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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"

#include "drm_fb_helper.h"

static bool drm_kms_helper_poll = true;

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_single_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_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,

			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;

	if (connector->force) {

		if (connector->force == DRM_FORCE_ON)

			connector->status = connector_status_connected;

		else

			connector->status = connector_status_disconnected;

		if (connector->funcs->force)

			connector->funcs->force(connector);

	} else {

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

//		drm_kms_helper_poll_enable(dev);

	}

	if (connector->status == connector_status_disconnected) {

		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",

			connector->base.id, drm_get_connector_name(connector));

		drm_mode_connector_update_edid_property(connector, NULL);

		goto prune;

	}

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

	if (count == 0 && connector->status == connector_status_connected)

		count = drm_add_modes_noedid(connector, 1024, 768);

	if (count == 0)

		goto prune;

	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);

	}

prune:

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

	if (list_empty(&connector->modes))

		return 0;

	drm_mode_sort(&connector->modes);

	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,

				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);

/**

 * 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);

static void

drm_encoder_disable(struct drm_encoder *encoder)

{

	struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;

	if (encoder_funcs->disable)

		(*encoder_funcs->disable)(encoder);

	else

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

}

/**

 * drm_helper_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_connector *connector;

	struct drm_crtc *crtc;

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

		if (!connector->encoder)

			continue;

		if (connector->status == connector_status_disconnected)

			connector->encoder = NULL;

	}

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

		if (!drm_helper_encoder_in_use(encoder)) {

			drm_encoder_disable(encoder);

			/* disconnector encoder from any connector */

			encoder->crtc = NULL;

		}

	}

	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) {

			if (crtc_funcs->disable)

				(*crtc_funcs->disable)(crtc);

			else

				(*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);

			crtc->fb = NULL;

		}

	}

}

EXPORT_SYMBOL(drm_helper_disable_unused_functions);

/**

 * 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?\n");

	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)

			drm_encoder_disable(encoder);

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

		if (encoder_funcs->get_crtc &&

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

			drm_encoder_disable(encoder);

	}

}

/**

 * 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, saved_hwmode;

	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;

	crtc->enabled = drm_helper_crtc_in_use(crtc);

	if (!crtc->enabled)

		return true;

	adjusted_mode = drm_mode_duplicate(dev, mode);

	saved_hwmode = crtc->hwmode;

	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;

	}

	DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);

	/* 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_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",

			encoder->base.id, drm_get_encoder_name(encoder),

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

		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);

	}

	/* Store real post-adjustment hardware mode. */

	crtc->hwmode = *adjusted_mode;

	/* Calculate and store various constants which

	 * are later needed by vblank and swap-completion

	 * timestamping. They are derived from true hwmode.

	 */

	drm_calc_timestamping_constants(crtc);

	/* FIXME: add subpixel order */

done:

	drm_mode_destroy(dev, adjusted_mode);

	if (!ret) {

		crtc->hwmode = saved_hwmode;

		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, *crtc;

	struct drm_encoder *save_encoders, *new_encoder, *encoder;

	struct drm_framebuffer *old_fb = NULL;

	bool mode_changed = false; /* if true do a full mode set */

	bool fb_changed = false; /* if true and !mode_changed just do a flip */

	struct drm_connector *save_connectors, *connector;

	int count = 0, ro, fail = 0;

	struct drm_crtc_helper_funcs *crtc_funcs;

	int ret = 0;

	int i;

	DRM_DEBUG_KMS("\n");

	if (!set)

		return -EINVAL;

	if (!set->crtc)

		return -EINVAL;

	if (!set->crtc->helper_private)

		return -EINVAL;

	crtc_funcs = set->crtc->helper_private;

	if (!set->mode)

		set->fb = NULL;

	if (set->fb) {

		DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",

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

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

	} else {

		DRM_DEBUG_KMS("[CRTC:%d] [NOFB]\n", set->crtc->base.id);

		set->mode = NULL;

		set->num_connectors = 0;

