Re: [PATCH] drm: mediatek: Modify dpi power on/off sequence.

From: CK Hu (胡俊光)
Date: Tue Nov 08 2022 - 02:45:20 EST


Hi, Xinlei:

On Wed, 2022-10-12 at 15:48 +0800, xinlei.lee wrote:
> On Mon, 2022-09-05 at 21:53 +0800, xinlei.lee@xxxxxxxxxxxx wrote:
> > From: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
> >
> > Modify dpi power on/off sequence so that the first gpio operation
> > will take effect.
> >
> > Fixes: 6bd4763fd532 ("drm/mediatek: set dpi pin mode to gpio low to
> > avoid leakage
> > current")
> >
> > Signed-off-by: Xinlei Lee <xinlei.lee@xxxxxxxxxxxx>
> >
> > ---
> > Base on the branch of Linux-next/master.
> > Because dpi power_on/off is protected by dpi->refcount, the first
> > time
> > it cannot be powered on and off successfully, it will cause
> > leakage.
> > ---
> > ---
> > drivers/gpu/drm/mediatek/mtk_dpi.c | 12 ++++++------
> > 1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c
> > b/drivers/gpu/drm/mediatek/mtk_dpi.c
> > index 630a4e301ef6..2ce1a39ce3bf 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> > @@ -462,9 +462,6 @@ static void mtk_dpi_power_off(struct mtk_dpi
> > *dpi)
> > if (--dpi->refcount != 0)
> > return;
> >
> > - if (dpi->pinctrl && dpi->pins_gpio)
> > - pinctrl_select_state(dpi->pinctrl, dpi->pins_gpio);
> > -
> > mtk_dpi_disable(dpi);
> > clk_disable_unprepare(dpi->pixel_clk);
> > clk_disable_unprepare(dpi->engine_clk);
> > @@ -489,9 +486,6 @@ static int mtk_dpi_power_on(struct mtk_dpi
> > *dpi)
> > goto err_pixel;
> > }
> >
> > - if (dpi->pinctrl && dpi->pins_dpi)
> > - pinctrl_select_state(dpi->pinctrl, dpi->pins_dpi);
> > -
> > return 0;
> >
> > err_pixel:
> > @@ -721,6 +715,9 @@ static void mtk_dpi_bridge_disable(struct
> > drm_bridge *bridge)
> > {
> > struct mtk_dpi *dpi = bridge_to_dpi(bridge);
> >
> > + if (dpi->pinctrl && dpi->pins_gpio)
> > + pinctrl_select_state(dpi->pinctrl, dpi->pins_gpio);

I think this should be placed after mtk_dpi_power_off().

> > +
> > mtk_dpi_power_off(dpi);
> > }
> >
> > @@ -728,6 +725,9 @@ static void mtk_dpi_bridge_enable(struct
> > drm_bridge *bridge)
> > {
> > struct mtk_dpi *dpi = bridge_to_dpi(bridge);
> >
> > + if (dpi->pinctrl && dpi->pins_dpi)
> > + pinctrl_select_state(dpi->pinctrl, dpi->pins_dpi);
> > +
> > mtk_dpi_power_on(dpi);
> > mtk_dpi_set_display_mode(dpi, &dpi->mode);
> > mtk_dpi_enable(dpi);
>
> Hi CK,
>
> Gentle ping for this patch, if there is anything I need to modify,
> please kindly let me know.
>
> Best Regards!
> xinlei
>