gma500: begin adding CDV specific code

A lot of the intel_display stuff is duplicated, but we will add it first,
clean it up and then investigate the best way to merge stuff.

This first block integrates the various basic chunks of the CDV display setup.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 718 insertions, 0 deletions

diff --git a/drivers/staging/gma500/cdv_intel_lvds.c b/drivers/staging/gma500/cdv_intel_lvds.c
new file mode 100644
index 000000000000..d9b2290dd35c
--- /dev/null
+++ b/drivers/staging/gma500/cdv_intel_lvds.c
@@ -0,0 +1,718 @@
+/*
+ * Copyright © 2006-2011 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Authors:
+ *	Eric Anholt <eric@anholt.net>
+ *	Dave Airlie <airlied@linux.ie>
+ *	Jesse Barnes <jesse.barnes@intel.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/dmi.h>
+#include <drm/drmP.h>
+
+#include "intel_bios.h"
+#include "psb_drv.h"
+#include "psb_intel_drv.h"
+#include "psb_intel_reg.h"
+#include "power.h"
+#include <linux/pm_runtime.h>
+#include "cdv_device.h"
+
+/**
+ * LVDS I2C backlight control macros
+ */
+#define BRIGHTNESS_MAX_LEVEL 100
+#define BRIGHTNESS_MASK 0xFF
+#define BLC_I2C_TYPE	0x01
+#define BLC_PWM_TYPT	0x02
+
+#define BLC_POLARITY_NORMAL 0
+#define BLC_POLARITY_INVERSE 1
+
+#define PSB_BLC_MAX_PWM_REG_FREQ       (0xFFFE)
+#define PSB_BLC_MIN_PWM_REG_FREQ	(0x2)
+#define PSB_BLC_PWM_PRECISION_FACTOR	(10)
+#define PSB_BACKLIGHT_PWM_CTL_SHIFT	(16)
+#define PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR (0xFFFE)
+
+struct cdv_intel_lvds_priv {
+	/**
+	 * Saved LVDO output states
+	 */
+	uint32_t savePP_ON;
+	uint32_t savePP_OFF;
+	uint32_t saveLVDS;
+	uint32_t savePP_CONTROL;
+	uint32_t savePP_CYCLE;
+	uint32_t savePFIT_CONTROL;
+	uint32_t savePFIT_PGM_RATIOS;
+	uint32_t saveBLC_PWM_CTL;
+};
+
+/*
+ * Returns the maximum level of the backlight duty cycle field.
+ */
+static u32 cdv_intel_lvds_get_max_backlight(struct drm_device *dev)
+{
+	struct drm_psb_private *dev_priv = dev->dev_private;
+	u32 retval;
+
+	if (gma_power_begin(dev, false)) {
+		retval = ((REG_READ(BLC_PWM_CTL) &
+			  BACKLIGHT_MODULATION_FREQ_MASK) >>
+			  BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
+
+		gma_power_end(dev);
+	} else
+		retval = ((dev_priv->saveBLC_PWM_CTL &
+			  BACKLIGHT_MODULATION_FREQ_MASK) >>
+			  BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;
+
+	return retval;
+}
+
+/*
+ * Set LVDS backlight level by I2C command
+ */
+static int cdv_lvds_i2c_set_brightness(struct drm_device *dev,
+					unsigned int level)
+{
+	struct drm_psb_private *dev_priv = dev->dev_private;
+	struct psb_intel_i2c_chan *lvds_i2c_bus = dev_priv->lvds_i2c_bus;
