linux-next/drivers/gpu/drm/drm_crtc.c

/*
 * Copyright (c) 2006-2008 Intel Corporation
 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
 * Copyright (c) 2008 Red Hat Inc.
 *
 * DRM core CRTC related functions
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 *
 * Authors:
 *      Keith Packard
 *	Eric Anholt <eric@anholt.net>
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */
#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_edid.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_modeset_lock.h>
#include <drm/drm_atomic.h>
#include <drm/drm_auth.h>
#include <drm/drm_debugfs_crc.h>

#include "drm_crtc_internal.h"
#include "drm_internal.h"

/*
 * Global properties
 */
static const struct drm_prop_enum_list drm_plane_type_enum_list[] = {
	{ DRM_PLANE_TYPE_OVERLAY, "Overlay" },
	{ DRM_PLANE_TYPE_PRIMARY, "Primary" },
	{ DRM_PLANE_TYPE_CURSOR, "Cursor" },
};

/*
 * Optional properties
 */
/**
 * drm_crtc_force_disable - Forcibly turn off a CRTC
 * @crtc: CRTC to turn off
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_crtc_force_disable(struct drm_crtc *crtc)
{
	struct drm_mode_set set = {
		.crtc = crtc,
	};

	return drm_mode_set_config_internal(&set);
}
EXPORT_SYMBOL(drm_crtc_force_disable);

/**
 * drm_crtc_force_disable_all - Forcibly turn off all enabled CRTCs
 * @dev: DRM device whose CRTCs to turn off
 *
 * Drivers may want to call this on unload to ensure that all displays are
 * unlit and the GPU is in a consistent, low power state. Takes modeset locks.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_crtc_force_disable_all(struct drm_device *dev)
{
	struct drm_crtc *crtc;
	int ret = 0;

	drm_modeset_lock_all(dev);
	drm_for_each_crtc(crtc, dev)
		if (crtc->enabled) {
			ret = drm_crtc_force_disable(crtc);
			if (ret)
				goto out;
		}
out:
	drm_modeset_unlock_all(dev);
	return ret;
}
EXPORT_SYMBOL(drm_crtc_force_disable_all);

static unsigned int drm_num_crtcs(struct drm_device *dev)
{
	unsigned int num = 0;
	struct drm_crtc *tmp;

	drm_for_each_crtc(tmp, dev) {
		num++;
	}

	return num;
}

static int drm_crtc_register_all(struct drm_device *dev)
{
	struct drm_crtc *crtc;
	int ret = 0;

	drm_for_each_crtc(crtc, dev) {
		if (drm_debugfs_crtc_add(crtc))
			DRM_ERROR("Failed to initialize debugfs entry for CRTC '%s'.\n",
				  crtc->name);

		if (crtc->funcs->late_register)
			ret = crtc->funcs->late_register(crtc);
		if (ret)
			return ret;
	}

	return 0;
}

static void drm_crtc_unregister_all(struct drm_device *dev)
{
	struct drm_crtc *crtc;

	drm_for_each_crtc(crtc, dev) {
		if (crtc->funcs->early_unregister)
			crtc->funcs->early_unregister(crtc);
		drm_debugfs_crtc_remove(crtc);
	}
}

static int drm_crtc_crc_init(struct drm_crtc *crtc)
{
#ifdef CONFIG_DEBUG_FS
	spin_lock_init(&crtc->crc.lock);
	init_waitqueue_head(&crtc->crc.wq);
	crtc->crc.source = kstrdup("auto", GFP_KERNEL);
	if (!crtc->crc.source)
		return -ENOMEM;
#endif
	return 0;
}

static void drm_crtc_crc_fini(struct drm_crtc *crtc)
{
#ifdef CONFIG_DEBUG_FS
	kfree(crtc->crc.source);
#endif
}

/**
 * drm_crtc_init_with_planes - Initialise a new CRTC object with
 *    specified primary and cursor planes.
 * @dev: DRM device
 * @crtc: CRTC object to init
 * @primary: Primary plane for CRTC
 * @cursor: Cursor plane for CRTC
 * @funcs: callbacks for the new CRTC
 * @name: printf style format string for the CRTC name, or NULL for default name
 *
 * Inits a new object created as base part of a driver crtc object. Drivers
 * should use this function instead of drm_crtc_init(), which is only provided
 * for backwards compatibility with drivers which do not yet support universal
 * planes). For really simple hardware which has only 1 plane look at
 * drm_simple_display_pipe_init() instead.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
			      struct drm_plane *primary,
			      struct drm_plane *cursor,
			      const struct drm_crtc_funcs *funcs,
			      const char *name, ...)
{
	struct drm_mode_config *config = &dev->mode_config;
	int ret;

