Merge tag 'drm-misc-next-2016-12-08' of git://anongit.freedesktop.org/git/drm-misc into drm-next

Another pile of misc stuff, final one for 4.10. If there's some serious
bugfix still I'll send you a pull for drm-misc-next-fixes (like we do with
intel), otherwise this is it and next pull next year for 4.11.

Most interesting bits are probably Chris' fb helper fixes against mst
hotplug oopses.

* tag 'drm-misc-next-2016-12-08' of git://anongit.freedesktop.org/git/drm-misc: (22 commits)
  drm: Take ownership of the dmabuf->obj when exporting
  drm: Allow CAP_PRIME on !MODESET
  drm/fence: add drm_crtc_create_fence()
  drm/bridge: analogix: Don't return -EINVAL when panel doesn't support PSR
  drm/atomic: doc: remove old comment about nonblocking commits
  drm: Don't block the kworker waiting for mode_config.mutex in output_poll()
  drm: Return -ENOTSUPP when called for KMS cap with a non-KMS driver
  drm/amdgpu: don't add files at control minor debugfs directory
  drm: allow changing DPMS mode
  drm/qxl: fix use of uninitialized variable
  drm/qxl: Don't register debugfs for control minors
  drm/radeon: don't add files at control minor debugfs directory
  drm/vmwgfx: Switch to mode_cmd2
  drm/vgem: Use ww_mutex_(un)lock even with a NULL context
  drm: Make the connector .detect() callback optional
  drm/bridge: tc358767: don't warn if display side ASSR enable fails
  drm: Initialise drm_mm.head_node.allocated
  drm: Fix locking cargo-cult in encoder/plane init/cleanup
  drm/doc: Fix indenting in drm_modeset_lock.c comment
  drm: Protect fb_helper list manipulation with a mutex
  ...

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -2498,9 +2498,6 @@ int amdgpu_debugfs_add_files(struct amdgpu_device *adev,
 	adev->debugfs[adev->debugfs_count].num_files = nfiles;
 	adev->debugfs_count = i;
 #if defined(CONFIG_DEBUG_FS)
-	drm_debugfs_create_files(files, nfiles,
-				 adev->ddev->control->debugfs_root,
-				 adev->ddev->control);
 	drm_debugfs_create_files(files, nfiles,
 				 adev->ddev->primary->debugfs_root,
 				 adev->ddev->primary);
@@ -2514,9 +2511,6 @@ static void amdgpu_debugfs_remove_files(struct amdgpu_device *adev)
 	unsigned i;
 
 	for (i = 0; i < adev->debugfs_count; i++) {
-		drm_debugfs_remove_files(adev->debugfs[i].files,
-					 adev->debugfs[i].num_files,
-					 adev->ddev->control);
 		drm_debugfs_remove_files(adev->debugfs[i].files,
 					 adev->debugfs[i].num_files,
 					 adev->ddev->primary);

drivers/gpu/drm/amd/amdgpu/dce_virtual.c

@@ -424,12 +424,6 @@ dce_virtual_dpms(struct drm_connector *connector, int mode)
 	return 0;
 }
 
-static enum drm_connector_status
-dce_virtual_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static int
 dce_virtual_set_property(struct drm_connector *connector,
 			 struct drm_property *property,
@@ -458,7 +452,6 @@ static const struct drm_connector_helper_funcs dce_virtual_connector_helper_func
 
 static const struct drm_connector_funcs dce_virtual_connector_funcs = {
 	.dpms = dce_virtual_dpms,
-	.detect = dce_virtual_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.set_property = dce_virtual_set_property,
 	.destroy = dce_virtual_destroy,

drivers/gpu/drm/arc/arcpgu_sim.c

@@ -41,12 +41,6 @@ static int arcpgu_drm_connector_get_modes(struct drm_connector *connector)
 	return count;
 }
 
-static enum drm_connector_status
-arcpgu_drm_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void arcpgu_drm_connector_destroy(struct drm_connector *connector)
 {
 	drm_connector_unregister(connector);
@@ -61,7 +55,6 @@ arcpgu_drm_connector_helper_funcs = {
 static const struct drm_connector_funcs arcpgu_drm_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
 	.reset = drm_atomic_helper_connector_reset,
-	.detect = arcpgu_drm_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = arcpgu_drm_connector_destroy,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/ast/ast_mode.c

@@ -839,12 +839,6 @@ static void ast_connector_destroy(struct drm_connector *connector)
 	kfree(connector);
 }
 
-static enum drm_connector_status
-ast_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_helper_funcs ast_connector_helper_funcs = {
 	.mode_valid = ast_mode_valid,
 	.get_modes = ast_get_modes,
@@ -853,7 +847,6 @@ static const struct drm_connector_helper_funcs ast_connector_helper_funcs = {
 
 static const struct drm_connector_funcs ast_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = ast_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = ast_connector_destroy,
 };

drivers/gpu/drm/bochs/bochs_kms.c

@@ -216,12 +216,6 @@ bochs_connector_best_encoder(struct drm_connector *connector)
 	return NULL;
 }
 
-static enum drm_connector_status bochs_connector_detect(struct drm_connector
-							*connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_helper_funcs bochs_connector_connector_helper_funcs = {
 	.get_modes = bochs_connector_get_modes,
 	.mode_valid = bochs_connector_mode_valid,
@@ -230,7 +224,6 @@ static const struct drm_connector_helper_funcs bochs_connector_connector_helper_
 
 static const struct drm_connector_funcs bochs_connector_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = bochs_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = drm_connector_cleanup,
 };

drivers/gpu/drm/bridge/analogix/analogix_dp_core.c

@@ -112,7 +112,7 @@ int analogix_dp_enable_psr(struct device *dev)
 	struct edp_vsc_psr psr_vsc;
 
 	if (!dp->psr_support)
-		return -EINVAL;
+		return 0;
 
 	/* Prepare VSC packet as per EDP 1.4 spec, Table 6.9 */
 	memset(&psr_vsc, 0, sizeof(psr_vsc));
@@ -135,7 +135,7 @@ int analogix_dp_disable_psr(struct device *dev)
 	struct edp_vsc_psr psr_vsc;
 
 	if (!dp->psr_support)
-		return -EINVAL;
+		return 0;
 
 	/* Prepare VSC packet as per EDP 1.4 spec, Table 6.9 */
 	memset(&psr_vsc, 0, sizeof(psr_vsc));

drivers/gpu/drm/bridge/nxp-ptn3460.c

@@ -239,16 +239,9 @@ static const struct drm_connector_helper_funcs ptn3460_connector_helper_funcs =
 	.get_modes = ptn3460_get_modes,
 };
 
-static enum drm_connector_status ptn3460_detect(struct drm_connector *connector,
-		bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_funcs ptn3460_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = ptn3460_detect,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/bridge/parade-ps8622.c

@@ -477,16 +477,9 @@ static const struct drm_connector_helper_funcs ps8622_connector_helper_funcs = {
 	.get_modes = ps8622_get_modes,
 };
 
-static enum drm_connector_status ps8622_detect(struct drm_connector *connector,
-								bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_funcs ps8622_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = ps8622_detect,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/bridge/tc358767.c

@@ -908,7 +908,7 @@ static int tc_main_link_setup(struct tc_data *tc)
 			goto err_dpcd_read;
 
 		if (tmp[0] != tc->assr) {
-			dev_warn(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
+			dev_dbg(dev, "Failed to switch display ASSR to %d, falling back to unscrambled mode\n",
 				 tc->assr);
 			/* trying with disabled scrambler */
 			tc->link.scrambler_dis = 1;
@@ -1038,12 +1038,6 @@ static int tc_main_link_stream(struct tc_data *tc, int state)
 	return ret;
 }
 
