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Message-ID: <64760d6e-10f4-4108-d467-f40289a1c6b4@quicinc.com>
Date:   Mon, 18 Sep 2023 13:27:05 -0700
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Subject: Re: [RFC PATCH v2 4/9] drm/panel: nv3052c: Wait before entering sleep
 mode
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To:     John Watts <contact@jookia.org>, <dri-devel@lists.freedesktop.org>
CC:     Neil Armstrong <neil.armstrong@linaro.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Heiko Stuebner <heiko@sntech.de>,
        Chris Morgan <macromorgan@hotmail.com>,
        Jagan Teki <jagan@edgeble.ai>,
        Paul Cercueil <paul@crapouillou.net>,
        Christophe Branchereau <cbranchereau@gmail.com>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20230918125853.2249187-1-contact@jookia.org>
 <20230918125853.2249187-5-contact@jookia.org>
From:   Jessica Zhang <quic_jesszhan@quicinc.com>
In-Reply-To: <20230918125853.2249187-5-contact@jookia.org>
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On 9/18/2023 5:58 AM, John Watts wrote:
> The panel needs us to wait 120ms between exiting and entering sleep.
> Guarantee that by always waiting 150ms before entering sleep mode.

Hi John,

Same question as the last patch -- is this a fix for something?

Thanks,

Jessica Zhang

> 
> Signed-off-by: John Watts <contact@jookia.org>
> ---
>   drivers/gpu/drm/panel/panel-newvision-nv3052c.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/panel/panel-newvision-nv3052c.c b/drivers/gpu/drm/panel/panel-newvision-nv3052c.c
> index 2526b123b1f5..307335d0f1fc 100644
> --- a/drivers/gpu/drm/panel/panel-newvision-nv3052c.c
> +++ b/drivers/gpu/drm/panel/panel-newvision-nv3052c.c
> @@ -289,6 +289,9 @@ static int nv3052c_unprepare(struct drm_panel *panel)
>   	struct mipi_dbi *dbi = &priv->dbi;
>   	int err;
>   
> +	/* Wait 150ms in case we just exited sleep mode */
> +	msleep(150);
> +
>   	err = mipi_dbi_command(dbi, MIPI_DCS_ENTER_SLEEP_MODE);
>   	if (err)
>   		dev_err(priv->dev, "Unable to enter sleep mode: %d\n", err);
> -- 
> 2.42.0
>