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>,
        Anitha Chrisanthus <anitha.chrisanthus@intel.com>,
        Edmund Dea <edmund.j.dea@intel.com>
Subject: [PATCH 19/60] drm/kmb: Add support for the nomodeset kernel parameter
Date:   Wed, 15 Dec 2021 01:59:27 +0100
Message-Id: <20211215010008.2545520-20-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/kmb/kmb_drv.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/kmb/kmb_drv.c b/drivers/gpu/drm/kmb/kmb_drv.c
index ed2424350773..56a59ee71755 100644
--- a/drivers/gpu/drm/kmb/kmb_drv.c
+++ b/drivers/gpu/drm/kmb/kmb_drv.c
@@ -484,6 +484,9 @@ static int kmb_probe(struct platform_device *pdev)
 	struct device_node *dsi_node;
 	struct platform_device *dsi_pdev;
 
+	if (drm_firmware_drivers_only())
+		return -ENODEV;
+
 	/* The bridge (ADV 7535) will return -EPROBE_DEFER until it
 	 * has a mipi_dsi_host to register its device to. So, we
 	 * first register the DSI host during probe time, and then return
-- 
2.33.1