On Mon 11 Feb 2019 at 09:22, Johan Hovold <johan@xxxxxxxxxx> wrote: > On Wed, Jan 30, 2019 at 09:50:16AM -0600, Rob Herring wrote: >> On Mon, Jan 28, 2019 at 05:37:59PM +0100, Loys Ollivier wrote: >> > Add binding for Mediatek-based GNSS receivers. >> > >> > Signed-off-by: Loys Ollivier <lollivier@xxxxxxxxxxxx> >> > --- >> > >> > v3: >> > Removed the I2C and SPI interfaces references. >> > Removed the "mediatek,mt3339" compatible line. >> > Added the optional propertied (reset, fix) >> > Added the pin names for the optional properties. >> > >> > v2: >> > Renamed bindings from Globaltop/gtop to Mediatek/mtk. >> > Moved current-speed as an optional propertie. >> > Removed the status line in the example. >> > Added "mediatek,mt3339" compatible. >> > >> > .../devicetree/bindings/gnss/mediatek.txt | 37 ++++++++++++++++++++++ >> > 1 file changed, 37 insertions(+) >> > create mode 100644 Documentation/devicetree/bindings/gnss/mediatek.txt >> > >> > diff --git a/Documentation/devicetree/bindings/gnss/mediatek.txt b/Documentation/devicetree/bindings/gnss/mediatek.txt >> > new file mode 100644 >> > index 000000000000..00650d81c5c8 >> > --- /dev/null >> > +++ b/Documentation/devicetree/bindings/gnss/mediatek.txt >> > @@ -0,0 +1,37 @@ >> > +Mediatek-based GNSS Receiver DT binding >> > + >> > +Mediatek chipsets are used in GNSS-receiver modules produced by several >> > +vendors and can use an UART interface. > > s/an/a/ > ok >> > + >> > +Please see Documentation/devicetree/bindings/gnss/gnss.txt for generic >> > +properties. >> > + >> > +Required properties: >> > + >> > +- compatible : Must be >> > + >> > + "globaltop,pa6h" >> > + >> > +- vcc-supply : Main voltage regulator (pin name: VCC) >> > + >> > +Optional properties: >> > + >> > +- gtop,reset-gpios : GPIO used to reset the device >> > + (pin name: RESET, NRESET) >> >> reset-gpios is the standard name. >> >> > +- gtop,fix-gpios : GPIO used to determine device position fix state >> > + (pin name: FIX, 3D_FIX) > > I'm thinking we might need a standard name for fix-gpios as well. This > isn't a feature that is globaltop (or mediatek) specific, and other > manufacturers provide similar functionality through pins named UI_FIX, > or even LCKIND (lock indicator). > > The pin is typically used to drive an indicator LED AFAIU, but the > characteristics of the signal varies from device to device (fw to fw), > for example, pulse when no lock and low otherwise, or pulse when a 2d or > 3d-fix is acquired, etc. > Yes most GNSS recevivers provide a similar feature even if behavior of the line differs. > I'm not sure how useful the pulsing would be for software, but someone > might find a use for it in some form. > Well it is useful to know when you start acquiring "valid" positionning data. I'm using this as a trigger to start recording position. > Rob, is this something we want to keep in the binding, and if so, how > about using a generic name such as "gnss-fix-gpios"? > Name "gnss-fix-gpios" sounds good to me. Loys > Johan -- -L
