drivers/gpu/drm/i915/intel_lvds.c - maze/linux - Git at Google

 /*
  * Copyright © 2006-2007 Intel Corporation
  * Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice (including the next
  * paragraph) shall be included in all copies or substantial portions of the
  * Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  *
  * Authors:
  *	Eric Anholt <eric@anholt.net>
  *      Dave Airlie <airlied@linux.ie>
  *      Jesse Barnes <jesse.barnes@intel.com>
  */

 #include <linux/i2c.h>
 #include "drmP.h"
 #include "drm.h"
 #include "drm_crtc.h"
 #include "drm_edid.h"
 #include "intel_drv.h"
 #include "i915_drm.h"
 #include "i915_drv.h"

 /**
  * Sets the backlight level.
  *
  * \param level backlight level, from 0 to intel_lvds_get_max_backlight().
  */
 static void intel_lvds_set_backlight(struct drm_device *dev, int level)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 blc_pwm_ctl;

 	blc_pwm_ctl = I915_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
 	I915_WRITE(BLC_PWM_CTL, (blc_pwm_ctl |
 				 (level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
 }

 /**
  * Returns the maximum level of the backlight duty cycle field.
  */
 static u32 intel_lvds_get_max_backlight(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	return ((I915_READ(BLC_PWM_CTL) & BACKLIGHT_MODULATION_FREQ_MASK) >>
 		BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
 }

 /**
  * Sets the power state for the panel.
  */
 static void intel_lvds_set_power(struct drm_device *dev, bool on)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 pp_status;

 	if (on) {
 		I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) |
 			   POWER_TARGET_ON);
 		do {
 			pp_status = I915_READ(PP_STATUS);
 		} while ((pp_status & PP_ON) == 0);

 		intel_lvds_set_backlight(dev, dev_priv->backlight_duty_cycle);
 	} else {
 		intel_lvds_set_backlight(dev, 0);

 		I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) &
 			   ~POWER_TARGET_ON);
 		do {
 			pp_status = I915_READ(PP_STATUS);
 		} while (pp_status & PP_ON);
 	}
 }

 static void intel_lvds_dpms(struct drm_encoder *encoder, int mode)
 {
 	struct drm_device *dev = encoder->dev;

 	if (mode == DRM_MODE_DPMS_ON)
 		intel_lvds_set_power(dev, true);
 	else
 		intel_lvds_set_power(dev, false);

 	/* XXX: We never power down the LVDS pairs. */
 }

 static void intel_lvds_save(struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	dev_priv->savePP_ON = I915_READ(PP_ON_DELAYS);
 	dev_priv->savePP_OFF = I915_READ(PP_OFF_DELAYS);
 	dev_priv->savePP_CONTROL = I915_READ(PP_CONTROL);
 	dev_priv->savePP_DIVISOR = I915_READ(PP_DIVISOR);
 	dev_priv->saveBLC_PWM_CTL = I915_READ(BLC_PWM_CTL);
 	dev_priv->backlight_duty_cycle = (dev_priv->saveBLC_PWM_CTL &
 				       BACKLIGHT_DUTY_CYCLE_MASK);

 	/*
 	 * If the light is off at server startup, just make it full brightness
 	 */
 	if (dev_priv->backlight_duty_cycle == 0)
 		dev_priv->backlight_duty_cycle =
 			intel_lvds_get_max_backlight(dev);
 }

 static void intel_lvds_restore(struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	I915_WRITE(BLC_PWM_CTL, dev_priv->saveBLC_PWM_CTL);
 	I915_WRITE(PP_ON_DELAYS, dev_priv->savePP_ON);
 	I915_WRITE(PP_OFF_DELAYS, dev_priv->savePP_OFF);
 	I915_WRITE(PP_DIVISOR, dev_priv->savePP_DIVISOR);
 	I915_WRITE(PP_CONTROL, dev_priv->savePP_CONTROL);
 	if (dev_priv->savePP_CONTROL & POWER_TARGET_ON)
 		intel_lvds_set_power(dev, true);
 	else
 		intel_lvds_set_power(dev, false);
 }

 static int intel_lvds_mode_valid(struct drm_connector *connector,
 				 struct drm_display_mode *mode)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct drm_display_mode *fixed_mode = dev_priv->panel_fixed_mode;

 	if (fixed_mode)	{
 		if (mode->hdisplay > fixed_mode->hdisplay)
 			return MODE_PANEL;
 		if (mode->vdisplay > fixed_mode->vdisplay)
 			return MODE_PANEL;
 	}

 	return MODE_OK;
 }

 static bool intel_lvds_mode_fixup(struct drm_encoder *encoder,
 				  struct drm_display_mode *mode,
 				  struct drm_display_mode *adjusted_mode)
 {
 	struct drm_device *dev = encoder->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->crtc);
 	struct drm_encoder *tmp_encoder;