	WARN_ON(primary && primary->type != DRM_PLANE_TYPE_PRIMARY);
	WARN_ON(cursor && cursor->type != DRM_PLANE_TYPE_CURSOR);

	crtc->dev = dev;
	crtc->funcs = funcs;

	INIT_LIST_HEAD(&crtc->commit_list);
	spin_lock_init(&crtc->commit_lock);

	drm_modeset_lock_init(&crtc->mutex);
	ret = drm_mode_object_get(dev, &crtc->base, DRM_MODE_OBJECT_CRTC);
	if (ret)
		return ret;

	if (name) {
		va_list ap;

		va_start(ap, name);
		crtc->name = kvasprintf(GFP_KERNEL, name, ap);
		va_end(ap);
	} else {
		crtc->name = kasprintf(GFP_KERNEL, "crtc-%d",
				       drm_num_crtcs(dev));
	}
	if (!crtc->name) {
		drm_mode_object_unregister(dev, &crtc->base);
		return -ENOMEM;
	}

	crtc->base.properties = &crtc->properties;

	list_add_tail(&crtc->head, &config->crtc_list);
	crtc->index = config->num_crtc++;

	crtc->primary = primary;
	crtc->cursor = cursor;
	if (primary && !primary->possible_crtcs)
		primary->possible_crtcs = 1 << drm_crtc_index(crtc);
	if (cursor && !cursor->possible_crtcs)
		cursor->possible_crtcs = 1 << drm_crtc_index(crtc);

	ret = drm_crtc_crc_init(crtc);
	if (ret) {
		drm_mode_object_unregister(dev, &crtc->base);
		return ret;
	}

	if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
		drm_object_attach_property(&crtc->base, config->prop_active, 0);
		drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
	}

	return 0;
}
EXPORT_SYMBOL(drm_crtc_init_with_planes);

/**
 * drm_crtc_cleanup - Clean up the core crtc usage
 * @crtc: CRTC to cleanup
 *
 * This function cleans up @crtc and removes it from the DRM mode setting
 * core. Note that the function does *not* free the crtc structure itself,
 * this is the responsibility of the caller.
 */
void drm_crtc_cleanup(struct drm_crtc *crtc)
{
	struct drm_device *dev = crtc->dev;

	/* Note that the crtc_list is considered to be static; should we
	 * remove the drm_crtc at runtime we would have to decrement all
	 * the indices on the drm_crtc after us in the crtc_list.
	 */

	drm_crtc_crc_fini(crtc);

	kfree(crtc->gamma_store);
	crtc->gamma_store = NULL;

	drm_modeset_lock_fini(&crtc->mutex);

	drm_mode_object_unregister(dev, &crtc->base);
	list_del(&crtc->head);
	dev->mode_config.num_crtc--;

	WARN_ON(crtc->state && !crtc->funcs->atomic_destroy_state);
	if (crtc->state && crtc->funcs->atomic_destroy_state)
		crtc->funcs->atomic_destroy_state(crtc, crtc->state);

	kfree(crtc->name);

	memset(crtc, 0, sizeof(*crtc));
}
EXPORT_SYMBOL(drm_crtc_cleanup);

int drm_modeset_register_all(struct drm_device *dev)
{
	int ret;

	ret = drm_plane_register_all(dev);
	if (ret)
		goto err_plane;

	ret = drm_crtc_register_all(dev);
	if  (ret)
		goto err_crtc;

	ret = drm_encoder_register_all(dev);
	if (ret)
		goto err_encoder;

	ret = drm_connector_register_all(dev);
	if (ret)
		goto err_connector;

	return 0;

err_connector:
	drm_encoder_unregister_all(dev);
err_encoder:
	drm_crtc_unregister_all(dev);
err_crtc:
	drm_plane_unregister_all(dev);
err_plane:
	return ret;
}

