On Wed, Jun 21, 2023 at 10:52:28AM +0100, Andre Przywara wrote:
> On Tue, 20 Jun 2023 15:00:22 -0500
> Chris Morgan <macroalpha82@xxxxxxxxx> wrote:
>
> Hi Chris,
>
> thanks for sending this!
> Is there some schematics for this somewhere? Or was this based on
> information gathered from the stock firmware?
>
> > From: Chris Morgan <macromorgan@xxxxxxxxxxx>
> >
> > The Anbernic RG-Nano is a small portable game device based on the
> > Allwinner V3s SoC. It has GPIO buttons on the face and side for
> > input, a single mono speaker, a 240x240 SPI controlled display,
> > and a USB-C OTG port for power. The SoC includes 64MB of RAM and
> > an SD card slot for booting.
> >
> > The SPI display is currently unsupported, as it will either require
> > a new tinydrm driver or changes to the staging fbtft driver to support.
> > I plan on working on a tinydrm driver to properly support it. There
> > also may be a missing mux in the audio path that must be discovered and
> > defined before audio will be fully working (internal speaker does not
> > work yet, external headphones untested).
> >
> > Working:
> > - SDMMC
> > - Buttons
> > - Charging/battery/PMIC
> >
> > Not working:
> > - Display
> > - Audio
> >
> > Signed-off-by: Chris Morgan <macromorgan@xxxxxxxxxxx>
> > ---
> > arch/arm/boot/dts/Makefile | 1 +
> > .../boot/dts/sun8i-v3s-anbernic-rg-nano.dts | 209 ++++++++++++++++++
> > 2 files changed, 210 insertions(+)
> > create mode 100644 arch/arm/boot/dts/sun8i-v3s-anbernic-rg-nano.dts
> >
> > diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
> > index 59829fc90315..31418b594222 100644
> > --- a/arch/arm/boot/dts/Makefile
> > +++ b/arch/arm/boot/dts/Makefile
> > @@ -1414,6 +1414,7 @@ dtb-$(CONFIG_MACH_SUN8I) += \
> > sun8i-t113s-mangopi-mq-r-t113.dtb \
> > sun8i-t3-cqa3t-bv3.dtb \
> > sun8i-v3-sl631-imx179.dtb \
> > + sun8i-v3s-anbernic-rg-nano.dtb \
> > sun8i-v3s-licheepi-zero.dtb \
> > sun8i-v3s-licheepi-zero-dock.dtb \
> > sun8i-v40-bananapi-m2-berry.dtb
> > diff --git a/arch/arm/boot/dts/sun8i-v3s-anbernic-rg-nano.dts b/arch/arm/boot/dts/sun8i-v3s-anbernic-rg-nano.dts
> > new file mode 100644
> > index 000000000000..ead315e8fc38
> > --- /dev/null
> > +++ b/arch/arm/boot/dts/sun8i-v3s-anbernic-rg-nano.dts
> > @@ -0,0 +1,209 @@
> > +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> > +
> > +/dts-v1/;
> > +#include <dt-bindings/input/linux-event-codes.h>
> > +#include "sun8i-v3s.dtsi"
> > +#include "sunxi-common-regulators.dtsi"
> > +
> > +/ {
> > + model = "Anbernic RG Nano";
> > + compatible = "anbernic,rg-nano", "allwinner,sun8i-v3s";
> > +
> > + aliases {
> > + serial0 = &uart0;
>
> Is that serial console actually usable, so are there pins or pads on the
> PCB? Have you opened it up?
>
There are tx and rx pads exposed, and about a cm away a gnd pad also
exposed. Sadly I ripped the solder pad off of mine, so remaining
debugging is going on via ssh over USB gadget mode.
> > + };
> > +
> > + backlight: backlight {
> > + compatible = "pwm-backlight";
> > + pwms = <&pwm 0 40000 1>;
> > + brightness-levels = <0 1 2 3 8 14 21 32 46 60 80 100>;
> > + default-brightness-level = <11>;
> > + power-supply = <®_vcc5v0>;
> > + };
> > +
> > + chosen {
> > + stdout-path = "serial0:115200n8";
> > + };
> > +
> > + gpio_keys: gpio-keys {
> > + compatible = "gpio-keys";
> > +
> > + button-a {
> > + gpios = <&gpio_expander 12 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-A";
> > + linux,code = <BTN_EAST>;
> > + };
> > +
> > + button-b {
> > + gpios = <&gpio_expander 14 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-B";
> > + linux,code = <BTN_SOUTH>;
> > + };
> > +
> > + button-down {
> > + gpios = <&gpio_expander 1 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "DPAD-DOWN";
> > + linux,code = <BTN_DPAD_DOWN>;
> > + };
> > +
> > + button-left {
> > + gpios = <&gpio_expander 4 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "DPAD-LEFT";
> > + linux,code = <BTN_DPAD_LEFT>;
> > + };
> > +
> > + button-right {
> > + gpios = <&gpio_expander 0 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "DPAD-RIGHT";
> > + linux,code = <BTN_DPAD_RIGHT>;
> > + };
> > +
> > + button-se {
> > + gpios = <&gpio_expander 7 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-SELECT";
> > + linux,code = <BTN_SELECT>;
> > + };
> > +
> > + button-st {
> > + gpios = <&gpio_expander 6 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-START";
> > + linux,code = <BTN_START>;
> > + };
> > +
> > + button-tl {
> > + gpios = <&gpio_expander 2 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-L";
> > + linux,code = <BTN_TL>;
> > + };
> > +
