[PATCH 05/44] drm/vkms: Use devm_drm_dev_alloc

[Daniel Vetter]

This means we also need to slightly restructure the exit code, so that
final cleanup of the drm_device is triggered by unregistering the
platform device. Note that devres is both clean up when the driver is
unbound (not the case for vkms, we don't bind), and also when unregistering
the device (very much the case for vkms). Therefore we can rely on devres
even though vkms isn't a proper platform device driver.

This also somewhat untangles the load code, since the drm and platform device
setup are no longer interleaved, but two distinct steps.

Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
Cc: Rodrigo Siqueira <rodrigosiqueiramelo at gmail.com>
Cc: Haneen Mohammed <hamohammed.sa at gmail.com>
Cc: Daniel Vetter <daniel at ffwll.ch>
---
 drivers/gpu/drm/vkms/vkms_drv.c | 48 +++++++++++----------------------
 1 file changed, 16 insertions(+), 32 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
index eef85f1a0ce5..fec2a4b91c4d 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.c
+++ b/drivers/gpu/drm/vkms/vkms_drv.c
@@ -61,9 +61,6 @@ static void vkms_release(struct drm_device *dev)
 {
 	struct vkms_device *vkms = container_of(dev, struct vkms_device, drm);
 
-	platform_device_unregister(vkms->platform);
-	drm_atomic_helper_shutdown(&vkms->drm);
-	drm_mode_config_cleanup(&vkms->drm);
 	destroy_workqueue(vkms->output.composer_workq);
 }
 
@@ -142,30 +139,26 @@ static int vkms_modeset_init(struct vkms_device *vkmsdev)
 static int __init vkms_init(void)
 {
 	int ret;
+	struct platform_device *pdev;
 
-	vkms_device = kzalloc(sizeof(*vkms_device), GFP_KERNEL);
-	if (!vkms_device)
-		return -ENOMEM;
+	pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
 
-	vkms_device->platform =
-		platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
-	if (IS_ERR(vkms_device->platform)) {
-		ret = PTR_ERR(vkms_device->platform);
-		goto out_free;
+	vkms_device = devm_drm_dev_alloc(&pdev->dev, &vkms_driver,
+					 struct vkms_device, drm);
+	if (IS_ERR(vkms_device)) {
+		platform_device_unregister(pdev);
+		return PTR_ERR(vkms_device);
 	}
-
-	ret = drm_dev_init(&vkms_device->drm, &vkms_driver,
-			   &vkms_device->platform->dev);
-	if (ret)
-		goto out_unregister;
-	drmm_add_final_kfree(&vkms_device->drm, vkms_device);
+	vkms_device->platform = pdev;
 
 	ret = dma_coerce_mask_and_coherent(vkms_device->drm.dev,
 					   DMA_BIT_MASK(64));
 
 	if (ret) {
 		DRM_ERROR("Could not initialize DMA support\n");
-		goto out_put;
+		return ret;
 	}
 
 	vkms_device->drm.irq_enabled = true;
@@ -173,28 +166,18 @@ static int __init vkms_init(void)
 	ret = drm_vblank_init(&vkms_device->drm, 1);
 	if (ret) {
 		DRM_ERROR("Failed to vblank\n");
-		goto out_put;
+		return ret;
 	}
 
 	ret = vkms_modeset_init(vkms_device);
 	if (ret)
-		goto out_put;
+		return ret;
 
 	ret = drm_dev_register(&vkms_device->drm, 0);
 	if (ret)
-		goto out_put;
+		return ret;
 
 	return 0;
-
-out_put:
-	drm_dev_put(&vkms_device->drm);
-	return ret;
-
-out_unregister:
-	platform_device_unregister(vkms_device->platform);
-out_free:
-	kfree(vkms_device);
-	return ret;
 }
 
 static void __exit vkms_exit(void)
@@ -205,7 +188,8 @@ static void __exit vkms_exit(void)
 	}
 
 	drm_dev_unregister(&vkms_device->drm);
-	drm_dev_put(&vkms_device->drm);
+	drm_atomic_helper_shutdown(&vkms_device->drm);
+	platform_device_unregister(vkms_device->platform);
 }
 
 module_init(vkms_init);
-- 
2.25.1