+	u8 out_buf[2];
+	unsigned int blc_i2c_brightness;
+
+	struct i2c_msg msgs[] = {
+		{
+			.addr = lvds_i2c_bus->slave_addr,
+			.flags = 0,
+			.len = 2,
+			.buf = out_buf,
+		}
+	};
+
+	blc_i2c_brightness = BRIGHTNESS_MASK & ((unsigned int)level *
+			     BRIGHTNESS_MASK /
+			     BRIGHTNESS_MAX_LEVEL);
+
+	if (dev_priv->lvds_bl->pol == BLC_POLARITY_INVERSE)
+		blc_i2c_brightness = BRIGHTNESS_MASK - blc_i2c_brightness;
+
+	out_buf[0] = dev_priv->lvds_bl->brightnesscmd;
+	out_buf[1] = (u8)blc_i2c_brightness;
+
+	if (i2c_transfer(&lvds_i2c_bus->adapter, msgs, 1) == 1)
+		return 0;
+
+	DRM_ERROR("I2C transfer error\n");
+	return -1;
+}
+
+
+static int cdv_lvds_pwm_set_brightness(struct drm_device *dev, int level)
+{
+	struct drm_psb_private *dev_priv = dev->dev_private;
+
+	u32 max_pwm_blc;
+	u32 blc_pwm_duty_cycle;
+
+	max_pwm_blc = cdv_intel_lvds_get_max_backlight(dev);
+
+	/*BLC_PWM_CTL Should be initiated while backlight device init*/
+	BUG_ON((max_pwm_blc & PSB_BLC_MAX_PWM_REG_FREQ) == 0);
+
+	blc_pwm_duty_cycle = level * max_pwm_blc / BRIGHTNESS_MAX_LEVEL;
+
+	if (dev_priv->lvds_bl->pol == BLC_POLARITY_INVERSE)
+		blc_pwm_duty_cycle = max_pwm_blc - blc_pwm_duty_cycle;
+
+	blc_pwm_duty_cycle &= PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR;
+	REG_WRITE(BLC_PWM_CTL,
+		  (max_pwm_blc << PSB_BACKLIGHT_PWM_CTL_SHIFT) |
+		  (blc_pwm_duty_cycle));
+
+	return 0;
+}
+
+/*
+ * Set LVDS backlight level either by I2C or PWM
+ */
+void cdv_intel_lvds_set_brightness(struct drm_device *dev, int level)
+{
+	struct drm_psb_private *dev_priv = dev->dev_private;
+
+	if (!dev_priv->lvds_bl) {
+		DRM_ERROR("NO LVDS Backlight Info\n");
+		return;
+	}
+
+	if (dev_priv->lvds_bl->type == BLC_I2C_TYPE)
+		cdv_lvds_i2c_set_brightness(dev, level);
+	else
+		cdv_lvds_pwm_set_brightness(dev, level);
+}
+
+/**
+ * Sets the backlight level.
+ *
+ * level backlight level, from 0 to cdv_intel_lvds_get_max_backlight().
+ */
+static void cdv_intel_lvds_set_backlight(struct drm_device *dev, int level)
+{
+	struct drm_psb_private *dev_priv = dev->dev_private;
+	u32 blc_pwm_ctl;
+
+	if (gma_power_begin(dev, false)) {
+		blc_pwm_ctl =
+			REG_READ(BLC_PWM_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
+		REG_WRITE(BLC_PWM_CTL,
+				(blc_pwm_ctl |
+				(level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
+		gma_power_end(dev);
+	} else {
+		blc_pwm_ctl = dev_priv->saveBLC_PWM_CTL &
+				~BACKLIGHT_DUTY_CYCLE_MASK;
+		dev_priv->saveBLC_PWM_CTL = (blc_pwm_ctl |
+					(level << BACKLIGHT_DUTY_CYCLE_SHIFT));
+	}
+}
+
+/**
+ * Sets the power state for the panel.
