drm-misc-next for 4.16:

Core Changes:
 - mostly doc updates and some fbdev improvements
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJaO+bMAAoJEEN0HIUfOBk0gVQQAIVnRSqyDRfP/1Erzp8vPtmr
 KKDL4hZsROHY2yzgqOPBbGZDUMUv2RcEl6H/p07VsW8c8Cqu/SgOlx9xlnRz+dEx
 Zjv7G6MjX1hG8dq0Qy2bKYfFJP2/+fx+Kz/lYMVpWvy2trxUJ8uB71cSl/wUWrkH
 iUqhAg/Jq80RADQTNG2j7oVYiRGGlcIGh8zmdIwfQyXRJJK+AHR7KU7g7PFut85u
 Z5fdGSn4Qs6LkKe7VzHrmlp0mpuPWy1bayoLjVGpjmrVYvieXwo/cOHVjCqL1fwU
 H5p4B2LYeBN27ejRyEFXTMCZJr2rbT0OGrlJ9/oghZwM6Of4BF8ZxO9v0yC0czlg
 +GHJsOZO7Y8enUSnGT4OyslGr49VuzYqtleK2QDAV43IImYzfNB7h6xx6qgWKynv
 VEl9zNJ99+WtOe5pZAUrPuumsOSKVbEU2wxmnODNLk1/XInhQ/oCHpFeCU93bqRD
 YR034QyMMev8e3fJe9xUWdfcTdmCFUGhs5wZn0Cu0ywbjTFnGC2WgTT2j3ln0NOQ
 xKUQO16oXkx0R4rJIIH8Z0olwcwfV4SBlWyD9sWAaAtxiWkm3mwj1Fs14zyHOg0C
 uJtCii0Nv4Lissljwk4uYSGNiHzQmu80INUxAhj+x3yR9RDABAm/9AOtK1LBGeL/
 7JRCXlKhZbqZeLZ8zBFt
 =AxYV
 -----END PGP SIGNATURE-----

Merge tag 'drm-misc-next-2017-12-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for 4.16:

Core Changes:
- mostly doc updates and some fbdev improvements

* tag 'drm-misc-next-2017-12-21' of git://anongit.freedesktop.org/drm/drm-misc:
  drm/framebuffer: Print task that allocated the fb in debug info.
  drm/fb-helper: Add drm_fb_helper_defio_init()
  drm/fb-helper: Update DOC with new helpers
  drm/docs: Add todo entry for drm_fb_helper_fbdev_setup()
  drm/fb-helper: Add drm_fb_helper_fbdev_setup/teardown()
  drm/fb-helper: Set/clear dev->fb_helper in dummy init/fini
  drm/stm: ltdc: Remove unnecessary platform_get_resource() error check
  drm/stm: dsi: Remove unnecessary platform_get_resource() error check
  drm/doc: Move legacy kms helpers to the very end
  drm/atomic: document how to handle driver private objects
  drm/syncobj: some kerneldoc polish
  drm/print: Unconfuse kerneldoc
  drm/edid: kerneldoc for is_hdmi2_sink

Documentation/gpu/drm-kms-helpers.rst

@@ -74,15 +74,6 @@ Helper Functions Reference
 .. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
    :export:
 
-Legacy CRTC/Modeset Helper Functions Reference
-==============================================
-
-.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
-   :doc: overview
-
-.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
-   :export:
-
 Simple KMS Helper Reference
 ===========================
 
@@ -282,15 +273,6 @@ Flip-work Helper Reference
 .. kernel-doc:: drivers/gpu/drm/drm_flip_work.c
    :export:
 
-Plane Helper Reference
-======================
-
-.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
-   :doc: overview
-
-.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
-   :export:
-
 Auxiliary Modeset Helpers
 =========================
 
@@ -308,3 +290,21 @@ Framebuffer GEM Helper Reference
 
 .. kernel-doc:: drivers/gpu/drm/drm_gem_framebuffer_helper.c
    :export:
+
+Legacy Plane Helper Reference
+=============================
+
+.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
+   :doc: overview
+
+.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
+   :export:
+
+Legacy CRTC/Modeset Helper Functions Reference
+==============================================
+
+.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
+   :doc: overview
+
+.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
+   :export:

Documentation/gpu/drm-kms.rst

@@ -263,14 +263,20 @@ Taken all together there's two consequences for the atomic design:
 
 - An atomic update is assembled and validated as an entirely free-standing pile
   of structures within the :c:type:`drm_atomic_state <drm_atomic_state>`
-  container. Again drivers can subclass that container for their own state
+  container. Driver private state structures are also tracked in the same
-  structure tracking needs. Only when a state is committed is it applied to the
+  structure; see the next chapter.  Only when a state is committed is it applied
-  driver and modeset objects. This way rolling back an update boils down to
+  to the driver and modeset objects. This way rolling back an update boils down
-  releasing memory and unreferencing objects like framebuffers.
+  to releasing memory and unreferencing objects like framebuffers.
 
