[v3,0/4] Add driver for Mediatek-based GNSS receivers

Commit Message

Loys Ollivier Jan. 28, 2019, 4:37 p.m. UTC

Hi,

This patch series adds a new GNSS driver for the Mediatek-based GNSS receivers.
These receivers transmits NMEA output sequence after boot.
Power management can be done via the main supply and optional backup supply
as defined in the device tree.

The driver has been tested using a GlobalTop pa6h chipset on a Libretech-cc
board using the expansion header. Changes made in the board device tree can
be found below for reference and testing.

Loys

Version 3 changes:
- driver: Removed "mediatek,mt3339" compatible
- driver: moved gnss_types_names string diff in the GNSS_TYPE patch
- driver: edited [patch 3/4] commit message to remove ref to vendor protocol
- driver: retained the original copyright
- dt: removed interfaces that are not available on the globaltop SoC
- dt: Added missing pins documentation
- dt: added optional properties pin names

Version 2 changes:
- driver: Renamed driver from Globaltop/gtop to Mediatek/mtk
- driver: Added "mediatek,mt3339" compatible
- dt: Renamed bindings from Globaltop to Mediatek
- dt: Moved the current-speed property as optional
- dt: removed the status line in example
- cover-letter: removed the alias that is not needed anymore

Loys Ollivier (4):
  dt-bindings: Add vendor prefix for "GlobalTop Technology, Inc."
  dt-bindings: gnss: add mediatek binding
  gnss: add mtk receiver type support
  gnss: add driver for mediatek receivers

 .../devicetree/bindings/gnss/mediatek.txt          |  37 +++++
 .../devicetree/bindings/vendor-prefixes.txt        |   1 +
 drivers/gnss/Kconfig                               |  13 ++
 drivers/gnss/Makefile                              |   3 +
 drivers/gnss/core.c                                |   1 +
 drivers/gnss/mtk.c                                 | 152 +++++++++++++++++++++
 include/linux/gnss.h                               |   1 +
 7 files changed, 208 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gnss/mediatek.txt
 create mode 100644 drivers/gnss/mtk.c

---
        pinctrl-names = "default";
 };
 
+/* This is brought out on the UART_A_TX (8) and UART_A_RX (10) pins: */
+&uart_A {
+       status = "okay";
+       pinctrl-0 = <&uart_a_pins>;
+       pinctrl-names = "default";
+
+       gnss {
+               compatible = "globaltop,pa6h";
+               v-bckp-supply = <&vcc_3v3>;
+               vcc-supply = <&vcc_3v3>;
+               current-speed = <9600>;
+       };
+};
+
 &usb0 {
        status = "okay";
 };

Patch

diff --git a/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts b/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts
index 90a56af967a7..3b3d4dcc47aa 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts
+++ b/arch/arm64/boot/dts/amlogic/meson-gxl-s905x-libretech-cc.dts
@@ -17,6 +17,7 @@ 
 
        aliases {
                serial0 = &uart_AO;
                ethernet0 = &ethmac;
        };
 
@@ -269,7 +270,20 @@