-static enum drm_connector_status
-tc_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void tc_bridge_pre_enable(struct drm_bridge *bridge)
 {
 	struct tc_data *tc = bridge_to_tc(bridge);
@@ -1168,7 +1162,6 @@ static const struct drm_connector_helper_funcs tc_connector_helper_funcs = {
 static const struct drm_connector_funcs tc_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = tc_connector_detect,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/cirrus/cirrus_mode.c

@@ -498,12 +498,6 @@ static struct drm_encoder *cirrus_connector_best_encoder(struct drm_connector
 	return NULL;
 }
 
-static enum drm_connector_status cirrus_vga_detect(struct drm_connector
-						   *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void cirrus_connector_destroy(struct drm_connector *connector)
 {
 	drm_connector_cleanup(connector);
@@ -517,7 +511,6 @@ static const struct drm_connector_helper_funcs cirrus_vga_connector_helper_funcs
 
 static const struct drm_connector_funcs cirrus_vga_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = cirrus_vga_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = cirrus_connector_destroy,
 };

drivers/gpu/drm/drm_atomic.c

@@ -1864,20 +1864,6 @@ EXPORT_SYMBOL(drm_atomic_clean_old_fb);
  *	helpers and for the DRM event handling for existing userspace.
  */
 
-static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
-{
-	struct dma_fence *fence;
-
-	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
-	if (!fence)
-		return NULL;
-
-	dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
-		       crtc->fence_context, ++crtc->fence_seqno);
-
-	return fence;
-}
-
 struct drm_out_fence_state {
 	s64 __user *out_fence_ptr;
 	struct sync_file *sync_file;
@@ -1959,7 +1945,7 @@ static int prepare_crtc_signaling(struct drm_device *dev,
 			f[*num_fences].out_fence_ptr = fence_ptr;
 			*fence_state = f;
 
-			fence = get_crtc_fence(crtc);
+			fence = drm_crtc_create_fence(crtc);
 			if (!fence)
 				return -ENOMEM;
 

drivers/gpu/drm/drm_atomic_helper.c

@@ -1234,9 +1234,6 @@ static void commit_work(struct work_struct *work)
  * function implements nonblocking commits, using
  * drm_atomic_helper_setup_commit() and related functions.
  *
- * Note that right now this function does not support nonblocking commits, hence
- * driver writers must implement their own version for now.
- *
  * Committing the actual hardware state is done through the
  * ->atomic_commit_tail() callback of the &drm_mode_config_helper_funcs vtable,
  * or it's default implementation drm_atomic_helper_commit_tail().
@@ -2885,8 +2882,8 @@ int drm_atomic_helper_connector_dpms(struct drm_connector *connector,
 fail:
 	if (ret == -EDEADLK)
 		goto backoff;
-
-	connector->dpms = old_mode;
+	if (ret != 0)
+		connector->dpms = old_mode;
 	drm_atomic_state_put(state);
 	return ret;
 

drivers/gpu/drm/drm_crtc.c

@@ -152,6 +152,8 @@ static void drm_crtc_crc_fini(struct drm_crtc *crtc)
 #endif
 }
 
+static const struct dma_fence_ops drm_crtc_fence_ops;
+
 static struct drm_crtc *fence_to_crtc(struct dma_fence *fence)
 {
 	BUG_ON(fence->ops != &drm_crtc_fence_ops);
@@ -177,13 +179,27 @@ static bool drm_crtc_fence_enable_signaling(struct dma_fence *fence)
 	return true;
 }
 
-const struct dma_fence_ops drm_crtc_fence_ops = {
+static const struct dma_fence_ops drm_crtc_fence_ops = {
 	.get_driver_name = drm_crtc_fence_get_driver_name,
 	.get_timeline_name = drm_crtc_fence_get_timeline_name,
 	.enable_signaling = drm_crtc_fence_enable_signaling,
 	.wait = dma_fence_default_wait,
 };
 
+struct dma_fence *drm_crtc_create_fence(struct drm_crtc *crtc)
+{
+	struct dma_fence *fence;
+
+	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
+	if (!fence)
+		return NULL;
+
+	dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
+		       crtc->fence_context, ++crtc->fence_seqno);
+
+	return fence;
+}
+
 /**
  * drm_crtc_init_with_planes - Initialise a new CRTC object with
  *    specified primary and cursor planes.

drivers/gpu/drm/drm_crtc_internal.h

@@ -43,7 +43,7 @@ int drm_crtc_check_viewport(const struct drm_crtc *crtc,
 int drm_crtc_register_all(struct drm_device *dev);
 void drm_crtc_unregister_all(struct drm_device *dev);
 
-extern const struct dma_fence_ops drm_crtc_fence_ops;
+struct dma_fence *drm_crtc_create_fence(struct drm_crtc *crtc);
 
 /* IOCTLs */
 int drm_mode_getcrtc(struct drm_device *dev,

drivers/gpu/drm/drm_encoder.c

@@ -110,11 +110,9 @@ int drm_encoder_init(struct drm_device *dev,
 {
 	int ret;
 
-	drm_modeset_lock_all(dev);
-
 	ret = drm_mode_object_get(dev, &encoder->base, DRM_MODE_OBJECT_ENCODER);
 	if (ret)
-		goto out_unlock;
+		return ret;
 
 	encoder->dev = dev;
 	encoder->encoder_type = encoder_type;
@@ -142,9 +140,6 @@ int drm_encoder_init(struct drm_device *dev,
 	if (ret)
 		drm_mode_object_unregister(dev, &encoder->base);
 
-out_unlock:
-	drm_modeset_unlock_all(dev);
-
 	return ret;
 }
 EXPORT_SYMBOL(drm_encoder_init);
@@ -164,12 +159,10 @@ void drm_encoder_cleanup(struct drm_encoder *encoder)
 	 * the indices on the drm_encoder after us in the encoder_list.
 	 */
 
-	drm_modeset_lock_all(dev);
 	drm_mode_object_unregister(dev, &encoder->base);
 	kfree(encoder->name);
 	list_del(&encoder->head);
 	dev->mode_config.num_encoder--;
-	drm_modeset_unlock_all(dev);
 
 	memset(encoder, 0, sizeof(*encoder));
 }

drivers/gpu/drm/drm_fb_helper.c

@@ -49,6 +49,7 @@ MODULE_PARM_DESC(fbdev_emulation,
 		 "Enable legacy fbdev emulation [default=true]");
 
 static LIST_HEAD(kernel_fb_helper_list);
+static DEFINE_MUTEX(kernel_fb_helper_lock);
 
 /**
  * DOC: fbdev helpers
@@ -97,6 +98,10 @@ static LIST_HEAD(kernel_fb_helper_list);
  * mmap page writes.
  */
 
+#define drm_fb_helper_for_each_connector(fbh, i__) \
+	for (({ lockdep_assert_held(&(fbh)->dev->mode_config.mutex); }), \
+	     i__ = 0; i__ < (fbh)->connector_count; i__++)
+
 /**
  * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
  * 					       emulation helper
@@ -130,7 +135,7 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
 	mutex_unlock(&dev->mode_config.mutex);
 	return 0;
 fail:
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		struct drm_fb_helper_connector *fb_helper_connector =
 			fb_helper->connector_info[i];
 
@@ -565,7 +570,7 @@ static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 			continue;
 
 		/* Walk the connectors & encoders on this fb turning them on/off */
-		for (j = 0; j < fb_helper->connector_count; j++) {
+		drm_fb_helper_for_each_connector(fb_helper, j) {
 			connector = fb_helper->connector_info[j]->connector;
 			connector->funcs->dpms(connector, dpms_mode);
 			drm_object_property_set_value(&connector->base,
@@ -851,12 +856,14 @@ void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 	if (!drm_fbdev_emulation)
 		return;
 