 Read on in this chapter, and also in :ref:`drm_atomic_helper` for more detailed
 coverage of specific topics.
 
+Handling Driver Private State
+-----------------------------
+
+.. kernel-doc:: drivers/gpu/drm/drm_atomic.c
+   :doc: handling driver private state
+
 Atomic Mode Setting Function Reference
 --------------------------------------
 

Documentation/gpu/todo.rst

@@ -194,6 +194,24 @@ drm_mode_config_helper_suspend/resume().
 
 Contact: Maintainer of the driver you plan to convert
 
+Convert drivers to use drm_fb_helper_fbdev_setup/teardown()
+-----------------------------------------------------------
+
+Most drivers can use drm_fb_helper_fbdev_setup() except maybe:
+
+- amdgpu which has special logic to decide whether to call
+  drm_helper_disable_unused_functions()
+
+- armada which isn't atomic and doesn't call
+  drm_helper_disable_unused_functions()
+
+- i915 which calls drm_fb_helper_initial_config() in a worker
+
+Drivers that use drm_framebuffer_remove() to clean up the fbdev framebuffer can
+probably use drm_fb_helper_fbdev_teardown().
+
+Contact: Maintainer of the driver you plan to convert
+
 Core refactorings
 =================
 

drivers/gpu/drm/drm_atomic.c

@@ -50,7 +50,8 @@ EXPORT_SYMBOL(__drm_crtc_commit_free);
  * @state: atomic state
  *
  * Free all the memory allocated by drm_atomic_state_init.
- * This is useful for drivers that subclass the atomic state.
+ * This should only be used by drivers which are still subclassing
+ * &drm_atomic_state and haven't switched to &drm_private_state yet.
  */
 void drm_atomic_state_default_release(struct drm_atomic_state *state)
 {
@@ -67,7 +68,8 @@ EXPORT_SYMBOL(drm_atomic_state_default_release);
  * @state: atomic state
  *
  * Default implementation for filling in a new atomic state.
- * This is useful for drivers that subclass the atomic state.
+ * This should only be used by drivers which are still subclassing
+ * &drm_atomic_state and haven't switched to &drm_private_state yet.
  */
 int
 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
@@ -132,7 +134,8 @@ EXPORT_SYMBOL(drm_atomic_state_alloc);
  * @state: atomic state
  *
  * Default implementation for clearing atomic state.
- * This is useful for drivers that subclass the atomic state.
+ * This should only be used by drivers which are still subclassing
+ * &drm_atomic_state and haven't switched to &drm_private_state yet.
  */
 void drm_atomic_state_default_clear(struct drm_atomic_state *state)
 {
@@ -946,6 +949,42 @@ static void drm_atomic_plane_print_state(struct drm_printer *p,
 		plane->funcs->atomic_print_state(p, state);
 }
 
