[PATCH v11 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver

CK Hu ck.hu at mediatek.com
Sun Jun 19 20:19:52 PDT 2022


On Mon, 2022-06-20 at 11:12 +0800, CK Hu wrote:
> On Fri, 2022-06-10 at 18:55 +0800, Bo-Chen Chen wrote:
> > From: Markus Schneider-Pargmann <msp at baylibre.com>
> > 
> > This patch adds a embedded displayport driver for the MediaTek
> > mt8195
> > SoC.
> > 
> > It supports the MT8195, the embedded DisplayPort units. It offers
> > DisplayPort 1.4 with up to 4 lanes.
> > 
> > The driver creates a child device for the phy. The child device
> > will
> > never exist without the parent being active. As they are sharing a
> > register range, the parent passes a regmap pointer to the child so
> > that
> > both can work with the same register range. The phy driver sets
> > device
> > data that is read by the parent to get the phy device that can be
> > used
> > to control the phy properties.
> > 
> > This driver is based on an initial version by
> > Jitao shi <jitao.shi at mediatek.com>
> > 
> > Signed-off-by: Markus Schneider-Pargmann <msp at baylibre.com>
> > Signed-off-by: Guillaume Ranquet <granquet at baylibre.com>
> > [Bo-Chen: Cleanup the drivers and modify comments from reviewers]
> > Signed-off-by: Bo-Chen Chen <rex-bc.chen at mediatek.com>
> > ---
> 
> [snip]
> 
> > +
> > +static void mtk_dp_calculate_pixrate(struct mtk_dp *mtk_dp)
> > +{
> > +	u8 target_frame_rate = 60;
> > +	u32 target_pixel_clk;
> > +	struct drm_display_mode mode;
> > +	struct mtk_dp_timings *timings = &mtk_dp->info.timings;
> > +
> > +	drm_display_mode_from_videomode(&timings->vm, &mode);
> > +
> > +	if (mtk_dp->info.timings.frame_rate > 0) {
> > +		target_frame_rate = mtk_dp->info.timings.frame_rate;
> > +		target_pixel_clk = mode.htotal * mode.vtotal *
> > +				   target_frame_rate;
> > +	} else if (mtk_dp->info.timings.pix_rate_khz > 0) {
> > +		target_pixel_clk = mtk_dp->info.timings.pix_rate_khz *
> > 1000;
> > +	} else {
> > +		target_pixel_clk = mode.htotal * mode.vtotal *
> > +				   target_frame_rate;
> > +	}
> > +
> > +	mtk_dp->info.timings.pix_rate_khz = target_pixel_clk / 1000;
> 
> It seems that pix_rate_khz is used only here and does not used in
> another place, so pix_rate_khz is useless, remove it.

It seems that frame_rate is also redundant, so remove it.

Regards,
CK

> 
> Regards,
> CK
> 
> > +}
> > +




More information about the Linux-mediatek mailing list