Hi,
On 03/07/2026 00:24, Laurent Pinchart wrote:
Hi Tomi,
Thank you for the patch.
On Mon, Jun 15, 2026 at 04:11:57PM +0300, Tomi Valkeinen wrote:
Enabling DSI clocks on rcar-du needs some tricks as the DU dot clock is
provided by the DSI. Thus, we call rcar_mipi_dsi_pclk_enable() from the
crtc, when enabling the crtc.
With DSC (added in upcoming patch) in the pipeline, between the DU and
the DSI, the above call path is broken as the crtc tries to call
rcar_mipi_dsi_pclk_enable() on the DSC.
To solve this problem, make sure we store the DSI bridge to the
rcdu->dsi[] array, instead of the first bridge in the DSI pipeline
(which can be DCS), by checking the bridge's bridge->type.
Signed-off-by: Tomi Valkeinen <[email protected]>
---
drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c | 18 ++++++++++++++++--
drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c | 1 +
2 files changed, 17 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c
b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c
index db2088529b48..ac85838ab3b8 100644
--- a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c
+++ b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c
@@ -89,9 +89,23 @@ int rcar_du_encoder_init(struct rcar_du_device *rcdu,
drm_bridge_get(bridge);
if (output == RCAR_DU_OUTPUT_DSI0 ||
- output == RCAR_DU_OUTPUT_DSI1)
+ output == RCAR_DU_OUTPUT_DSI1) {
+ struct drm_bridge *dsi_bridge;
+
+ /*
+ * When we have a DSC block between the DU and the DSI,
+ * the "bridge" points to the DSC. Detect the DSC by
looking
+ * at the bridge type, and skip the DSC if the bridge
is not
+ * the DSI bridge.
+ */
+
+ dsi_bridge = bridge->type == DRM_MODE_CONNECTOR_DSI ?
+ bridge :
+ bridge->next_bridge;
The indentation looks weird.
dsi_bridge = bridge->type == DRM_MODE_CONNECTOR_DSI
? bridge : bridge->next_bridge;
That looks even weirder, you are associating = and ? there. What about:
dsi_bridge = bridge->type == DRM_MODE_CONNECTOR_DSI ?
bridge : bridge->next_bridge;
Tomi
