Re: [alsa-devel] [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:

...

+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

...

• 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