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/*

 * Copyright (c) 2006-2008 Intel Corporation

 * Copyright (c) 2007 Dave Airlie 

 *

 * 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 

 *      Dave Airlie 

 *      Jesse Barnes 

 */

#include "drmP.h"

#include "drm_crtc.h"

#include "drm_crtc_helper.h"

/*

 * Detailed mode info for 800x600@60Hz

 */

static struct drm_display_mode std_modes[] = {

	{ DRM_MODE("800x600", DRM_MODE_TYPE_DEFAULT, 40000, 800, 840,

		   968, 1056, 0, 600, 601, 605, 628, 0,

		   DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC) },

};

static void drm_mode_validate_flag(struct drm_connector *connector,

				   int flags)

{

	struct drm_display_mode *mode, *t;

	if (flags == (DRM_MODE_FLAG_DBLSCAN | DRM_MODE_FLAG_INTERLACE))

		return;

	list_for_each_entry_safe(mode, t, &connector->modes, head) {

		if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&

				!(flags & DRM_MODE_FLAG_INTERLACE))

			mode->status = MODE_NO_INTERLACE;

		if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&

				!(flags & DRM_MODE_FLAG_DBLSCAN))

			mode->status = MODE_NO_DBLESCAN;

	}

	return;

}

/**

 * drm_helper_probe_connector_modes - get complete set of display modes

 * @dev: DRM device

 * @maxX: max width for modes

 * @maxY: max height for modes

 *

 * LOCKING:

 * Caller must hold mode config lock.

 *

 * Based on @dev's mode_config layout, scan all the connectors and try to detect

 * modes on them.  Modes will first be added to the connector's probed_modes

 * list, then culled (based on validity and the @maxX, @maxY parameters) and

 * put into the normal modes list.

 *

 * Intended to be used either at bootup time or when major configuration

 * changes have occurred.

 *

 * FIXME: take into account monitor limits

 *

 * RETURNS:

 * Number of modes found on @connector.

 */

int drm_helper_probe_single_connector_modes(struct drm_connector *connector,

					    uint32_t maxX, uint32_t maxY)

{

	struct drm_device *dev = connector->dev;

	struct drm_display_mode *mode, *t;

	struct drm_connector_helper_funcs *connector_funcs =

		connector->helper_private;

	int count = 0;

	int mode_flags = 0;

	DRM_DEBUG("%s\n", drm_get_connector_name(connector));

	/* set all modes to the unverified state */

	list_for_each_entry_safe(mode, t, &connector->modes, head)

		mode->status = MODE_UNVERIFIED;

	connector->status = connector->funcs->detect(connector);

	if (connector->status == connector_status_disconnected) {

		DRM_DEBUG("%s is disconnected\n",

			  drm_get_connector_name(connector));

		/* TODO set EDID to NULL */

		return 0;

	}

	count = (*connector_funcs->get_modes)(connector);

	if (!count)

		return 0;

	drm_mode_connector_list_update(connector);

	if (maxX && maxY)

		drm_mode_validate_size(dev, &connector->modes, maxX,

				       maxY, 0);

	if (connector->interlace_allowed)

		mode_flags |= DRM_MODE_FLAG_INTERLACE;

	if (connector->doublescan_allowed)

		mode_flags |= DRM_MODE_FLAG_DBLSCAN;

	drm_mode_validate_flag(connector, mode_flags);

	list_for_each_entry_safe(mode, t, &connector->modes, head) {

		if (mode->status == MODE_OK)

			mode->status = connector_funcs->mode_valid(connector,

								   mode);

	}

	drm_mode_prune_invalid(dev, &connector->modes, true);

	if (list_empty(&connector->modes))

		return 0;

	drm_mode_sort(&connector->modes);

	DRM_DEBUG("Probed modes for %s\n", drm_get_connector_name(connector));

	list_for_each_entry_safe(mode, t, &connector->modes, head) {

		mode->vrefresh = drm_mode_vrefresh(mode);

		drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);

		drm_mode_debug_printmodeline(mode);

	}

	return count;

}

EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);

int drm_helper_probe_connector_modes(struct drm_device *dev, uint32_t maxX,

				      uint32_t maxY)

{

	struct drm_connector *connector;

	int count = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		count += drm_helper_probe_single_connector_modes(connector,

								 maxX, maxY);

	}

	return count;

}

EXPORT_SYMBOL(drm_helper_probe_connector_modes);

static void drm_helper_add_std_modes(struct drm_device *dev,

				     struct drm_connector *connector)

{

	struct drm_display_mode *mode, *t;

	int i;

	for (i = 0; i < ARRAY_SIZE(std_modes); i++) {

		struct drm_display_mode *stdmode;

		/*

		 * When no valid EDID modes are available we end up

		 * here and bailed in the past, now we add some standard

		 * modes and move on.