void drm_modeset_unregister_all(struct drm_device *dev)
{
	drm_connector_unregister_all(dev);
	drm_encoder_unregister_all(dev);
	drm_crtc_unregister_all(dev);
	drm_plane_unregister_all(dev);
}

static int drm_mode_create_standard_properties(struct drm_device *dev)
{
	struct drm_property *prop;
	int ret;

	ret = drm_connector_create_standard_properties(dev);
	if (ret)
		return ret;

	prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
					"type", drm_plane_type_enum_list,
					ARRAY_SIZE(drm_plane_type_enum_list));
	if (!prop)
		return -ENOMEM;
	dev->mode_config.plane_type_property = prop;

	prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
			"SRC_X", 0, UINT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_src_x = prop;

	prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
			"SRC_Y", 0, UINT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_src_y = prop;

	prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
			"SRC_W", 0, UINT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_src_w = prop;

	prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
			"SRC_H", 0, UINT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_src_h = prop;

	prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
			"CRTC_X", INT_MIN, INT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_crtc_x = prop;

	prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
			"CRTC_Y", INT_MIN, INT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_crtc_y = prop;

	prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
			"CRTC_W", 0, INT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_crtc_w = prop;

	prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
			"CRTC_H", 0, INT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_crtc_h = prop;

	prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
			"FB_ID", DRM_MODE_OBJECT_FB);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_fb_id = prop;

	prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
			"CRTC_ID", DRM_MODE_OBJECT_CRTC);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_crtc_id = prop;

	prop = drm_property_create_bool(dev, DRM_MODE_PROP_ATOMIC,
			"ACTIVE");
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_active = prop;

	prop = drm_property_create(dev,
			DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_BLOB,
			"MODE_ID", 0);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.prop_mode_id = prop;

	prop = drm_property_create(dev,
			DRM_MODE_PROP_BLOB,
			"DEGAMMA_LUT", 0);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.degamma_lut_property = prop;

	prop = drm_property_create_range(dev,
			DRM_MODE_PROP_IMMUTABLE,
			"DEGAMMA_LUT_SIZE", 0, UINT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.degamma_lut_size_property = prop;

	prop = drm_property_create(dev,
			DRM_MODE_PROP_BLOB,
			"CTM", 0);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.ctm_property = prop;

	prop = drm_property_create(dev,
			DRM_MODE_PROP_BLOB,
			"GAMMA_LUT", 0);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.gamma_lut_property = prop;

	prop = drm_property_create_range(dev,
			DRM_MODE_PROP_IMMUTABLE,
			"GAMMA_LUT_SIZE", 0, UINT_MAX);
	if (!prop)
		return -ENOMEM;
	dev->mode_config.gamma_lut_size_property = prop;

	return 0;
}

/**
 * drm_mode_getresources - get graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a set of configuration description structures and return
 * them to the user, including CRTC, connector and framebuffer configuration.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getresources(struct drm_device *dev, void *data,
			  struct drm_file *file_priv)
{
	struct drm_mode_card_res *card_res = data;
	struct list_head *lh;
	struct drm_framebuffer *fb;
	struct drm_connector *connector;
	struct drm_crtc *crtc;
	struct drm_encoder *encoder;
	int ret = 0;
	int connector_count = 0;
	int crtc_count = 0;
	int fb_count = 0;
	int encoder_count = 0;
	int copied = 0;
	uint32_t __user *fb_id;
	uint32_t __user *crtc_id;
	uint32_t __user *connector_id;
	uint32_t __user *encoder_id;

	if (!drm_core_check_feature(dev, DRIVER_MODESET))
		return -EINVAL;


	mutex_lock(&file_priv->fbs_lock);
	/*
	 * For the non-control nodes we need to limit the list of resources
	 * by IDs in the group list for this node
	 */
	list_for_each(lh, &file_priv->fbs)
		fb_count++;

	/* handle this in 4 parts */
	/* FBs */
	if (card_res->count_fbs >= fb_count) {
		copied = 0;
		fb_id = (uint32_t __user *)(unsigned long)card_res->fb_id_ptr;
		list_for_each_entry(fb, &file_priv->fbs, filp_head) {
			if (put_user(fb->base.id, fb_id + copied)) {
				mutex_unlock(&file_priv->fbs_lock);
				return -EFAULT;
			}
			copied++;
		}
	}
	card_res->count_fbs = fb_count;
	mutex_unlock(&file_priv->fbs_lock);

