[PATCH v2] drm/mediatek: dsi: fix scrolling of panel with small hfp or hbp

[Chun-Kuang Hu]

Hi, Jitao:

Chun-Kuang Hu <chunkuang.hu at kernel.org> 於 2020年8月18日 週二 下午10:45寫道：
>
> Hi, Jitao:
>
> Jitao Shi <jitao.shi at mediatek.com> 於 2020年8月18日 週二 上午10:41寫道：
> >
> > On Tue, 2020-08-18 at 07:42 +0800, Chun-Kuang Hu wrote:
> > > Hi, Jitao:
> > >
> > > Jitao Shi <jitao.shi at mediatek.com> 於 2020年8月17日 週一 下午9:07寫道：
> > > >
> > > > horizontal_backporch_byte should be hbp * bpp - hbp extra bytes.
> > > > So remove the wrong subtraction 10.
> > > >
> > > > Signed-off-by: Jitao Shi <jitao.shi at mediatek.com>
> > > > ---
> > > >  drivers/gpu/drm/mediatek/mtk_dsi.c | 9 ++++-----
> > > >  1 file changed, 4 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> > > > index 270bf22c98fe..5d031e634571 100644
> > > > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> > > > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> > > > @@ -473,14 +473,13 @@ static void mtk_dsi_config_vdo_timing(struct mtk_dsi *dsi)
> > > >         horizontal_sync_active_byte = (vm->hsync_len * dsi_tmp_buf_bpp - 10);
> > >
> > > So this subtraction 10 is correct?
> > >
> > > Regards,
> > > Chun-Kuang.
> > >
> >
> > Yes, It is right.
> >
> > In the cea861 and dmt spec the mini hsync is 40 pixels.
> > So the vm->hsync_len * dsi_tmp_buf_bpp >= 120 > 10
> >
>
> OK, so
>
> Reviewed-by: Chun-Kuang Hu <chunkuang.hu at kernel.org>
>

Applied to mediatek-drm-fixes [1], thanks.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-fixes

Regards,
Chun-Kuang.

> > Best Regards
> > jitao
> > > >
> > > >         if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
> > > > -               horizontal_backporch_byte =
> > > > -                       (vm->hback_porch * dsi_tmp_buf_bpp - 10);
> > > > +               horizontal_backporch_byte = vm->hback_porch * dsi_tmp_buf_bpp;
> > > >         else
> > > > -               horizontal_backporch_byte = ((vm->hback_porch + vm->hsync_len) *
> > > > -                       dsi_tmp_buf_bpp - 10);
> > > > +               horizontal_backporch_byte = (vm->hback_porch + vm->hsync_len) *
> > > > +                                           dsi_tmp_buf_bpp;
> > > >
> > > >         data_phy_cycles = timing->lpx + timing->da_hs_prepare +
> > > > -                         timing->da_hs_zero + timing->da_hs_exit + 3;
> > > > +                         timing->da_hs_zero + timing->da_hs_exit;
> > > >
> > > >         if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
> > > >                 if ((vm->hfront_porch + vm->hback_porch) * dsi_tmp_buf_bpp >
> > > > --
> > > > 2.12.5
> > > > _______________________________________________
> > > > Linux-mediatek mailing list
> > > > Linux-mediatek at lists.infradead.org
> > > > http://lists.infradead.org/mailman/listinfo/linux-mediatek
> >