+	mutex_lock(&kernel_fb_helper_lock);
 	if (!list_empty(&fb_helper->kernel_fb_list)) {
 		list_del(&fb_helper->kernel_fb_list);
 		if (list_empty(&kernel_fb_helper_list)) {
 			unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 		}
 	}
+	mutex_unlock(&kernel_fb_helper_lock);
 
 	drm_fb_helper_crtc_free(fb_helper);
 
@@ -1469,7 +1476,6 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 	int ret = 0;
 	int crtc_count = 0;
 	int i;
-	struct fb_info *info;
 	struct drm_fb_helper_surface_size sizes;
 	int gamma_size = 0;
 
@@ -1485,7 +1491,7 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 		sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
 
 	/* first up get a count of crtcs now in use and new min/maxes width/heights */
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
 		struct drm_cmdline_mode *cmdline_mode;
 
@@ -1572,8 +1578,6 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 	if (ret < 0)
 		return ret;
 
-	info = fb_helper->fbdev;
-
 	/*
 	 * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
 	 * events, but at init time drm_setup_crtcs needs to be called before
@@ -1585,20 +1589,6 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 		if (fb_helper->crtc_info[i].mode_set.num_connectors)
 			fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
 
-
-	info->var.pixclock = 0;
-	if (register_framebuffer(info) < 0)
-		return -EINVAL;
-
-	dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
-			info->node, info->fix.id);
-
-	if (list_empty(&kernel_fb_helper_list)) {
-		register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
-	}
-
-	list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
-
 	return 0;
 }
 
@@ -1730,7 +1720,7 @@ static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
 	int count = 0;
 	int i;
 
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		connector = fb_helper->connector_info[i]->connector;
 		count += connector->funcs->fill_modes(connector, maxX, maxY);
 	}
@@ -1830,7 +1820,7 @@ static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
 	struct drm_connector *connector;
 	int i = 0;
 
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		connector = fb_helper->connector_info[i]->connector;
 		enabled[i] = drm_connector_enabled(connector, true);
 		DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
@@ -1841,7 +1831,7 @@ static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
 	if (any_enabled)
 		return;
 
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		connector = fb_helper->connector_info[i]->connector;
 		enabled[i] = drm_connector_enabled(connector, false);
 	}
@@ -1862,7 +1852,7 @@ static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
 		return false;
 
 	count = 0;
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		if (enabled[i])
 			count++;
 	}
@@ -1873,7 +1863,7 @@ static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
 
 	/* check the command line or if nothing common pick 1024x768 */
 	can_clone = true;
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		if (!enabled[i])
 			continue;
 		fb_helper_conn = fb_helper->connector_info[i];
@@ -1899,8 +1889,7 @@ static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
 	can_clone = true;
 	dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
 
-	for (i = 0; i < fb_helper->connector_count; i++) {
-
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		if (!enabled[i])
 			continue;
 
@@ -1931,7 +1920,7 @@ static int drm_get_tile_offsets(struct drm_fb_helper *fb_helper,
 	int i;
 	int hoffset = 0, voffset = 0;
 
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		fb_helper_conn = fb_helper->connector_info[i];
 		if (!fb_helper_conn->connector->has_tile)
 			continue;
@@ -1965,7 +1954,7 @@ static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
 	int i;
 
 retry:
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		fb_helper_conn = fb_helper->connector_info[i];
 
 		if (conn_configured & BIT_ULL(i))
@@ -2113,20 +2102,22 @@ static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
 	return best_score;
 }
 
-static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
+static void drm_setup_crtcs(struct drm_fb_helper *fb_helper,
+			    u32 width, u32 height)
 {
 	struct drm_device *dev = fb_helper->dev;
 	struct drm_fb_helper_crtc **crtcs;
 	struct drm_display_mode **modes;
 	struct drm_fb_offset *offsets;
 	bool *enabled;
-	int width, height;
 	int i;
 
 	DRM_DEBUG_KMS("\n");
+	if (drm_fb_helper_probe_connector_modes(fb_helper, width, height) == 0)
+		DRM_DEBUG_KMS("No connectors reported connected with modes\n");
 
-	width = dev->mode_config.max_width;
-	height = dev->mode_config.max_height;
+	/* prevent concurrent modification of connector_count by hotplug */
+	lockdep_assert_held(&fb_helper->dev->mode_config.mutex);
 
 	crtcs = kcalloc(fb_helper->connector_count,
 			sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
@@ -2141,7 +2132,6 @@ static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
 		goto out;
 	}
 
-
 	drm_enable_connectors(fb_helper, enabled);
 
 	if (!(fb_helper->funcs->initial_config &&
@@ -2170,7 +2160,7 @@ static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
 		drm_fb_helper_modeset_release(fb_helper,
 					      &fb_helper->crtc_info[i].mode_set);
 
-	for (i = 0; i < fb_helper->connector_count; i++) {
+	drm_fb_helper_for_each_connector(fb_helper, i) {
 		struct drm_display_mode *mode = modes[i];
 		struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
 		struct drm_fb_offset *offset = &offsets[i];
@@ -2247,25 +2237,38 @@ static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
 {
 	struct drm_device *dev = fb_helper->dev;
-	int count = 0;
+	struct fb_info *info;
+	int ret;
 
 	if (!drm_fbdev_emulation)
 		return 0;
 
 	mutex_lock(&dev->mode_config.mutex);
-	count = drm_fb_helper_probe_connector_modes(fb_helper,
-						    dev->mode_config.max_width,
-						    dev->mode_config.max_height);
+	drm_setup_crtcs(fb_helper,
+			dev->mode_config.max_width,
+			dev->mode_config.max_height);
+	ret = drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
 	mutex_unlock(&dev->mode_config.mutex);
-	/*
-	 * we shouldn't end up with no modes here.
-	 */
-	if (count == 0)
-		dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
+	if (ret)
+		return ret;
+
+	info = fb_helper->fbdev;
+	info->var.pixclock = 0;
+	ret = register_framebuffer(info);
+	if (ret < 0)
+		return ret;
+
+	dev_info(dev->dev, "fb%d: %s frame buffer device\n",
+		 info->node, info->fix.id);
+
+	mutex_lock(&kernel_fb_helper_lock);
+	if (list_empty(&kernel_fb_helper_list))
+		register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 
-	drm_setup_crtcs(fb_helper);
+	list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
+	mutex_unlock(&kernel_fb_helper_lock);
 
-	return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
+	return 0;
 }
 EXPORT_SYMBOL(drm_fb_helper_initial_config);
 
@@ -2293,28 +2296,22 @@ EXPORT_SYMBOL(drm_fb_helper_initial_config);
 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 {
 	struct drm_device *dev = fb_helper->dev;
-	u32 max_width, max_height;
 
 	if (!drm_fbdev_emulation)
 		return 0;
 
-	mutex_lock(&fb_helper->dev->mode_config.mutex);
+	mutex_lock(&dev->mode_config.mutex);
 	if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
 		fb_helper->delayed_hotplug = true;
-		mutex_unlock(&fb_helper->dev->mode_config.mutex);
+		mutex_unlock(&dev->mode_config.mutex);
 		return 0;
 	}
 	DRM_DEBUG_KMS("\n");
 
-	max_width = fb_helper->fb->width;
-	max_height = fb_helper->fb->height;
+	drm_setup_crtcs(fb_helper, fb_helper->fb->width, fb_helper->fb->height);
 
-	drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
-	mutex_unlock(&fb_helper->dev->mode_config.mutex);
+	mutex_unlock(&dev->mode_config.mutex);
 
