Re: [PATCH v1 3/4] drm/mediatek: fix boot up for 720 and 480 but 1080

[CK Hu]

Hi, Frank:

On Tue, 2019-04-16 at 16:58 +0200, Frank Wunderlich wrote:
> From: chunhui dai <chunhui.dai@xxxxxxxxxxxx>
> 
> - 1080 plg in/out with ng/ok
> - support other resolutions like 1280x1024

The description is so simple and I could not understand why
pll_default_off could fix this problem. And why only MT2701 has this
problem? Please describe more clear about this patch.

Regards,
CK

> 
> Signed-off-by: chunhui dai <chunhui.dai@xxxxxxxxxxxx>
> Signed-off-by: Frank Wunderlich <frank-w@xxxxxxxxxxxxxxx>
> Tested-by: Frank Wunderlich <frank-w@xxxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/mediatek/mtk_hdmi_phy.c        | 3 +++
>  drivers/gpu/drm/mediatek/mtk_hdmi_phy.h        | 1 +
>  drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c | 1 +
>  3 files changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c
> index 5223498502c4..edadb7a700f1 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.c
> @@ -184,6 +184,9 @@ static int mtk_hdmi_phy_probe(struct platform_device *pdev)
>  		return PTR_ERR(phy_provider);
>  	}
> 
> +	if (hdmi_phy->conf->pll_default_off)
> +		hdmi_phy->conf->hdmi_phy_disable_tmds(hdmi_phy);
> +
>  	return of_clk_add_provider(dev->of_node, of_clk_src_simple_get,
>  				   hdmi_phy->pll);
>  }
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h
> index 2d8b3182470d..f472fdeb63dc 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi_phy.h
> @@ -22,6 +22,7 @@ struct mtk_hdmi_phy;
>  struct mtk_hdmi_phy_conf {
>  	bool tz_disabled;
>  	unsigned long flags;
> +	bool pll_default_off;
>  	const struct clk_ops *hdmi_phy_clk_ops;
>  	void (*hdmi_phy_enable_tmds)(struct mtk_hdmi_phy *hdmi_phy);
>  	void (*hdmi_phy_disable_tmds)(struct mtk_hdmi_phy *hdmi_phy);
> diff --git a/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c b/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c
> index d3cc4022e988..6fbedacfc1e8 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c
> +++ b/drivers/gpu/drm/mediatek/mtk_mt2701_hdmi_phy.c
> @@ -239,6 +239,7 @@ static void mtk_hdmi_phy_disable_tmds(struct mtk_hdmi_phy *hdmi_phy)
>  struct mtk_hdmi_phy_conf mtk_hdmi_phy_2701_conf = {
>  	.tz_disabled = true,
>  	.flags = CLK_SET_RATE_GATE,
> +	.pll_default_off = true,
>  	.hdmi_phy_clk_ops = &mtk_hdmi_phy_pll_ops,
>  	.hdmi_phy_enable_tmds = mtk_hdmi_phy_enable_tmds,
>  	.hdmi_phy_disable_tmds = mtk_hdmi_phy_disable_tmds,
> --
> 2.17.1
>