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References: <20220707080600.49041-1-allen.chen@ite.com.tw> <20220707080600.49041-2-allen.chen@ite.com.tw>
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From:   Robert Foss <robert.foss@linaro.org>
Date:   Tue, 12 Jul 2022 10:07:41 +0200
Message-ID: <CAG3jFystTA3sD2nWJHPYq39WxRwjVt4qj2DMDk2Khh1kR=8ntg@mail.gmail.com>
Subject: Re: [PATCH 1/3] drm/bridge: it6505: Modified power sequence
To:     allen <allen.chen@ite.com.tw>
Cc:     Pin-yen Lin <treapking@google.com>,
        Jau-Chih Tseng <Jau-Chih.Tseng@ite.com.tw>,
        Kenneth Hung <Kenneth.Hung@ite.com.tw>,
        Hermes Wu <Hermes.Wu@ite.com.tw>,
        Pin-Yen Lin <treapking@chromium.org>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        "open list:DRM DRIVERS" <dri-devel@lists.freedesktop.org>,
        open list <linux-kernel@vger.kernel.org>
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Hi Allen,

On Thu, 7 Jul 2022 at 10:06, allen <allen.chen@ite.com.tw> wrote:
>
> From: allen chen <allen.chen@ite.com.tw>
>
> Change power sequence to meet it6505 data sheet requirement when boot on.
>
> Signed-off-by: Pin-Yen Lin <treapking@chromium.org>
> Signed-off-by: Allen Chen <allen.chen@ite.com.tw>
>
> ---
>  drivers/gpu/drm/bridge/ite-it6505.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
> index 2d119e3016b3..aa5e0aa1af85 100644
> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> @@ -3029,7 +3029,7 @@ static int it6505_init_pdata(struct it6505 *it6505)
>                 return PTR_ERR(pdata->ovdd);
>         }
>
> -       pdata->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
> +       pdata->gpiod_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);

Making this change is problematic since it requires a corresponding
change in all of the device trees that use this device. It's against
policy to change this interface after it has been introduced.

Unless anyone thinks otherwise, I would like to see this patch dropped.

>         if (IS_ERR(pdata->gpiod_reset)) {
>                 dev_err(dev, "gpiod_reset gpio not found");
>                 return PTR_ERR(pdata->gpiod_reset);
> --
> 2.25.1
>