lkml.org 
[lkml]   [2023]   [Aug]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 5/9] arm64: dts: qcom: sa8775p-ride: move the reset-gpios property of the PHY
    On Mon, Aug 07, 2023 at 09:35:03PM +0200, Bartosz Golaszewski wrote:
    > From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
    >
    > Device-tree bindings for MDIO define per-PHY reset-gpios as well as a
    > global reset-gpios property at the MDIO node level which controlls all

    s/controlls/controls/

    > devices on the bus. The latter is most likely a workaround for the
    > chicken-and-egg problem where we cannot read the ID of the PHY before
    > bringing it out of reset but we cannot bring it out of reset until we've
    > read its ID.
    >
    > I have proposed a solution for this problem in 2020 but it never got
    > upstream. Now we have a workaround in place which allows us to hard-code
    > the PHY id in the compatible property, thus skipping the ID scanning).

    nitpicky, but I think that already existed at that time :D

    >
    > Let's make the device-tree for sa8775p-ride slightly more correct by
    > moving the reset-gpios property to the PHY node with its ID put into the
    > PHY node's compatible.
    >
    > Link: https://lore.kernel.org/all/20200622093744.13685-1-brgl@bgdev.pl/
    > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
    > ---
    > arch/arm64/boot/dts/qcom/sa8775p-ride.dts | 7 +++----
    > 1 file changed, 3 insertions(+), 4 deletions(-)
    >
    > diff --git a/arch/arm64/boot/dts/qcom/sa8775p-ride.dts b/arch/arm64/boot/dts/qcom/sa8775p-ride.dts
    > index 38327aff18b0..1c471278d441 100644
    > --- a/arch/arm64/boot/dts/qcom/sa8775p-ride.dts
    > +++ b/arch/arm64/boot/dts/qcom/sa8775p-ride.dts
    > @@ -279,13 +279,12 @@ mdio {
    > #address-cells = <1>;
    > #size-cells = <0>;
    >
    > - reset-gpios = <&pmm8654au_2_gpios 8 GPIO_ACTIVE_LOW>;
    > - reset-delay-us = <11000>;
    > - reset-post-delay-us = <70000>;
    > -
    > sgmii_phy: phy@8 {
    > + compatible = "ethernet-phy-id0141.0dd4";
    > reg = <0x8>;
    > device_type = "ethernet-phy";
    > + reset-gpios = <&pmm8654au_2_gpios 8 GPIO_ACTIVE_LOW>;
    > + reset-deassert-us = <70000>;

    Doesn't this need reset-assert-us?


    \
     
     \ /
      Last update: 2023-08-07 23:35    [W:7.352 / U:0.684 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site