		 */

		stdmode = drm_mode_duplicate(dev, &std_modes[i]);

		drm_mode_probed_add(connector, stdmode);

		drm_mode_list_concat(&connector->probed_modes,

				     &connector->modes);

		DRM_DEBUG("Adding mode %s to %s\n", stdmode->name,

			  drm_get_connector_name(connector));

	}

	drm_mode_sort(&connector->modes);

	DRM_DEBUG("Added std modes on %s\n", drm_get_connector_name(connector));

	list_for_each_entry_safe(mode, t, &connector->modes, head) {

		mode->vrefresh = drm_mode_vrefresh(mode);

		drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);

		drm_mode_debug_printmodeline(mode);

	}

}

/**

 * drm_helper_encoder_in_use - check if a given encoder is in use

 * @encoder: encoder to check

 *

 * LOCKING:

 * Caller must hold mode config lock.

 *

 * Walk @encoders's DRM device's mode_config and see if it's in use.

 *

 * RETURNS:

 * True if @encoder is part of the mode_config, false otherwise.

 */

bool drm_helper_encoder_in_use(struct drm_encoder *encoder)

{

	struct drm_connector *connector;

	struct drm_device *dev = encoder->dev;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head)

		if (connector->encoder == encoder)

			return true;

	return false;

}

EXPORT_SYMBOL(drm_helper_encoder_in_use);

/**

 * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config

 * @crtc: CRTC to check

 *

 * LOCKING:

 * Caller must hold mode config lock.

 *

 * Walk @crtc's DRM device's mode_config and see if it's in use.

 *

 * RETURNS:

 * True if @crtc is part of the mode_config, false otherwise.

 */

bool drm_helper_crtc_in_use(struct drm_crtc *crtc)

{

	struct drm_encoder *encoder;

	struct drm_device *dev = crtc->dev;

	/* FIXME: Locking around list access? */

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)

		if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))

			return true;

	return false;

}

EXPORT_SYMBOL(drm_helper_crtc_in_use);

/**

 * drm_disable_unused_functions - disable unused objects

 * @dev: DRM device

 *

 * LOCKING:

 * Caller must hold mode config lock.

 *

 * If an connector or CRTC isn't part of @dev's mode_config, it can be disabled

 * by calling its dpms function, which should power it off.

 */

void drm_helper_disable_unused_functions(struct drm_device *dev)

{

	struct drm_encoder *encoder;

	struct drm_encoder_helper_funcs *encoder_funcs;

	struct drm_crtc *crtc;

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		encoder_funcs = encoder->helper_private;

		if (!drm_helper_encoder_in_use(encoder))

			(*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);

	}

	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {

		struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;

		crtc->enabled = drm_helper_crtc_in_use(crtc);

		if (!crtc->enabled) {

			crtc_funcs->dpms(crtc, DRM_MODE_DPMS_OFF);

			crtc->fb = NULL;

		}

	}

}

EXPORT_SYMBOL(drm_helper_disable_unused_functions);

static struct drm_display_mode *drm_has_preferred_mode(struct drm_connector *connector, int width, int height)

{

	struct drm_display_mode *mode;

	list_for_each_entry(mode, &connector->modes, head) {

		if (drm_mode_width(mode) > width ||

		    drm_mode_height(mode) > height)

			continue;

		if (mode->type & DRM_MODE_TYPE_PREFERRED)

			return mode;

	}

	return NULL;

}

static bool drm_connector_enabled(struct drm_connector *connector, bool strict)

{

	bool enable;

	if (strict) {

		enable = connector->status == connector_status_connected;

	} else {

		enable = connector->status != connector_status_disconnected;

	}

	return enable;

}

static void drm_enable_connectors(struct drm_device *dev, bool *enabled)

{

	bool any_enabled = false;

	struct drm_connector *connector;

	int i = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		enabled[i] = drm_connector_enabled(connector, true);

