[PATCH] arm64: dts: rockchip: fix USB regulator on ROCK64
Lorenz Brun
lorenz at brun.one
Mon Apr 10 09:01:57 PDT 2023
Am Di, 10. Jan 2023 um 22:38:26 +01:00:00 schrieb Lorenz Brun
<lorenz at brun.one>:
> On Tue, Jan 10 2023 at 14:02:47 +01:00:00, Heiko Stübner
> <heiko at sntech.de> wrote:
>> Am Donnerstag, 5. Januar 2023, 01:29:47 CET schrieb Peter Geis:
>>> On Wed, Jan 4, 2023 at 6:55 PM Lorenz Brun <lorenz at brun.one> wrote:
>>> >
>>> >
>>> > On Wed, Jan 4 2023 at 18:46:25 -05:00:00, Peter Geis
>>> > <pgwipeout at gmail.com> wrote:
>>> > > On Wed, Jan 4, 2023 at 3:55 PM Lorenz Brun <lorenz at brun.one>
>>> wrote:
>>> > >>
>>> > >> Currently the ROCK64 device tree specifies two regulators,
>>> > >> vcc_host_5v
>>> > >> and vcc_host1_5v for USB VBUS on the device. Both of those
>>> are
>>> > >> however
>>> > >> specified with RK_PA2 as the GPIO enabling them, causing the
>>> > >> following
>>> > >> error when booting:
>>> > >>
>>> > >> rockchip-pinctrl pinctrl: pin gpio0-2 already requested by
>>> > >> vcc-host-5v-regulator; cannot claim for vcc-host1-5v-regulator
>>> > >> rockchip-pinctrl pinctrl: pin-2 (vcc-host1-5v-regulator)
>>> status
>>> > >> -22
>>> > >> rockchip-pinctrl pinctrl: could not request pin 2
>>> (gpio0-2) from
>>> > >> group usb20-host-drv on device rockchip-pinctrl
>>> > >> reg-fixed-voltage vcc-host1-5v-regulator: Error applying
>>> setting,
>>> > >> reverse things back
>>> > >>
>>> > >> Looking at the schematic, there are in fact three USB
>>> regulators,
>>> > >> vcc_host_5v, vcc_host1_5v and vcc_otg_v5. But the enable
>>> signal for
>>> > >> all
>>> > >> three is driven by Q2604 which is in turn driven by
>>> GPIO_A2/PA2.
>>> > >>
>>> > >> Since these three regulators are not controllable
>>> separately, I
>>> > >> removed
>>> > >> the second one which was causing the error and left a comment
>>> > >> explaining
>>> > >> that this regulator actually controls multiple rails.
>>> > >>
>>> > >> Signed-off-by: Lorenz Brun <lorenz at brun.one>
>>> > >> ---
>>> > >> arch/arm64/boot/dts/rockchip/rk3328-rock64.dts | 14
>>> +++-----------
>>> > >> 1 file changed, 3 insertions(+), 11 deletions(-)
>>> > >>
>>> > >> diff --git a/arch/arm64/boot/dts/rockchip/rk3328-rock64.dts
>>> > >> b/arch/arm64/boot/dts/rockchip/rk3328-rock64.dts
>>> > >> index f69a38f42d2d..bd82bc80444d 100644
>>> > >> --- a/arch/arm64/boot/dts/rockchip/rk3328-rock64.dts
>>> > >> +++ b/arch/arm64/boot/dts/rockchip/rk3328-rock64.dts
>>> > >> @@ -37,6 +37,9 @@ vcc_sd: sdmmc-regulator {
>>> > >> vin-supply = <&vcc_io>;
>>> > >> };
>>> > >>
>>> > >> + // vcc_host_5v also controls the vcc_host1_5v and
>>> > >> vcc_otg_5v rails
>>> > >> + // but there is only one common control signal
>>> > >> (USB20_HOST_DRV) at
>>> > >> + // GPIO_A2
>>> > >> vcc_host_5v: vcc-host-5v-regulator {
>>> > >> compatible = "regulator-fixed";
>>> > >> gpio = <&gpio0 RK_PA2 GPIO_ACTIVE_LOW>;
>>> > >> @@ -48,17 +51,6 @@ vcc_host_5v: vcc-host-5v-regulator {
>>> > >> vin-supply = <&vcc_sys>;
>>> > >> };
>>> > >>
>>> > >> - vcc_host1_5v: vcc_otg_5v: vcc-host1-5v-regulator {
>>> > >> - compatible = "regulator-fixed";
