drm/hisilicon/kirin: Use drm_fbdev_generic_setup()

The CMA helper is already using the drm_fb_helper_generic_probe part of
the generic fbdev emulation. This patch makes full use of the generic
fbdev emulation by using its drm_client callbacks. This means that
drm_mode_config_funcs->output_poll_changed and drm_driver->lastclose are
now handled by the emulation code. Additionally fbdev unregister happens
automatically on drm_dev_unregister().

The drm_fbdev_generic_setup() call is put after drm_dev_register() in the
driver. This is done to highlight the fact that fbdev emulation is an
internal client that makes use of the driver, it is not part of the
driver as such. If fbdev setup fails, an error is printed, but the driver
succeeds probing.

struct kirin_drm_private can be removed now that driver doesn't have to
store the fbdev pointer.

Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Cc: Chen Feng <puck.chen@hisilicon.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20181128212713.43500-2-noralf@tronnes.org

drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c

@@ -22,6 +22,7 @@
 #include <drm/drmP.h>
 #include <drm/drm_gem_cma_helper.h>
 #include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fb_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc_helper.h>
@@ -33,32 +34,15 @@ static struct kirin_dc_ops *dc_ops;
 
 static int kirin_drm_kms_cleanup(struct drm_device *dev)
 {
-	struct kirin_drm_private *priv = dev->dev_private;
-
-	if (priv->fbdev) {
-		drm_fbdev_cma_fini(priv->fbdev);
-		priv->fbdev = NULL;
-	}
-
 	drm_kms_helper_poll_fini(dev);
 	dc_ops->cleanup(to_platform_device(dev->dev));
 	drm_mode_config_cleanup(dev);
-	devm_kfree(dev->dev, priv);
-	dev->dev_private = NULL;
 
 	return 0;
 }
 
-static void kirin_fbdev_output_poll_changed(struct drm_device *dev)
-{
-	struct kirin_drm_private *priv = dev->dev_private;
-
-	drm_fbdev_cma_hotplug_event(priv->fbdev);
-}
-
 static const struct drm_mode_config_funcs kirin_drm_mode_config_funcs = {
 	.fb_create = drm_gem_fb_create,
-	.output_poll_changed = kirin_fbdev_output_poll_changed,
 	.atomic_check = drm_atomic_helper_check,
 	.atomic_commit = drm_atomic_helper_commit,
 };
@@ -76,14 +60,8 @@ static void kirin_drm_mode_config_init(struct drm_device *dev)
 
 static int kirin_drm_kms_init(struct drm_device *dev)
 {
-	struct kirin_drm_private *priv;
 	int ret;
 
-	priv = devm_kzalloc(dev->dev, sizeof(*priv), GFP_KERNEL);
-	if (!priv)
-		return -ENOMEM;
-
-	dev->dev_private = priv;
 	dev_set_drvdata(dev->dev, dev);
 
 	/* dev->mode_config initialization */
@@ -117,26 +95,14 @@ static int kirin_drm_kms_init(struct drm_device *dev)
 	/* init kms poll for handling hpd */
 	drm_kms_helper_poll_init(dev);
 
-	priv->fbdev = drm_fbdev_cma_init(dev, 32,
-					 dev->mode_config.num_connector);
-
-	if (IS_ERR(priv->fbdev)) {
-		DRM_ERROR("failed to initialize fbdev.\n");
-		ret = PTR_ERR(priv->fbdev);
-		goto err_cleanup_poll;
-	}
 	return 0;
 
-err_cleanup_poll:
-	drm_kms_helper_poll_fini(dev);
 err_unbind_all:
 	component_unbind_all(dev->dev, dev);
 err_dc_cleanup:
 	dc_ops->cleanup(to_platform_device(dev->dev));
 err_mode_config_cleanup:
 	drm_mode_config_cleanup(dev);
-	devm_kfree(dev->dev, priv);
-	dev->dev_private = NULL;
 
 	return ret;
 }
@@ -199,6 +165,8 @@ static int kirin_drm_bind(struct device *dev)
 	if (ret)
 		goto err_kms_cleanup;
 
+	drm_fbdev_generic_setup(drm_dev, 32);
+
 	return 0;
 
 err_kms_cleanup:

drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.h

@@ -19,10 +19,6 @@ struct kirin_dc_ops {
 	void (*cleanup)(struct platform_device *pdev);
 };
 
-struct kirin_drm_private {
-	struct drm_fbdev_cma *fbdev;
-};
-
 extern const struct kirin_dc_ops ade_dc_ops;
 
 #endif /* __KIRIN_DRM_DRV_H__ */