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 <lollivier@xxxxxxxxxxxx>
> ---
>
> 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.
> +
> +- 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?
> +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).
> +
> +Example:
> +
> +serial@1234 {
> + compatible = "ns16550a";
> +
> + gnss {
> + compatible = "globaltop,pa6h";
> + vcc-supply = <&vcc_3v3>;
> + };
> +};
Johan