 	/* Should never happen!! */
 	if (!IS_I965G(dev) && intel_crtc->pipe == 0) {
 		printk(KERN_ERR "Can't support LVDS on pipe A\n");
 		return false;
 	}

 	/* Should never happen!! */
 	list_for_each_entry(tmp_encoder, &dev->mode_config.encoder_list, head) {
 		if (tmp_encoder != encoder && tmp_encoder->crtc == encoder->crtc) {
 			printk(KERN_ERR "Can't enable LVDS and another "
 			       "encoder on the same pipe\n");
 			return false;
 		}
 	}

 	/*
 	 * If we have timings from the BIOS for the panel, put them in
 	 * to the adjusted mode.  The CRTC will be set up for this mode,
 	 * with the panel scaling set up to source from the H/VDisplay
 	 * of the original mode.
 	 */
 	if (dev_priv->panel_fixed_mode != NULL) {
 		adjusted_mode->hdisplay = dev_priv->panel_fixed_mode->hdisplay;
 		adjusted_mode->hsync_start =
 			dev_priv->panel_fixed_mode->hsync_start;
 		adjusted_mode->hsync_end =
 			dev_priv->panel_fixed_mode->hsync_end;
 		adjusted_mode->htotal = dev_priv->panel_fixed_mode->htotal;
 		adjusted_mode->vdisplay = dev_priv->panel_fixed_mode->vdisplay;
 		adjusted_mode->vsync_start =
 			dev_priv->panel_fixed_mode->vsync_start;
 		adjusted_mode->vsync_end =
 			dev_priv->panel_fixed_mode->vsync_end;
 		adjusted_mode->vtotal = dev_priv->panel_fixed_mode->vtotal;
 		adjusted_mode->clock = dev_priv->panel_fixed_mode->clock;
 		drm_mode_set_crtcinfo(adjusted_mode, CRTC_INTERLACE_HALVE_V);
 	}

 	/*
 	 * XXX: It would be nice to support lower refresh rates on the
 	 * panels to reduce power consumption, and perhaps match the
 	 * user's requested refresh rate.
 	 */

 	return true;
 }

 static void intel_lvds_prepare(struct drm_encoder *encoder)
 {
 	struct drm_device *dev = encoder->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	dev_priv->saveBLC_PWM_CTL = I915_READ(BLC_PWM_CTL);
 	dev_priv->backlight_duty_cycle = (dev_priv->saveBLC_PWM_CTL &
 				       BACKLIGHT_DUTY_CYCLE_MASK);

 	intel_lvds_set_power(dev, false);
 }

 static void intel_lvds_commit( struct drm_encoder *encoder)
 {
 	struct drm_device *dev = encoder->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	if (dev_priv->backlight_duty_cycle == 0)
 		dev_priv->backlight_duty_cycle =
 			intel_lvds_get_max_backlight(dev);

 	intel_lvds_set_power(dev, true);
 }

 static void intel_lvds_mode_set(struct drm_encoder *encoder,
 				struct drm_display_mode *mode,
 				struct drm_display_mode *adjusted_mode)
 {
 	struct drm_device *dev = encoder->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->crtc);
 	u32 pfit_control;

 	/*
 	 * The LVDS pin pair will already have been turned on in the
 	 * intel_crtc_mode_set since it has a large impact on the DPLL
 	 * settings.
 	 */

 	/*
 	 * Enable automatic panel scaling so that non-native modes fill the
 	 * screen.  Should be enabled before the pipe is enabled, according to
 	 * register description and PRM.
 	 */
 	if (mode->hdisplay != adjusted_mode->hdisplay ||
 	    mode->vdisplay != adjusted_mode->vdisplay)
 		pfit_control = (PFIT_ENABLE | VERT_AUTO_SCALE |
 				HORIZ_AUTO_SCALE | VERT_INTERP_BILINEAR |
 				HORIZ_INTERP_BILINEAR);
 	else
 		pfit_control = 0;

 	if (!IS_I965G(dev)) {
 		if (dev_priv->panel_wants_dither)
 			pfit_control |= PANEL_8TO6_DITHER_ENABLE;
 	}
 	else
 		pfit_control |= intel_crtc->pipe << PFIT_PIPE_SHIFT;