	/* mode_config.mutex protects the connector list against e.g. DP MST
	 * connector hot-adding. CRTC/Plane lists are invariant. */
	mutex_lock(&dev->mode_config.mutex);
	drm_for_each_crtc(crtc, dev)
		crtc_count++;

	drm_for_each_connector(connector, dev)
		connector_count++;

	drm_for_each_encoder(encoder, dev)
		encoder_count++;

	card_res->max_height = dev->mode_config.max_height;
	card_res->min_height = dev->mode_config.min_height;
	card_res->max_width = dev->mode_config.max_width;
	card_res->min_width = dev->mode_config.min_width;

	/* CRTCs */
	if (card_res->count_crtcs >= crtc_count) {
		copied = 0;
		crtc_id = (uint32_t __user *)(unsigned long)card_res->crtc_id_ptr;
		drm_for_each_crtc(crtc, dev) {
			if (put_user(crtc->base.id, crtc_id + copied)) {
				ret = -EFAULT;
				goto out;
			}
			copied++;
		}
	}
	card_res->count_crtcs = crtc_count;

	/* Encoders */
	if (card_res->count_encoders >= encoder_count) {
		copied = 0;
		encoder_id = (uint32_t __user *)(unsigned long)card_res->encoder_id_ptr;
		drm_for_each_encoder(encoder, dev) {
			if (put_user(encoder->base.id, encoder_id +
				     copied)) {
				ret = -EFAULT;
				goto out;
			}
			copied++;
		}
	}
	card_res->count_encoders = encoder_count;

	/* Connectors */
	if (card_res->count_connectors >= connector_count) {
		copied = 0;
		connector_id = (uint32_t __user *)(unsigned long)card_res->connector_id_ptr;
		drm_for_each_connector(connector, dev) {
			if (put_user(connector->base.id,
				     connector_id + copied)) {
				ret = -EFAULT;
				goto out;
			}
			copied++;
		}
	}
	card_res->count_connectors = connector_count;

out:
	mutex_unlock(&dev->mode_config.mutex);
	return ret;
}

/**
 * drm_mode_getcrtc - get CRTC configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a CRTC configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getcrtc(struct drm_device *dev,
		     void *data, struct drm_file *file_priv)
{
	struct drm_mode_crtc *crtc_resp = data;
	struct drm_crtc *crtc;

	if (!drm_core_check_feature(dev, DRIVER_MODESET))
		return -EINVAL;

	crtc = drm_crtc_find(dev, crtc_resp->crtc_id);
	if (!crtc)
		return -ENOENT;

	drm_modeset_lock_crtc(crtc, crtc->primary);
	crtc_resp->gamma_size = crtc->gamma_size;
	if (crtc->primary->fb)
		crtc_resp->fb_id = crtc->primary->fb->base.id;
	else
		crtc_resp->fb_id = 0;

	if (crtc->state) {
		crtc_resp->x = crtc->primary->state->src_x >> 16;
		crtc_resp->y = crtc->primary->state->src_y >> 16;
		if (crtc->state->enable) {
			drm_mode_convert_to_umode(&crtc_resp->mode, &crtc->state->mode);
			crtc_resp->mode_valid = 1;

		} else {
			crtc_resp->mode_valid = 0;
		}
	} else {
		crtc_resp->x = crtc->x;
		crtc_resp->y = crtc->y;
		if (crtc->enabled) {
			drm_mode_convert_to_umode(&crtc_resp->mode, &crtc->mode);
			crtc_resp->mode_valid = 1;

		} else {
			crtc_resp->mode_valid = 0;
		}
	}
	drm_modeset_unlock_crtc(crtc);

	return 0;
}

/**
 * drm_mode_set_config_internal - helper to call ->set_config
 * @set: modeset config to set
 *
 * This is a little helper to wrap internal calls to the ->set_config driver
 * interface. The only thing it adds is correct refcounting dance.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_set_config_internal(struct drm_mode_set *set)
{
	struct drm_crtc *crtc = set->crtc;
	struct drm_framebuffer *fb;
	struct drm_crtc *tmp;
	int ret;