-	drm_modeset_lock_all(dev);
-	drm_setup_crtcs(fb_helper);
-	drm_modeset_unlock_all(dev);
 	drm_fb_helper_set_par(fb_helper->fbdev);
 
 	return 0;

drivers/gpu/drm/drm_ioctl.c

@@ -229,6 +229,22 @@ static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_
 	struct drm_crtc *crtc;
 
 	req->value = 0;
+
+	/* Only some caps make sense with UMS/render-only drivers. */
+	switch (req->capability) {
+	case DRM_CAP_TIMESTAMP_MONOTONIC:
+		req->value = drm_timestamp_monotonic;
+		return 0;
+	case DRM_CAP_PRIME:
+		req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
+		req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
+		return 0;
+	}
+
+	/* Other caps only work with KMS drivers */
+	if (!drm_core_check_feature(dev, DRIVER_MODESET))
+		return -ENOTSUPP;
+
 	switch (req->capability) {
 	case DRM_CAP_DUMB_BUFFER:
 		if (dev->driver->dumb_create)
@@ -243,23 +259,14 @@ static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_
 	case DRM_CAP_DUMB_PREFER_SHADOW:
 		req->value = dev->mode_config.prefer_shadow;
 		break;
-	case DRM_CAP_PRIME:
-		req->value |= dev->driver->prime_fd_to_handle ? DRM_PRIME_CAP_IMPORT : 0;
-		req->value |= dev->driver->prime_handle_to_fd ? DRM_PRIME_CAP_EXPORT : 0;
-		break;
-	case DRM_CAP_TIMESTAMP_MONOTONIC:
-		req->value = drm_timestamp_monotonic;
-		break;
 	case DRM_CAP_ASYNC_PAGE_FLIP:
 		req->value = dev->mode_config.async_page_flip;
 		break;
 	case DRM_CAP_PAGE_FLIP_TARGET:
-		if (drm_core_check_feature(dev, DRIVER_MODESET)) {
-			req->value = 1;
-			drm_for_each_crtc(crtc, dev) {
-				if (!crtc->funcs->page_flip_target)
-					req->value = 0;
-			}
+		req->value = 1;
+		drm_for_each_crtc(crtc, dev) {
+			if (!crtc->funcs->page_flip_target)
+				req->value = 0;
 		}
 		break;
 	case DRM_CAP_CURSOR_WIDTH:

drivers/gpu/drm/drm_mm.c

@@ -905,6 +905,7 @@ void drm_mm_init(struct drm_mm * mm, u64 start, u64 size)
 
 	/* Clever trick to avoid a special case in the free hole tracking. */
 	INIT_LIST_HEAD(&mm->head_node.node_list);
+	mm->head_node.allocated = 0;
 	mm->head_node.hole_follows = 1;
 	mm->head_node.scanned_block = 0;
 	mm->head_node.scanned_prev_free = 0;

drivers/gpu/drm/drm_modeset_lock.c

@@ -52,12 +52,12 @@
  *     drm_modeset_drop_locks(&ctx);
  *     drm_modeset_acquire_fini(&ctx);
  *
- *  On top of of these per-object locks using &ww_mutex there's also an overall
- *  dev->mode_config.lock, for protecting everything else. Mostly this means
- *  probe state of connectors, and preventing hotplug add/removal of connectors.
+ * On top of of these per-object locks using &ww_mutex there's also an overall
+ * dev->mode_config.lock, for protecting everything else. Mostly this means
+ * probe state of connectors, and preventing hotplug add/removal of connectors.
  *
- *  Finally there's a bunch of dedicated locks to protect drm core internal
- *  lists and lookup data structures.
+ * Finally there's a bunch of dedicated locks to protect drm core internal
+ * lists and lookup data structures.
  */
 
 static DEFINE_WW_CLASS(crtc_ww_class);

drivers/gpu/drm/drm_plane.c

@@ -221,7 +221,8 @@ void drm_plane_cleanup(struct drm_plane *plane)
 {
 	struct drm_device *dev = plane->dev;
 
-	drm_modeset_lock_all(dev);
+	drm_modeset_lock_fini(&plane->mutex);
+
 	kfree(plane->format_types);
 	drm_mode_object_unregister(dev, &plane->base);
 
@@ -236,7 +237,6 @@ void drm_plane_cleanup(struct drm_plane *plane)
 	dev->mode_config.num_total_plane--;
 	if (plane->type == DRM_PLANE_TYPE_OVERLAY)
 		dev->mode_config.num_overlay_plane--;
-	drm_modeset_unlock_all(dev);
 
 	WARN_ON(plane->state && !plane->funcs->atomic_destroy_state);
 	if (plane->state && plane->funcs->atomic_destroy_state)

drivers/gpu/drm/drm_prime.c

@@ -290,7 +290,8 @@ static void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
  *
  * This wraps dma_buf_export() for use by generic GEM drivers that are using
  * drm_gem_dmabuf_release(). In addition to calling dma_buf_export(), we take
- * a reference to the drm_device which is released by drm_gem_dmabuf_release().
+ * a reference to the &drm_device and the exported &drm_gem_object (stored in
+ * exp_info->priv) which is released by drm_gem_dmabuf_release().
  *
  * Returns the new dmabuf.
  */
@@ -300,8 +301,11 @@ struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev,
 	struct dma_buf *dma_buf;
 
 	dma_buf = dma_buf_export(exp_info);
-	if (!IS_ERR(dma_buf))
-		drm_dev_ref(dev);
+	if (IS_ERR(dma_buf))
+		return dma_buf;
+
+	drm_dev_ref(dev);
+	drm_gem_object_reference(exp_info->priv);
 
 	return dma_buf;
 }
@@ -472,8 +476,6 @@ static struct dma_buf *export_and_register_object(struct drm_device *dev,
 	 */
 	obj->dma_buf = dmabuf;
 	get_dma_buf(obj->dma_buf);
-	/* Grab a new ref since the callers is now used by the dma-buf */
-	drm_gem_object_reference(obj);
 
 	return dmabuf;
 }

drivers/gpu/drm/drm_probe_helper.c

@@ -152,6 +152,14 @@ void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
 }
 EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked);
 
+static enum drm_connector_status
+drm_connector_detect(struct drm_connector *connector, bool force)
+{
+	return connector->funcs->detect ?
+		connector->funcs->detect(connector, force) :
+		connector_status_connected;
+}
+
 /**
  * drm_helper_probe_single_connector_modes - get complete set of display modes
  * @connector: connector to probe
@@ -239,7 +247,7 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
 		if (connector->funcs->force)
 			connector->funcs->force(connector);
 	} else {
-		connector->status = connector->funcs->detect(connector, true);
+		connector->status = drm_connector_detect(connector, true);
 	}
 
 	/*
@@ -384,7 +392,11 @@ static void output_poll_execute(struct work_struct *work)
 	if (!drm_kms_helper_poll)
 		goto out;
 
-	mutex_lock(&dev->mode_config.mutex);
+	if (!mutex_trylock(&dev->mode_config.mutex)) {
+		repoll = true;
+		goto out;
+	}
+
 	drm_for_each_connector(connector, dev) {
 
 		/* Ignore forced connectors. */
@@ -405,7 +417,7 @@ static void output_poll_execute(struct work_struct *work)
 
 		repoll = true;
 
-		connector->status = connector->funcs->detect(connector, false);
+		connector->status = drm_connector_detect(connector, false);
 		if (old_status != connector->status) {
 			const char *old, *new;
 
@@ -565,7 +577,7 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev)
 
 		old_status = connector->status;
 
-		connector->status = connector->funcs->detect(connector, false);
+		connector->status = drm_connector_detect(connector, false);
 		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
 			      connector->base.id,
 			      connector->name,

drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c

@@ -58,17 +58,10 @@ static void fsl_dcu_drm_connector_destroy(struct drm_connector *connector)
 	drm_connector_cleanup(connector);
 }
 