+/**
+ * DOC: handling driver private state
+ *
+ * Very often the DRM objects exposed to userspace in the atomic modeset api
+ * (&drm_connector, &drm_crtc and &drm_plane) do not map neatly to the
+ * underlying hardware. Especially for any kind of shared resources (e.g. shared
+ * clocks, scaler units, bandwidth and fifo limits shared among a group of
+ * planes or CRTCs, and so on) it makes sense to model these as independent
+ * objects. Drivers then need to do similar state tracking and commit ordering for
+ * such private (since not exposed to userpace) objects as the atomic core and
+ * helpers already provide for connectors, planes and CRTCs.
+ *
+ * To make this easier on drivers the atomic core provides some support to track
+ * driver private state objects using struct &drm_private_obj, with the
+ * associated state struct &drm_private_state.
+ *
+ * Similar to userspace-exposed objects, private state structures can be
+ * acquired by calling drm_atomic_get_private_obj_state(). Since this function
+ * does not take care of locking, drivers should wrap it for each type of
+ * private state object they have with the required call to drm_modeset_lock()
+ * for the corresponding &drm_modeset_lock.
+ *
+ * All private state structures contained in a &drm_atomic_state update can be
+ * iterated using for_each_oldnew_private_obj_in_state(),
+ * for_each_new_private_obj_in_state() and for_each_old_private_obj_in_state().
+ * Drivers are recommended to wrap these for each type of driver private state
+ * object they have, filtering on &drm_private_obj.funcs using for_each_if(), at
+ * least if they want to iterate over all objects of a given type.
+ *
+ * An earlier way to handle driver private state was by subclassing struct
+ * &drm_atomic_state. But since that encourages non-standard ways to implement
+ * the check/commit split atomic requires (by using e.g. "check and rollback or
+ * commit instead" of "duplicate state, check, then either commit or release
+ * duplicated state) it is deprecated in favour of using &drm_private_state.
+ */
+
 /**
  * drm_atomic_private_obj_init - initialize private object
  * @obj: private object

drivers/gpu/drm/drm_edid.c

@@ -4871,6 +4871,11 @@ EXPORT_SYMBOL(drm_hdmi_avi_infoframe_from_display_mode);
  * @mode: DRM display mode
  * @rgb_quant_range: RGB quantization range (Q)
  * @rgb_quant_range_selectable: Sink support selectable RGB quantization range (QS)
+ * @is_hdmi2_sink: HDMI 2.0 sink, which has different default recommendations
+ *
+ * Note that @is_hdmi2_sink can be derived by looking at the
+ * &drm_scdc.supported flag stored in &drm_hdmi_info.scdc,
+ * &drm_display_info.hdmi, which can be found in &drm_connector.display_info.
  */
 void
 drm_hdmi_avi_infoframe_quant_range(struct hdmi_avi_infoframe *frame,

drivers/gpu/drm/drm_fb_helper.c

@@ -66,19 +66,23 @@ static DEFINE_MUTEX(kernel_fb_helper_lock);
  * helper functions used by many drivers to implement the kernel mode setting
  * interfaces.
  *
- * Initialization is done as a four-step process with drm_fb_helper_prepare(),
+ * Setup fbdev emulation by calling drm_fb_helper_fbdev_setup() and tear it
- * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
+ * down by calling drm_fb_helper_fbdev_teardown().
- * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
- * default behaviour can override the third step with their own code.
- * Teardown is done with drm_fb_helper_fini() after the fbdev device is
- * unregisters using drm_fb_helper_unregister_fbi().
  *
- * At runtime drivers should restore the fbdev console by calling
+ * Drivers that need to handle connector hotplugging (e.g. dp mst) can't use
- * drm_fb_helper_restore_fbdev_mode_unlocked() from their &drm_driver.lastclose
+ * the setup helper and will need to do the whole four-step setup process with
- * callback.  They should also notify the fb helper code from updates to the
+ * drm_fb_helper_prepare(), drm_fb_helper_init(),
- * output configuration by calling drm_fb_helper_hotplug_event(). For easier
+ * drm_fb_helper_single_add_all_connectors(), enable hotplugging and
- * integration with the output polling code in drm_crtc_helper.c the modeset
+ * drm_fb_helper_initial_config() to avoid a possible race window.
- * code provides a &drm_mode_config_funcs.output_poll_changed callback.
+ *
+ * At runtime drivers should restore the fbdev console by using
+ * drm_fb_helper_lastclose() as their &drm_driver.lastclose callback.
+ * They should also notify the fb helper code from updates to the output
+ * configuration by using drm_fb_helper_output_poll_changed() as their
+ * &drm_mode_config_funcs.output_poll_changed callback.
+ *
+ * For suspend/resume consider using drm_mode_config_helper_suspend() and
+ * drm_mode_config_helper_resume() which takes care of fbdev as well.
  *
  * All other functions exported by the fb helper library can be used to
  * implement the fbdev driver interface by the driver.
@@ -103,7 +107,8 @@ static DEFINE_MUTEX(kernel_fb_helper_lock);
  * always run in process context since the fb_*() function could be running in
  * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io
  * callback it will also schedule dirty_work with the damage collected from the
- * mmap page writes.
+ * mmap page writes. Drivers can use drm_fb_helper_defio_init() to setup
+ * deferred I/O (coupled with drm_fb_helper_fbdev_teardown()).
  */
 