	/*
	 * NOTE: ->set_config can also disable other crtcs (if we steal all
	 * connectors from it), hence we need to refcount the fbs across all
	 * crtcs. Atomic modeset will have saner semantics ...
	 */
	drm_for_each_crtc(tmp, crtc->dev)
		tmp->primary->old_fb = tmp->primary->fb;

	fb = set->fb;

	ret = crtc->funcs->set_config(set);
	if (ret == 0) {
		crtc->primary->crtc = crtc;
		crtc->primary->fb = fb;
	}

	drm_for_each_crtc(tmp, crtc->dev) {
		if (tmp->primary->fb)
			drm_framebuffer_reference(tmp->primary->fb);
		if (tmp->primary->old_fb)
			drm_framebuffer_unreference(tmp->primary->old_fb);
		tmp->primary->old_fb = NULL;
	}

	return ret;
}
EXPORT_SYMBOL(drm_mode_set_config_internal);

/**
 * drm_crtc_get_hv_timing - Fetches hdisplay/vdisplay for given mode
 * @mode: mode to query
 * @hdisplay: hdisplay value to fill in
 * @vdisplay: vdisplay value to fill in
 *
 * The vdisplay value will be doubled if the specified mode is a stereo mode of
 * the appropriate layout.
 */
void drm_crtc_get_hv_timing(const struct drm_display_mode *mode,
			    int *hdisplay, int *vdisplay)
{
	struct drm_display_mode adjusted;

	drm_mode_copy(&adjusted, mode);
	drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE_ONLY);
	*hdisplay = adjusted.crtc_hdisplay;
	*vdisplay = adjusted.crtc_vdisplay;
}
EXPORT_SYMBOL(drm_crtc_get_hv_timing);

/**
 * drm_crtc_check_viewport - Checks that a framebuffer is big enough for the
 *     CRTC viewport
 * @crtc: CRTC that framebuffer will be displayed on
 * @x: x panning
 * @y: y panning
 * @mode: mode that framebuffer will be displayed under
 * @fb: framebuffer to check size of
 */
int drm_crtc_check_viewport(const struct drm_crtc *crtc,
			    int x, int y,
			    const struct drm_display_mode *mode,
			    const struct drm_framebuffer *fb)

{
	int hdisplay, vdisplay;

	drm_crtc_get_hv_timing(mode, &hdisplay, &vdisplay);

	if (crtc->state &&
	    drm_rotation_90_or_270(crtc->primary->state->rotation))
		swap(hdisplay, vdisplay);

	return drm_framebuffer_check_src_coords(x << 16, y << 16,
						hdisplay << 16, vdisplay << 16,
						fb);
}
EXPORT_SYMBOL(drm_crtc_check_viewport);

/**
 * drm_mode_setcrtc - set CRTC configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Build a new CRTC configuration based on user request.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_setcrtc(struct drm_device *dev, void *data,
		     struct drm_file *file_priv)
{
	struct drm_mode_config *config = &dev->mode_config;
	struct drm_mode_crtc *crtc_req = data;
	struct drm_crtc *crtc;
	struct drm_connector **connector_set = NULL, *connector;
	struct drm_framebuffer *fb = NULL;
	struct drm_display_mode *mode = NULL;
	struct drm_mode_set set;
	uint32_t __user *set_connectors_ptr;
	int ret;
	int i;

	if (!drm_core_check_feature(dev, DRIVER_MODESET))
		return -EINVAL;

	/*
	 * Universal plane src offsets are only 16.16, prevent havoc for
	 * drivers using universal plane code internally.
	 */
	if (crtc_req->x & 0xffff0000 || crtc_req->y & 0xffff0000)
		return -ERANGE;

	drm_modeset_lock_all(dev);
	crtc = drm_crtc_find(dev, crtc_req->crtc_id);
	if (!crtc) {
		DRM_DEBUG_KMS("Unknown CRTC ID %d\n", crtc_req->crtc_id);
		ret = -ENOENT;
		goto out;
	}
	DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);

	if (crtc_req->mode_valid) {
		/* If we have a mode we need a framebuffer. */
		/* If we pass -1, set the mode with the currently bound fb */
		if (crtc_req->fb_id == -1) {
			if (!crtc->primary->fb) {
				DRM_DEBUG_KMS("CRTC doesn't have current FB\n");
				ret = -EINVAL;
				goto out;
			}
			fb = crtc->primary->fb;
			/* Make refcounting symmetric with the lookup path. */
			drm_framebuffer_reference(fb);
		} else {
			fb = drm_framebuffer_lookup(dev, crtc_req->fb_id);
			if (!fb) {
				DRM_DEBUG_KMS("Unknown FB ID%d\n",
						crtc_req->fb_id);
				ret = -ENOENT;
				goto out;
			}
		}

		mode = drm_mode_create(dev);
		if (!mode) {
			ret = -ENOMEM;
			goto out;
		}

		ret = drm_mode_convert_umode(mode, &crtc_req->mode);
		if (ret) {
			DRM_DEBUG_KMS("Invalid mode\n");
			goto out;
		}