-static enum drm_connector_status
-fsl_dcu_drm_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_funcs fsl_dcu_drm_connector_funcs = {
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.destroy = fsl_dcu_drm_connector_destroy,
-	.detect = fsl_dcu_drm_connector_detect,
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.reset = drm_atomic_helper_connector_reset,

drivers/gpu/drm/gma500/cdv_intel_lvds.c

@@ -386,19 +386,6 @@ static void cdv_intel_lvds_mode_set(struct drm_encoder *encoder,
 	REG_WRITE(PFIT_CONTROL, pfit_control);
 }
 
-/**
- * Detect the LVDS connection.
- *
- * This always returns CONNECTOR_STATUS_CONNECTED.
- * This connector should only have
- * been set up if the LVDS was actually connected anyway.
- */
-static enum drm_connector_status cdv_intel_lvds_detect(
-				struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 /**
  * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
  */
@@ -521,7 +508,6 @@ static const struct drm_connector_helper_funcs
 
 static const struct drm_connector_funcs cdv_intel_lvds_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = cdv_intel_lvds_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.set_property = cdv_intel_lvds_set_property,
 	.destroy = cdv_intel_lvds_destroy,

drivers/gpu/drm/gma500/psb_intel_lvds.c

@@ -499,19 +499,6 @@ static void psb_intel_lvds_mode_set(struct drm_encoder *encoder,
 	REG_WRITE(PFIT_CONTROL, pfit_control);
 }
 
-/*
- * Detect the LVDS connection.
- *
- * This always returns CONNECTOR_STATUS_CONNECTED.
- * This connector should only have
- * been set up if the LVDS was actually connected anyway.
- */
-static enum drm_connector_status psb_intel_lvds_detect(struct drm_connector
-						   *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 /*
  * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
  */
@@ -643,7 +630,6 @@ const struct drm_connector_helper_funcs
 
 const struct drm_connector_funcs psb_intel_lvds_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = psb_intel_lvds_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.set_property = psb_intel_lvds_set_property,
 	.destroy = psb_intel_lvds_destroy,

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_vdac.c

@@ -39,12 +39,6 @@ hibmc_connector_best_encoder(struct drm_connector *connector)
 	return drm_encoder_find(connector->dev, connector->encoder_ids[0]);
 }
 
-static enum drm_connector_status hibmc_connector_detect(struct drm_connector
-						 *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_helper_funcs
 	hibmc_connector_helper_funcs = {
 	.get_modes = hibmc_connector_get_modes,
@@ -54,7 +48,6 @@ static const struct drm_connector_helper_funcs
 
 static const struct drm_connector_funcs hibmc_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
-	.detect = hibmc_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,

drivers/gpu/drm/i915/intel_dsi.c

@@ -1298,12 +1298,6 @@ static void intel_dsi_prepare(struct intel_encoder *intel_encoder,
 	}
 }
 
-static enum drm_connector_status
-intel_dsi_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static int intel_dsi_get_modes(struct drm_connector *connector)
 {
 	struct intel_connector *intel_connector = to_intel_connector(connector);
@@ -1407,7 +1401,6 @@ static const struct drm_connector_helper_funcs intel_dsi_connector_helper_funcs
 
 static const struct drm_connector_funcs intel_dsi_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
-	.detect = intel_dsi_detect,
 	.late_register = intel_connector_register,
 	.early_unregister = intel_connector_unregister,
 	.destroy = intel_dsi_connector_destroy,

drivers/gpu/drm/imx/imx-ldb.c

@@ -101,12 +101,6 @@ struct imx_ldb {
 	const struct bus_mux *lvds_mux;
 };
 
-static enum drm_connector_status imx_ldb_connector_detect(
-		struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void imx_ldb_ch_set_bus_format(struct imx_ldb_channel *imx_ldb_ch,
 				      u32 bus_format)
 {
@@ -397,7 +391,6 @@ static int imx_ldb_encoder_atomic_check(struct drm_encoder *encoder,
 static const struct drm_connector_funcs imx_ldb_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = imx_ldb_connector_detect,
 	.destroy = imx_drm_connector_destroy,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/imx/imx-tve.c

@@ -227,12 +227,6 @@ static int tve_setup_vga(struct imx_tve *tve)
 				 TVE_TVDAC_TEST_MODE_MASK, 1);
 }
 
-static enum drm_connector_status imx_tve_connector_detect(
-				struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static int imx_tve_connector_get_modes(struct drm_connector *connector)
 {
 	struct imx_tve *tve = con_to_tve(connector);
@@ -352,7 +346,6 @@ static int imx_tve_atomic_check(struct drm_encoder *encoder,
 static const struct drm_connector_funcs imx_tve_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = imx_tve_connector_detect,
 	.destroy = imx_drm_connector_destroy,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/imx/parallel-display.c

@@ -49,12 +49,6 @@ static inline struct imx_parallel_display *enc_to_imxpd(struct drm_encoder *e)
 	return container_of(e, struct imx_parallel_display, encoder);
 }
 
-static enum drm_connector_status imx_pd_connector_detect(
-		struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static int imx_pd_connector_get_modes(struct drm_connector *connector)
 {
 	struct imx_parallel_display *imxpd = con_to_imxpd(connector);
@@ -143,7 +137,6 @@ static int imx_pd_encoder_atomic_check(struct drm_encoder *encoder,
 static const struct drm_connector_funcs imx_pd_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = imx_pd_connector_detect,
 	.destroy = imx_drm_connector_destroy,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/mediatek/mtk_dsi.c

@@ -594,12 +594,6 @@ static void mtk_dsi_encoder_enable(struct drm_encoder *encoder)
 	mtk_output_dsi_enable(dsi);
 }
 
-static enum drm_connector_status mtk_dsi_connector_detect(
-	struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static int mtk_dsi_connector_get_modes(struct drm_connector *connector)
 {
 	struct mtk_dsi *dsi = connector_to_dsi(connector);
@@ -616,7 +610,6 @@ static const struct drm_encoder_helper_funcs mtk_dsi_encoder_helper_funcs = {
 
 static const struct drm_connector_funcs mtk_dsi_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
-	.detect = mtk_dsi_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,

drivers/gpu/drm/mgag200/mgag200_mode.c

@@ -1658,12 +1658,6 @@ static struct drm_encoder *mga_connector_best_encoder(struct drm_connector
 	return NULL;
 }
 
-static enum drm_connector_status mga_vga_detect(struct drm_connector
-						   *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void mga_connector_destroy(struct drm_connector *connector)
 {
 	struct mga_connector *mga_connector = to_mga_connector(connector);
@@ -1680,7 +1674,6 @@ static const struct drm_connector_helper_funcs mga_vga_connector_helper_funcs =
 
 static const struct drm_connector_funcs mga_vga_connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = mga_vga_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = mga_connector_destroy,
 };

drivers/gpu/drm/qxl/qxl_debugfs.c

@@ -122,9 +122,6 @@ int qxl_debugfs_add_files(struct qxl_device *qdev,
 	qdev->debugfs[qdev->debugfs_count].num_files = nfiles;
 	qdev->debugfs_count = i;
 #if defined(CONFIG_DEBUG_FS)
-	drm_debugfs_create_files(files, nfiles,
-				 qdev->ddev->control->debugfs_root,
-				 qdev->ddev->control);
 	drm_debugfs_create_files(files, nfiles,
 				 qdev->ddev->primary->debugfs_root,
 				 qdev->ddev->primary);
@@ -138,9 +135,6 @@ void qxl_debugfs_remove_files(struct qxl_device *qdev)
 	unsigned i;
 
 	for (i = 0; i < qdev->debugfs_count; i++) {
-		drm_debugfs_remove_files(qdev->debugfs[i].files,
-					 qdev->debugfs[i].num_files,
-					 qdev->ddev->control);
 		drm_debugfs_remove_files(qdev->debugfs[i].files,
 					 qdev->debugfs[i].num_files,
 					 qdev->ddev->primary);