		DRM_DEBUG("connector %d enabled? %s\n", connector->base.id,

			  enabled[i] ? "yes" : "no");

		any_enabled |= enabled[i];

		i++;

	}

	if (any_enabled)

		return;

	i = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		enabled[i] = drm_connector_enabled(connector, false);

		i++;

	}

}

static bool drm_target_preferred(struct drm_device *dev,

				 struct drm_display_mode **modes,

				 bool *enabled, int width, int height)

{

	struct drm_connector *connector;

	int i = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		if (enabled[i] == false) {

			i++;

			continue;

		}

		DRM_DEBUG("looking for preferred mode on connector %d\n",

			  connector->base.id);

		modes[i] = drm_has_preferred_mode(connector, width, height);

		/* No preferred modes, pick one off the list */

		if (!modes[i] && !list_empty(&connector->modes)) {

			list_for_each_entry(modes[i], &connector->modes, head)

				break;

		}

		DRM_DEBUG("found mode %s\n", modes[i] ? modes[i]->name :

			  "none");

		i++;

	}

	return true;

}

static int drm_pick_crtcs(struct drm_device *dev,

			  struct drm_crtc **best_crtcs,

			  struct drm_display_mode **modes,

			  int n, int width, int height)

{

	int c, o;

	struct drm_connector *connector;

	struct drm_connector_helper_funcs *connector_funcs;

	struct drm_encoder *encoder;

	struct drm_crtc *best_crtc;

	int my_score, best_score, score;

	struct drm_crtc **crtcs, *crtc;

	if (n == dev->mode_config.num_connector)

		return 0;

	c = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		if (c == n)

			break;

		c++;

	}

	best_crtcs[n] = NULL;

	best_crtc = NULL;

	best_score = drm_pick_crtcs(dev, best_crtcs, modes, n+1, width, height);

	if (modes[n] == NULL)

		return best_score;

	crtcs = kmalloc(dev->mode_config.num_connector *

			sizeof(struct drm_crtc *), GFP_KERNEL);

	if (!crtcs)

		return best_score;

	my_score = 1;

	if (connector->status == connector_status_connected)

		my_score++;

	if (drm_has_preferred_mode(connector, width, height))

		my_score++;

	connector_funcs = connector->helper_private;

	encoder = connector_funcs->best_encoder(connector);

	if (!encoder)

		goto out;

	connector->encoder = encoder;

	/* select a crtc for this connector and then attempt to configure

	   remaining connectors */

	c = 0;

	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {

		if ((connector->encoder->possible_crtcs & (1 << c)) == 0) {

			c++;

			continue;

		}

		for (o = 0; o < n; o++)

			if (best_crtcs[o] == crtc)

				break;

		if (o < n) {

			/* ignore cloning for now */

			c++;

			continue;

		}

		crtcs[n] = crtc;

		memcpy(crtcs, best_crtcs, n * sizeof(struct drm_crtc *));

		score = my_score + drm_pick_crtcs(dev, crtcs, modes, n + 1,

						  width, height);

		if (score > best_score) {

			best_crtc = crtc;

			best_score = score;

			memcpy(best_crtcs, crtcs,

			       dev->mode_config.num_connector *

			       sizeof(struct drm_crtc *));

		}

		c++;

	}

out:

	kfree(crtcs);

	return best_score;

}

static void drm_setup_crtcs(struct drm_device *dev)

{

	struct drm_crtc **crtcs;

	struct drm_display_mode **modes;

	struct drm_encoder *encoder;

	struct drm_connector *connector;

	bool *enabled;

	int width, height;

	int i, ret;

	DRM_DEBUG("\n");

	width = dev->mode_config.max_width;

	height = dev->mode_config.max_height;

	/* clean out all the encoder/crtc combos */

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		encoder->crtc = NULL;

	}

	crtcs = kcalloc(dev->mode_config.num_connector,

			sizeof(struct drm_crtc *), GFP_KERNEL);

	modes = kcalloc(dev->mode_config.num_connector,

			sizeof(struct drm_display_mode *), GFP_KERNEL);

	enabled = kcalloc(dev->mode_config.num_connector,

			  sizeof(bool), GFP_KERNEL);

	drm_enable_connectors(dev, enabled);

	ret = drm_target_preferred(dev, modes, enabled, width, height);

	if (!ret)

		DRM_ERROR("Unable to find initial modes\n");

