linux-kernel - Re: [PATCH v2 2/2] arm64: dts: qcom: sa8295p: Enable tertiary controller and its 4 USB ports

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Tue, 13 Feb 2024 09:39:51 +0100
From: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To: Krishna Kurapati <quic_kriskura@...cinc.com>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
 Rob Herring <robh+dt@...nel.org>, Bjorn Andersson <andersson@...nel.org>,
 Konrad Dybcio <konrad.dybcio@...aro.org>, Conor Dooley <conor+dt@...nel.org>
Cc: devicetree@...r.kernel.org, linux-arm-msm@...r.kernel.org,
 linux-kernel@...r.kernel.org, quic_ppratap@...cinc.com,
 quic_jackp@...cinc.com
Subject: Re: [PATCH v2 2/2] arm64: dts: qcom: sa8295p: Enable tertiary
 controller and its 4 USB ports

On 13/02/2024 09:27, Krishna Kurapati wrote:
> Multiport USB controller (host-only) of SA8295 ADP has 4 Type-A ports
> exposed for connecting peripherals. The VBUS to these peripherals is
> provided by TPS2559QWDRCTQ1 regulators connected to these ports. Each
> regulator has an enable pin controlled by PMM8540. Since these regulators
> are GPIO controlled regulators, model them as fixed regulators and keep
> them Always-On at boot since we are wakeup capable and we don't need to
> turn them off on suspend. Also since we don't enter device mode, these
> regulators can be kept on.
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@...cinc.com>
> ---
>  arch/arm64/boot/dts/qcom/sa8295p-adp.dts | 83 ++++++++++++++++++++++++
>  1 file changed, 83 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sa8295p-adp.dts b/arch/arm64/boot/dts/qcom/sa8295p-adp.dts
> index fd253942e5e5..49418843c214 100644
> --- a/arch/arm64/boot/dts/qcom/sa8295p-adp.dts
> +++ b/arch/arm64/boot/dts/qcom/sa8295p-adp.dts
> @@ -9,6 +9,7 @@
>  #include <dt-bindings/gpio/gpio.h>
>  #include <dt-bindings/regulator/qcom,rpmh-regulator.h>
>  #include <dt-bindings/spmi/spmi.h>
> +#include <dt-bindings/pinctrl/qcom,pmic-gpio.h>
>  
>  #include "sa8540p.dtsi"
>  #include "sa8540p-pmics.dtsi"
> @@ -108,6 +109,46 @@ edp3_connector_in: endpoint {
>  			};
>  		};
>  	};
> +
> +	regulator-usb2-vbus {
> +		compatible = "regulator-fixed";
> +		regulator-name = "USB2_VBUS";
> +		gpio = <&pmm8540c_gpios 9 GPIO_ACTIVE_HIGH>;
> +		pinctrl-0 = <&usb2_en>;
> +		pinctrl-names = "default";
> +		enable-active-high;
> +		regulator-always-on;
> +	};
> +
> +	regulator-usb3-vbus {
> +		compatible = "regulator-fixed";
> +		regulator-name = "USB3_VBUS";
> +		gpio = <&pmm8540e_gpios 5 GPIO_ACTIVE_HIGH>;
> +		pinctrl-0 = <&usb3_en>;
> +		pinctrl-names = "default";
> +		enable-active-high;
> +		regulator-always-on;
> +	};
> +
> +	regulator-usb4-vbus {
> +		compatible = "regulator-fixed";
> +		regulator-name = "USB4_VBUS";
> +		gpio = <&pmm8540g_gpios 5 GPIO_ACTIVE_HIGH>;
> +		pinctrl-0 = <&usb4_en>;
> +		pinctrl-names = "default";
> +		enable-active-high;
> +		regulator-always-on;
> +	};
> +
> +	regulator-usb5-vbus {
> +		compatible = "regulator-fixed";
> +		regulator-name = "USB5_VBUS";
> +		gpio = <&pmm8540g_gpios 9 GPIO_ACTIVE_HIGH>;
> +		pinctrl-0 = <&usb5_en>;
> +		pinctrl-names = "default";
> +		enable-active-high;
> +		regulator-always-on;

Why all these regulators are always on? If USB controller does not probe
for any reason, why keeping them enabled? These must not be always-on,
but instead used by connector as VBUS supply (or by whatever you have
there for USB).

Best regards,
Krzysztof