drm/msm: Add support for the nomodeset kernel parameter

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 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>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211217003752.3946210-30-javierm@redhat.com

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 892c043..8f30e68 100644 (file)
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -518,6 +518,9 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv)
        struct msm_mdss *mdss;
        int ret, i;
 
+       if (drm_firmware_drivers_only())
+               return -ENODEV;
+
        ddev = drm_dev_alloc(drv, dev);
        if (IS_ERR(ddev)) {
                DRM_DEV_ERROR(dev, "failed to allocate drm_device\n");