	DRM_DEBUG("picking CRTCs for %dx%d config\n", width, height);

	drm_pick_crtcs(dev, crtcs, modes, 0, width, height);

	i = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		struct drm_display_mode *mode = modes[i];

		struct drm_crtc *crtc = crtcs[i];

		if (connector->encoder == NULL) {

			i++;

			continue;

		}

		if (mode && crtc) {

			DRM_DEBUG("desired mode %s set on crtc %d\n",

				  mode->name, crtc->base.id);

			crtc->desired_mode = mode;

			connector->encoder->crtc = crtc;

		} else

			connector->encoder->crtc = NULL;

		i++;

	}

	kfree(crtcs);

	kfree(modes);

	kfree(enabled);

}

/**

 * drm_encoder_crtc_ok - can a given crtc drive a given encoder?

 * @encoder: encoder to test

 * @crtc: crtc to test

 *

 * Return false if @encoder can't be driven by @crtc, true otherwise.

 */

static bool drm_encoder_crtc_ok(struct drm_encoder *encoder,

				struct drm_crtc *crtc)

{

	struct drm_device *dev;

	struct drm_crtc *tmp;

	int crtc_mask = 1;

	WARN(!crtc, "checking null crtc?");

	dev = crtc->dev;

	list_for_each_entry(tmp, &dev->mode_config.crtc_list, head) {

		if (tmp == crtc)

			break;

		crtc_mask <<= 1;

	}

	if (encoder->possible_crtcs & crtc_mask)

		return true;

	return false;

}

/*

 * Check the CRTC we're going to map each output to vs. its current

 * CRTC.  If they don't match, we have to disable the output and the CRTC

 * since the driver will have to re-route things.

 */

static void

drm_crtc_prepare_encoders(struct drm_device *dev)

{

	struct drm_encoder_helper_funcs *encoder_funcs;

	struct drm_encoder *encoder;

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		encoder_funcs = encoder->helper_private;

		/* Disable unused encoders */

		if (encoder->crtc == NULL)

			(*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);

		/* Disable encoders whose CRTC is about to change */

		if (encoder_funcs->get_crtc &&

		    encoder->crtc != (*encoder_funcs->get_crtc)(encoder))

			(*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);

	}

}

/**

 * drm_crtc_set_mode - set a mode

 * @crtc: CRTC to program

 * @mode: mode to use

 * @x: width of mode

 * @y: height of mode

 *

 * LOCKING:

 * Caller must hold mode config lock.

 *

 * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance

 * to fixup or reject the mode prior to trying to set it.

 *

 * RETURNS:

 * True if the mode was set successfully, or false otherwise.

 */

bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,

			      struct drm_display_mode *mode,

			      int x, int y,

			      struct drm_framebuffer *old_fb)

{

	struct drm_device *dev = crtc->dev;

	struct drm_display_mode *adjusted_mode, saved_mode;

	struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;

	struct drm_encoder_helper_funcs *encoder_funcs;

	int saved_x, saved_y;

	struct drm_encoder *encoder;

	bool ret = true;

	adjusted_mode = drm_mode_duplicate(dev, mode);

	crtc->enabled = drm_helper_crtc_in_use(crtc);

	if (!crtc->enabled)

		return true;

	saved_mode = crtc->mode;

	saved_x = crtc->x;

	saved_y = crtc->y;

	/* Update crtc values up front so the driver can rely on them for mode

	 * setting.

	 */

	crtc->mode = *mode;

	crtc->x = x;

	crtc->y = y;

	/* Pass our mode to the connectors and the CRTC to give them a chance to

	 * adjust it according to limitations or connector properties, and also

	 * a chance to reject the mode entirely.

	 */

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		if (encoder->crtc != crtc)

			continue;

		encoder_funcs = encoder->helper_private;

		if (!(ret = encoder_funcs->mode_fixup(encoder, mode,

						      adjusted_mode))) {

			goto done;

		}

	}

	if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {

		goto done;

	}

	/* Prepare the encoders and CRTCs before setting the mode. */

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		if (encoder->crtc != crtc)

			continue;

		encoder_funcs = encoder->helper_private;

		/* Disable the encoders as the first thing we do. */

		encoder_funcs->prepare(encoder);

	}

	drm_crtc_prepare_encoders(dev);

	crtc_funcs->prepare(crtc);

	/* Set up the DPLL and any encoders state that needs to adjust or depend

	 * on the DPLL.

