[RESEND PATCH v9 1/2] drm: bridge: samsung-dsim: enter display mode in the enable() callback

From: Dario Binacchi
Date: Mon Jan 15 2024 - 05:34:44 EST


The synaptics-r63353 (panel-bridge) can only be configured in command mode.
So, samsung-dsim (bridge) must not be in display mode during the
prepare()/unprepare() of the panel-bridge. Setting the
"pre_enable_prev_first" flag to true allows the prepare() of the
panel-bridge to be called between the pre_enabled() and enabled() of the
bridge. So, the bridge can enter display mode only in the enabled().
The unprepare() of the panel-bridge is instead called between the disable()
and post_disable() of the bridge. So, the disable() must exit the display
mode (i .e. enter command mode) to allow the panel-bridge to receive DSI
commands.

samsung_dsim_atomic_pre_enable -> command mode
r63353_panel_prepare -> send DSI commands
samsung_dsim_atomic_enable -> enter display mode

samsung_dsim_atomic_disable -> exit display mode (command mode)
r63353_panel_unprepare -> send DSI commands
samsung_dsim_atomic_post_disable

Co-developed-by: Michael Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Michael Trimarchi <michael@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
---

(no changes since v1)

drivers/gpu/drm/bridge/samsung-dsim.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index be5914caa17d..15bf05b2bbe4 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -1494,7 +1494,6 @@ static void samsung_dsim_atomic_pre_enable(struct drm_bridge *bridge,
return;

samsung_dsim_set_display_mode(dsi);
- samsung_dsim_set_display_enable(dsi, true);
}
}

@@ -1507,6 +1506,7 @@ static void samsung_dsim_atomic_enable(struct drm_bridge *bridge,
samsung_dsim_set_display_mode(dsi);
samsung_dsim_set_display_enable(dsi, true);
} else {
+ samsung_dsim_set_display_enable(dsi, true);
samsung_dsim_set_stop_state(dsi, false);
}

@@ -1524,6 +1524,8 @@ static void samsung_dsim_atomic_disable(struct drm_bridge *bridge,
if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type))
samsung_dsim_set_stop_state(dsi, true);

+ samsung_dsim_set_display_enable(dsi, false);
+
dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;
}

@@ -1532,7 +1534,8 @@ 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);
+ 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);
--
2.43.0