drivers/gpu/drm/qxl/qxl_release.c

@@ -134,7 +134,7 @@ qxl_release_alloc(struct qxl_device *qdev, int type,
 	release = kmalloc(size, GFP_KERNEL);
 	if (!release) {
 		DRM_ERROR("Out of memory\n");
-		return 0;
+		return -ENOMEM;
 	}
 	release->base.ops = NULL;
 	release->type = type;

drivers/gpu/drm/radeon/radeon_device.c

@@ -1948,9 +1948,6 @@ int radeon_debugfs_add_files(struct radeon_device *rdev,
 	rdev->debugfs[rdev->debugfs_count].num_files = nfiles;
 	rdev->debugfs_count = i;
 #if defined(CONFIG_DEBUG_FS)
-	drm_debugfs_create_files(files, nfiles,
-				 rdev->ddev->control->debugfs_root,
-				 rdev->ddev->control);
 	drm_debugfs_create_files(files, nfiles,
 				 rdev->ddev->primary->debugfs_root,
 				 rdev->ddev->primary);
@@ -1964,9 +1961,6 @@ static void radeon_debugfs_remove_files(struct radeon_device *rdev)
 	unsigned i;
 
 	for (i = 0; i < rdev->debugfs_count; i++) {
-		drm_debugfs_remove_files(rdev->debugfs[i].files,
-					 rdev->debugfs[i].num_files,
-					 rdev->ddev->control);
 		drm_debugfs_remove_files(rdev->debugfs[i].files,
 					 rdev->debugfs[i].num_files,
 					 rdev->ddev->primary);

drivers/gpu/drm/rcar-du/rcar_du_lvdscon.c

@@ -61,16 +61,9 @@ static const struct drm_connector_helper_funcs connector_helper_funcs = {
 	.get_modes = rcar_du_lvds_connector_get_modes,
 };
 
-static enum drm_connector_status
-rcar_du_lvds_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_funcs connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.reset = drm_atomic_helper_connector_reset,
-	.detect = rcar_du_lvds_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = drm_connector_cleanup,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/rockchip/dw-mipi-dsi.c

@@ -969,12 +969,6 @@ static struct drm_connector_helper_funcs dw_mipi_dsi_connector_helper_funcs = {
 	.mode_valid = dw_mipi_dsi_mode_valid,
 };
 
-static enum drm_connector_status
-dw_mipi_dsi_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void dw_mipi_dsi_drm_connector_destroy(struct drm_connector *connector)
 {
 	drm_connector_unregister(connector);
@@ -984,7 +978,6 @@ static void dw_mipi_dsi_drm_connector_destroy(struct drm_connector *connector)
 static struct drm_connector_funcs dw_mipi_dsi_atomic_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = dw_mipi_dsi_detect,
 	.destroy = dw_mipi_dsi_drm_connector_destroy,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/shmobile/shmob_drm_crtc.c

@@ -669,15 +669,8 @@ static void shmob_drm_connector_destroy(struct drm_connector *connector)
 	drm_connector_cleanup(connector);
 }
 
-static enum drm_connector_status
-shmob_drm_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static const struct drm_connector_funcs connector_funcs = {
 	.dpms = drm_helper_connector_dpms,
-	.detect = shmob_drm_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = shmob_drm_connector_destroy,
 };

drivers/gpu/drm/sti/sti_hda.c

@@ -642,12 +642,6 @@ struct drm_connector_helper_funcs sti_hda_connector_helper_funcs = {
 	.mode_valid = sti_hda_connector_mode_valid,
 };
 
-static enum drm_connector_status
-sti_hda_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static int sti_hda_late_register(struct drm_connector *connector)
 {
 	struct sti_hda_connector *hda_connector
@@ -665,7 +659,6 @@ static int sti_hda_late_register(struct drm_connector *connector)
 static const struct drm_connector_funcs sti_hda_connector_funcs = {
 	.dpms = drm_atomic_helper_connector_dpms,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.detect = sti_hda_connector_detect,
 	.destroy = drm_connector_cleanup,
 	.reset = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/sun4i/sun4i_rgb.c

@@ -110,12 +110,6 @@ static struct drm_connector_helper_funcs sun4i_rgb_con_helper_funcs = {
 	.mode_valid	= sun4i_rgb_mode_valid,
 };
 
-static enum drm_connector_status
-sun4i_rgb_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void
 sun4i_rgb_connector_destroy(struct drm_connector *connector)
 {
@@ -129,7 +123,6 @@ sun4i_rgb_connector_destroy(struct drm_connector *connector)
 
 static struct drm_connector_funcs sun4i_rgb_con_funcs = {
 	.dpms			= drm_atomic_helper_connector_dpms,
-	.detect			= sun4i_rgb_connector_detect,
 	.fill_modes		= drm_helper_probe_single_connector_modes,
 	.destroy		= sun4i_rgb_connector_destroy,
 	.reset			= drm_atomic_helper_connector_reset,

drivers/gpu/drm/sun4i/sun4i_tv.c

@@ -537,12 +537,6 @@ static struct drm_connector_helper_funcs sun4i_tv_comp_connector_helper_funcs =
 	.mode_valid	= sun4i_tv_comp_mode_valid,
 };
 
-static enum drm_connector_status
-sun4i_tv_comp_connector_detect(struct drm_connector *connector, bool force)
-{
-	return connector_status_connected;
-}
-
 static void
 sun4i_tv_comp_connector_destroy(struct drm_connector *connector)
 {
@@ -551,7 +545,6 @@ sun4i_tv_comp_connector_destroy(struct drm_connector *connector)
 
 static struct drm_connector_funcs sun4i_tv_comp_connector_funcs = {
 	.dpms			= drm_atomic_helper_connector_dpms,
-	.detect			= sun4i_tv_comp_connector_detect,
 	.fill_modes		= drm_helper_probe_single_connector_modes,
 	.destroy		= sun4i_tv_comp_connector_destroy,
 	.reset			= drm_atomic_helper_connector_reset,

drivers/gpu/drm/tilcdc/tilcdc_panel.c

@@ -144,13 +144,6 @@ static void panel_connector_destroy(struct drm_connector *connector)
 	drm_connector_cleanup(connector);
 }
 
-static enum drm_connector_status panel_connector_detect(
-		struct drm_connector *connector,
-		bool force)
-{
-	return connector_status_connected;
-}
-
 static int panel_connector_get_modes(struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
@@ -197,7 +190,6 @@ static struct drm_encoder *panel_connector_best_encoder(
 static const struct drm_connector_funcs panel_connector_funcs = {
 	.destroy            = panel_connector_destroy,
 	.dpms               = drm_atomic_helper_connector_dpms,
-	.detect             = panel_connector_detect,
 	.fill_modes         = drm_helper_probe_single_connector_modes,
 	.reset              = drm_atomic_helper_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,

drivers/gpu/drm/vgem/vgem_fence.c

@@ -126,7 +126,6 @@ static int attach_dmabuf(struct drm_device *dev,
 		return PTR_ERR(dmabuf);
 
 	obj->dma_buf = dmabuf;
-	drm_gem_object_reference(obj);
 	return 0;
 }
 
@@ -191,12 +190,12 @@ int vgem_fence_attach_ioctl(struct drm_device *dev,
 
 	/* Expose the fence via the dma-buf */
 	ret = 0;
-	mutex_lock(&resv->lock.base);
+	ww_mutex_lock(&resv->lock, NULL);
 	if (arg->flags & VGEM_FENCE_WRITE)
 		reservation_object_add_excl_fence(resv, fence);
 	else if ((ret = reservation_object_reserve_shared(resv)) == 0)
 		reservation_object_add_shared_fence(resv, fence);
-	mutex_unlock(&resv->lock.base);
+	ww_mutex_unlock(&resv->lock);
 