	 */

	ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);

	if (!ret)

	    goto done;

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		if (encoder->crtc != crtc)

			continue;

		DRM_INFO("%s: set mode %s %x\n", drm_get_encoder_name(encoder),

			 mode->name, mode->base.id);

		encoder_funcs = encoder->helper_private;

		encoder_funcs->mode_set(encoder, mode, adjusted_mode);

	}

	/* Now enable the clocks, plane, pipe, and connectors that we set up. */

	crtc_funcs->commit(crtc);

	list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {

		if (encoder->crtc != crtc)

			continue;

		encoder_funcs = encoder->helper_private;

		encoder_funcs->commit(encoder);

	}

	/* XXX free adjustedmode */

	drm_mode_destroy(dev, adjusted_mode);

	/* FIXME: add subpixel order */

done:

	if (!ret) {

		crtc->mode = saved_mode;

		crtc->x = saved_x;

		crtc->y = saved_y;

	}

	return ret;

}

EXPORT_SYMBOL(drm_crtc_helper_set_mode);

/**

 * drm_crtc_helper_set_config - set a new config from userspace

 * @crtc: CRTC to setup

 * @crtc_info: user provided configuration

 * @new_mode: new mode to set

 * @connector_set: set of connectors for the new config

 * @fb: new framebuffer

 *

 * LOCKING:

 * Caller must hold mode config lock.

 *

 * Setup a new configuration, provided by the user in @crtc_info, and enable

 * it.

 *

 * RETURNS:

 * Zero. (FIXME)

 */

int drm_crtc_helper_set_config(struct drm_mode_set *set)

{

	struct drm_device *dev;

	struct drm_crtc **save_crtcs, *new_crtc;

	struct drm_encoder **save_encoders, *new_encoder;

	struct drm_framebuffer *old_fb = NULL;

	bool save_enabled;

	bool mode_changed = false;

	bool fb_changed = false;

	struct drm_connector *connector;

	int count = 0, ro, fail = 0;

	struct drm_crtc_helper_funcs *crtc_funcs;

	int ret = 0;

	DRM_DEBUG("\n");

	if (!set)

		return -EINVAL;

	if (!set->crtc)

		return -EINVAL;

	if (!set->crtc->helper_private)

		return -EINVAL;

	crtc_funcs = set->crtc->helper_private;

	DRM_DEBUG("crtc: %p %d fb: %p connectors: %p num_connectors: %d (x, y) (%i, %i)\n",

		  set->crtc, set->crtc->base.id, set->fb, set->connectors,

		  (int)set->num_connectors, set->x, set->y);

	dev = set->crtc->dev;

	/* save previous config */

	save_enabled = set->crtc->enabled;

	/*

	 * We do mode_config.num_connectors here since we'll look at the

	 * CRTC and encoder associated with each connector later.

	 */

	save_crtcs = kzalloc(dev->mode_config.num_connector *

			     sizeof(struct drm_crtc *), GFP_KERNEL);

	if (!save_crtcs)

		return -ENOMEM;

	save_encoders = kzalloc(dev->mode_config.num_connector *

				sizeof(struct drm_encoders *), GFP_KERNEL);

	if (!save_encoders) {

		kfree(save_crtcs);

		return -ENOMEM;

	}

	/* We should be able to check here if the fb has the same properties

	 * and then just flip_or_move it */

	if (set->crtc->fb != set->fb) {

		/* If we have no fb then treat it as a full mode set */

		if (set->crtc->fb == NULL) {

			DRM_DEBUG("crtc has no fb, full mode set\n");

			mode_changed = true;

		} else if ((set->fb->bits_per_pixel !=

			 set->crtc->fb->bits_per_pixel) ||

			 set->fb->depth != set->crtc->fb->depth)

			fb_changed = true;

		else

			fb_changed = true;

	}

	if (set->x != set->crtc->x || set->y != set->crtc->y)

		fb_changed = true;

	if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {

		DRM_DEBUG("modes are different, full mode set\n");

		drm_mode_debug_printmodeline(&set->crtc->mode);

		drm_mode_debug_printmodeline(set->mode);

		mode_changed = true;