 #define drm_fb_helper_for_each_connector(fbh, i__) \
@@ -1024,6 +1029,49 @@ void drm_fb_helper_deferred_io(struct fb_info *info,
 }
 EXPORT_SYMBOL(drm_fb_helper_deferred_io);
 
+/**
+ * drm_fb_helper_defio_init - fbdev deferred I/O initialization
+ * @fb_helper: driver-allocated fbdev helper
+ *
+ * This function allocates &fb_deferred_io, sets callback to
+ * drm_fb_helper_deferred_io(), delay to 50ms and calls fb_deferred_io_init().
+ * It should be called from the &drm_fb_helper_funcs->fb_probe callback.
+ * drm_fb_helper_fbdev_teardown() cleans up deferred I/O.
+ *
+ * NOTE: A copy of &fb_ops is made and assigned to &info->fbops. This is done
+ * because fb_deferred_io_cleanup() clears &fbops->fb_mmap and would thereby
+ * affect other instances of that &fb_ops.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
+{
+	struct fb_info *info = fb_helper->fbdev;
+	struct fb_deferred_io *fbdefio;
+	struct fb_ops *fbops;
+
+	fbdefio = kzalloc(sizeof(*fbdefio), GFP_KERNEL);
+	fbops = kzalloc(sizeof(*fbops), GFP_KERNEL);
+	if (!fbdefio || !fbops) {
+		kfree(fbdefio);
+		kfree(fbops);
+		return -ENOMEM;
+	}
+
+	info->fbdefio = fbdefio;
+	fbdefio->delay = msecs_to_jiffies(50);
+	fbdefio->deferred_io = drm_fb_helper_deferred_io;
+
+	*fbops = *info->fbops;
+	info->fbops = fbops;
+
+	fb_deferred_io_init(info);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_fb_helper_defio_init);
+
 /**
  * drm_fb_helper_sys_read - wrapper around fb_sys_read
  * @info: fb_info struct pointer
@@ -1848,6 +1896,7 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 	if (ret < 0)
 		return ret;
 
+	strcpy(fb_helper->fb->comm, "[fbcon]");
 	return 0;
 }
 
@@ -2729,6 +2778,120 @@ int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 }
 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
 