 	I915_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 intel_lvds_detect(struct drm_connector *connector)
 {
 	return connector_status_connected;
 }

 /**
  * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
  */
 static int intel_lvds_get_modes(struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
 	struct intel_output *intel_output = to_intel_output(connector);
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	int ret = 0;

 	ret = intel_ddc_get_modes(intel_output);

 	if (ret)
 		return ret;

 	/* Didn't get an EDID, so
 	 * Set wide sync ranges so we get all modes
 	 * handed to valid_mode for checking
 	 */
 	connector->display_info.min_vfreq = 0;
 	connector->display_info.max_vfreq = 200;
 	connector->display_info.min_hfreq = 0;
 	connector->display_info.max_hfreq = 200;

 	if (dev_priv->panel_fixed_mode != NULL) {
 		struct drm_display_mode *mode;

 		mutex_lock(&dev->mode_config.mutex);
 		mode = drm_mode_duplicate(dev, dev_priv->panel_fixed_mode);
 		drm_mode_probed_add(connector, mode);
 		mutex_unlock(&dev->mode_config.mutex);

 		return 1;
 	}

 	return 0;
 }

 /**
  * intel_lvds_destroy - unregister and free LVDS structures
  * @connector: connector to free
  *
  * Unregister the DDC bus for this connector then free the driver private
  * structure.
  */
 static void intel_lvds_destroy(struct drm_connector *connector)
 {
 	struct intel_output *intel_output = to_intel_output(connector);

 	if (intel_output->ddc_bus)
 		intel_i2c_destroy(intel_output->ddc_bus);
 	drm_sysfs_connector_remove(connector);
 	drm_connector_cleanup(connector);
 	kfree(connector);
 }

 static int intel_lvds_set_property(struct drm_connector *connector,
 				   struct drm_property *property,
 				   uint64_t value)
 {
 	struct drm_device *dev = connector->dev;

 	if (property == dev->mode_config.dpms_property && connector->encoder)
 		intel_lvds_dpms(connector->encoder, (uint32_t)(value & 0xf));

 	return 0;
 }

 static const struct drm_encoder_helper_funcs intel_lvds_helper_funcs = {
 	.dpms = intel_lvds_dpms,
 	.mode_fixup = intel_lvds_mode_fixup,
 	.prepare = intel_lvds_prepare,
 	.mode_set = intel_lvds_mode_set,
 	.commit = intel_lvds_commit,
 };

 static const struct drm_connector_helper_funcs intel_lvds_connector_helper_funcs = {
 	.get_modes = intel_lvds_get_modes,
 	.mode_valid = intel_lvds_mode_valid,
 	.best_encoder = intel_best_encoder,
 };

 static const struct drm_connector_funcs intel_lvds_connector_funcs = {
 	.save = intel_lvds_save,
 	.restore = intel_lvds_restore,
 	.detect = intel_lvds_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.set_property = intel_lvds_set_property,
 	.destroy = intel_lvds_destroy,
 };


 static void intel_lvds_enc_destroy(struct drm_encoder *encoder)
 {
 	drm_encoder_cleanup(encoder);
 }

 static const struct drm_encoder_funcs intel_lvds_enc_funcs = {
 	.destroy = intel_lvds_enc_destroy,
 };


 /**
  * intel_lvds_init - setup LVDS connectors on this device
  * @dev: drm device
  *
  * Create the connector, register the LVDS DDC bus, and try to figure out what
  * modes we can display on the LVDS panel (if present).
  */
 void intel_lvds_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_output *intel_output;
 	struct drm_connector *connector;
 	struct drm_encoder *encoder;
 	struct drm_display_mode *scan; /* *modes, *bios_mode; */
 	struct drm_crtc *crtc;
 	u32 lvds;
 	int pipe;

 	intel_output = kzalloc(sizeof(struct intel_output), GFP_KERNEL);
 	if (!intel_output) {
 		return;
 	}

 	connector = &intel_output->base;
 	encoder = &intel_output->enc;
 	drm_connector_init(dev, &intel_output->base, &intel_lvds_connector_funcs,
 			   DRM_MODE_CONNECTOR_LVDS);

 	drm_encoder_init(dev, &intel_output->enc, &intel_lvds_enc_funcs,
 			 DRM_MODE_ENCODER_LVDS);

 	drm_mode_connector_attach_encoder(&intel_output->base, &intel_output->enc);
 	intel_output->type = INTEL_OUTPUT_LVDS;

 	drm_encoder_helper_add(encoder, &intel_lvds_helper_funcs);
 	drm_connector_helper_add(connector, &intel_lvds_connector_helper_funcs);
 	connector->display_info.subpixel_order = SubPixelHorizontalRGB;
 	connector->interlace_allowed = false;
 	connector->doublescan_allowed = false;


