[RFT,v2,1/3] drm/bridge: tc358762: Set pre_enable_prev_first

  Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
order"). This should allow us to revert commit ec7981e6c614
("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
time").

Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---

(no changes since v1)

 drivers/gpu/drm/bridge/tc358762.c | 1 +
 1 file changed, 1 insertion(+)
  

On Tue, 31 Jan 2023 at 22:22, Douglas Anderson <dianders@chromium.org> wrote:
>
> Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
> ("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
> order"). This should allow us to revert commit ec7981e6c614
> ("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
> commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
> time").

I see no reference in the TC358762 datasheet to requiring the DSI
interface to be in any particular state.
However, setting this flag does mean that the DSI host doesn't need to
power up and down for each host_transfer request from
tc358762_pre_enable/tc358762_init, so on that basis I'm good with it.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

> Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
>
> (no changes since v1)
>
>  drivers/gpu/drm/bridge/tc358762.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
> index 0b6a28436885..77f7f7f54757 100644
> --- a/drivers/gpu/drm/bridge/tc358762.c
> +++ b/drivers/gpu/drm/bridge/tc358762.c
> @@ -229,6 +229,7 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
>         ctx->bridge.funcs = &tc358762_bridge_funcs;
>         ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
>         ctx->bridge.of_node = dev->of_node;
> +       ctx->bridge.pre_enable_prev_first = true;
>
>         drm_bridge_add(&ctx->bridge);
>
> --
> 2.39.1.456.gfc5497dd1b-goog
>
  

Hi,

On Wed, Feb 1, 2023 at 1:51 AM Dave Stevenson
<dave.stevenson@raspberrypi.com> wrote:
>
> On Tue, 31 Jan 2023 at 22:22, Douglas Anderson <dianders@chromium.org> wrote:
> >
> > Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
> > ("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
> > order"). This should allow us to revert commit ec7981e6c614
> > ("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
> > commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
> > time").
>
> I see no reference in the TC358762 datasheet to requiring the DSI
> interface to be in any particular state.
> However, setting this flag does mean that the DSI host doesn't need to
> power up and down for each host_transfer request from
> tc358762_pre_enable/tc358762_init, so on that basis I'm good with it.
>
> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
>
> > Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
> > Signed-off-by: Douglas Anderson <dianders@chromium.org>
> > ---
> >
> > (no changes since v1)
> >
> >  drivers/gpu/drm/bridge/tc358762.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
> > index 0b6a28436885..77f7f7f54757 100644
> > --- a/drivers/gpu/drm/bridge/tc358762.c
> > +++ b/drivers/gpu/drm/bridge/tc358762.c
> > @@ -229,6 +229,7 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
> >         ctx->bridge.funcs = &tc358762_bridge_funcs;
> >         ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
> >         ctx->bridge.of_node = dev->of_node;
> > +       ctx->bridge.pre_enable_prev_first = true;
> >
> >         drm_bridge_add(&ctx->bridge);

Abhinav asked what the plan was for landing this [1]. Since this isn't
urgent, I guess the plan is to land patch #1 in drm-misc-next. Then we
sit and wait until it percolates into mainline and, once it does, then
patch #2 and #3 can land.

Since I have Dave's review I can commit this to drm-misc-next myself.
My plan will be to wait until Thursday or Friday of this week (to give
people a bit of time to object) and then land patch #1. Then I'll
snooze things for a while and poke Abhinav and Dmitry to land patch #2
/ #3 when I notice it in mainline. If, at any point, someone comes out
of the woodwork and yells that this is breaking them then, worst case,
we can revert.

[1] https://lore.kernel.org/r/1f204585-88e2-abae-1216-92f739ac9e91@quicinc.com/
  

On 28/02/2023 02:26, Doug Anderson wrote:
> Hi,
> 
> On Wed, Feb 1, 2023 at 1:51 AM Dave Stevenson
> <dave.stevenson@raspberrypi.com> wrote:
>>
>> On Tue, 31 Jan 2023 at 22:22, Douglas Anderson <dianders@chromium.org> wrote:
>>>
>>> Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
>>> ("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
>>> order"). This should allow us to revert commit ec7981e6c614
>>> ("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
>>> commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
>>> time").
>>
>> I see no reference in the TC358762 datasheet to requiring the DSI
>> interface to be in any particular state.
>> However, setting this flag does mean that the DSI host doesn't need to
>> power up and down for each host_transfer request from
>> tc358762_pre_enable/tc358762_init, so on that basis I'm good with it.
>>
>> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
>>
>>> Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
>>> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
>>> Signed-off-by: Douglas Anderson <dianders@chromium.org>
>>> ---
>>>
>>> (no changes since v1)
>>>
>>>   drivers/gpu/drm/bridge/tc358762.c | 1 +
>>>   1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
>>> index 0b6a28436885..77f7f7f54757 100644
>>> --- a/drivers/gpu/drm/bridge/tc358762.c
>>> +++ b/drivers/gpu/drm/bridge/tc358762.c
>>> @@ -229,6 +229,7 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
>>>          ctx->bridge.funcs = &tc358762_bridge_funcs;
>>>          ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
>>>          ctx->bridge.of_node = dev->of_node;
>>> +       ctx->bridge.pre_enable_prev_first = true;
>>>
>>>          drm_bridge_add(&ctx->bridge);
> 
> Abhinav asked what the plan was for landing this [1]. Since this isn't
> urgent, I guess the plan is to land patch #1 in drm-misc-next. Then we
> sit and wait until it percolates into mainline and, once it does, then
> patch #2 and #3 can land.
> 
> Since I have Dave's review I can commit this to drm-misc-next myself.
> My plan will be to wait until Thursday or Friday of this week (to give
> people a bit of time to object) and then land patch #1. Then I'll
> snooze things for a while and poke Abhinav and Dmitry to land patch #2
> / #3 when I notice it in mainline. If, at any point, someone comes out
> of the woodwork and yells that this is breaking them then, worst case,
> we can revert.

This plan sounds good to me.

> 
> [1] https://lore.kernel.org/r/1f204585-88e2-abae-1216-92f739ac9e91@quicinc.com/
  

On 01/02/2023 00:18, Douglas Anderson wrote:
> Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
> ("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
> order"). This should allow us to revert commit ec7981e6c614
> ("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
> commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
> time").
> 
> Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
> Signed-off-by: Douglas Anderson <dianders@chromium.org>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
  

Hi,

On Mon, Feb 27, 2023 at 5:24 PM Dmitry Baryshkov
<dmitry.baryshkov@linaro.org> wrote:
>
> On 28/02/2023 02:26, Doug Anderson wrote:
> > Hi,
> >
> > On Wed, Feb 1, 2023 at 1:51 AM Dave Stevenson
> > <dave.stevenson@raspberrypi.com> wrote:
> >>
> >> On Tue, 31 Jan 2023 at 22:22, Douglas Anderson <dianders@chromium.org> wrote:
> >>>
> >>> Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
> >>> ("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
> >>> order"). This should allow us to revert commit ec7981e6c614
> >>> ("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
> >>> commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
> >>> time").
> >>
> >> I see no reference in the TC358762 datasheet to requiring the DSI
> >> interface to be in any particular state.
> >> However, setting this flag does mean that the DSI host doesn't need to
> >> power up and down for each host_transfer request from
> >> tc358762_pre_enable/tc358762_init, so on that basis I'm good with it.
> >>
> >> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> >>
> >>> Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
> >>> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> >>> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
> >>> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> >>> ---
> >>>
> >>> (no changes since v1)
> >>>
> >>>   drivers/gpu/drm/bridge/tc358762.c | 1 +
> >>>   1 file changed, 1 insertion(+)
> >>>
> >>> diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
> >>> index 0b6a28436885..77f7f7f54757 100644
> >>> --- a/drivers/gpu/drm/bridge/tc358762.c
> >>> +++ b/drivers/gpu/drm/bridge/tc358762.c
> >>> @@ -229,6 +229,7 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
> >>>          ctx->bridge.funcs = &tc358762_bridge_funcs;
> >>>          ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
> >>>          ctx->bridge.of_node = dev->of_node;
> >>> +       ctx->bridge.pre_enable_prev_first = true;
> >>>
> >>>          drm_bridge_add(&ctx->bridge);
> >
> > Abhinav asked what the plan was for landing this [1]. Since this isn't
> > urgent, I guess the plan is to land patch #1 in drm-misc-next. Then we
> > sit and wait until it percolates into mainline and, once it does, then
> > patch #2 and #3 can land.
> >
> > Since I have Dave's review I can commit this to drm-misc-next myself.
> > My plan will be to wait until Thursday or Friday of this week (to give
> > people a bit of time to object) and then land patch #1. Then I'll
> > snooze things for a while and poke Abhinav and Dmitry to land patch #2
> > / #3 when I notice it in mainline. If, at any point, someone comes out
> > of the woodwork and yells that this is breaking them then, worst case,
> > we can revert.
>
> This plan sounds good to me.

