From mboxrd@z Thu Jan 1 00:00:00 1970 From: Loys Ollivier Subject: Re: [PATCH v2 2/4] dt-bindings: gnss: add mediatek binding Date: Mon, 28 Jan 2019 16:46:53 +0100 Message-ID: <867eeo7pjm.fsf@baylibre.com> References: <1547744074-28308-1-git-send-email-lollivier@baylibre.com> <1547744074-28308-3-git-send-email-lollivier@baylibre.com> <20190125090755.GB3691@localhost> Mime-Version: 1.0 Content-Type: text/plain; format=flowed Return-path: In-reply-to: <20190125090755.GB3691@localhost> Sender: linux-kernel-owner@vger.kernel.org To: Johan Hovold Cc: Loys Ollivier , devicetree@vger.kernel.org, Rob Herring , Mark Rutland , linux-kernel@vger.kernel.org, Kevin Hilman , linux-amlogic@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Martin Blumenstingl List-Id: linux-mediatek@lists.infradead.org On Fri 25 Jan 2019 at 09:07, Johan Hovold wrote: > On Thu, Jan 17, 2019 at 05:54:32PM +0100, Loys Ollivier wrote: >> Add binding for Mediatek-based GNSS receivers. >> >> Signed-off-by: Loys Ollivier >> --- >> >> 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 | 39 >> ++++++++++++++++++++++ >> 1 file changed, 39 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..fd984b4a9a6d >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/gnss/mediatek.txt >> @@ -0,0 +1,39 @@ >> +Mediatek-based GNSS Receiver DT binding >> + >> +Mediatek chipsets are used in GNSS-receiver modules produced by several >> +vendors and can use UART, SPI or I2C interfaces. >> + >> +Please see Documentation/devicetree/bindings/gnss/gnss.txt for generic >> +properties. >> + >> +Required properties: >> + >> +- compatible : Must be one of >> + >> + "globaltop,pa6h" >> + "mediatek,mt3339" > > I'm not sure it makes sense to add the GPS chip itself as it cannot be > used stand-alone AFAIU, and either not way would require a lot more > resources to be defined than what you add to this binding. > OK, I find it a bit confusing to have Mediatek bindings but no compatible Mediatek SoCs. But it is true that it can't be used stand-alone. I will remove this reference and also remove it from the mtk.c driver code from this patch serie. >> + >> +- vcc-supply : Main voltage regulator (pin name: 3V3_IN, VCC, VDD) > > The pin names in parenthesis were copied from the sirf-star binding and > were used to capture the various names given to this supply by different > vendors. Please drop as it doesn't apply here. > >> + >> +Required properties (I2C): >> +- reg : I2C slave address >> + >> +Required properties (SPI): >> +- reg : SPI chip select address > > While the mt3339 appears to support these interfaces, the globaltop one > does not. > > Have you looked around for a small sample of mt3339-based receivers, to > see whether anyone actually provides these? > Again I'm confused by the fact that it is the Mediatek bindings. Hence why I have added it and why it was not present in the v1 that was only for Globaltop. I find it odd mentionning the chipset but not all its interfaces. I will remove these sections and only list supported interfaces (i.e. UART). Other interfaces can be added afterward if one finds a board that provides them. >> +Optional properties: >> + >> +- timepulse-gpios : Time pulse GPIO >> +- v-bckp-supply : Backup voltage regulator >> +- current-speed : Default UART baud rate > > Looks like you forgot the optional NRESET input and 3D-FIX output (even > if the latter might be of limited use). > Thanks I will clean this section. >> + >> +Example: >> + >> +serial@1234 { >> + compatible = "ns16550a"; >> + >> + gnss { >> + compatible = "globaltop,pa6h"; >> + vcc-supply = <&vcc_3v3>; >> + }; >> +}; > > Johan -- -L