		/*
		 * Check whether the primary plane supports the fb pixel format.
		 * Drivers not implementing the universal planes API use a
		 * default formats list provided by the DRM core which doesn't
		 * match real hardware capabilities. Skip the check in that
		 * case.
		 */
		if (!crtc->primary->format_default) {
			ret = drm_plane_check_pixel_format(crtc->primary,
							   fb->pixel_format);
			if (ret) {
				struct drm_format_name_buf format_name;
				DRM_DEBUG_KMS("Invalid pixel format %s\n",
				              drm_get_format_name(fb->pixel_format,
				                                  &format_name));
				goto out;
			}
		}

		ret = drm_crtc_check_viewport(crtc, crtc_req->x, crtc_req->y,
					      mode, fb);
		if (ret)
			goto out;

	}

	if (crtc_req->count_connectors == 0 && mode) {
		DRM_DEBUG_KMS("Count connectors is 0 but mode set\n");
		ret = -EINVAL;
		goto out;
	}

	if (crtc_req->count_connectors > 0 && (!mode || !fb)) {
		DRM_DEBUG_KMS("Count connectors is %d but no mode or fb set\n",
			  crtc_req->count_connectors);
		ret = -EINVAL;
		goto out;
	}

	if (crtc_req->count_connectors > 0) {
		u32 out_id;

		/* Avoid unbounded kernel memory allocation */
		if (crtc_req->count_connectors > config->num_connector) {
			ret = -EINVAL;
			goto out;
		}

		connector_set = kmalloc_array(crtc_req->count_connectors,
					      sizeof(struct drm_connector *),
					      GFP_KERNEL);
		if (!connector_set) {
			ret = -ENOMEM;
			goto out;
		}

		for (i = 0; i < crtc_req->count_connectors; i++) {
			connector_set[i] = NULL;
			set_connectors_ptr = (uint32_t __user *)(unsigned long)crtc_req->set_connectors_ptr;
			if (get_user(out_id, &set_connectors_ptr[i])) {
				ret = -EFAULT;
				goto out;
			}

			connector = drm_connector_lookup(dev, out_id);
			if (!connector) {
				DRM_DEBUG_KMS("Connector id %d unknown\n",
						out_id);
				ret = -ENOENT;
				goto out;
			}
			DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
					connector->base.id,
					connector->name);

			connector_set[i] = connector;
		}
	}

	set.crtc = crtc;
	set.x = crtc_req->x;
	set.y = crtc_req->y;
	set.mode = mode;
	set.connectors = connector_set;
	set.num_connectors = crtc_req->count_connectors;
	set.fb = fb;
	ret = drm_mode_set_config_internal(&set);

out:
	if (fb)
		drm_framebuffer_unreference(fb);

	if (connector_set) {
		for (i = 0; i < crtc_req->count_connectors; i++) {
			if (connector_set[i])
				drm_connector_unreference(connector_set[i]);
		}
	}
	kfree(connector_set);
	drm_mode_destroy(dev, mode);
	drm_modeset_unlock_all(dev);
	return ret;
}

int drm_mode_crtc_set_obj_prop(struct drm_mode_object *obj,
			       struct drm_property *property,
			       uint64_t value)
{
	int ret = -EINVAL;
	struct drm_crtc *crtc = obj_to_crtc(obj);

	if (crtc->funcs->set_property)
		ret = crtc->funcs->set_property(crtc, property, value);
	if (!ret)
		drm_object_property_set_value(obj, property, value);

	return ret;
}

/**
 * drm_mode_config_reset - call ->reset callbacks
 * @dev: drm device
 *
 * This functions calls all the crtc's, encoder's and connector's ->reset
 * callback. Drivers can use this in e.g. their driver load or resume code to
 * reset hardware and software state.
 */
void drm_mode_config_reset(struct drm_device *dev)
{
	struct drm_crtc *crtc;
	struct drm_plane *plane;
	struct drm_encoder *encoder;
	struct drm_connector *connector;

