On Fri, Nov 26, 2021 at 8:59 AM Andreas Kemnade <andreas@xxxxxxxxxxxx> wrote: > > On Tue, 23 Nov 2021 23:29:26 +1000 > Alistair Francis <alistair23@xxxxxxxxx> wrote: > > > On Thu, Nov 18, 2021 at 7:40 AM Andreas Kemnade <andreas@xxxxxxxxxxxx> wrote: > > > > > > On Wed, 10 Nov 2021 22:29:41 +1000 > > > Alistair Francis <alistair@xxxxxxxxxxxxx> wrote: > > > > > > > Initial support for the Silergy SY7636A Power Management chip > > > > and regulator. > > > > > > > > Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx> > > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > > > > Acked-for-MFD-by: Lee Jones <lee.jones@xxxxxxxxxx> > > > > --- > > > > .../bindings/mfd/silergy,sy7636a.yaml | 79 +++++++++++++++++++ > > > > 1 file changed, 79 insertions(+) > > > > create mode 100644 Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml > > > > > > > > diff --git a/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml > > > > new file mode 100644 > > > > index 000000000000..0566f9498e2f > > > > --- /dev/null > > > > +++ b/Documentation/devicetree/bindings/mfd/silergy,sy7636a.yaml > > > [...] > > > > + regulators: > > > > + type: object > > > > + > > > > + properties: > > > > + compatible: > > > > + const: silergy,sy7636a-regulator > > > > + > > > > + vcom: > > > > + type: object > > > > + $ref: /schemas/regulator/regulator.yaml# > > > > + properties: > > > > + regulator-name: > > > > + const: vcom > > > > + > > > hmm, this is what? If I understand it correctly, vcom means some > > > voltage for compensation. On other comparable pmics (e.g. TPS65185 > > > which has also a sane public datasheet, MAX17135) I have seen some > > > methods to measure a voltage while the display is doing something > > > defined and then program this voltage non-volatile for compensation > > > during manufacturing. > > > > > > If I understand the code correctly all the bunch of voltages are > > > powered up if this one is enabled. > > > So at least a description should be suitable. > > > > > > The other comparable PMICs have at least regulators named VCOM, DISPLAY > > > (controls several regulators, started with delays configured via > > > registers) and V3P3. MAX17135 source can be found in NXP kernels, > > > TPS65185 in Kobo vendor kernels. > > > > > > So I would expect to see something similar here and a description or at > > > least not such a misleading name as vcom if it is for some reason not > > > feasible to separate the regulators. > > > > This is a vcom in the sense of voltage for compensation. We just > > currently don't support setting the vcom. > > > > I had a look at the Kobo code and this is similar to > > https://github.com/akemnade/linux/blob/kobo/epdc-pmic-5.15/drivers/regulator/sy7636-regulator.c#L614 > > > > So I think that vcom is still the appropriate name for this. > > > seems that you did not get me. If I understand the code behind it > correctly, it turns on all power rails (the +-15V stuff, VEE and so on) > with the defined delays, not just vcom because it sets > SY7636A_OPERATION_MODE_CRL_ONOFF. Controlling VCOM separately is possible > by using SY7636A_OPERATION_MODE_CRL_VCOMCTL in combintion with a > vcom_en gpio. > > I do not see a reason to turn on vcom only without the other higher > voltage rails, so the behaviour is not necessarily wrong but if I read > the binding documentation I would expect that just vcom is turned on. > That is the mismatch I am talking about. Ah! Ok I understand. I'll rename it to vdd then. Alistair > > If we agree on this idea that one regulator is enabling everything, I > would adapt my EPDC drm driver and tps65185 driver (which are both in > my clean up to be upstreamable-queue). > > Just another thing to compare with: > https://github.com/Freescale/linux-fslc/blob/4.1-2.0.x-imx/drivers/regulator/max17135-regulator.c > that seems to be the starting point for kobo vendor kernel epd pmics. > They seem to have taken the source and modified things. There we have > regulators with empty ops for that step-up converted stuff, a separate > vcom and a display regulator which really controls all of these step-up > things. > > Regards, > Andreas