 	/*
 	 * LVDS discovery:
 	 * 1) check for EDID on DDC
 	 * 2) check for VBT data
 	 * 3) check to see if LVDS is already on
 	 *    if none of the above, no panel
 	 * 4) make sure lid is open
 	 *    if closed, act like it's not there for now
 	 */

 	/* Set up the DDC bus. */
 	intel_output->ddc_bus = intel_i2c_create(dev, GPIOC, "LVDSDDC_C");
 	if (!intel_output->ddc_bus) {
 		dev_printk(KERN_ERR, &dev->pdev->dev, "DDC bus registration "
 			   "failed.\n");
 		goto failed;
 	}

 	/*
 	 * Attempt to get the fixed panel mode from DDC.  Assume that the
 	 * preferred mode is the right one.
 	 */
 	intel_ddc_get_modes(intel_output);

 	list_for_each_entry(scan, &connector->probed_modes, head) {
 		mutex_lock(&dev->mode_config.mutex);
 		if (scan->type & DRM_MODE_TYPE_PREFERRED) {
 			dev_priv->panel_fixed_mode =
 				drm_mode_duplicate(dev, scan);
 			mutex_unlock(&dev->mode_config.mutex);
 			goto out; /* FIXME: check for quirks */
 		}
 		mutex_unlock(&dev->mode_config.mutex);
 	}

 	/* Failed to get EDID, what about VBT? */
 	if (dev_priv->vbt_mode) {
 		mutex_lock(&dev->mode_config.mutex);
 		dev_priv->panel_fixed_mode =
 			drm_mode_duplicate(dev, dev_priv->vbt_mode);
 		mutex_unlock(&dev->mode_config.mutex);
 		if (dev_priv->panel_fixed_mode) {
 			dev_priv->panel_fixed_mode->type |=
 				DRM_MODE_TYPE_PREFERRED;
 			drm_mode_probed_add(connector,
 					    dev_priv->panel_fixed_mode);
 			goto out;
 		}
 	}

 	/*
 	 * If we didn't get EDID, try checking if the panel is already turned
 	 * on.  If so, assume that whatever is currently programmed is the
 	 * correct mode.
 	 */
 	lvds = I915_READ(LVDS);
 	pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
 	crtc = intel_get_crtc_from_pipe(dev, pipe);

 	if (crtc && (lvds & LVDS_PORT_EN)) {
 		dev_priv->panel_fixed_mode = intel_crtc_mode_get(dev, crtc);
 		if (dev_priv->panel_fixed_mode) {
 			dev_priv->panel_fixed_mode->type |=
 				DRM_MODE_TYPE_PREFERRED;
 			goto out; /* FIXME: check for quirks */
 		}
 	}

 	/* If we still don't have a mode after all that, give up. */
 	if (!dev_priv->panel_fixed_mode)
 		goto failed;

 	/* FIXME: detect aopen & mac mini type stuff automatically? */
 	/*
 	 * Blacklist machines with BIOSes that list an LVDS panel without
 	 * actually having one.
 	 */
 	if (IS_I945GM(dev)) {
 		/* aopen mini pc */
 		if (dev->pdev->subsystem_vendor == 0xa0a0)
 			goto failed;

 		if ((dev->pdev->subsystem_vendor == 0x8086) &&
 		    (dev->pdev->subsystem_device == 0x7270)) {
 			/* It's a Mac Mini or Macbook Pro.
 			 *
 			 * Apple hardware is out to get us.  The macbook pro
 			 * has a real LVDS panel, but the mac mini does not,
 			 * and they have the same device IDs.  We'll
 			 * distinguish by panel size, on the assumption
 			 * that Apple isn't about to make any machines with an
 			 * 800x600 display.
 			 */

 			if (dev_priv->panel_fixed_mode != NULL &&
 			    dev_priv->panel_fixed_mode->hdisplay == 800 &&
 			    dev_priv->panel_fixed_mode->vdisplay == 600) {
 				DRM_DEBUG("Suspected Mac Mini, ignoring the LVDS\n");
 				goto failed;
 			}
 		}
 	}


 out:
 	drm_sysfs_connector_add(connector);
 	return;