 	/* Record the fence in our idr for later signaling */
 	if (ret == 0) {

drivers/gpu/drm/vmwgfx/vmwgfx_fb.c

@@ -465,33 +465,34 @@ static int vmw_fb_kms_detach(struct vmw_fb_par *par,
 
 static int vmw_fb_kms_framebuffer(struct fb_info *info)
 {
-	struct drm_mode_fb_cmd mode_cmd;
+	struct drm_mode_fb_cmd2 mode_cmd;
 	struct vmw_fb_par *par = info->par;
 	struct fb_var_screeninfo *var = &info->var;
 	struct drm_framebuffer *cur_fb;
 	struct vmw_framebuffer *vfb;
-	int ret = 0;
+	int ret = 0, depth;
 	size_t new_bo_size;
 
-	ret = vmw_fb_compute_depth(var, &mode_cmd.depth);
+	ret = vmw_fb_compute_depth(var, &depth);
 	if (ret)
 		return ret;
 
 	mode_cmd.width = var->xres;
 	mode_cmd.height = var->yres;
-	mode_cmd.bpp = var->bits_per_pixel;
-	mode_cmd.pitch = ((mode_cmd.bpp + 7) / 8) * mode_cmd.width;
+	mode_cmd.pitches[0] = ((var->bits_per_pixel + 7) / 8) * mode_cmd.width;
+	mode_cmd.pixel_format =
+		drm_mode_legacy_fb_format(var->bits_per_pixel,
+			((var->bits_per_pixel + 7) / 8) * mode_cmd.width);
 
 	cur_fb = par->set_fb;
 	if (cur_fb && cur_fb->width == mode_cmd.width &&
 	    cur_fb->height == mode_cmd.height &&
-	    cur_fb->bits_per_pixel == mode_cmd.bpp &&
-	    cur_fb->depth == mode_cmd.depth &&
-	    cur_fb->pitches[0] == mode_cmd.pitch)
+	    cur_fb->pixel_format == mode_cmd.pixel_format &&
+	    cur_fb->pitches[0] == mode_cmd.pitches[0])
 		return 0;
 
 	/* Need new buffer object ? */
-	new_bo_size = (size_t) mode_cmd.pitch * (size_t) mode_cmd.height;
+	new_bo_size = (size_t) mode_cmd.pitches[0] * (size_t) mode_cmd.height;
 	ret = vmw_fb_kms_detach(par,
 				par->bo_size < new_bo_size ||
 				par->bo_size > 2*new_bo_size,

drivers/gpu/drm/vmwgfx/vmwgfx_kms.c

@@ -516,7 +516,7 @@ static const struct drm_framebuffer_funcs vmw_framebuffer_surface_funcs = {
 static int vmw_kms_new_framebuffer_surface(struct vmw_private *dev_priv,
 					   struct vmw_surface *surface,
 					   struct vmw_framebuffer **out,
-					   const struct drm_mode_fb_cmd
+					   const struct drm_mode_fb_cmd2
 					   *mode_cmd,
 					   bool is_dmabuf_proxy)
 
@@ -525,6 +525,7 @@ static int vmw_kms_new_framebuffer_surface(struct vmw_private *dev_priv,
 	struct vmw_framebuffer_surface *vfbs;
 	enum SVGA3dSurfaceFormat format;
 	int ret;
+	struct drm_format_name_buf format_name;
 
 	/* 3D is only supported on HWv8 and newer hosts */
 	if (dev_priv->active_display_unit == vmw_du_legacy)
@@ -548,21 +549,22 @@ static int vmw_kms_new_framebuffer_surface(struct vmw_private *dev_priv,
 		return -EINVAL;
 	}
 
-	switch (mode_cmd->depth) {
-	case 32:
+	switch (mode_cmd->pixel_format) {
+	case DRM_FORMAT_ARGB8888:
 		format = SVGA3D_A8R8G8B8;
 		break;
-	case 24:
+	case DRM_FORMAT_XRGB8888:
 		format = SVGA3D_X8R8G8B8;
 		break;
-	case 16:
+	case DRM_FORMAT_RGB565:
 		format = SVGA3D_R5G6B5;
 		break;
-	case 15:
+	case DRM_FORMAT_XRGB1555:
 		format = SVGA3D_A1R5G5B5;
 		break;
 	default:
-		DRM_ERROR("Invalid color depth: %d\n", mode_cmd->depth);
+		DRM_ERROR("Invalid pixel format: %s\n",
+			  drm_get_format_name(mode_cmd->pixel_format, &format_name));
 		return -EINVAL;
 	}
 
@@ -581,14 +583,9 @@ static int vmw_kms_new_framebuffer_surface(struct vmw_private *dev_priv,
 		goto out_err1;
 	}
 
-	/* XXX get the first 3 from the surface info */
-	vfbs->base.base.bits_per_pixel = mode_cmd->bpp;
-	vfbs->base.base.pitches[0] = mode_cmd->pitch;
-	vfbs->base.base.depth = mode_cmd->depth;
-	vfbs->base.base.width = mode_cmd->width;
-	vfbs->base.base.height = mode_cmd->height;
+	drm_helper_mode_fill_fb_struct(&vfbs->base.base, mode_cmd);
 	vfbs->surface = vmw_surface_reference(surface);
-	vfbs->base.user_handle = mode_cmd->handle;
+	vfbs->base.user_handle = mode_cmd->handles[0];
 	vfbs->is_dmabuf_proxy = is_dmabuf_proxy;
 
 	*out = &vfbs->base;
@@ -755,7 +752,7 @@ static int vmw_framebuffer_unpin(struct vmw_framebuffer *vfb)
  * 0 on success, error code otherwise
  */
 static int vmw_create_dmabuf_proxy(struct drm_device *dev,
-				   const struct drm_mode_fb_cmd *mode_cmd,
+				   const struct drm_mode_fb_cmd2 *mode_cmd,
 				   struct vmw_dma_buffer *dmabuf_mob,
 				   struct vmw_surface **srf_out)
 {
@@ -763,17 +760,18 @@ static int vmw_create_dmabuf_proxy(struct drm_device *dev,
 	struct drm_vmw_size content_base_size;
 	struct vmw_resource *res;
 	unsigned int bytes_pp;
+	struct drm_format_name_buf format_name;
 	int ret;
 
-	switch (mode_cmd->depth) {
-	case 32:
-	case 24:
+	switch (mode_cmd->pixel_format) {
+	case DRM_FORMAT_ARGB8888:
+	case DRM_FORMAT_XRGB8888:
 		format = SVGA3D_X8R8G8B8;
 		bytes_pp = 4;
 		break;
 
-	case 16:
-	case 15:
+	case DRM_FORMAT_RGB565:
+	case DRM_FORMAT_XRGB1555:
 		format = SVGA3D_R5G6B5;
 		bytes_pp = 2;
 		break;
@@ -784,11 +782,12 @@ static int vmw_create_dmabuf_proxy(struct drm_device *dev,
 		break;
 
 	default:
-		DRM_ERROR("Invalid framebuffer format %d\n", mode_cmd->depth);
+		DRM_ERROR("Invalid framebuffer format %s\n",
+			  drm_get_format_name(mode_cmd->pixel_format, &format_name));
 		return -EINVAL;
 	}
 
-	content_base_size.width  = mode_cmd->pitch / bytes_pp;
+	content_base_size.width  = mode_cmd->pitches[0] / bytes_pp;
 	content_base_size.height = mode_cmd->height;
 	content_base_size.depth  = 1;
 
@@ -826,16 +825,17 @@ static int vmw_create_dmabuf_proxy(struct drm_device *dev,
 static int vmw_kms_new_framebuffer_dmabuf(struct vmw_private *dev_priv,
 					  struct vmw_dma_buffer *dmabuf,
 					  struct vmw_framebuffer **out,
-					  const struct drm_mode_fb_cmd
+					  const struct drm_mode_fb_cmd2
 					  *mode_cmd)
 
