From:   Javier Martinez Canillas <javierm@redhat.com>
To:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Cc:     Javier Martinez Canillas <javierm@redhat.com>,
        Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Subject: [PATCH 32/60] drm: rcar-du: Add support for the nomodeset kernel parameter
Date:   Wed, 15 Dec 2021 01:59:40 +0100
Message-Id: <20211215010008.2545520-33-javierm@redhat.com>
In-Reply-To: <20211215010008.2545520-1-javierm@redhat.com>
References: <20211215010008.2545520-1-javierm@redhat.com>
MIME-Version: 1.0
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According to disable Documentation/admin-guide/kernel-parameters.txt, this
parameter can be used to disable kernel modesetting.

DRM drivers will not perform display-mode changes or accelerated rendering
and only the systewm system framebuffer will be available if it was set-up.

But only a few DRM drivers currently check for nomodeset, make this driver
to also support the command line parameter.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

 drivers/gpu/drm/rcar-du/rcar_du_drv.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.c b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
index 5612a9e7a905..7b676b2f0f06 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_drv.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
@@ -699,6 +699,9 @@ static struct platform_driver rcar_du_platform_driver = {
 
 static int __init rcar_du_init(void)
 {
+	if (drm_firmware_drivers_only())
+		return -ENODEV;
+
 	rcar_du_of_init(rcar_du_of_table);
 
 	return platform_driver_register(&rcar_du_platform_driver);
-- 
2.33.1