>>> > >> - gpio = <&gpio0 RK_PA2 GPIO_ACTIVE_LOW>;
>>> > >> - pinctrl-names = "default";
>>> > >> - pinctrl-0 = <&usb20_host_drv>;
>>> > >> - regulator-name = "vcc_host1_5v";
>>> > >> - regulator-always-on;
>>> > >> - regulator-boot-on;
>>> > >> - vin-supply = <&vcc_sys>;
>>> > >> - };
>>> > >
>>> > > Fixed-regulator supports multiple regulators sharing a gpio,
>>> the issue
>>> > > is you have the pinctrl assigned multiple times which is not
>>> > > supported. Simply removing the pinctrl from all but one of the
>>> > > regulators will solve this issue.
>>> > Sure, I can just remove the pinctrl. Should I do anything about
>>> the
>>> > fact that there are three USB switches on that GPIO, but only
>>> two of
>>> > them are described as regulators here? Seems a bit inconsistent
>>> to me.
>>>
>>> All hardware *should* be described, though it isn't uncommon to
>>> see a
>>> single fixed-regulator describe several individual switches that
>>> are
>>> all fed from a common source and controlled by the same gpio. If
>>> they
>>> are not fed by a common source (for example, the otg port is often
>>> fed
>>> from a separate regulator), they must be modeled separately.
>>
>> Which is essentially what Lorenz' patch already did - moving the 3
>> switches
>> into one regulator. So it essentially comes down to where does the
>> not-yet
>> modeled otg-regulator get its current from - also vcc_sys?
>>
> Yeah, all regulators (they are just USB load/overload switches) are
> powered from VCC_SYS, there aren't that many power rails on the
> ROCK64.
>
> The alternative to my first patch would essentially be this:
>
> --- a/arch/arm64/boot/dts/rockchip/rk3328-rock64.dts
> +++ b/arch/arm64/boot/dts/rockchip/rk3328-rock64.dts
> @@ -48,11 +48,18 @@ vcc_host_5v: vcc-host-5v-regulator {
> vin-supply = <&vcc_sys>;
> };
>
> - vcc_host1_5v: vcc_otg_5v: vcc-host1-5v-regulator {
> + vcc_host1_5v: vcc-host1-5v-regulator {
> + compatible = "regulator-fixed";
> + gpio = <&gpio0 RK_PA2 GPIO_ACTIVE_LOW>;
> + regulator-name = "vcc_host1_5v";
> + regulator-always-on;
> + regulator-boot-on;
> + vin-supply = <&vcc_sys>;
> + };
> +
> + vcc_otg_5v: vcc-otg-5v-regulator {
> compatible = "regulator-fixed";
> gpio = <&gpio0 RK_PA2 GPIO_ACTIVE_LOW>;
> - pinctrl-names = "default";
> - pinctrl-0 = <&usb20_host_drv>;
> regulator-name = "vcc_host1_5v";
> regulator-always-on;
> regulator-boot-on;
>
> This drops the pinctrl from all but the first regulator (which is a
> bit weird, the first one is not really special) and then describes
> three separate regulators driven by PA2.
>
> I have no real preference, the one-regulator solution has the
> downside of not accurately describing the three separate load
> switches, the three-regulator solution has the downside of the
> pinctrl definitions being weird.
>
> Regards,
> Lorenz
I never got a response to this, I am fine with both approaches but
would prefer if one of them goes in so I no longer have this error on
every boot. If the approach above with three regulators is chosen I can
send out a proper patch.
Regards,
Lorenz
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