	}

	dev = set->crtc->dev;

	/* Allocate space for the backup of all (non-pointer) crtc, encoder and

	 * connector data. */

	save_crtcs = kzalloc(dev->mode_config.num_crtc *

			     sizeof(struct drm_crtc), GFP_KERNEL);

	if (!save_crtcs)

		return -ENOMEM;

	save_encoders = kzalloc(dev->mode_config.num_encoder *

				sizeof(struct drm_encoder), GFP_KERNEL);

	if (!save_encoders) {

		kfree(save_crtcs);

		return -ENOMEM;

	}

	save_connectors = kzalloc(dev->mode_config.num_connector *

				sizeof(struct drm_connector), GFP_KERNEL);

	if (!save_connectors) {

		kfree(save_crtcs);

		kfree(save_encoders);

		return -ENOMEM;

	}

	/* Copy data. Note that driver private data is not affected.

	 * Should anything bad happen only the expected state is

	 * restored, not the drivers personal bookkeeping.

	 */

	count = 0;

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

		save_crtcs[count++] = *crtc;

	}

	count = 0;

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

		save_encoders[count++] = *encoder;

	}

	count = 0;

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

		save_connectors[count++] = *connector;

	}

	/* 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_KMS("crtc has no fb, full mode set\n");

			mode_changed = true;

		} else if (set->fb == NULL) {

			mode_changed = true;

		} else if (set->fb->depth != set->crtc->fb->depth) {

			mode_changed = true;

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

			   set->crtc->fb->bits_per_pixel) {

			mode_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_KMS("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;

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

			mode_changed = true;

			/* If the encoder is reused for another connector, then

			 * the appropriate crtc will be set later.

			 */

			if (connector->encoder)

				connector->encoder->crtc = NULL;

			connector->encoder = new_encoder;

		}

	}

	if (fail) {

		ret = -EINVAL;

		goto fail;

	}

	count = 0;

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

		if (!connector->encoder)

			continue;

		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;

		}

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

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

			mode_changed = true;

			connector->encoder->crtc = new_crtc;

		}

		if (new_crtc) {

			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d]\n",

				connector->base.id, drm_get_connector_name(connector),

				new_crtc->base.id);

		} else {

			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",

				connector->base.id, drm_get_connector_name(connector));

		}

	}

	/* mode_set_base is not a required function */

	if (fb_changed && !crtc_funcs->mode_set_base)

		mode_changed = true;

	if (mode_changed) {

		set->crtc->enabled = drm_helper_crtc_in_use(set->crtc);

		if (set->crtc->enabled) {

			DRM_DEBUG_KMS("attempting to set mode from"

					" userspace\n");

			drm_mode_debug_printmodeline(set->mode);

			old_fb = set->crtc->fb;

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

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

						      set->x, set->y,

						      old_fb)) {

				DRM_ERROR("failed to set mode on [CRTC:%d]\n",

					  set->crtc->base.id);

				set->crtc->fb = old_fb;

				ret = -EINVAL;

				goto fail;

			}

			DRM_DEBUG_KMS("Setting connector DPMS state to on\n");

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

				DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,

					      drm_get_connector_name(set->connectors[i]));

				set->connectors[i]->dpms = DRM_MODE_DPMS_ON;

			}

		}

		drm_helper_disable_unused_functions(dev);

	} else if (fb_changed) {

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

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

		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) {

			set->crtc->fb = old_fb;

			goto fail;

	}

	}

	kfree(save_connectors);

	kfree(save_encoders);

	kfree(save_crtcs);

	return 0;

fail:

	/* Restore all previous data. */

	count = 0;

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

		*crtc = save_crtcs[count++];

	}

	count = 0;

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

		*encoder = save_encoders[count++];

	}

	count = 0;

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

		*connector = save_connectors[count++];

	}

	kfree(save_connectors);

	kfree(save_encoders);

	kfree(save_crtcs);

	return ret;

}

EXPORT_SYMBOL(drm_crtc_helper_set_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);

