From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [PATCH 09/18] arm64: dts: ulcb-kf: enable USB2 PHY of channel 0 Date: Thu, 12 Oct 2017 14:27:01 +0200 Message-ID: References: <1504737267-22829-1-git-send-email-vladimir.barinov@cogentembedded.com> <1504737377-23191-1-git-send-email-vladimir.barinov@cogentembedded.com> <806c5e8e-af85-e73b-a7a4-44ebf82dee7e@cogentembedded.com> <1c5fc090-af98-0041-be8b-b06dc81d4670@cogentembedded.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: linux-renesas-soc-owner@vger.kernel.org To: Yoshihiro Shimoda Cc: batareich batareich , Simon Horman , Magnus Damm , Rob Herring , Mark Rutland , Catalin Marinas , Will Deacon , "devicetree@vger.kernel.org" , Linux-Renesas List-Id: devicetree@vger.kernel.org Hi Shimoda-san, On Thu, Oct 12, 2017 at 1:41 PM, Yoshihiro Shimoda wrote: >> From: Vladimir Barinov, Sent: Saturday, October 7, 2017 2:29 AM >> On 06.10.2017 10:15, Geert Uytterhoeven wrote: >> > CC Shimoda-san >> > >> > On Fri, Oct 6, 2017 at 4:38 AM, Vladimir Barinov >> > wrote: >> >> On 20.09.2017 15:59, Geert Uytterhoeven wrote: >> >>> On Thu, Sep 7, 2017 at 12:36 AM, Vladimir Barinov >> >>> wrote: >> >>>> This supports USB2 PHY channel #0 on ULCB Kingfisher board >> >>>> >> >>>> Signed-off-by: Vladimir Barinov >> >>> Reviewed-by: Geert Uytterhoeven >> >>> >> >>>> index ca8de1a..0854600 100644 >> >>>> --- a/arch/arm64/boot/dts/renesas/ulcb-kf.dtsi >> >>>> +++ b/arch/arm64/boot/dts/renesas/ulcb-kf.dtsi >> >>>> @@ -60,6 +60,11 @@ >> >>>> groups = "scif1_data_b"; >> >>>> function = "scif1"; >> >>>> }; >> >>>> + >> >>>> + usb0_pins: usb0 { >> >>>> + groups = "usb0"; >> >>>> + function = "usb0"; >> >>>> + }; >> >>>> }; >> >>>> >> >>>> &scif1 { >> >>>> @@ -68,3 +73,10 @@ >> >>>> >> >>>> status = "okay"; >> >>>> }; >> >>>> + >> >>>> +&usb2_phy0 { >> >>>> + pinctrl-0 = <&usb0_pins>; >> >>>> + pinctrl-names = "default"; >> >>>> + >> >>> Don't you need >> >>> >> >>> vbus-supply = <&vbus0_usb2>; >> >>> >> >>> with vbus0_usb2 a fixed regulator controlled by GPIO P11 (OTG_EXTLPn) from >> >>> GPIO expander U11 (TCA9539)? >> >>> May be optional, though. salvator-common.dtsi has it. >> >> Yes, I need this gpio. >> >> I need both OTG_EXTLPn and OTG_OFFVBUSn from the same gpio expander. >> >> >> >> I've been considering to use either vbus-supply + gpio hog or use gpio hog >> >> for both of them for consistency. >> >> What do you think about this? >> > For OTG_EXTLPn you don't really need a hog, as it will be controlled by the >> > USB driver/subsystem, like on Salvator-X(S), right? >> Agreed. >> > >> > For OTG_OFFVBUSn, which is (optionally) driven from USB0_PWEN on >> > Salvator-X(S) I don't know if you need a GPIO hog or not. I have to defer your >> > question to Shimoda-san. > > I'm sorry for the delayed response. > I think OTG_OFFVBUSn should be low level to avoid conflict 5V supply from U13's OUT pins. > >> This pin should be tied permanently low to disable internal MAX3355 >> internal VBUS charge pump. > > I agree. OK. >> Hence probably gpio hog is enough for OTG_OFFVBUSn. > > I'm afraid but I don't understand this "gpio hog" means. "gpio hog" is a means to tie a GPIO to a specific level, cfr. Documentation/devicetree/bindings/gpio/gpio.txt. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds