Re: [PATCH] drm: bridge: samsung-dsim: Don't use FORCE_STOP_STATE

From: Dario Binacchi
Date: Tue Jan 30 2024 - 04:12:36 EST


Hi Michael,

On Mon, Jan 29, 2024 at 5:06 PM Michael Walle <mwalle@xxxxxxxxxx> wrote:
>
> >> Just FYI this conflictted pretty heavily with drm-misc-next changes in
> >> the same area, someone should check drm-tip has the correct
> >> resolution, I'm not really sure what is definitely should be.
> >
> > FWIW, this looks rather messy now. The drm-tip doesn't build.
> >
> > There was a new call to samsung_dsim_set_stop_state() introduced
> > in commit b2fe2292624ac (drm: bridge: samsung-dsim: enter display
> > mode in the enable() callback).
>
> I had a closer look at the latest linux-next (where somehow my patch
> made it into) and tried to apply commit b2fe2292624ac (drm: bridge:
> samsung-dsim: enter display mode in the enable() callback). It looks
> like only the following hunk is still needed from that patch. Everything
> else is covered by this fixes patch.
>
> Dario, could you rebase your commit onto this patch? I had a quick test
> with this change and it seems to work fine for our case.
>
> --snip--
> diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c
> b/drivers/gpu/drm/bridge/samsung-dsim.c
> index 63a1a0c88be4..92755c90e7d2 100644
> --- a/drivers/gpu/drm/bridge/samsung-dsim.c
> +++ b/drivers/gpu/drm/bridge/samsung-dsim.c
> @@ -1498,6 +1498,8 @@ static void samsung_dsim_atomic_disable(struct
> drm_bridge *bridge,
> if (!(dsi->state & DSIM_STATE_ENABLED))
> return;
>
> + samsung_dsim_set_display_enable(dsi, false);
> +
> dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;
> }
>
> @@ -1506,8 +1508,6 @@ static void
> samsung_dsim_atomic_post_disable(struct drm_bridge *bridge,
> {
> struct samsung_dsim *dsi = bridge_to_dsi(bridge);
>
> - samsung_dsim_set_display_enable(dsi, false);
> -
> dsi->state &= ~DSIM_STATE_ENABLED;
> pm_runtime_put_sync(dsi->dev);
> }
> --snip--
>
> -michael

I'm sorry, but I didn't understand well what I have to do.
This is what I have done:

git clone https://kernel.googlesource.com/pub/scm/linux/kernel/git/next/linux-next.git
cd linux-next
# add your changes, the ones of the emails
git am --reject 0001-drm-bridge-samsung-dsim-enter-display-mode-in-the-en.patch

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c
b/drivers/gpu/drm/bridge/samsung-dsim.c
index 92755c90e7d2..b47929072583 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -1508,6 +1508,9 @@ static void
samsung_dsim_atomic_post_disable(struct drm_bridge *bridge,
{
struct samsung_dsim *dsi = bridge_to_dsi(bridge);

+ if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type))
+ samsung_dsim_set_stop_state(dsi, true);
+
dsi->state &= ~DSIM_STATE_ENABLED;
pm_runtime_put_sync(dsi->dev);
}

And then test the driver for my use case.

Is everything I wrote correct, or am I making a mistake?

Thanks and regards,
Dario

--

Dario Binacchi

Senior Embedded Linux Developer

dario.binacchi@xxxxxxxxxxxxxxxxxxxx

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