Pushed to drm-misc-next:

55cac10739d5 drm/bridge: tc358762: Set pre_enable_prev_first

If my math is right then I'd expect that to get into mainline for
6.4-rc1. I guess that means it'll be in Linus's tree mid-May. I'll
schedule a reminder to suggest landing at patches #2 and #3 again in
late May.

-Doug
  

On Thu, 2 Mar 2023 at 19:26, Doug Anderson <dianders@chromium.org> wrote:
>
> Hi,
>
> On Mon, Feb 27, 2023 at 5:24 PM Dmitry Baryshkov
> <dmitry.baryshkov@linaro.org> wrote:
> >
> > On 28/02/2023 02:26, Doug Anderson wrote:
> > > Hi,
> > >
> > > On Wed, Feb 1, 2023 at 1:51 AM Dave Stevenson
> > > <dave.stevenson@raspberrypi.com> wrote:
> > >>
> > >> On Tue, 31 Jan 2023 at 22:22, Douglas Anderson <dianders@chromium.org> wrote:
> > >>>
> > >>> Set the "pre_enable_prev_first" as provided by commit 4fb912e5e190
> > >>> ("drm/bridge: Introduce pre_enable_prev_first to alter bridge init
> > >>> order"). This should allow us to revert commit ec7981e6c614
> > >>> ("drm/msm/dsi: don't powerup at modeset time for parade-ps8640") and
> > >>> commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset
> > >>> time").
> > >>
> > >> I see no reference in the TC358762 datasheet to requiring the DSI
> > >> interface to be in any particular state.
> > >> However, setting this flag does mean that the DSI host doesn't need to
> > >> power up and down for each host_transfer request from
> > >> tc358762_pre_enable/tc358762_init, so on that basis I'm good with it.
> > >>
> > >> Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > >>
> > >>> Cc: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > >>> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > >>> Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
> > >>> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> > >>> ---
> > >>>
> > >>> (no changes since v1)
> > >>>
> > >>>   drivers/gpu/drm/bridge/tc358762.c | 1 +
> > >>>   1 file changed, 1 insertion(+)
> > >>>
> > >>> diff --git a/drivers/gpu/drm/bridge/tc358762.c b/drivers/gpu/drm/bridge/tc358762.c
> > >>> index 0b6a28436885..77f7f7f54757 100644
> > >>> --- a/drivers/gpu/drm/bridge/tc358762.c
> > >>> +++ b/drivers/gpu/drm/bridge/tc358762.c
> > >>> @@ -229,6 +229,7 @@ static int tc358762_probe(struct mipi_dsi_device *dsi)
> > >>>          ctx->bridge.funcs = &tc358762_bridge_funcs;
> > >>>          ctx->bridge.type = DRM_MODE_CONNECTOR_DPI;
> > >>>          ctx->bridge.of_node = dev->of_node;
> > >>> +       ctx->bridge.pre_enable_prev_first = true;
> > >>>
> > >>>          drm_bridge_add(&ctx->bridge);
> > >
> > > Abhinav asked what the plan was for landing this [1]. Since this isn't
> > > urgent, I guess the plan is to land patch #1 in drm-misc-next. Then we
> > > sit and wait until it percolates into mainline and, once it does, then
> > > patch #2 and #3 can land.
> > >
> > > Since I have Dave's review I can commit this to drm-misc-next myself.
> > > My plan will be to wait until Thursday or Friday of this week (to give
> > > people a bit of time to object) and then land patch #1. Then I'll
> > > snooze things for a while and poke Abhinav and Dmitry to land patch #2
> > > / #3 when I notice it in mainline. If, at any point, someone comes out
> > > of the woodwork and yells that this is breaking them then, worst case,
> > > we can revert.
> >
> > This plan sounds good to me.
>
> Pushed to drm-misc-next:
>
> 55cac10739d5 drm/bridge: tc358762: Set pre_enable_prev_first
>
> If my math is right then I'd expect that to get into mainline for
> 6.4-rc1. I guess that means it'll be in Linus's tree mid-May. I'll
> schedule a reminder to suggest landing at patches #2 and #3 again in
> late May.

It might be earlier, if msm-next merges drm-misc earlier (e.g. for the
PSR patches).