drm/vc4: Fix handling of a pm_runtime_get_sync() success case.

If the device was already up, a 1 is returned instead of 0.  We were
erroring out, leading the 3D driver to sometimes fail at screen
initialization (generally with ENOENT returned to it).

Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: af713795c59f ("drm/vc4: Add a getparam ioctl for getting the V3D identity regs.")

diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 8b42d31a7f0e8b61ed776200841285d7d5687dbb..9ecef93854914579ee74b4d96432d15dfaa1fd6b 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -57,21 +57,21 @@ static int vc4_get_param_ioctl(struct drm_device *dev, void *data,
        switch (args->param) {
        case DRM_VC4_PARAM_V3D_IDENT0:
                ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
-               if (ret)
+               if (ret < 0)
                        return ret;
                args->value = V3D_READ(V3D_IDENT0);
                pm_runtime_put(&vc4->v3d->pdev->dev);
                break;
        case DRM_VC4_PARAM_V3D_IDENT1:
                ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
-               if (ret)
+               if (ret < 0)
                        return ret;
                args->value = V3D_READ(V3D_IDENT1);
                pm_runtime_put(&vc4->v3d->pdev->dev);
                break;
        case DRM_VC4_PARAM_V3D_IDENT2:
                ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);
-               if (ret)
+               if (ret < 0)
                        return ret;
                args->value = V3D_READ(V3D_IDENT2);
                pm_runtime_put(&vc4->v3d->pdev->dev);