| Message ID | 1647503611-13144-5-git-send-email-xinlei.lee@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Cooperate with DSI RX devices to modify dsi funcs and delay mipi high to cooperate with panel sequence | expand |
Hello Xinlei, On Thu, 2022-03-17 at 15:53 +0800, xinlei.lee@mediatek.com wrote: > From: Xinlei Lee <xinlei.lee@mediatek.com> > > In the dsi_enable function, mtk_dsi_rxtx_control is to > pull up the MIPI signal operation. Before dsi_disable, > MIPI should also be pulled down by writing a register instead of > disabling dsi. > What will happen if you do not pulled down the mipi before disable dsi? What's differnet for this two setting? > Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> > Signed-off-by: Xinlei Lee <xinlei.lee@mediatek.com> > --- > drivers/gpu/drm/mediatek/mtk_dsi.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c > b/drivers/gpu/drm/mediatek/mtk_dsi.c > index b509d59235e2..1c6a75a46b67 100644 > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c > @@ -676,6 +676,8 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi) > mtk_dsi_reset_engine(dsi); > mtk_dsi_lane0_ulp_mode_enter(dsi); > mtk_dsi_clk_ulp_mode_enter(dsi); > + /* set the lane number as 0 */ > + writel(0, dsi->regs + DSI_TXRX_CTRL); So set lane num to 0 means pull down mipi? BRs, Rex > > mtk_dsi_disable(dsi); >
On Thu, 2022-03-17 at 20:20 +0800, Rex-BC Chen wrote: > Hello Xinlei, > > On Thu, 2022-03-17 at 15:53 +0800, xinlei.lee@mediatek.com wrote: > > From: Xinlei Lee <xinlei.lee@mediatek.com> > > > > In the dsi_enable function, mtk_dsi_rxtx_control is to > > pull up the MIPI signal operation. Before dsi_disable, > > MIPI should also be pulled down by writing a register instead of > > disabling dsi. > > > > What will happen if you do not pulled down the mipi before disable > dsi? > What's differnet for this two setting? > > > Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> > > Signed-off-by: Xinlei Lee <xinlei.lee@mediatek.com> > > --- > > drivers/gpu/drm/mediatek/mtk_dsi.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c > > b/drivers/gpu/drm/mediatek/mtk_dsi.c > > index b509d59235e2..1c6a75a46b67 100644 > > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c > > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c > > @@ -676,6 +676,8 @@ static void mtk_dsi_poweroff(struct mtk_dsi > > *dsi) > > mtk_dsi_reset_engine(dsi); > > mtk_dsi_lane0_ulp_mode_enter(dsi); > > mtk_dsi_clk_ulp_mode_enter(dsi); > > + /* set the lane number as 0 */ > > + writel(0, dsi->regs + DSI_TXRX_CTRL); > > So set lane num to 0 means pull down mipi? > > BRs, > Rex > > > > > mtk_dsi_disable(dsi); > > > > Hi rex: 1. If you disable dsi without pulling the mipi signal low, the value of the register will still maintain the setting of the mipi signal being pulled high. After resume, even if the mipi signal is not pulled high, it will still be in the high state. 2.So set lane num to 0 means pull down mipi => yes Do you have any suggestions on the next version? Best Regards! xinlei
On Tue, 2022-03-22 at 18:00 +0800, xinlei.lee wrote: > On Thu, 2022-03-17 at 20:20 +0800, Rex-BC Chen wrote: > > Hello Xinlei, > > > > On Thu, 2022-03-17 at 15:53 +0800, xinlei.lee@mediatek.com wrote: > > > From: Xinlei Lee <xinlei.lee@mediatek.com> > > > > > > In the dsi_enable function, mtk_dsi_rxtx_control is to > > > pull up the MIPI signal operation. Before dsi_disable, > > > MIPI should also be pulled down by writing a register instead of > > > disabling dsi. > > > > > > > What will happen if you do not pulled down the mipi before disable > > dsi? > > What's differnet for this two setting? > > > > > Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> > > > Signed-off-by: Xinlei Lee <xinlei.lee@mediatek.com> > > > --- > > > drivers/gpu/drm/mediatek/mtk_dsi.c | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c > > > b/drivers/gpu/drm/mediatek/mtk_dsi.c > > > index b509d59235e2..1c6a75a46b67 100644 > > > --- a/drivers/gpu/drm/mediatek/mtk_dsi.c > > > +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c > > > @@ -676,6 +676,8 @@ static void mtk_dsi_poweroff(struct mtk_dsi > > > *dsi) > > > mtk_dsi_reset_engine(dsi); > > > mtk_dsi_lane0_ulp_mode_enter(dsi); > > > mtk_dsi_clk_ulp_mode_enter(dsi); > > > + /* set the lane number as 0 */ Hello Xinlei, I think you can write this comment more detailed, like "/* set the lane number as 0 to pull down mipi */" > > > + writel(0, dsi->regs + DSI_TXRX_CTRL); > > > > So set lane num to 0 means pull down mipi? > > > > BRs, > > Rex > > > > > > > > mtk_dsi_disable(dsi); > > > > > > > > > Hi rex: > > 1. > If you disable dsi without pulling the mipi signal low, the value of > the register will still maintain the setting of the mipi signal being > pulled high. > After resume, even if the mipi signal is not pulled high, it will > still > be in the high state. > I think you can describe this in commit message BRs, Rex > 2.So set lane num to 0 means pull down mipi > => yes > > Do you have any suggestions on the next version? > > Best Regards! > xinlei >
diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c index b509d59235e2..1c6a75a46b67 100644 --- a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -676,6 +676,8 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi) mtk_dsi_reset_engine(dsi); mtk_dsi_lane0_ulp_mode_enter(dsi); mtk_dsi_clk_ulp_mode_enter(dsi); + /* set the lane number as 0 */ + writel(0, dsi->regs + DSI_TXRX_CTRL); mtk_dsi_disable(dsi);