On 09.12.2022 16:23, Jagan Teki wrote:
> From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>
> Restore the proper bridge chain by finding the previous bridge
> in the chain instead of passing NULL.
>
> This establishes a proper bridge chain while attaching downstream
> bridges.
>
> v9, v4:
> * none
>
> v3:
> * new patch
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Signed-off-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
> ---
As we are resurrecting this patch, one more change is needed here:
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
index e5b1540c4ae4..9d10a89d28f1 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -1713,6 +1713,7 @@ static int exynos_dsi_probe(struct platform_device
*pdev)
dsi->bridge.funcs = &exynos_dsi_bridge_funcs;
dsi->bridge.of_node = dev->of_node;
dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;
+ dsi->bridge.pre_enable_prev_first = true;
ret = component_add(dev, &exynos_dsi_component_ops);
if (ret)
On Exynos5433 Exynos DSI is together with Exynos MIC in the bridge
chain: Decon -> MIC -> DSI -> Panel.
To ensure proper order of initialization we need to mark our bridge
driver also with the pre_enable_prev_first flag. This would also need to
be added to patch "[PATCH v9 06/18] drm: bridge: Generalize Exynos-DSI
driver into a Samsung DSIM bridge".
> drivers/gpu/drm/exynos/exynos_drm_dsi.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> index ec673223d6b7..e5b1540c4ae4 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> @@ -1428,7 +1428,8 @@ static int exynos_dsi_attach(struct drm_bridge *bridge,
> {
> struct exynos_dsi *dsi = bridge_to_dsi(bridge);
>
> - return drm_bridge_attach(bridge->encoder, dsi->out_bridge, NULL, flags);
> + return drm_bridge_attach(bridge->encoder, dsi->out_bridge, bridge,
> + flags);
> }
>
> static const struct drm_bridge_funcs exynos_dsi_bridge_funcs = {
> @@ -1474,7 +1475,10 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host,
>
> drm_bridge_add(&dsi->bridge);
>
> - drm_bridge_attach(encoder, &dsi->bridge, NULL, 0);
> + drm_bridge_attach(encoder, &dsi->bridge,
> + list_first_entry_or_null(&encoder->bridge_chain,
> + struct drm_bridge,
> + chain_node), 0);
>
> /*
> * This is a temporary solution and should be made by more generic way.
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