	drm_for_each_plane(plane, dev)
		if (plane->funcs->reset)
			plane->funcs->reset(plane);

	drm_for_each_crtc(crtc, dev)
		if (crtc->funcs->reset)
			crtc->funcs->reset(crtc);

	drm_for_each_encoder(encoder, dev)
		if (encoder->funcs->reset)
			encoder->funcs->reset(encoder);

	mutex_lock(&dev->mode_config.mutex);
	drm_for_each_connector(connector, dev)
		if (connector->funcs->reset)
			connector->funcs->reset(connector);
	mutex_unlock(&dev->mode_config.mutex);
}
EXPORT_SYMBOL(drm_mode_config_reset);

/**
 * drm_mode_config_init - initialize DRM mode_configuration structure
 * @dev: DRM device
 *
 * Initialize @dev's mode_config structure, used for tracking the graphics
 * configuration of @dev.
 *
 * Since this initializes the modeset locks, no locking is possible. Which is no
 * problem, since this should happen single threaded at init time. It is the
 * driver's problem to ensure this guarantee.
 *
 */
void drm_mode_config_init(struct drm_device *dev)
{
	mutex_init(&dev->mode_config.mutex);
	drm_modeset_lock_init(&dev->mode_config.connection_mutex);
	mutex_init(&dev->mode_config.idr_mutex);
	mutex_init(&dev->mode_config.fb_lock);
	mutex_init(&dev->mode_config.blob_lock);
	INIT_LIST_HEAD(&dev->mode_config.fb_list);
	INIT_LIST_HEAD(&dev->mode_config.crtc_list);
	INIT_LIST_HEAD(&dev->mode_config.connector_list);
	INIT_LIST_HEAD(&dev->mode_config.encoder_list);
	INIT_LIST_HEAD(&dev->mode_config.property_list);
	INIT_LIST_HEAD(&dev->mode_config.property_blob_list);
	INIT_LIST_HEAD(&dev->mode_config.plane_list);
	idr_init(&dev->mode_config.crtc_idr);
	idr_init(&dev->mode_config.tile_idr);
	ida_init(&dev->mode_config.connector_ida);

	drm_modeset_lock_all(dev);
	drm_mode_create_standard_properties(dev);
	drm_modeset_unlock_all(dev);

	/* Just to be sure */
	dev->mode_config.num_fb = 0;
	dev->mode_config.num_connector = 0;
	dev->mode_config.num_crtc = 0;
	dev->mode_config.num_encoder = 0;
	dev->mode_config.num_overlay_plane = 0;
	dev->mode_config.num_total_plane = 0;
}
EXPORT_SYMBOL(drm_mode_config_init);

/**
 * drm_mode_config_cleanup - free up DRM mode_config info
 * @dev: DRM device
 *
 * Free up all the connectors and CRTCs associated with this DRM device, then
 * free up the framebuffers and associated buffer objects.
 *
 * Note that since this /should/ happen single-threaded at driver/device
 * teardown time, no locking is required. It's the driver's job to ensure that
 * this guarantee actually holds true.
 *
 * FIXME: cleanup any dangling user buffer objects too
 */
void drm_mode_config_cleanup(struct drm_device *dev)
{
	struct drm_connector *connector, *ot;
	struct drm_crtc *crtc, *ct;
	struct drm_encoder *encoder, *enct;
	struct drm_framebuffer *fb, *fbt;
	struct drm_property *property, *pt;
	struct drm_property_blob *blob, *bt;
	struct drm_plane *plane, *plt;

	list_for_each_entry_safe(encoder, enct, &dev->mode_config.encoder_list,
				 head) {
		encoder->funcs->destroy(encoder);
	}

	list_for_each_entry_safe(connector, ot,
				 &dev->mode_config.connector_list, head) {
		connector->funcs->destroy(connector);
	}

	list_for_each_entry_safe(property, pt, &dev->mode_config.property_list,
				 head) {
		drm_property_destroy(dev, property);
	}

	list_for_each_entry_safe(plane, plt, &dev->mode_config.plane_list,
				 head) {
		plane->funcs->destroy(plane);
	}

	list_for_each_entry_safe(crtc, ct, &dev->mode_config.crtc_list, head) {
		crtc->funcs->destroy(crtc);
	}

	list_for_each_entry_safe(blob, bt, &dev->mode_config.property_blob_list,
				 head_global) {
		drm_property_unreference_blob(blob);
	}

