[PATCH v7 5/9] drm: renesas: rz-du: mipi_dsi: Make "rst" reset control optional for RZ/V2H(P)

From: Prabhakar
Date: Mon Jun 09 2025 - 18:58:26 EST


From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

In preparation for adding support for the Renesas RZ/V2H(P) SoC, make the
"rst" reset control optional in the MIPI DSI driver. The RZ/V2H(P) SoC
does not provide this reset line, and attempting to acquire it using the
mandatory API causes probe failure.

Switching to devm_reset_control_get_optional_exclusive() ensures
compatibility with both SoCs that provide this reset line and those that
do not, such as RZ/V2H(P).

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
v6->v7:
- No changes

v5->v6:
- Added reviewed tag from Biju and Laurent

v4->v5:
- New patch
---
drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index 85074e0c3cc4..d4f2867e0c5f 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -937,7 +937,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
if (IS_ERR(dsi->vclk))
return PTR_ERR(dsi->vclk);

- dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
+ dsi->rstc = devm_reset_control_get_optional_exclusive(dsi->dev, "rst");
if (IS_ERR(dsi->rstc))
return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
"failed to get rst\n");
--
2.49.0