From: Jitao Shi <jitao.shi@mediatek.com>

Old sequence:
1. Pull the MIPI signal high
2. Delay & Dsi_reset
3. Set the dsi timing register
4. dsi clk & lanes leave ulp mode and enter hs mode

New sequence:
1. Set the dsi timing register
2. Pull the MIPI signal high
3. Delay & Dsi_reset
4. dsi clk & lanes leave ulp mode and enter hs mode

In the new sequence 2 & 3 & 4 will be moved to dsi_enbale in later patch.

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 | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index ccb0511b9cd5..262c027d8c2f 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -649,14 +649,14 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
 	mtk_dsi_reset_engine(dsi);
 	mtk_dsi_phy_timconfig(dsi);
 
-	mtk_dsi_rxtx_control(dsi);
-	usleep_range(30, 100);
-	mtk_dsi_reset_dphy(dsi);
 	mtk_dsi_ps_control_vact(dsi);
 	mtk_dsi_set_vm_cmd(dsi);
 	mtk_dsi_config_vdo_timing(dsi);
 	mtk_dsi_set_interrupt_enable(dsi);
 
+	mtk_dsi_rxtx_control(dsi);
+	usleep_range(30, 100);
+	mtk_dsi_reset_dphy(dsi);
 	mtk_dsi_clk_ulp_mode_leave(dsi);
 	mtk_dsi_lane0_ulp_mode_leave(dsi);
 	mtk_dsi_clk_hs_mode(dsi, 0);
-- 
2.18.0

Hi, Xinlei:

On Thu, 2022-03-17 at 15:53 +0800, xinlei.lee@mediatek.com wrote:
> From: Jitao Shi <jitao.shi@mediatek.com>
> 
> Old sequence:
> 1. Pull the MIPI signal high
> 2. Delay & Dsi_reset
> 3. Set the dsi timing register
> 4. dsi clk & lanes leave ulp mode and enter hs mode
> 
> New sequence:
> 1. Set the dsi timing register
> 2. Pull the MIPI signal high
> 3. Delay & Dsi_reset
> 4. dsi clk & lanes leave ulp mode and enter hs mode
> 
> In the new sequence 2 & 3 & 4 will be moved to dsi_enbale in later
> patch.

I think there would be one patch in 5.9 make the wrong sequence, so add
'Fixes' tag to indicate which patch make the wrong sequence. Use the
term correct/wrong instead old/new sequence.

I still do not understand what is the sequence after apply this patch?

Does the sequence is this after apply this patch?
1. Set the dsi timing register
2. Pull the MIPI signal high
3. Delay & Dsi_reset
4. dsi clk & lanes leave ulp mode and enter hs mode

Regards,
CK

> 
> 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 | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c
> b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index ccb0511b9cd5..262c027d8c2f 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -649,14 +649,14 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
>  	mtk_dsi_reset_engine(dsi);
>  	mtk_dsi_phy_timconfig(dsi);
>  
> -	mtk_dsi_rxtx_control(dsi);
> -	usleep_range(30, 100);
> -	mtk_dsi_reset_dphy(dsi);
>  	mtk_dsi_ps_control_vact(dsi);
>  	mtk_dsi_set_vm_cmd(dsi);
>  	mtk_dsi_config_vdo_timing(dsi);
>  	mtk_dsi_set_interrupt_enable(dsi);
>  
> +	mtk_dsi_rxtx_control(dsi);
> +	usleep_range(30, 100);
> +	mtk_dsi_reset_dphy(dsi);
>  	mtk_dsi_clk_ulp_mode_leave(dsi);
>  	mtk_dsi_lane0_ulp_mode_leave(dsi);
>  	mtk_dsi_clk_hs_mode(dsi, 0);

Hello Xinlei,

Thanks for your patch, and there are something I want to know:

On Thu, 2022-03-17 at 15:53 +0800, xinlei.lee@mediatek.com wrote:
> From: Jitao Shi <jitao.shi@mediatek.com>
> 
> Old sequence:
> 1. Pull the MIPI signal high
> 2. Delay & Dsi_reset
> 3. Set the dsi timing register
> 4. dsi clk & lanes leave ulp mode and enter hs mode
> 
> New sequence:
> 1. Set the dsi timing register
> 2. Pull the MIPI signal high
> 3. Delay & Dsi_reset
> 4. dsi clk & lanes leave ulp mode and enter hs mode
> 

Could you explain why you want to change original power on sequence?
From this commit message, I don't know why you want to do this.
If the reason is in cover letter, I think you should move them here.

> In the new sequence 2 & 3 & 4 will be moved to dsi_enbale in later
> patch.

I think this is no need to describe here.

BRs,
Rex
> 
> 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 | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c
> b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index ccb0511b9cd5..262c027d8c2f 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -649,14 +649,14 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
>  	mtk_dsi_reset_engine(dsi);
>  	mtk_dsi_phy_timconfig(dsi);
>  
> -	mtk_dsi_rxtx_control(dsi);
> -	usleep_range(30, 100);
> -	mtk_dsi_reset_dphy(dsi);
>  	mtk_dsi_ps_control_vact(dsi);
>  	mtk_dsi_set_vm_cmd(dsi);
>  	mtk_dsi_config_vdo_timing(dsi);
>  	mtk_dsi_set_interrupt_enable(dsi);
>  
> +	mtk_dsi_rxtx_control(dsi);
> +	usleep_range(30, 100);
> +	mtk_dsi_reset_dphy(dsi);
>  	mtk_dsi_clk_ulp_mode_leave(dsi);
>  	mtk_dsi_lane0_ulp_mode_leave(dsi);
>  	mtk_dsi_clk_hs_mode(dsi, 0);