 failed:
 	DRM_DEBUG("No LVDS modes found, disabling.\n");
 	if (intel_output->ddc_bus)
 		intel_i2c_destroy(intel_output->ddc_bus);
 	drm_connector_cleanup(connector);
 	kfree(connector);
 }
	/*
	* Copyright © 2006-2007 Intel Corporation
	* Copyright (c) 2006 Dave Airlie <airlied@linux.ie>
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice (including the next
	* paragraph) shall be included in all copies or substantial portions of the
	* Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
	* DEALINGS IN THE SOFTWARE.
	*
	* Authors:
	* Eric Anholt <eric@anholt.net>
	* Dave Airlie <airlied@linux.ie>
	* Jesse Barnes <jesse.barnes@intel.com>
	*/

	#include <linux/i2c.h>
	#include "drmP.h"
	#include "drm.h"
	#include "drm_crtc.h"
	#include "drm_edid.h"
	#include "intel_drv.h"
	#include "i915_drm.h"
	#include "i915_drv.h"

	/**
	* Sets the backlight level.
	*
	* \param level backlight level, from 0 to intel_lvds_get_max_backlight().
	*/
	static void intel_lvds_set_backlight(struct drm_device *dev, int level)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 blc_pwm_ctl;

	blc_pwm_ctl = I915_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
	I915_WRITE(BLC_PWM_CTL, (blc_pwm_ctl \|
	(level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
	}

	/**
	* Returns the maximum level of the backlight duty cycle field.
	*/
	static u32 intel_lvds_get_max_backlight(struct drm_device *dev)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;

	return ((I915_READ(BLC_PWM_CTL) & BACKLIGHT_MODULATION_FREQ_MASK) >>
	BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
	}

	/**
	* Sets the power state for the panel.
	*/
	static void intel_lvds_set_power(struct drm_device *dev, bool on)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;
	u32 pp_status;

	if (on) {
	I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) \|
	POWER_TARGET_ON);
	do {
	pp_status = I915_READ(PP_STATUS);
	} while ((pp_status & PP_ON) == 0);

	intel_lvds_set_backlight(dev, dev_priv->backlight_duty_cycle);
	} else {
	intel_lvds_set_backlight(dev, 0);

	I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) &
	~POWER_TARGET_ON);
	do {
	pp_status = I915_READ(PP_STATUS);
	} while (pp_status & PP_ON);
	}
	}

	static void intel_lvds_dpms(struct drm_encoder *encoder, int mode)
	{
	struct drm_device *dev = encoder->dev;

	if (mode == DRM_MODE_DPMS_ON)
	intel_lvds_set_power(dev, true);
	else
	intel_lvds_set_power(dev, false);

	/* XXX: We never power down the LVDS pairs. */
	}

	static void intel_lvds_save(struct drm_connector *connector)
	{
	struct drm_device *dev = connector->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	dev_priv->savePP_ON = I915_READ(PP_ON_DELAYS);
	dev_priv->savePP_OFF = I915_READ(PP_OFF_DELAYS);
	dev_priv->savePP_CONTROL = I915_READ(PP_CONTROL);
	dev_priv->savePP_DIVISOR = I915_READ(PP_DIVISOR);
	dev_priv->saveBLC_PWM_CTL = I915_READ(BLC_PWM_CTL);
	dev_priv->backlight_duty_cycle = (dev_priv->saveBLC_PWM_CTL &
	BACKLIGHT_DUTY_CYCLE_MASK);

	/*
	* If the light is off at server startup, just make it full brightness
	*/
	if (dev_priv->backlight_duty_cycle == 0)
	dev_priv->backlight_duty_cycle =
	intel_lvds_get_max_backlight(dev);
	}

	static void intel_lvds_restore(struct drm_connector *connector)
	{
	struct drm_device *dev = connector->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	I915_WRITE(BLC_PWM_CTL, dev_priv->saveBLC_PWM_CTL);
	I915_WRITE(PP_ON_DELAYS, dev_priv->savePP_ON);
	I915_WRITE(PP_OFF_DELAYS, dev_priv->savePP_OFF);
	I915_WRITE(PP_DIVISOR, dev_priv->savePP_DIVISOR);
	I915_WRITE(PP_CONTROL, dev_priv->savePP_CONTROL);
	if (dev_priv->savePP_CONTROL & POWER_TARGET_ON)
	intel_lvds_set_power(dev, true);
	else
	intel_lvds_set_power(dev, false);
	}

	static int intel_lvds_mode_valid(struct drm_connector *connector,
	struct drm_display_mode *mode)
	{
	struct drm_device *dev = connector->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_display_mode *fixed_mode = dev_priv->panel_fixed_mode;

	if (fixed_mode) {
	if (mode->hdisplay > fixed_mode->hdisplay)
	return MODE_PANEL;
	if (mode->vdisplay > fixed_mode->vdisplay)
	return MODE_PANEL;
	}

	return MODE_OK;
	}

	static bool intel_lvds_mode_fixup(struct drm_encoder *encoder,
	struct drm_display_mode *mode,
	struct drm_display_mode *adjusted_mode)
	{
	struct drm_device *dev = encoder->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->crtc);
	struct drm_encoder *tmp_encoder;