	/*
	 * Single-threaded teardown context, so it's not required to grab the
	 * fb_lock to protect against concurrent fb_list access. Contrary, it
	 * would actually deadlock with the drm_framebuffer_cleanup function.
	 *
	 * Also, if there are any framebuffers left, that's a driver leak now,
	 * so politely WARN about this.
	 */
	WARN_ON(!list_empty(&dev->mode_config.fb_list));
	list_for_each_entry_safe(fb, fbt, &dev->mode_config.fb_list, head) {
		drm_framebuffer_free(&fb->base.refcount);
	}

	ida_destroy(&dev->mode_config.connector_ida);
	idr_destroy(&dev->mode_config.tile_idr);
	idr_destroy(&dev->mode_config.crtc_idr);
	drm_modeset_lock_fini(&dev->mode_config.connection_mutex);
}
EXPORT_SYMBOL(drm_mode_config_cleanup);

/**
 * DOC: Tile group
 *
 * Tile groups are used to represent tiled monitors with a unique
 * integer identifier. Tiled monitors using DisplayID v1.3 have
 * a unique 8-byte handle, we store this in a tile group, so we
 * have a common identifier for all tiles in a monitor group.
 */
static void drm_tile_group_free(struct kref *kref)
{
	struct drm_tile_group *tg = container_of(kref, struct drm_tile_group, refcount);
	struct drm_device *dev = tg->dev;
	mutex_lock(&dev->mode_config.idr_mutex);
	idr_remove(&dev->mode_config.tile_idr, tg->id);
	mutex_unlock(&dev->mode_config.idr_mutex);
	kfree(tg);
}

/**
 * drm_mode_put_tile_group - drop a reference to a tile group.
 * @dev: DRM device
 * @tg: tile group to drop reference to.
 *
 * drop reference to tile group and free if 0.
 */
void drm_mode_put_tile_group(struct drm_device *dev,
			     struct drm_tile_group *tg)
{
	kref_put(&tg->refcount, drm_tile_group_free);
}

/**
 * drm_mode_get_tile_group - get a reference to an existing tile group
 * @dev: DRM device
 * @topology: 8-bytes unique per monitor.
 *
 * Use the unique bytes to get a reference to an existing tile group.
 *
 * RETURNS:
 * tile group or NULL if not found.
 */
struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
					       char topology[8])
{
	struct drm_tile_group *tg;
	int id;
	mutex_lock(&dev->mode_config.idr_mutex);
	idr_for_each_entry(&dev->mode_config.tile_idr, tg, id) {
		if (!memcmp(tg->group_data, topology, 8)) {
			if (!kref_get_unless_zero(&tg->refcount))
				tg = NULL;
			mutex_unlock(&dev->mode_config.idr_mutex);
			return tg;
		}
	}
	mutex_unlock(&dev->mode_config.idr_mutex);
	return NULL;
}
EXPORT_SYMBOL(drm_mode_get_tile_group);

/**
 * drm_mode_create_tile_group - create a tile group from a displayid description
 * @dev: DRM device
 * @topology: 8-bytes unique per monitor.
 *
 * Create a tile group for the unique monitor, and get a unique
 * identifier for the tile group.
 *
 * RETURNS:
 * new tile group or error.
 */
struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
						  char topology[8])
{
	struct drm_tile_group *tg;
	int ret;

	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
	if (!tg)
		return ERR_PTR(-ENOMEM);

	kref_init(&tg->refcount);
	memcpy(tg->group_data, topology, 8);
	tg->dev = dev;

	mutex_lock(&dev->mode_config.idr_mutex);
	ret = idr_alloc(&dev->mode_config.tile_idr, tg, 1, 0, GFP_KERNEL);
	if (ret >= 0) {
		tg->id = ret;
	} else {
		kfree(tg);
		tg = ERR_PTR(ret);
	}

	mutex_unlock(&dev->mode_config.idr_mutex);
	return tg;
}
EXPORT_SYMBOL(drm_mode_create_tile_group);