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;

	struct drm_encoder *encoder;

	struct drm_encoder_helper_funcs *encoder_funcs;

	struct drm_crtc_helper_funcs *crtc_funcs;

	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);

		/* Turn off outputs that were already powered off */

		if (drm_helper_choose_crtc_dpms(crtc)) {

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

				if(encoder->crtc != crtc)

					continue;

				encoder_funcs = encoder->helper_private;

				if (encoder_funcs->dpms)

					(*encoder_funcs->dpms) (encoder,

								drm_helper_choose_encoder_dpms(encoder));

			}

				crtc_funcs = crtc->helper_private;

				if (crtc_funcs->dpms)

					(*crtc_funcs->dpms) (crtc,

							     drm_helper_choose_crtc_dpms(crtc));

			}

		}

	/* disable the unused connectors while restoring the modesetting */

	drm_helper_disable_unused_functions(dev);

	return 0;

}

EXPORT_SYMBOL(drm_helper_resume_force_mode);

#if 0

#define DRM_OUTPUT_POLL_PERIOD (10*HZ)

static void output_poll_execute(struct work_struct *work)

{

	struct delayed_work *delayed_work = to_delayed_work(work);

	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);

	struct drm_connector *connector;

	enum drm_connector_status old_status;

	bool repoll = false, changed = false;

	if (!drm_kms_helper_poll)

		return;

	mutex_lock(&dev->mode_config.mutex);

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

		/* if this is HPD or polled don't check it -

		   TV out for instance */

		if (!connector->polled)

			continue;

		else if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT))

			repoll = true;

		old_status = connector->status;

		/* if we are connected and don't want to poll for disconnect

		   skip it */

		if (old_status == connector_status_connected &&

		    !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT) &&

		    !(connector->polled & DRM_CONNECTOR_POLL_HPD))

			continue;

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

		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %d to %d\n",

			      connector->base.id,

			      drm_get_connector_name(connector),

			      old_status, connector->status);

		if (old_status != connector->status)

			changed = true;

	}

	mutex_unlock(&dev->mode_config.mutex);

	if (changed) {

		/* send a uevent + call fbdev */

		drm_sysfs_hotplug_event(dev);

		if (dev->mode_config.funcs->output_poll_changed)

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

	}

	if (repoll)

		queue_delayed_work(system_nrt_wq, delayed_work, DRM_OUTPUT_POLL_PERIOD);

}

void drm_kms_helper_poll_disable(struct drm_device *dev)

{

	if (!dev->mode_config.poll_enabled)

		return;

	cancel_delayed_work_sync(&dev->mode_config.output_poll_work);

}

EXPORT_SYMBOL(drm_kms_helper_poll_disable);

void drm_kms_helper_poll_enable(struct drm_device *dev)

{

	bool poll = false;

	struct drm_connector *connector;

	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)

		return;

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

		if (connector->polled)

			poll = true;

	}

	if (poll)

		queue_delayed_work(system_nrt_wq, &dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);

}

EXPORT_SYMBOL(drm_kms_helper_poll_enable);

void drm_kms_helper_poll_init(struct drm_device *dev)

{

	INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);

	dev->mode_config.poll_enabled = true;

	drm_kms_helper_poll_enable(dev);

}

EXPORT_SYMBOL(drm_kms_helper_poll_init);

void drm_kms_helper_poll_fini(struct drm_device *dev)

{

	drm_kms_helper_poll_disable(dev);

}

EXPORT_SYMBOL(drm_kms_helper_poll_fini);

void drm_helper_hpd_irq_event(struct drm_device *dev)

{

	if (!dev->mode_config.poll_enabled)

		return;

	/* kill timer and schedule immediate execution, this doesn't block */

	cancel_delayed_work(&dev->mode_config.output_poll_work);

	if (drm_kms_helper_poll)

	queue_delayed_work(system_nrt_wq, &dev->mode_config.output_poll_work, 0);

}

EXPORT_SYMBOL(drm_helper_hpd_irq_event);

#endif