+ */
+static void cdv_intel_lvds_set_power(struct drm_device *dev,
+				 struct psb_intel_output *output, bool on)
+{
+	u32 pp_status;
+
+	if (!gma_power_begin(dev, true))
+	        return;
+
+	if (on) {
+		REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) |
+			  POWER_TARGET_ON);
+		do {
+			pp_status = REG_READ(PP_STATUS);
+		} while ((pp_status & PP_ON) == 0);
+
+		cdv_intel_lvds_set_backlight(dev,
+					 output->
+					 mode_dev->backlight_duty_cycle);
+	} else {
+		cdv_intel_lvds_set_backlight(dev, 0);
+
+		REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) &
+			  ~POWER_TARGET_ON);
+		do {
+			pp_status = REG_READ(PP_STATUS);
+		} while (pp_status & PP_ON);
+	}
+	gma_power_end(dev);
+}
+
+static void cdv_intel_lvds_encoder_dpms(struct drm_encoder *encoder, int mode)
+{
+	struct drm_device *dev = encoder->dev;
+	struct psb_intel_output *output = enc_to_psb_intel_output(encoder);
+	if (mode == DRM_MODE_DPMS_ON)
+		cdv_intel_lvds_set_power(dev, output, true);
+	else
+		cdv_intel_lvds_set_power(dev, output, false);
+	/* XXX: We never power down the LVDS pairs. */
+}
+
+static void cdv_intel_lvds_save(struct drm_connector *connector)
+{
+}
+
+static void cdv_intel_lvds_restore(struct drm_connector *connector)
+{
+}
+
+int cdv_intel_lvds_mode_valid(struct drm_connector *connector,
+				 struct drm_display_mode *mode)
+{
+	struct psb_intel_output *psb_intel_output =
+				to_psb_intel_output(connector);
+	struct drm_display_mode *fixed_mode =
+	    psb_intel_output->mode_dev->panel_fixed_mode;
+
+	/* just in case */
+	if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
+		return MODE_NO_DBLESCAN;
+
+	/* just in case */
+	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
+		return MODE_NO_INTERLACE;
+
+	if (fixed_mode) {
+		if (mode->hdisplay > fixed_mode->hdisplay)
+			return MODE_PANEL;
+		if (mode->vdisplay > fixed_mode->vdisplay)
+			return MODE_PANEL;
+	}
+	return MODE_OK;
+}
+
+bool cdv_intel_lvds_mode_fixup(struct drm_encoder *encoder,
+				  struct drm_display_mode *mode,
+				  struct drm_display_mode *adjusted_mode)
+{
+	struct psb_intel_mode_device *mode_dev =
+	    enc_to_psb_intel_output(encoder)->mode_dev;
+	struct drm_device *dev = encoder->dev;
+	struct drm_encoder *tmp_encoder;
+	struct drm_display_mode *panel_fixed_mode = mode_dev->panel_fixed_mode;
+
+	/* 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 (panel_fixed_mode != NULL) {
+		adjusted_mode->hdisplay = panel_fixed_mode->hdisplay;
+		adjusted_mode->hsync_start = panel_fixed_mode->hsync_start;
+		adjusted_mode->hsync_end = panel_fixed_mode->hsync_end;
+		adjusted_mode->htotal = panel_fixed_mode->htotal;
+		adjusted_mode->vdisplay = panel_fixed_mode->vdisplay;
+		adjusted_mode->vsync_start = panel_fixed_mode->vsync_start;
+		adjusted_mode->vsync_end = panel_fixed_mode->vsync_end;
+		adjusted_mode->vtotal = panel_fixed_mode->vtotal;
+		adjusted_mode->clock = 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 cdv_intel_lvds_prepare(struct drm_encoder *encoder)
+{
+	struct drm_device *dev = encoder->dev;
+	struct psb_intel_output *output = enc_to_psb_intel_output(encoder);
+	struct psb_intel_mode_device *mode_dev = output->mode_dev;
+
+	if (!gma_power_begin(dev, true))
+		return;
+
+	mode_dev->saveBLC_PWM_CTL = REG_READ(BLC_PWM_CTL);
+	mode_dev->backlight_duty_cycle = (mode_dev->saveBLC_PWM_CTL &
+					  BACKLIGHT_DUTY_CYCLE_MASK);
+
+	cdv_intel_lvds_set_power(dev, output, false);
+
+	gma_power_end(dev);
+}
+
+static void cdv_intel_lvds_commit(struct drm_encoder *encoder)
+{
+	struct drm_device *dev = encoder->dev;
+	struct psb_intel_output *output = enc_to_psb_intel_output(encoder);
+	struct psb_intel_mode_device *mode_dev = output->mode_dev;
+
+	if (mode_dev->backlight_duty_cycle == 0)
+		mode_dev->backlight_duty_cycle =
+		    cdv_intel_lvds_get_max_backlight(dev);
+
+	cdv_intel_lvds_set_power(dev, output, true);
+}
+
+static void cdv_intel_lvds_mode_set(struct drm_encoder *encoder,
+				struct drm_display_mode *mode,
+				struct drm_display_mode *adjusted_mode)
+{
+	struct psb_intel_mode_device *mode_dev =
+	    enc_to_psb_intel_output(encoder)->mode_dev;
+	struct drm_device *dev = encoder->dev;
+	u32 pfit_control;
+
+	/*
+	 * The LVDS pin pair will already have been turned on in the
+	 * cdv_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 (mode_dev->panel_wants_dither)
+		pfit_control |= PANEL_8TO6_DITHER_ENABLE;
+
+	REG_WRITE(PFIT_CONTROL, pfit_control);
+}
+
+/**
+ * Detect the LVDS connection.