 {
 	struct drm_device *dev = dev_priv->dev;
 	struct vmw_framebuffer_dmabuf *vfbd;
 	unsigned int requested_size;
+	struct drm_format_name_buf format_name;
 	int ret;
 
-	requested_size = mode_cmd->height * mode_cmd->pitch;
+	requested_size = mode_cmd->height * mode_cmd->pitches[0];
 	if (unlikely(requested_size > dmabuf->base.num_pages * PAGE_SIZE)) {
 		DRM_ERROR("Screen buffer object size is too small "
 			  "for requested mode.\n");
@@ -844,27 +844,16 @@ static int vmw_kms_new_framebuffer_dmabuf(struct vmw_private *dev_priv,
 
 	/* Limited framebuffer color depth support for screen objects */
 	if (dev_priv->active_display_unit == vmw_du_screen_object) {
-		switch (mode_cmd->depth) {
-		case 32:
-		case 24:
-			/* Only support 32 bpp for 32 and 24 depth fbs */
-			if (mode_cmd->bpp == 32)
-				break;
-
-			DRM_ERROR("Invalid color depth/bbp: %d %d\n",
-				  mode_cmd->depth, mode_cmd->bpp);
-			return -EINVAL;
-		case 16:
-		case 15:
-			/* Only support 16 bpp for 16 and 15 depth fbs */
-			if (mode_cmd->bpp == 16)
-				break;
-
-			DRM_ERROR("Invalid color depth/bbp: %d %d\n",
-				  mode_cmd->depth, mode_cmd->bpp);
-			return -EINVAL;
+		switch (mode_cmd->pixel_format) {
+		case DRM_FORMAT_XRGB8888:
+		case DRM_FORMAT_ARGB8888:
+			break;
+		case DRM_FORMAT_XRGB1555:
+		case DRM_FORMAT_RGB565:
+			break;
 		default:
-			DRM_ERROR("Invalid color depth: %d\n", mode_cmd->depth);
+			DRM_ERROR("Invalid pixel format: %s\n",
+				  drm_get_format_name(mode_cmd->pixel_format, &format_name));
 			return -EINVAL;
 		}
 	}
@@ -875,14 +864,10 @@ static int vmw_kms_new_framebuffer_dmabuf(struct vmw_private *dev_priv,
 		goto out_err1;
 	}
 
-	vfbd->base.base.bits_per_pixel = mode_cmd->bpp;
-	vfbd->base.base.pitches[0] = mode_cmd->pitch;
-	vfbd->base.base.depth = mode_cmd->depth;
-	vfbd->base.base.width = mode_cmd->width;
-	vfbd->base.base.height = mode_cmd->height;
+	drm_helper_mode_fill_fb_struct(&vfbd->base.base, mode_cmd);
 	vfbd->base.dmabuf = true;
 	vfbd->buffer = vmw_dmabuf_reference(dmabuf);
-	vfbd->base.user_handle = mode_cmd->handle;
+	vfbd->base.user_handle = mode_cmd->handles[0];
 	*out = &vfbd->base;
 
 	ret = drm_framebuffer_init(dev, &vfbd->base.base,
@@ -916,7 +901,7 @@ vmw_kms_new_framebuffer(struct vmw_private *dev_priv,
 			struct vmw_dma_buffer *dmabuf,
 			struct vmw_surface *surface,
 			bool only_2d,
-			const struct drm_mode_fb_cmd *mode_cmd)
+			const struct drm_mode_fb_cmd2 *mode_cmd)
 {
 	struct vmw_framebuffer *vfb = NULL;
 	bool is_dmabuf_proxy = false;
@@ -971,7 +956,7 @@ vmw_kms_new_framebuffer(struct vmw_private *dev_priv,
 
 static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
 						 struct drm_file *file_priv,
-						 const struct drm_mode_fb_cmd2 *mode_cmd2)
+						 const struct drm_mode_fb_cmd2 *mode_cmd)
 {
 	struct vmw_private *dev_priv = vmw_priv(dev);
 	struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
@@ -979,25 +964,8 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
 	struct vmw_surface *surface = NULL;
 	struct vmw_dma_buffer *bo = NULL;
 	struct ttm_base_object *user_obj;
-	struct drm_mode_fb_cmd mode_cmd;
-	const struct drm_format_info *info;
 	int ret;
 
-	info = drm_format_info(mode_cmd2->pixel_format);
-	if (!info || !info->depth) {
-		struct drm_format_name_buf format_name;
-		DRM_ERROR("Unsupported framebuffer format %s\n",
-		          drm_get_format_name(mode_cmd2->pixel_format, &format_name));
-		return ERR_PTR(-EINVAL);
-	}
-
-	mode_cmd.width = mode_cmd2->width;
-	mode_cmd.height = mode_cmd2->height;
-	mode_cmd.pitch = mode_cmd2->pitches[0];
-	mode_cmd.handle = mode_cmd2->handles[0];
-	mode_cmd.depth = info->depth;
-	mode_cmd.bpp = info->cpp[0] * 8;
-
 	/**
 	 * This code should be conditioned on Screen Objects not being used.
 	 * If screen objects are used, we can allocate a GMR to hold the
@@ -1005,8 +973,8 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
 	 */
 
 	if (!vmw_kms_validate_mode_vram(dev_priv,
-					mode_cmd.pitch,
-					mode_cmd.height)) {
+					mode_cmd->pitches[0],
+					mode_cmd->height)) {
 		DRM_ERROR("Requested mode exceed bounding box limit.\n");
 		return ERR_PTR(-ENOMEM);
 	}
@@ -1020,7 +988,7 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
 	 * command stream using user-space handles.
 	 */
 
-	user_obj = ttm_base_object_lookup(tfile, mode_cmd.handle);
+	user_obj = ttm_base_object_lookup(tfile, mode_cmd->handles[0]);
 	if (unlikely(user_obj == NULL)) {
 		DRM_ERROR("Could not locate requested kms frame buffer.\n");
 		return ERR_PTR(-ENOENT);
@@ -1032,14 +1000,14 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev,
 
 	/* returns either a dmabuf or surface */
 	ret = vmw_user_lookup_handle(dev_priv, tfile,
-				     mode_cmd.handle,
+				     mode_cmd->handles[0],
 				     &surface, &bo);
 	if (ret)
 		goto err_out;
 
 	vfb = vmw_kms_new_framebuffer(dev_priv, bo, surface,
 				      !(dev_priv->capabilities & SVGA_CAP_3D),
-				      &mode_cmd);
+				      mode_cmd);
 	if (IS_ERR(vfb)) {
 		ret = PTR_ERR(vfb);
 		goto err_out;

drivers/gpu/drm/vmwgfx/vmwgfx_kms.h

@@ -248,7 +248,7 @@ vmw_kms_new_framebuffer(struct vmw_private *dev_priv,
 			struct vmw_dma_buffer *dmabuf,
 			struct vmw_surface *surface,
 			bool only_2d,
-			const struct drm_mode_fb_cmd *mode_cmd);
+			const struct drm_mode_fb_cmd2 *mode_cmd);
 int vmw_kms_fbdev_init_data(struct vmw_private *dev_priv,
 			    unsigned unit,
 			    u32 max_width,

include/drm/drm_connector.h

@@ -262,6 +262,9 @@ struct drm_connector_funcs {
 	 * connector due to a user request. force can be used by the driver to
 	 * avoid expensive, destructive operations during automated probing.
 	 *
+	 * This callback is optional, if not implemented the connector will be
+	 * considered as always being attached.
+	 *
 	 * FIXME:
 	 *
 	 * Note that this hook is only called by the probe helper. It's not in