	/* Should never happen!! */
	if (!IS_I965G(dev) && intel_crtc->pipe == 0) {
	printk(KERN_ERR "Can't support LVDS on pipe A\n");
	return false;
	}

	/* Should never happen!! */
	list_for_each_entry(tmp_encoder, &dev->mode_config.encoder_list, head) {
	if (tmp_encoder != encoder && tmp_encoder->crtc == encoder->crtc) {
	printk(KERN_ERR "Can't enable LVDS and another "
	"encoder on the same pipe\n");
	return false;
	}
	}

	/*
	* If we have timings from the BIOS for the panel, put them in
	* to the adjusted mode. The CRTC will be set up for this mode,
	* with the panel scaling set up to source from the H/VDisplay
	* of the original mode.
	*/
	if (dev_priv->panel_fixed_mode != NULL) {
	adjusted_mode->hdisplay = dev_priv->panel_fixed_mode->hdisplay;
	adjusted_mode->hsync_start =
	dev_priv->panel_fixed_mode->hsync_start;
	adjusted_mode->hsync_end =
	dev_priv->panel_fixed_mode->hsync_end;
	adjusted_mode->htotal = dev_priv->panel_fixed_mode->htotal;
	adjusted_mode->vdisplay = dev_priv->panel_fixed_mode->vdisplay;
	adjusted_mode->vsync_start =
	dev_priv->panel_fixed_mode->vsync_start;
	adjusted_mode->vsync_end =
	dev_priv->panel_fixed_mode->vsync_end;
	adjusted_mode->vtotal = dev_priv->panel_fixed_mode->vtotal;
	adjusted_mode->clock = dev_priv->panel_fixed_mode->clock;
	drm_mode_set_crtcinfo(adjusted_mode, CRTC_INTERLACE_HALVE_V);
	}

	/*
	* XXX: It would be nice to support lower refresh rates on the
	* panels to reduce power consumption, and perhaps match the
	* user's requested refresh rate.
	*/

	return true;
	}

	static void intel_lvds_prepare(struct drm_encoder *encoder)
	{
	struct drm_device *dev = encoder->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	dev_priv->saveBLC_PWM_CTL = I915_READ(BLC_PWM_CTL);
	dev_priv->backlight_duty_cycle = (dev_priv->saveBLC_PWM_CTL &
	BACKLIGHT_DUTY_CYCLE_MASK);

	intel_lvds_set_power(dev, false);
	}

	static void intel_lvds_commit( struct drm_encoder *encoder)
	{
	struct drm_device *dev = encoder->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (dev_priv->backlight_duty_cycle == 0)
	dev_priv->backlight_duty_cycle =
	intel_lvds_get_max_backlight(dev);

	intel_lvds_set_power(dev, true);
	}

	static void intel_lvds_mode_set(struct drm_encoder *encoder,
	struct drm_display_mode *mode,
	struct drm_display_mode *adjusted_mode)
	{
	struct drm_device *dev = encoder->dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->crtc);
	u32 pfit_control;

	/*
	* The LVDS pin pair will already have been turned on in the
	* intel_crtc_mode_set since it has a large impact on the DPLL
	* settings.
	*/

	/*
	* Enable automatic panel scaling so that non-native modes fill the
	* screen. Should be enabled before the pipe is enabled, according to
	* register description and PRM.
	*/
	if (mode->hdisplay != adjusted_mode->hdisplay \|\|
	mode->vdisplay != adjusted_mode->vdisplay)
	pfit_control = (PFIT_ENABLE \| VERT_AUTO_SCALE \|
	HORIZ_AUTO_SCALE \| VERT_INTERP_BILINEAR \|
	HORIZ_INTERP_BILINEAR);
	else
	pfit_control = 0;

	if (!IS_I965G(dev)) {
	if (dev_priv->panel_wants_dither)
	pfit_control \|= PANEL_8TO6_DITHER_ENABLE;
	}
	else
	pfit_control \|= intel_crtc->pipe << PFIT_PIPE_SHIFT;