> > + button-tr {
> > + gpios = <&gpio_expander 15 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-R";
> > + linux,code = <BTN_TR>;
> > + };
> > +
> > + button-up {
> > + gpios = <&gpio_expander 3 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "DPAD-UP";
> > + linux,code = <BTN_DPAD_UP>;
> > + };
> > +
> > + button-x {
> > + gpios = <&gpio_expander 11 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-X";
> > + linux,code = <BTN_NORTH>;
> > + };
> > +
> > + button-y {
> > + gpios = <&gpio_expander 13 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
> > + label = "BTN-Y";
> > + linux,code = <BTN_WEST>;
> > + };
> > + };
> > +};
> > +
> > +&codec {
> > + allwinner,audio-routing = "Headphone", "HP",
> > + "Headphone", "HPCOM",
> > + "MIC1", "Mic",
> > + "Mic", "HBIAS";
> > + status = "okay";
> > +};
> > +
> > +&i2c0 {
> > + status = "okay";
> > +
> > + gpio_expander: gpio@20 {
> > + compatible = "nxp,pcal6416";
> > + reg = <0x20>;
> > + gpio-controller;
> > + #gpio-cells = <2>;
> > + #interrupt-cells = <2>;
> > + interrupt-controller;
> > + interrupt-parent = <&pio>;
> > + interrupts = <1 3 IRQ_TYPE_EDGE_BOTH>;
> > + };
> > +
> > + axp209: pmic@34 {
> > + reg = <0x34>;
> > + interrupt-parent = <&pio>;
> > + interrupts = <1 5 IRQ_TYPE_EDGE_FALLING>;
> > + };
> > +
> > + pcf8563: rtc@51 {
> > + compatible = "nxp,pcf8563";
> > + reg = <0x51>;
> > + };
> > +};
> > +
> > +#include "axp209.dtsi"
> > +
> > +&ac_power_supply {
> > + status = "okay";
> > +};
> > +
> > +&battery_power_supply {
> > + status = "okay";
> > +};
> > +
> > +&mmc0 {
> > + broken-cd;
> > + bus-width = <4>;
> > + disable-wp;
> > + vmmc-supply = <®_vcc3v3>;
> > + vqmmc-supply = <®_vcc3v3>;
> > + status = "okay";
> > +};
> > +
> > +&pwm {
> > + status = "okay";
> > +};
> > +
> > +®_dcdc2 {
> > + regulator-always-on;
> > + regulator-max-microvolt = <1400000>;
> > + regulator-min-microvolt = <1000000>;
>
> I think since it's not referenced anywhere, and it's always-on, it should
> be just a single voltage, so the same value for both min and max. I guess
> at least this voltage here needs to be fixed anyway, and it wouldn't
> really work with a different value? Does the bootloader set something up
> there, or is it the default value that's just kept?
It's always on at 1.25v according to the schematic. I also plan to move
this devicetree to mainline U-Boot, so best to get it right here and
there. Do you think just setting 1250000 for min and max works then?
>
> > + regulator-name = "vdd-cpu-sys-ephy";
> > +};
> > +
> > +®_dcdc3 {
> > + regulator-always-on;
> > + regulator-max-microvolt = <3450000>;
> > + regulator-min-microvolt = <3000000>;
>
> Same here, I guess: a single voltage.
> If in doubt, you could pick the current voltage from
> /sys/kernel/debug/regulator/regulator_summary and use that.
This is a fixed 3.3v. Honestly I think this is output for the entire
"3.3v rail" if I'm reading the schematics right.
>
> > + regulator-name = "vcc-io-ephy-mcsi-usb";
> > +};
> > +
> > +®_ldo1 {
> > + regulator-name = "vcc-rtc";
Here's one I could use some advice on actually. The existing driver
has a constraint holding this at 1.3v, however I need to run it at
3.3v since it's hooked up to an external RTC that needs 3.3v. Any
thoughts on how to tell the regulator "always be 1.3v, unless a
voltage is explicitly specified")?
> > +};
> > +
> > +®_ldo2 {
> > + regulator-always-on;
> > + regulator-max-microvolt = <3300000>;
> > + regulator-min-microvolt = <2800000>;
>
> same here.
Fixed 3.0v, again if I'm reading correctly.
>
> > + regulator-name = "avcc-pll";
> > +};
> > +
> > +&spi0 {
> > + status = "okay";
> > +};
> > +
> > +&uart0 {
> > + pinctrl-0 = <&uart0_pb_pins>;
> > + pinctrl-names = "default";
> > + status = "okay";
> > +};
> > +
> > +&usb_otg {
> > + dr_mode = "otg";
> > + status = "okay";
> > +};
> > +
> > +&usb_power_supply {
> > + status = "okay";
> > +};
> > +
> > +&usbphy {
> > + usb0_id_det-gpios = <&pio 5 6 GPIO_ACTIVE_HIGH>;
> > + status = "okay";
>
> So in the commit message you say "USB-C for power", but this here
> describes a full featured USB port. So does that work? Can you use it as a
> gadget, but also as a host?
Yes, it's an OTG port with the ID pin pulled to ground. I have it set
as a peripherial on mine so I can ssh via ethernet gadget (since I
broke my solder pads for serial), but it also acts as a host for the
included "USB audio dongle" which is just a simple USB DAC (and not
using any analog pins).
Also, I noticed that usb0_id_det-gpios is wrong, so I changed it.
>
> Otherwise this looks alright to me.
>
> Cheers,
> Andre
>
>
> > +};
>
