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

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>

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 at renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz at renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz at bp.renesas.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
---
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