Re: [PATCH 14/15] ARM: dts: sunxi: Enable Broadcom-based Bluetooth for multiple boards

[Chen-Yu Tsai <wens@csie.org>]

On Thu, Nov 8, 2018 at 4:24 PM Maxime Ripard <maxime.ripard@bootlin.com> wrote:
>
> On Wed, Nov 07, 2018 at 06:13:07PM +0800, Chen-Yu Tsai wrote:
> > This patch adds the Bluetooth node, and the underlying UART node if it's
> > missing, to the board device tree file for several boards. The LPO clock
> > is also added to the WiFi side's power sequencing node if it's missing,
> > to correctly represent the shared connections. There is also a PCM
> > connection for Bluetooth, but this is not covered in this patch.
> >
> > These boards all have a WiFi+BT module from AMPAK, which contains one or
> > two Broadcom chips, depending on the model. The older AP6210 contains
> > two, while the newer AP6212 and AP6330 contain just one, as they use
> > two-in-one combo chips.
> >
> > The Bluetooth side of the module is always connected to a UART on the
> > same pingroup as the SDIO pins for the WiFi side, in a 4 wire
> > configuration. Power to the VBAT and VDDIO pins are provided either by
> > the PMIC, using one or several of its regulator outputs, or other fixed
> > regulators on the board. The VBAT and VDDIO pins are shared with the
> > WiFi side, which would correspond to vmmc-supply and vqmmc-supply in the
> > mmc host node. A clock output from the SoC or the external X-Powers RTC
> > provides the LPO low power clock at 32.768 kHz.
> >
> > All the boards covered in this patch are ones that do not require extra
> > changes to the SoC's dtsi file. For the remaining boards that I have
> > worked on, properties or device nodes for the LPO clock's source are
> > missing.
> >
> > Signed-off-by: Chen-Yu Tsai <wens@csie.org>
> > ---
> >  arch/arm/boot/dts/sun7i-a20-cubietruck.dts    | 22 +++++++++++++++++++
> >  arch/arm/boot/dts/sun8i-a83t-bananapi-m3.dts  | 18 +++++++++++++++
> >  .../boot/dts/sun8i-a83t-cubietruck-plus.dts   | 18 +++++++++++++++
> >  arch/arm/boot/dts/sun8i-r16-bananapi-m2m.dts  | 14 ++++++++++++
> >  4 files changed, 72 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
> > index 5649161de1d7..ccbf3b7a062b 100644
> > --- a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
> > +++ b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
> > @@ -103,6 +103,8 @@
> >               pinctrl-names = "default";
> >               pinctrl-0 = <&mmc3_pwrseq_pin_cubietruck>;
> >               reset-gpios = <&pio 7 9 GPIO_ACTIVE_LOW>; /* PH9 WIFI_EN */
> > +             clocks = <&ccu CLK_OUT_A>;
> > +             clock-names = "ext_clock";
> >       };
> >
> >       sound {
> > @@ -246,6 +248,10 @@
> >  };
> >
> >  &pio {
> > +     /* Pin outputs low power clock for WiFi and BT */
> > +     pinctrl-0 = <&clk_out_a_pins_a>;
> > +     pinctrl-names = "default";
> > +
>
> I guess we should make it clear in the comment why it cannot be tied
> to both devices.

I think it's a limitation of the implementation. But it's also a shared output,
so putting it at the source probably makes more sense. So I think it's more like
a preference rather than a hard limitation.

> >       ahci_pwr_pin_cubietruck: ahci_pwr_pin@1 {
> >               pins = "PH12";
> >               function = "gpio_out";
> > @@ -350,6 +356,22 @@
> >       status = "okay";
> >  };
> >
> > +&uart2 {
> > +     pinctrl-names = "default";
> > +     pinctrl-0 = <&uart2_pins_a>;
> > +     status = "okay";
>
> No RTS/CTS?

Missed this one. This was your Cubietruck patch squashed in with the rest.

ChenYu