[PATCH v3 1/9] drm/tests: Stop using deprecated dev_private member on drm_framebuffer tests

[Carlos Eduardo Gallo Filho <gcarlos@xxxxxxxxxxx>]

The dev_private member of drm_device is deprecated and its use should
be avoided. Stop using it by embedding the drm_device onto a mock struct.

The new mock struct allows to share variables and even further mocks
over the tests in a cleaner way than using dev_private void pointer.

Also start using drm_kunit_helper_alloc_drm_device() for allocating
the drm_device mock.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@xxxxxxxxxxx>
---
v2:
  - Start using drm_kunit_helper_alloc_drm_device() for drm_device mock.
  - Rename struct drm_mock to drm_framebuffer_test_priv
v3:
  - Replace the use of void pointer on drm_framebuffer_test_priv struct.
  - Document struct drm_framebuffer_test_priv here.
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 54 ++++++++++++++------
 1 file changed, 38 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 06f03b78c9c4..3882a88b6631 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -8,8 +8,10 @@
 #include <kunit/test.h>
 
 #include <drm/drm_device.h>
+#include <drm/drm_drv.h>
 #include <drm/drm_mode.h>
 #include <drm/drm_fourcc.h>
+#include <drm/drm_kunit_helpers.h>
 #include <drm/drm_print.h>
 
 #include "../drm_crtc_internal.h"
@@ -317,12 +319,25 @@ static const struct drm_framebuffer_test drm_framebuffer_create_cases[] = {
 },
 };
 
+/*
+ * This struct is intended to provide a way to mocked functions communicate
+ * with the outer test when it can't be achieved by using its return value. In
+ * this way, the functions that receive the mocked drm_device, for example, can
+ * grab a reference to this and actually return something to be used on some
+ * expectation.
+ */
+struct drm_framebuffer_test_priv {
+	struct drm_device dev;
+	bool buffer_created;
+};
+
 static struct drm_framebuffer *fb_create_mock(struct drm_device *dev,
 					      struct drm_file *file_priv,
 					      const struct drm_mode_fb_cmd2 *mode_cmd)
 {
-	int *buffer_created = dev->dev_private;
-	*buffer_created = 1;
+	struct drm_framebuffer_test_priv *priv = container_of(dev, typeof(*priv), dev);
+
+	priv->buffer_created = true;
 	return ERR_PTR(-EINVAL);
 }
 
@@ -332,30 +347,37 @@ static struct drm_mode_config_funcs mock_config_funcs = {
 
 static int drm_framebuffer_test_init(struct kunit *test)
 {
-	struct drm_device *mock;
+	struct device *parent;
+	struct drm_framebuffer_test_priv *priv;
+	struct drm_device *dev;
+
+	parent = drm_kunit_helper_alloc_device(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, parent);
 
-	mock = kunit_kzalloc(test, sizeof(*mock), GFP_KERNEL);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, mock);
+	priv = drm_kunit_helper_alloc_drm_device(test, parent, typeof(*priv),
+						 dev, 0);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv);
+	dev = &priv->dev;
 
-	mock->mode_config.min_width = MIN_WIDTH;
-	mock->mode_config.max_width = MAX_WIDTH;
-	mock->mode_config.min_height = MIN_HEIGHT;
-	mock->mode_config.max_height = MAX_HEIGHT;
-	mock->mode_config.funcs = &mock_config_funcs;
+	dev->mode_config.min_width = MIN_WIDTH;
+	dev->mode_config.max_width = MAX_WIDTH;
+	dev->mode_config.min_height = MIN_HEIGHT;
+	dev->mode_config.max_height = MAX_HEIGHT;
+	dev->mode_config.funcs = &mock_config_funcs;
 
-	test->priv = mock;
+	test->priv = priv;
 	return 0;
 }
 
 static void drm_test_framebuffer_create(struct kunit *test)
 {
 	const struct drm_framebuffer_test *params = test->param_value;
-	struct drm_device *mock = test->priv;
-	int buffer_created = 0;
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
 
-	mock->dev_private = &buffer_created;
-	drm_internal_framebuffer_create(mock, &params->cmd, NULL);
-	KUNIT_EXPECT_EQ(test, params->buffer_created, buffer_created);
+	priv->buffer_created = false;
+	drm_internal_framebuffer_create(dev, &params->cmd, NULL);
+	KUNIT_EXPECT_EQ(test, params->buffer_created, priv->buffer_created);
 }
 
 static void drm_framebuffer_test_to_desc(const struct drm_framebuffer_test *t, char *desc)
-- 
2.44.2