Re: [PATCH v5 1/7] drm: sunxi: Add a basic DRM driver for Allwinner DE2

On Tue, Oct 25, 2016 at 08:44:22AM +0200, Daniel Vetter wrote:

On Fri, Oct 21, 2016 at 09:26:18AM +0200, Jean-Francois Moine wrote:

quoted

+static int de2_drm_bind(struct device *dev)
+{
+	struct drm_device *drm;
+	struct priv *priv;
+	int ret;
+
+	drm = drm_dev_alloc(&de2_drm_driver, dev);

Oh and you might want to look into drm_dev_init, allows you to use
subclassing instead of pointer chasing for your driver-private data.
-Daniel

quoted

+	if (!drm)
+		return -ENOMEM;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		dev_err(dev, "failed to allocate private area\n");
+		ret = -ENOMEM;
+		goto out1;
+	}
+
+	dev_set_drvdata(dev, drm);
+	drm->dev_private = priv;
+
+	drm_mode_config_init(drm);
+	drm->mode_config.min_width = 32;	/* needed for cursor */
+	drm->mode_config.min_height = 32;
+	drm->mode_config.max_width = 1920;
+	drm->mode_config.max_height = 1080;
+	drm->mode_config.funcs = &de2_mode_config_funcs;
+
+	drm->irq_enabled = true;
+
+	/* initialize the display engine */
+	priv->soc_type = (int) of_match_device(de2_drm_of_match, dev)->data;
+	ret = de2_de_init(priv, dev);
+	if (ret)
+		goto out2;
+
+	/* start the subdevices */
+	ret = component_bind_all(dev, drm);
+	if (ret < 0)
+		goto out2;
+
+	ret = drm_dev_register(drm, 0);

This needs to be the very last step in your driver load sequence.
Kerneldoc explains why. Similar, but inverted for unloading:
drm_dev_unregister is the very first thing you must call.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
--
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