	I915_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 intel_lvds_detect(struct drm_connector *connector)
	{
	return connector_status_connected;
	}

	/**
	* Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
	*/
	static int intel_lvds_get_modes(struct drm_connector *connector)
	{
	struct drm_device *dev = connector->dev;
	struct intel_output *intel_output = to_intel_output(connector);
	struct drm_i915_private *dev_priv = dev->dev_private;
	int ret = 0;

	ret = intel_ddc_get_modes(intel_output);

	if (ret)
	return ret;

	/* Didn't get an EDID, so
	* Set wide sync ranges so we get all modes
	* handed to valid_mode for checking
	*/
	connector->display_info.min_vfreq = 0;
	connector->display_info.max_vfreq = 200;
	connector->display_info.min_hfreq = 0;
	connector->display_info.max_hfreq = 200;

	if (dev_priv->panel_fixed_mode != NULL) {
	struct drm_display_mode *mode;

	mutex_lock(&dev->mode_config.mutex);
	mode = drm_mode_duplicate(dev, dev_priv->panel_fixed_mode);
	drm_mode_probed_add(connector, mode);
	mutex_unlock(&dev->mode_config.mutex);

	return 1;
	}

	return 0;
	}

	/**
	* intel_lvds_destroy - unregister and free LVDS structures
	* @connector: connector to free
	*
	* Unregister the DDC bus for this connector then free the driver private
	* structure.
	*/
	static void intel_lvds_destroy(struct drm_connector *connector)
	{
	struct intel_output *intel_output = to_intel_output(connector);

	if (intel_output->ddc_bus)
	intel_i2c_destroy(intel_output->ddc_bus);
	drm_sysfs_connector_remove(connector);
	drm_connector_cleanup(connector);
	kfree(connector);
	}

	static int intel_lvds_set_property(struct drm_connector *connector,
	struct drm_property *property,
	uint64_t value)
	{
	struct drm_device *dev = connector->dev;

	if (property == dev->mode_config.dpms_property && connector->encoder)
	intel_lvds_dpms(connector->encoder, (uint32_t)(value & 0xf));

	return 0;
	}

	static const struct drm_encoder_helper_funcs intel_lvds_helper_funcs = {
	.dpms = intel_lvds_dpms,
	.mode_fixup = intel_lvds_mode_fixup,
	.prepare = intel_lvds_prepare,
	.mode_set = intel_lvds_mode_set,
	.commit = intel_lvds_commit,
	};

	static const struct drm_connector_helper_funcs intel_lvds_connector_helper_funcs = {
	.get_modes = intel_lvds_get_modes,
	.mode_valid = intel_lvds_mode_valid,
	.best_encoder = intel_best_encoder,
	};

	static const struct drm_connector_funcs intel_lvds_connector_funcs = {
	.save = intel_lvds_save,
	.restore = intel_lvds_restore,
	.detect = intel_lvds_detect,
	.fill_modes = drm_helper_probe_single_connector_modes,
	.set_property = intel_lvds_set_property,
	.destroy = intel_lvds_destroy,
	};


	static void intel_lvds_enc_destroy(struct drm_encoder *encoder)
	{
	drm_encoder_cleanup(encoder);
	}

	static const struct drm_encoder_funcs intel_lvds_enc_funcs = {
	.destroy = intel_lvds_enc_destroy,
	};



	/**
	* intel_lvds_init - setup LVDS connectors on this device
	* @dev: drm device
	*
	* Create the connector, register the LVDS DDC bus, and try to figure out what
	* modes we can display on the LVDS panel (if present).
	*/
	void intel_lvds_init(struct drm_device *dev)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct intel_output *intel_output;
	struct drm_connector *connector;
	struct drm_encoder *encoder;
	struct drm_display_mode scan; / modes, bios_mode; */
	struct drm_crtc *crtc;
	u32 lvds;
	int pipe;

	intel_output = kzalloc(sizeof(struct intel_output), GFP_KERNEL);
	if (!intel_output) {
	return;
	}

	connector = &intel_output->base;
	encoder = &intel_output->enc;
	drm_connector_init(dev, &intel_output->base, &intel_lvds_connector_funcs,
	DRM_MODE_CONNECTOR_LVDS);

	drm_encoder_init(dev, &intel_output->enc, &intel_lvds_enc_funcs,
	DRM_MODE_ENCODER_LVDS);

	drm_mode_connector_attach_encoder(&intel_output->base, &intel_output->enc);
	intel_output->type = INTEL_OUTPUT_LVDS;

	drm_encoder_helper_add(encoder, &intel_lvds_helper_funcs);
	drm_connector_helper_add(connector, &intel_lvds_connector_helper_funcs);
	connector->display_info.subpixel_order = SubPixelHorizontalRGB;
	connector->interlace_allowed = false;
	connector->doublescan_allowed = false;