	}

	/* a) traverse passed in connector list and get encoders for them */

	count = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		struct drm_connector_helper_funcs *connector_funcs =

			connector->helper_private;

		save_encoders[count++] = connector->encoder;

		new_encoder = connector->encoder;

		for (ro = 0; ro < set->num_connectors; ro++) {

			if (set->connectors[ro] == connector) {

				new_encoder = connector_funcs->best_encoder(connector);

				/* if we can't get an encoder for a connector

				   we are setting now - then fail */

				if (new_encoder == NULL)

					/* don't break so fail path works correct */

					fail = 1;

				break;

			}

		}

		if (new_encoder != connector->encoder) {

			DRM_DEBUG("encoder changed, full mode switch\n");

			mode_changed = true;

			connector->encoder = new_encoder;

		}

	}

	if (fail) {

		ret = -EINVAL;

		goto fail_no_encoder;

	}

	count = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		if (!connector->encoder)

			continue;

		save_crtcs[count++] = connector->encoder->crtc;

		if (connector->encoder->crtc == set->crtc)

			new_crtc = NULL;

		else

			new_crtc = connector->encoder->crtc;

		for (ro = 0; ro < set->num_connectors; ro++) {

			if (set->connectors[ro] == connector)

				new_crtc = set->crtc;

		}

		/* Make sure the new CRTC will work with the encoder */

		if (new_crtc &&

		    !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {

			ret = -EINVAL;

			goto fail_set_mode;

		}

		if (new_crtc != connector->encoder->crtc) {

			DRM_DEBUG("crtc changed, full mode switch\n");

			mode_changed = true;

			connector->encoder->crtc = new_crtc;

		}

		DRM_DEBUG("setting connector %d crtc to %p\n",

			  connector->base.id, new_crtc);

	}

	/* mode_set_base is not a required function */

	if (fb_changed && !crtc_funcs->mode_set_base)

		mode_changed = true;

	if (mode_changed) {

		old_fb = set->crtc->fb;

		set->crtc->fb = set->fb;

		set->crtc->enabled = (set->mode != NULL);

		if (set->mode != NULL) {

			DRM_DEBUG("attempting to set mode from userspace\n");

			drm_mode_debug_printmodeline(set->mode);

			if (!drm_crtc_helper_set_mode(set->crtc, set->mode,

						      set->x, set->y,

						      old_fb)) {

				DRM_ERROR("failed to set mode on crtc %p\n",

					  set->crtc);

				ret = -EINVAL;

				goto fail_set_mode;

			}

			/* TODO are these needed? */

			set->crtc->desired_x = set->x;

			set->crtc->desired_y = set->y;

			set->crtc->desired_mode = set->mode;

		}

		drm_helper_disable_unused_functions(dev);

	} else if (fb_changed) {

		old_fb = set->crtc->fb;

		if (set->crtc->fb != set->fb)

			set->crtc->fb = set->fb;

		ret = crtc_funcs->mode_set_base(set->crtc,

						set->x, set->y, old_fb);

		if (ret != 0)

		    goto fail_set_mode;

	}

	kfree(save_encoders);

	kfree(save_crtcs);

	return 0;

fail_set_mode:

	set->crtc->enabled = save_enabled;

	set->crtc->fb = old_fb;

	count = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		if (!connector->encoder)

			continue;

		connector->encoder->crtc = save_crtcs[count++];

	}

fail_no_encoder:

	kfree(save_crtcs);

	count = 0;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {

		connector->encoder = save_encoders[count++];

	}

	kfree(save_encoders);

	return ret;

}

EXPORT_SYMBOL(drm_crtc_helper_set_config);

bool drm_helper_plugged_event(struct drm_device *dev)

{

	DRM_DEBUG("\n");

	drm_helper_probe_connector_modes(dev, dev->mode_config.max_width,

					 dev->mode_config.max_height);

	drm_setup_crtcs(dev);

	/* alert the driver fb layer */

	dev->mode_config.funcs->fb_changed(dev);

	/* FIXME: send hotplug event */

	return true;

}

/**

 * drm_initial_config - setup a sane initial connector configuration

 * @dev: DRM device

 *

 * LOCKING:

 * Called at init time, must take mode config lock.

 *

 * Scan the CRTCs and connectors and try to put together an initial setup.

 * At the moment, this is a cloned configuration across all heads with

 * a new framebuffer object as the backing store.

 *

 * RETURNS:

 * Zero if everything went ok, nonzero otherwise.