+/**
+ * drm_fb_helper_fbdev_setup() - Setup fbdev emulation
+ * @dev: DRM device
+ * @fb_helper: fbdev helper structure to set up
+ * @funcs: fbdev helper functions
+ * @preferred_bpp: Preferred bits per pixel for the device.
+ *                 @dev->mode_config.preferred_depth is used if this is zero.
+ * @max_conn_count: Maximum number of connectors.
+ *                  @dev->mode_config.num_connector is used if this is zero.
+ *
+ * This function sets up fbdev emulation and registers fbdev for access by
+ * userspace. If all connectors are disconnected, setup is deferred to the next
+ * time drm_fb_helper_hotplug_event() is called.
+ * The caller must to provide a &drm_fb_helper_funcs->fb_probe callback
+ * function.
+ *
+ * See also: drm_fb_helper_initial_config()
+ *
+ * Returns:
+ * Zero on success or negative error code on failure.
+ */
+int drm_fb_helper_fbdev_setup(struct drm_device *dev,
+			      struct drm_fb_helper *fb_helper,
+			      const struct drm_fb_helper_funcs *funcs,
+			      unsigned int preferred_bpp,
+			      unsigned int max_conn_count)
+{
+	int ret;
+
+	if (!preferred_bpp)
+		preferred_bpp = dev->mode_config.preferred_depth;
+	if (!preferred_bpp)
+		preferred_bpp = 32;
+
+	if (!max_conn_count)
+		max_conn_count = dev->mode_config.num_connector;
+	if (!max_conn_count) {
+		DRM_DEV_ERROR(dev->dev, "No connectors\n");
+		return -EINVAL;
+	}
+
+	drm_fb_helper_prepare(dev, fb_helper, funcs);
+
+	ret = drm_fb_helper_init(dev, fb_helper, max_conn_count);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev->dev, "Failed to initialize fbdev helper\n");
+		return ret;
+	}
+
+	ret = drm_fb_helper_single_add_all_connectors(fb_helper);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev->dev, "Failed to add connectors\n");
+		goto err_drm_fb_helper_fini;
+	}
+
+	if (!drm_drv_uses_atomic_modeset(dev))
+		drm_helper_disable_unused_functions(dev);
+
+	ret = drm_fb_helper_initial_config(fb_helper, preferred_bpp);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev->dev, "Failed to set fbdev configuration\n");
+		goto err_drm_fb_helper_fini;
+	}
+
+	return 0;
+
+err_drm_fb_helper_fini:
+	drm_fb_helper_fini(fb_helper);
+
+	return ret;
+}
+EXPORT_SYMBOL(drm_fb_helper_fbdev_setup);
+
+/**
+ * drm_fb_helper_fbdev_teardown - Tear down fbdev emulation
+ * @dev: DRM device
+ *
+ * This function unregisters fbdev if not already done and cleans up the
+ * associated resources including the &drm_framebuffer.
+ * The driver is responsible for freeing the &drm_fb_helper structure which is
+ * stored in &drm_device->fb_helper. Do note that this pointer has been cleared
+ * when this function returns.
+ *
+ * In order to support device removal/unplug while file handles are still open,
+ * drm_fb_helper_unregister_fbi() should be called on device removal and
+ * drm_fb_helper_fbdev_teardown() in the &drm_driver->release callback when
+ * file handles are closed.
+ */
+void drm_fb_helper_fbdev_teardown(struct drm_device *dev)
+{
+	struct drm_fb_helper *fb_helper = dev->fb_helper;
+	struct fb_ops *fbops = NULL;
+
+	if (!fb_helper)
+		return;
+
+	/* Unregister if it hasn't been done already */
+	if (fb_helper->fbdev && fb_helper->fbdev->dev)
+		drm_fb_helper_unregister_fbi(fb_helper);
+
+	if (fb_helper->fbdev && fb_helper->fbdev->fbdefio) {
+		fb_deferred_io_cleanup(fb_helper->fbdev);
+		kfree(fb_helper->fbdev->fbdefio);
+		fbops = fb_helper->fbdev->fbops;
+	}
+
+	drm_fb_helper_fini(fb_helper);
+	kfree(fbops);
+
+	if (fb_helper->fb)
+		drm_framebuffer_remove(fb_helper->fb);
+}
+EXPORT_SYMBOL(drm_fb_helper_fbdev_teardown);
+
 /**
  * drm_fb_helper_lastclose - DRM driver lastclose helper for fbdev emulation
  * @dev: DRM device

drivers/gpu/drm/drm_framebuffer.c

@@ -664,6 +664,7 @@ int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
 	INIT_LIST_HEAD(&fb->filp_head);
 
 	fb->funcs = funcs;
+	strcpy(fb->comm, current->comm);
 
 	ret = __drm_mode_object_add(dev, &fb->base, DRM_MODE_OBJECT_FB,
 				    false, drm_framebuffer_free);
@@ -978,6 +979,7 @@ void drm_framebuffer_print_info(struct drm_printer *p, unsigned int indent,
 	struct drm_format_name_buf format_name;
 	unsigned int i;
 
+	drm_printf_indent(p, indent, "allocated by = %s\n", fb->comm);
 	drm_printf_indent(p, indent, "refcount=%u\n",
 			  drm_framebuffer_read_refcount(fb));
 	drm_printf_indent(p, indent, "format=%s\n",

drivers/gpu/drm/drm_syncobj.c

@@ -29,9 +29,9 @@
 /**
  * DOC: Overview
  *
- * DRM synchronisation objects (syncobj) are a persistent objects,
+ * DRM synchronisation objects (syncobj, see struct &drm_syncobj) are
- * that contain an optional fence. The fence can be updated with a new
+ * persistent objects that contain an optional fence. The fence can be updated
- * fence, or be NULL.
+ * with a new fence, or be NULL.
  *
  * syncobj's can be waited upon, where it will wait for the underlying
  * fence.
@@ -61,7 +61,8 @@
  * @file_private: drm file private pointer
  * @handle: sync object handle to lookup.
  *
- * Returns a reference to the syncobj pointed to by handle or NULL.
+ * Returns a reference to the syncobj pointed to by handle or NULL. The
+ * reference must be released by calling drm_syncobj_put().
  */
 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
 				     u32 handle)
@@ -229,6 +230,19 @@ static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
 	return 0;
 }
 