+ *
+ * This always returns CONNECTOR_STATUS_CONNECTED.
+ * This connector should only have
+ * been set up if the LVDS was actually connected anyway.
+ */
+static enum drm_connector_status cdv_intel_lvds_detect(struct drm_connector *connector, bool force)
+{
+	return connector_status_connected;
+}
+
+/**
+ * Return the list of DDC modes if available, or the BIOS fixed mode otherwise.
+ */
+static int cdv_intel_lvds_get_modes(struct drm_connector *connector)
+{
+	struct drm_device *dev = connector->dev;
+	struct psb_intel_output *psb_intel_output =
+					to_psb_intel_output(connector);
+	struct psb_intel_mode_device *mode_dev =
+					psb_intel_output->mode_dev;
+	int ret;
+
+	ret = psb_intel_ddc_get_modes(psb_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 (mode_dev->panel_fixed_mode != NULL) {
+		struct drm_display_mode *mode =
+		    drm_mode_duplicate(dev, mode_dev->panel_fixed_mode);
+		drm_mode_probed_add(connector, mode);
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * cdv_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.
+ */
+void cdv_intel_lvds_destroy(struct drm_connector *connector)
+{
+	struct psb_intel_output *psb_intel_output =
+					to_psb_intel_output(connector);
+
+	if (psb_intel_output->ddc_bus)
+		psb_intel_i2c_destroy(psb_intel_output->ddc_bus);
+	drm_sysfs_connector_remove(connector);
+	drm_connector_cleanup(connector);
+	kfree(connector);
+}
+
+int cdv_intel_lvds_set_property(struct drm_connector *connector,
+				       struct drm_property *property,
+				       uint64_t value)
+{
+	struct drm_encoder *encoder = connector->encoder;
+
+	if (!strcmp(property->name, "scaling mode") && encoder) {
+		struct psb_intel_crtc *crtc =
+					to_psb_intel_crtc(encoder->crtc);
+		uint64_t curValue;
+
+		if (!crtc)
+			return -1;
+
+		switch (value) {
+		case DRM_MODE_SCALE_FULLSCREEN:
+			break;
+		case DRM_MODE_SCALE_NO_SCALE:
+			break;
+		case DRM_MODE_SCALE_ASPECT:
+			break;
+		default:
+			return -1;
+		}
+
+		if (drm_connector_property_get_value(connector,
+						     property,
+						     &curValue))
+			return -1;
+
+		if (curValue == value)
+			return 0;
+
+		if (drm_connector_property_set_value(connector,
+							property,
+							value))
+			return -1;
+
+		if (crtc->saved_mode.hdisplay != 0 &&
+		    crtc->saved_mode.vdisplay != 0) {
+			if (!drm_crtc_helper_set_mode(encoder->crtc,
+						      &crtc->saved_mode,
+						      encoder->crtc->x,
+						      encoder->crtc->y,
+						      encoder->crtc->fb))
+				return -1;
+		}
+	} else if (!strcmp(property->name, "backlight") && encoder) {
+		if (drm_connector_property_set_value(connector,
+							property,
+							value))
+			return -1;
+		else {
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+                	struct drm_psb_private *dev_priv =
+						encoder->dev->dev_private;
+			struct backlight_device *bd = dev_priv->backlight_device;
+			bd->props.brightness = value;
+			backlight_update_status(bd);
+#endif
+		}
+	} else if (!strcmp(property->name, "DPMS") && encoder) {
+		struct drm_encoder_helper_funcs *helpers = encoder->helper_private;
+		helpers->dpms(encoder, value);
+	}
+	return 0;
+}
+