 */

bool drm_helper_initial_config(struct drm_device *dev)

{

	struct drm_connector *connector;

	int count = 0;

	count = drm_helper_probe_connector_modes(dev,

						 dev->mode_config.max_width,

						 dev->mode_config.max_height);

	/*

	 * None of the available connectors had any modes, so add some

	 * and try to light them up anyway

	 */

	if (!count) {

		DRM_ERROR("connectors have no modes, using standard modes\n");

		list_for_each_entry(connector,

				    &dev->mode_config.connector_list,

				    head)

			drm_helper_add_std_modes(dev, connector);

	}

	drm_setup_crtcs(dev);

	/* alert the driver fb layer */

	dev->mode_config.funcs->fb_changed(dev);

	return 0;

}

EXPORT_SYMBOL(drm_helper_initial_config);

static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)

{

	int dpms = DRM_MODE_DPMS_OFF;

	struct drm_connector *connector;

	struct drm_device *dev = encoder->dev;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head)

		if (connector->encoder == encoder)

			if (connector->dpms < dpms)

				dpms = connector->dpms;

	return dpms;

}

static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)

{

	int dpms = DRM_MODE_DPMS_OFF;

	struct drm_connector *connector;

	struct drm_device *dev = crtc->dev;

	list_for_each_entry(connector, &dev->mode_config.connector_list, head)

		if (connector->encoder && connector->encoder->crtc == crtc)

			if (connector->dpms < dpms)

				dpms = connector->dpms;

	return dpms;

}

/**

 * drm_helper_connector_dpms

 * @connector affected connector

 * @mode DPMS mode

 *

 * Calls the low-level connector DPMS function, then

 * calls appropriate encoder and crtc DPMS functions as well

 */

void drm_helper_connector_dpms(struct drm_connector *connector, int mode)

{

	struct drm_encoder *encoder = connector->encoder;

	struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;

	int old_dpms;

	if (mode == connector->dpms)

		return;

	old_dpms = connector->dpms;

	connector->dpms = mode;

	/* from off to on, do crtc then encoder */

	if (mode < old_dpms) {

		if (crtc) {

			struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;

			if (crtc_funcs->dpms)

				(*crtc_funcs->dpms) (crtc,

						     drm_helper_choose_crtc_dpms(crtc));

		}

		if (encoder) {

			struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;

			if (encoder_funcs->dpms)

				(*encoder_funcs->dpms) (encoder,

							drm_helper_choose_encoder_dpms(encoder));

		}

	}

	/* from on to off, do encoder then crtc */

	if (mode > old_dpms) {

		if (encoder) {

			struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;

			if (encoder_funcs->dpms)

				(*encoder_funcs->dpms) (encoder,

							drm_helper_choose_encoder_dpms(encoder));

		}

		if (crtc) {

			struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;

			if (crtc_funcs->dpms)

				(*crtc_funcs->dpms) (crtc,

						     drm_helper_choose_crtc_dpms(crtc));

		}

	}

	return;

}

EXPORT_SYMBOL(drm_helper_connector_dpms);

/**

 * drm_hotplug_stage_two

 * @dev DRM device

 * @connector hotpluged connector

 *

 * LOCKING.

 * Caller must hold mode config lock, function might grab struct lock.

 *

 * Stage two of a hotplug.

 *

 * RETURNS:

 * Zero on success, errno on failure.

 */

int drm_helper_hotplug_stage_two(struct drm_device *dev)

{

	drm_helper_plugged_event(dev);

	return 0;

}

EXPORT_SYMBOL(drm_helper_hotplug_stage_two);

int drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,

				   struct drm_mode_fb_cmd *mode_cmd)

{

	fb->width = mode_cmd->width;

	fb->height = mode_cmd->height;

	fb->pitch = mode_cmd->pitch;

	fb->bits_per_pixel = mode_cmd->bpp;

	fb->depth = mode_cmd->depth;

	return 0;

}

EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);

int drm_helper_resume_force_mode(struct drm_device *dev)

{

	struct drm_crtc *crtc;

	int ret;

	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {

		if (!crtc->enabled)

			continue;

		ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,

					       crtc->x, crtc->y, crtc->fb);

		if (ret == false)

			DRM_ERROR("failed to set mode on crtc %p\n", crtc);

	}

	return 0;

}

EXPORT_SYMBOL(drm_helper_resume_force_mode);