+/**
+ * drm_syncobj_find_fence - lookup and reference the fence in a sync object
+ * @file_private: drm file private pointer
+ * @handle: sync object handle to lookup.
+ * @fence: out parameter for the fence
+ *
+ * This is just a convenience function that combines drm_syncobj_find() and
+ * drm_syncobj_fence_get().
+ *
+ * Returns 0 on success or a negative error value on failure. On success @fence
+ * contains a reference to the fence, which must be released by calling
+ * dma_fence_put().
+ */
 int drm_syncobj_find_fence(struct drm_file *file_private,
 			   u32 handle,
 			   struct dma_fence **fence)
@@ -269,6 +283,12 @@ EXPORT_SYMBOL(drm_syncobj_free);
  * @out_syncobj: returned syncobj
  * @flags: DRM_SYNCOBJ_* flags
  * @fence: if non-NULL, the syncobj will represent this fence
+ *
+ * This is the first function to create a sync object. After creating, drivers
+ * probably want to make it available to userspace, either through
+ * drm_syncobj_get_handle() or drm_syncobj_get_fd().
+ *
+ * Returns 0 on success or a negative error value on failure.
  */
 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 		       struct dma_fence *fence)
@@ -302,6 +322,14 @@ EXPORT_SYMBOL(drm_syncobj_create);
 
 /**
  * drm_syncobj_get_handle - get a handle from a syncobj
+ * @file_private: drm file private pointer
+ * @syncobj: Sync object to export
+ * @handle: out parameter with the new handle
+ *
+ * Exports a sync object created with drm_syncobj_create() as a handle on
+ * @file_private to userspace.
+ *
+ * Returns 0 on success or a negative error value on failure.
  */
 int drm_syncobj_get_handle(struct drm_file *file_private,
 			   struct drm_syncobj *syncobj, u32 *handle)
@@ -388,6 +416,15 @@ static int drm_syncobj_alloc_file(struct drm_syncobj *syncobj)
 	return 0;
 }
 
+/**
+ * drm_syncobj_get_fd - get a file descriptor from a syncobj
+ * @syncobj: Sync object to export
+ * @p_fd: out parameter with the new file descriptor
+ *
+ * Exports a sync object created with drm_syncobj_create() as a file descriptor.
+ *
+ * Returns 0 on success or a negative error value on failure.
+ */
 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
 {
 	int ret;

drivers/gpu/drm/stm/dw_mipi_dsi-stm.c

@@ -290,11 +290,6 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		DRM_ERROR("Unable to get resource\n");
-		return -ENODEV;
-	}
-
 	dsi->base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(dsi->base)) {
 		DRM_ERROR("Unable to get dsi registers\n");

drivers/gpu/drm/stm/ltdc.c

@@ -901,12 +901,6 @@ int ltdc_load(struct drm_device *ddev)
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		DRM_ERROR("Unable to get resource\n");
-		ret = -ENODEV;
-		goto err;
-	}
-
 	ldev->regs = devm_ioremap_resource(dev, res);
 	if (IS_ERR(ldev->regs)) {
 		DRM_ERROR("Unable to get ltdc registers\n");

include/drm/drm_atomic.h

@@ -189,12 +189,40 @@ struct drm_private_state_funcs {
 				     struct drm_private_state *state);
 };
 
+/**
+ * struct drm_private_obj - base struct for driver private atomic object
+ *
+ * A driver private object is initialized by calling
+ * drm_atomic_private_obj_init() and cleaned up by calling
+ * drm_atomic_private_obj_fini().
+ *
+ * Currently only tracks the state update functions and the opaque driver
+ * private state itself, but in the future might also track which
+ * &drm_modeset_lock is required to duplicate and update this object's state.
+ */
 struct drm_private_obj {
+	/**
+	 * @state: Current atomic state for this driver private object.
+	 */
 	struct drm_private_state *state;
 
+	/**
+	 * @funcs:
+	 *
+	 * Functions to manipulate the state of this driver private object, see
+	 * &drm_private_state_funcs.
+	 */
 	const struct drm_private_state_funcs *funcs;
 };
 
