/max77620.h > The second cell is the flags, encoded as the > trigger masks from binding document > interrupts.txt, using dt-bindings/irq. > > ... don't you think? Agree, I can make indenting. And will do whatever places it needs in=20 this document. > >> +Optional properties: >> +------------------- >> +This device also supports the power OFF of system. > What is the "power OFF of system"? PMIC supplies the power. So once PMIC is in OFF state, it turns off all= =20 its rail and hence no SW execution on system. Still external supply wil= l=20 keep supply to PMIC. > >> +Following properties are used for this purpose: >> +- system-power-controller: Boolean, This device will be use as > You don't describe the type of each property, so why is this one > special? Hmm. I describe the boolean and tristate only. Do I need to define type= =20 for integer,string also? >> +power OFF slot and slot period of the device. Device has 3 FPS as F= PS0, >> +FPS1 and FPS2. The details of FPS configuration is provided through >> +subnode "fps". The details of FPS0, FPS1, FPS2 are provided through= the >> +child node under this subnodes. The FPS number is provided via reg = property. >> + >> +The property for fps child nodes as: >> +Required properties: >> + -reg: FPS number like 0, 1, 2 for FPS0, FPS1 and FPS2 respectively= =2E > I'm surprised Rob Acked this. We don't usually do device numbers in = DT. What is best way to make the child node for FPS and differentiate FPS0,= 1, 2? What is your suggestion here? >> + -maxim,active-fps-time-period-us: Active state FPS time period in >> + microseconds. >> + -maxim,suspend-fps-time-period-us: Suspend state FPS time period i= n >> + microseconds. >> + -maxim,fps-enable-input: FPS enable source like EN0, EN1 or SW. Th= e >> + macros are defined on dt-bindings/mfd/max77620.h for >> + different enable source. >> + FPS_EN_SRC_EN0 for EN0 enable source. >> + FPS_EN_SRC_EN1 for En1 enable source. >> + FPS_EN_SRC_SW for SW based control. >> + -maxim,fps-sw-enable: Boolean, applicable if enable input is SW. >> + If this property present then enable the FPS else > "property is present" > > If this enables/disables FPS, why does it matter if it's SW or not? > Why can't you just cal it maxim,fps-enable? Also, is there a case > where you would supply this sub-node, have FPS enabled and this > property not present? If not, can't you just remove the entire node? > Or am I missing something? Here, my need is to connect different FPS source inputs EN0, EN1 or SW.= =20 They can connected to any inputs. That's why fps-enable-input select th= e=20 related digital input for given FPS. However, I can reduce the need of "fps-sw-enable" and make this always=20 enable if fps-enable-input=3D . Here is excerpt from datasheet: B3:B1: SRCFPSx[1:0] Enable Source. Specifies the enable source for the sequencer. 0b00=3DEN0 hardware input 0b01=3DEN1 hardware input 0b10=3DENFPSx software bit 0b11=3Dreserved B0 ENFPSx Software Enable 0=3DDisable FPSx 1=3DEnable FPSx X=3DENFPSx is a don=C2=92t care if SRCFPSx[1:0] !=3D 0b10 > >> + -maxim,enable-global-lpm: Boolean, enable global LPM when the exte= rnal > LPM? Low Power Mode (LPM). I will add details. > +Pinmux and GPIO: > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > I think this whole section needs moving to ../pinctrl and needs to be > reviewed by Linus W. Is this mean I need to create DT binding doc for the each subsystem=20 differently? Actually during AS3722, I had different understanding to have single fi= le. -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html