	/*
	* LVDS discovery:
	* 1) check for EDID on DDC
	* 2) check for VBT data
	* 3) check to see if LVDS is already on
	* if none of the above, no panel
	* 4) make sure lid is open
	* if closed, act like it's not there for now
	*/

	/* Set up the DDC bus. */
	intel_output->ddc_bus = intel_i2c_create(dev, GPIOC, "LVDSDDC_C");
	if (!intel_output->ddc_bus) {
	dev_printk(KERN_ERR, &dev->pdev->dev, "DDC bus registration "
	"failed.\n");
	goto failed;
	}

	/*
	* Attempt to get the fixed panel mode from DDC. Assume that the
	* preferred mode is the right one.
	*/
	intel_ddc_get_modes(intel_output);

	list_for_each_entry(scan, &connector->probed_modes, head) {
	mutex_lock(&dev->mode_config.mutex);
	if (scan->type & DRM_MODE_TYPE_PREFERRED) {
	dev_priv->panel_fixed_mode =
	drm_mode_duplicate(dev, scan);
	mutex_unlock(&dev->mode_config.mutex);
	goto out; /* FIXME: check for quirks */
	}
	mutex_unlock(&dev->mode_config.mutex);
	}

	/* Failed to get EDID, what about VBT? */
	if (dev_priv->vbt_mode) {
	mutex_lock(&dev->mode_config.mutex);
	dev_priv->panel_fixed_mode =
	drm_mode_duplicate(dev, dev_priv->vbt_mode);
	mutex_unlock(&dev->mode_config.mutex);
	if (dev_priv->panel_fixed_mode) {
	dev_priv->panel_fixed_mode->type \|=
	DRM_MODE_TYPE_PREFERRED;
	drm_mode_probed_add(connector,
	dev_priv->panel_fixed_mode);
	goto out;
	}
	}

	/*
	* If we didn't get EDID, try checking if the panel is already turned
	* on. If so, assume that whatever is currently programmed is the
	* correct mode.
	*/
	lvds = I915_READ(LVDS);
	pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
	crtc = intel_get_crtc_from_pipe(dev, pipe);

	if (crtc && (lvds & LVDS_PORT_EN)) {
	dev_priv->panel_fixed_mode = intel_crtc_mode_get(dev, crtc);
	if (dev_priv->panel_fixed_mode) {
	dev_priv->panel_fixed_mode->type \|=
	DRM_MODE_TYPE_PREFERRED;
	goto out; /* FIXME: check for quirks */
	}
	}

	/* If we still don't have a mode after all that, give up. */
	if (!dev_priv->panel_fixed_mode)
	goto failed;

	/* FIXME: detect aopen & mac mini type stuff automatically? */
	/*
	* Blacklist machines with BIOSes that list an LVDS panel without
	* actually having one.
	*/
	if (IS_I945GM(dev)) {
	/* aopen mini pc */
	if (dev->pdev->subsystem_vendor == 0xa0a0)
	goto failed;

	if ((dev->pdev->subsystem_vendor == 0x8086) &&
	(dev->pdev->subsystem_device == 0x7270)) {
	/* It's a Mac Mini or Macbook Pro.
	*
	* Apple hardware is out to get us. The macbook pro
	* has a real LVDS panel, but the mac mini does not,
	* and they have the same device IDs. We'll
	* distinguish by panel size, on the assumption
	* that Apple isn't about to make any machines with an
	* 800x600 display.
	*/

	if (dev_priv->panel_fixed_mode != NULL &&
	dev_priv->panel_fixed_mode->hdisplay == 800 &&
	dev_priv->panel_fixed_mode->vdisplay == 600) {
	DRM_DEBUG("Suspected Mac Mini, ignoring the LVDS\n");
	goto failed;
	}
	}
	}


	out:
	drm_sysfs_connector_add(connector);
	return;

	failed:
	DRM_DEBUG("No LVDS modes found, disabling.\n");
	if (intel_output->ddc_bus)
	intel_i2c_destroy(intel_output->ddc_bus);
	drm_connector_cleanup(connector);
	kfree(connector);
	}