Hi, Bibby: This looks reasonable, but why MT8173 doesn't need this patch? So describe more about why MT7623 need this patch. If this is caused by latest DRM core flow change, I think we should treat this patch independent with MT7623. Regards, CK On Wed, 2018-09-05 at 16:31 +0800, Bibby Hsieh wrote: > From: chunhui dai <chunhui.dai@xxxxxxxxxxxx> > > add refcount for DPI power on/off to protect the flow > > Signed-off-by: chunhui dai <chunhui.dai@xxxxxxxxxxxx> > --- > drivers/gpu/drm/mediatek/mtk_dpi.c | 16 ++++++++++++++-- > 1 file changed, 14 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c > index 6c0ea39d5739..d9373e67d328 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dpi.c > +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c > @@ -77,6 +77,7 @@ struct mtk_dpi { > enum mtk_dpi_out_bit_num bit_num; > enum mtk_dpi_out_channel_swap channel_swap; > bool power_sta; > + int refcount; > u8 power_ctl; > }; > > @@ -369,6 +370,12 @@ static void mtk_dpi_config_color_format(struct mtk_dpi *dpi, > > static void mtk_dpi_power_off(struct mtk_dpi *dpi, enum mtk_dpi_power_ctl pctl) > { > + if (WARN_ON(dpi->refcount == 0)) > + return; > + > + if (--dpi->refcount != 0) > + return; > + > dpi->power_ctl &= ~pctl; > > if ((dpi->power_ctl & DPI_POWER_START) || > @@ -388,14 +395,17 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi, enum mtk_dpi_power_ctl pctl) > { > int ret; > > + if (++dpi->refcount != 1) > + return 0; > + > dpi->power_ctl |= pctl; > > if (!(dpi->power_ctl & DPI_POWER_START) && > !(dpi->power_ctl & DPI_POWER_ENABLE)) > - return 0; > + goto err_refcount; > > if (dpi->power_sta) > - return 0; > + goto err_refcount; > > ret = clk_prepare_enable(dpi->engine_clk); > if (ret) { > @@ -417,6 +427,8 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi, enum mtk_dpi_power_ctl pctl) > clk_disable_unprepare(dpi->engine_clk); > err_eng: > dpi->power_ctl &= ~pctl; > +err_refcount: > + dpi->refcount--; > return ret; > } > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel