[PATCH v2] ARM: dts: sun7i: Add wifi dt node on Banana Pro

[Jörg Krause]

Hi Maxim,

On Thu, 2017-01-05 at 19:11 +0100, Maxime Ripard wrote:
> Hi Jörg,
> 
> On Thu, Jan 05, 2017 at 06:37:53PM +0100, Jörg Krause wrote:
> > The Banana Pro has an AMPAK AP6181 WiFi+Bluetooth module. The WiFi
> > part
> > is a BCM43362 IC connected to MMC3 of the A20 SoC via SDIO. The IC
> > also
> > takes a power enable signal via GPIO.
> > 
> > This commit adds a device-tree node to power it up, so the mmc
> > subsys
> > can scan it, and enables the mmc controller which is connected to
> > it.
> > 
> > As the wifi enable pin of the AP6181 module is not really a
> > regulator,
> > switch the mmc3 node to the mmc-pwrseq framework for controlling
> > it.
> > This more accurately reflectes how the hardware actually works.
> > 
> > Signed-off-by: Jörg Krause <joerg.krause at embedded.rocks>
> > ---
> > Changes v2 (suggested by Maxime Ripard):
> >   - rename pwrseq node to clarify the function rather what it's
> >     connected to
> >   - use dash instead of underscore for the pwrseq node name
> >   - remove setting pull-ups for mmc3 (default since commit
> > 37bc56128d92)
> > 
> > ---
> >  arch/arm/boot/dts/sun7i-a20-bananapro.dts | 30 ++++++++++++++++++-
> > -----------
> >  1 file changed, 18 insertions(+), 12 deletions(-)
> > 
> > diff --git a/arch/arm/boot/dts/sun7i-a20-bananapro.dts
> > b/arch/arm/boot/dts/sun7i-a20-bananapro.dts
> > index 19d63d4049de..77f8fb76c157 100644
> > --- a/arch/arm/boot/dts/sun7i-a20-bananapro.dts
> > +++ b/arch/arm/boot/dts/sun7i-a20-bananapro.dts
> > @@ -76,6 +76,13 @@
> >  		};
> >  	};
> >  
> > +	wifi_pwrseq: wifi-pwrseq {
> > +		compatible = "mmc-pwrseq-simple";
> > +		pinctrl-names = "default";
> > +		pinctrl-0 = <&vmmc3_pin_bananapro>;
> > +		reset-gpios = <&pio 7 22 GPIO_ACTIVE_LOW>;
> > +	};
> > +
> >  	reg_gmac_3v3: gmac-3v3 {
> >  		compatible = "regulator-fixed";
> >  		pinctrl-names = "default";
> > @@ -87,17 +94,6 @@
> >  		enable-active-high;
> >  		gpio = <&pio 7 23 GPIO_ACTIVE_HIGH>;
> >  	};
> > -
> > -	reg_vmmc3: vmmc3 {
> > -		compatible = "regulator-fixed";
> > -		pinctrl-names = "default";
> > -		pinctrl-0 = <&vmmc3_pin_bananapro>;
> > -		regulator-name = "vmmc3";
> > -		regulator-min-microvolt = <3300000>;
> > -		regulator-max-microvolt = <3300000>;
> > -		enable-active-high;
> > -		gpio = <&pio 7 22 GPIO_ACTIVE_HIGH>;
> > -	};
> >  };
> >  
> >  &ahci {
> > @@ -166,10 +162,20 @@
> >  &mmc3 {
> >  	pinctrl-names = "default";
> >  	pinctrl-0 = <&mmc3_pins_a>;
> > -	vmmc-supply = <&reg_vmmc3>;
> > +	vmmc-supply = <&reg_vcc3v3>;
> > +	mmc-pwrseq = <&wifi_pwrseq>;
> >  	bus-width = <4>;
> >  	non-removable;
> > +	wakeup-source;
> 
> Sorry for not spotting that earlier, but this is suspicious. The PIO
> is not able to be wake up the CPU, since it's connected to the GIC
> that is shut down during CPU suspend. Our only wake up source is the
> NMI controller. So either it is not able to wake up the system, or
> the
> interrupt line in not the right one.

Sorry, but I'm not sure I understand...

The "WIFI-HOST-WAKE" line connects "WL_HOST_WAKE" of the AP6210 to pin
EINT15 of the A20 as shown in the schematic of the board [1].

Note, that this is the same hardware configuration as done on the
Banana Pi M1+ [2]. The device tree node for mmc3 of the M1+ has
"wakeup-source" enabled, too, so I inherited it. However, I did not
tested the wake-up feature.

[1] http://mirror.lemaker.org/Banana%20Pro%20Schematic.pdf
[2] https://drive.google.com/file/d/0B4PAo2nW2KfnNTk5WnVSV0lPejA/view?u
sp=sharing

Jörg