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    SubjectRe: [PATCH v8 6/8] MIPS: DTS: CI20: Add DT nodes for HDMI setup
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    Hi Geert,

    > Am 24.11.2021 um 17:21 schrieb Geert Uytterhoeven <geert@linux-m68k.org>:
    >
    > Hi Nikolaus,
    >
    > On Wed, Nov 24, 2021 at 5:19 PM H. Nikolaus Schaller <hns@goldelico.com> wrote:
    >>> Am 23.11.2021 um 21:10 schrieb Paul Cercueil <paul@crapouillou.net>:
    >>> Le mar., nov. 23 2021 at 19:13:59 +0100, H. Nikolaus Schaller <hns@goldelico.com> a écrit :
    >>>> + assigned-clock-rates = <48000000>, <0>, <54000000>, <0>, <27000000>;
    >>>> };
    >>>> &tcu {
    >>>> @@ -509,6 +534,19 @@ pins_i2c4: i2c4 {
    >>>> bias-disable;
    >>>> };
    >>>> + pins_hdmi_ddc: hdmi_ddc {
    >>>> + function = "hdmi-ddc";
    >>>> + groups = "hdmi-ddc";
    >>>> + bias-disable;
    >>>> + };
    >>>> +
    >>>> + /* switch to PF25 as gpio driving DDC_SDA low */
    >>>> + pins_hdmi_ddc_unwedge: hdmi_ddc {
    >>>> + function = "hdmi-ddc";
    >>>> + groups = "hdmi-ddc";
    >>>> + bias-disable;
    >>>> + };
    >>>
    >>> Your pins_hdmi_ddc and pins_hdmi_ddc_unwedge are the exact same? You could just use the former and pass it to both pinctrl-0 and pinctrl-1.
    >>
    >> This was forgotten to remove. We do not make use of the unwedge feature because I could not find out how to use pinctrl to switch this to gpio25 and drive it low.
    >
    > Using gpio-hog?

    well, AFAIR it activates the gpio permanently and is a propery of the gpio controller and not of pinmux.
    The driver assumes it can use pinmux state switching to drive the DDC_SDA line low on demand.

    Since it is unlikely that we need it at all (and we have no test case that it works) I think we simply can leave
    this driver feature unused unless we get a test case.

    BR and thanks,
    Nikolaus

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