+/**
+ * struct drm_private_state - base struct for driver private object state
+ * @state: backpointer to global drm_atomic_state
+ *
+ * Currently only contains a backpointer to the overall atomic update, but in
+ * the future also might hold synchronization information similar to e.g.
+ * &drm_crtc.commit.
+ */
 struct drm_private_state {
 	struct drm_atomic_state *state;
 };
@@ -218,6 +246,10 @@ struct __drm_private_objs_state {
  * @num_private_objs: size of the @private_objs array
  * @private_objs: pointer to array of private object pointers
  * @acquire_ctx: acquire context for this atomic modeset state update
+ *
+ * States are added to an atomic update by calling drm_atomic_get_crtc_state(),
+ * drm_atomic_get_plane_state(), drm_atomic_get_connector_state(), or for
+ * private state structures, drm_atomic_get_private_obj_state().
  */
 struct drm_atomic_state {
 	struct kref ref;

include/drm/drm_fb_helper.h

@@ -33,6 +33,7 @@
 struct drm_fb_helper;
 
 #include <drm/drm_crtc.h>
+#include <drm/drm_device.h>
 #include <linux/kgdb.h>
 
 enum mode_set_atomic {
@@ -275,6 +276,7 @@ void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper);
 
 void drm_fb_helper_deferred_io(struct fb_info *info,
 			       struct list_head *pagelist);
+int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper);
 
 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
 			       size_t count, loff_t *ppos);
@@ -319,6 +321,13 @@ int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_
 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 				       struct drm_connector *connector);
 
+int drm_fb_helper_fbdev_setup(struct drm_device *dev,
+			      struct drm_fb_helper *fb_helper,
+			      const struct drm_fb_helper_funcs *funcs,
+			      unsigned int preferred_bpp,
+			      unsigned int max_conn_count);
+void drm_fb_helper_fbdev_teardown(struct drm_device *dev);
+
 void drm_fb_helper_lastclose(struct drm_device *dev);
 void drm_fb_helper_output_poll_changed(struct drm_device *dev);
 #else
@@ -332,11 +341,17 @@ static inline int drm_fb_helper_init(struct drm_device *dev,
 		       struct drm_fb_helper *helper,
 		       int max_conn)
 {
+	/* So drivers can use it to free the struct */
+	helper->dev = dev;
+	dev->fb_helper = helper;
+
 	return 0;
 }
 
 static inline void drm_fb_helper_fini(struct drm_fb_helper *helper)
 {
+	if (helper && helper->dev)
+		helper->dev->fb_helper = NULL;
 }
 
 static inline int drm_fb_helper_blank(int blank, struct fb_info *info)
@@ -409,6 +424,11 @@ static inline void drm_fb_helper_deferred_io(struct fb_info *info,
 {
 }
 
+static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper)
+{
+	return -ENODEV;
+}
+
 static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info,
 					     char __user *buf, size_t count,
 					     loff_t *ppos)
@@ -518,6 +538,24 @@ drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 	return 0;
 }
 
+static inline int
+drm_fb_helper_fbdev_setup(struct drm_device *dev,
+			  struct drm_fb_helper *fb_helper,
+			  const struct drm_fb_helper_funcs *funcs,
+			  unsigned int preferred_bpp,
+			  unsigned int max_conn_count)
+{
+	/* So drivers can use it to free the struct */
+	dev->fb_helper = fb_helper;
+
+	return 0;
+}
+
+static inline void drm_fb_helper_fbdev_teardown(struct drm_device *dev)
+{
+	dev->fb_helper = NULL;
+}
+
 static inline void drm_fb_helper_lastclose(struct drm_device *dev)
 {
 }

include/drm/drm_framebuffer.h

@@ -121,6 +121,12 @@ struct drm_framebuffer {
 	 * @base: base modeset object structure, contains the reference count.
 	 */
 	struct drm_mode_object base;
+
+	/**
+	 * @comm: Name of the process allocating the fb, used for fb dumping.
+	 */
+	char comm[TASK_COMM_LEN];
+
 	/**
 	 * @format: framebuffer format information
 	 */

include/drm/drm_mode_config.h

@@ -269,6 +269,9 @@ struct drm_mode_config_funcs {
 	 * state easily. If this hook is implemented, drivers must also
 	 * implement @atomic_state_clear and @atomic_state_free.
 	 *
+	 * Subclassing of &drm_atomic_state is deprecated in favour of using
+	 * &drm_private_state and &drm_private_obj.
+	 *
 	 * RETURNS:
 	 *
 	 * A new &drm_atomic_state on success or NULL on failure.
@@ -290,6 +293,9 @@ struct drm_mode_config_funcs {
 	 *
 	 * Drivers that implement this must call drm_atomic_state_default_clear()
 	 * to clear common state.
+	 *
+	 * Subclassing of &drm_atomic_state is deprecated in favour of using
+	 * &drm_private_state and &drm_private_obj.
 	 */
 	void (*atomic_state_clear)(struct drm_atomic_state *state);
 
@@ -302,6 +308,9 @@ struct drm_mode_config_funcs {
 	 *
 	 * Drivers that implement this must call
 	 * drm_atomic_state_default_release() to release common resources.
+	 *
+	 * Subclassing of &drm_atomic_state is deprecated in favour of using
+	 * &drm_private_state and &drm_private_obj.
 	 */
 	void (*atomic_state_free)(struct drm_atomic_state *state);
 };

include/drm/drm_print.h

@@ -80,13 +80,13 @@ void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf);
 __printf(2, 3)
 void drm_printf(struct drm_printer *p, const char *f, ...);
 
+__printf(2, 0)
 /**
  * drm_vprintf - print to a &drm_printer stream
  * @p: the &drm_printer
  * @fmt: format string
  * @va: the va_list
  */
-__printf(2, 0)
 static inline void
 drm_vprintf(struct drm_printer *p, const char *fmt, va_list *va)
 {

include/drm/drm_syncobj.h

@@ -33,36 +33,31 @@ struct drm_syncobj_cb;
 /**
  * struct drm_syncobj - sync object.
  *
- * This structure defines a generic sync object which wraps a dma fence.
+ * This structure defines a generic sync object which wraps a &dma_fence.
  */
 struct drm_syncobj {
 	/**
-	 * @refcount:
+	 * @refcount: Reference count of this object.
-	 *
-	 * Reference count of this object.
 	 */
 	struct kref refcount;
 	/**
 	 * @fence:
 	 * NULL or a pointer to the fence bound to this object.
 	 *
-	 * This field should not be used directly.  Use drm_syncobj_fence_get
+	 * This field should not be used directly. Use drm_syncobj_fence_get()
-	 * and drm_syncobj_replace_fence instead.
+	 * and drm_syncobj_replace_fence() instead.
 	 */
 	struct dma_fence __rcu *fence;
 	/**
-	 * @cb_list:
+	 * @cb_list: List of callbacks to call when the &fence gets replaced.
-	 * List of callbacks to call when the fence gets replaced
 	 */
 	struct list_head cb_list;
 	/**
-	 * @lock:
+	 * @lock: Protects &cb_list and write-locks &fence.
-	 * locks cb_list and write-locks fence.
 	 */
 	spinlock_t lock;
 	/**
-	 * @file:
+	 * @file: A file backing for this syncobj.
-	 * a file backing for this syncobj.
 	 */
 	struct file *file;
 };
@@ -73,7 +68,7 @@ typedef void (*drm_syncobj_func_t)(struct drm_syncobj *syncobj,
 /**
  * struct drm_syncobj_cb - callback for drm_syncobj_add_callback
  * @node: used by drm_syncob_add_callback to append this struct to
- *	  syncobj::cb_list
+ *	  &drm_syncobj.cb_list
  * @func: drm_syncobj_func_t to call
  *
  * This struct will be initialized by drm_syncobj_add_callback, additional
@@ -92,7 +87,7 @@ void drm_syncobj_free(struct kref *kref);
  * drm_syncobj_get - acquire a syncobj reference
  * @obj: sync object
  *
- * This acquires additional reference to @obj. It is illegal to call this
+ * This acquires an additional reference to @obj. It is illegal to call this
  * without already holding a reference. No locks required.
  */
 static inline void
@@ -111,6 +106,17 @@ drm_syncobj_put(struct drm_syncobj *obj)
 	kref_put(&obj->refcount, drm_syncobj_free);
 }
 
+/**
+ * drm_syncobj_fence_get - get a reference to a fence in a sync object
+ * @syncobj: sync object.
+ *
+ * This acquires additional reference to &drm_syncobj.fence contained in @obj,
+ * if not NULL. It is illegal to call this without already holding a reference.
+ * No locks required.
+ *
+ * Returns:
+ * Either the fence of @obj or NULL if there's none.
+ */
 static inline struct dma_fence *
 drm_syncobj_fence_get(struct drm_syncobj *syncobj)
 {