+static const struct drm_encoder_helper_funcs cdv_intel_lvds_helper_funcs = {
+	.dpms = cdv_intel_lvds_encoder_dpms,
+	.mode_fixup = cdv_intel_lvds_mode_fixup,
+	.prepare = cdv_intel_lvds_prepare,
+	.mode_set = cdv_intel_lvds_mode_set,
+	.commit = cdv_intel_lvds_commit,
+};
+
+static const struct drm_connector_helper_funcs
+    cdv_intel_lvds_connector_helper_funcs = {
+	.get_modes = cdv_intel_lvds_get_modes,
+	.mode_valid = cdv_intel_lvds_mode_valid,
+	.best_encoder = psb_intel_best_encoder,
+};
+
+static const struct drm_connector_funcs cdv_intel_lvds_connector_funcs = {
+	.dpms = drm_helper_connector_dpms,
+	.save = cdv_intel_lvds_save,
+	.restore = cdv_intel_lvds_restore,
+	.detect = cdv_intel_lvds_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.set_property = cdv_intel_lvds_set_property,
+	.destroy = cdv_intel_lvds_destroy,
+};
+
+
+static void cdv_intel_lvds_enc_destroy(struct drm_encoder *encoder)
+{
+	drm_encoder_cleanup(encoder);
+}
+
+const struct drm_encoder_funcs cdv_intel_lvds_enc_funcs = {
+	.destroy = cdv_intel_lvds_enc_destroy,
+};
+
+/**
+ * cdv_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 cdv_intel_lvds_init(struct drm_device *dev,
+		     struct psb_intel_mode_device *mode_dev)
+{
+	struct psb_intel_output *psb_intel_output;
+	struct cdv_intel_lvds_priv *lvds_priv;
+	struct drm_connector *connector;
+	struct drm_encoder *encoder;
+	struct drm_display_mode *scan;
+	struct drm_crtc *crtc;
+	struct drm_psb_private *dev_priv = dev->dev_private;
+	u32 lvds;
+	int pipe;
+
+	psb_intel_output = kzalloc(sizeof(struct psb_intel_output) +
+			sizeof(struct cdv_intel_lvds_priv), GFP_KERNEL);
+	if (!psb_intel_output)
+		return;
+
+	lvds_priv = (struct cdv_intel_lvds_priv *)(psb_intel_output + 1);
+
+	psb_intel_output->dev_priv = lvds_priv;
+
+	psb_intel_output->mode_dev = mode_dev;
+	connector = &psb_intel_output->base;
+	encoder = &psb_intel_output->enc;
+
+
+	drm_connector_init(dev, &psb_intel_output->base,
+			   &cdv_intel_lvds_connector_funcs,
+			   DRM_MODE_CONNECTOR_LVDS);
+
+	drm_encoder_init(dev, &psb_intel_output->enc,
+			 &cdv_intel_lvds_enc_funcs,
+			 DRM_MODE_ENCODER_LVDS);
+
+
+	drm_mode_connector_attach_encoder(&psb_intel_output->base,
+					  &psb_intel_output->enc);
+	psb_intel_output->type = INTEL_OUTPUT_LVDS;
+
+	drm_encoder_helper_add(encoder, &cdv_intel_lvds_helper_funcs);
+	drm_connector_helper_add(connector,
+				 &cdv_intel_lvds_connector_helper_funcs);
+	connector->display_info.subpixel_order = SubPixelHorizontalRGB;
+	connector->interlace_allowed = false;
+	connector->doublescan_allowed = false;
+
+	/*Attach connector properties*/
+	drm_connector_attach_property(connector,
+				      dev->mode_config.scaling_mode_property,
+				      DRM_MODE_SCALE_FULLSCREEN);
+	drm_connector_attach_property(connector,
+				      dev_priv->backlight_property,
+				      BRIGHTNESS_MAX_LEVEL);
+
+	/**
+	 * Set up I2C bus
+	 * FIXME: distroy i2c_bus when exit
+	 */
+	psb_intel_output->i2c_bus = psb_intel_i2c_create(dev,
+							 GPIOB,
+							 "LVDSBLC_B");
+	if (!psb_intel_output->i2c_bus) {
+		dev_printk(KERN_ERR,
+			&dev->pdev->dev, "I2C bus registration failed.\n");
+		goto failed_blc_i2c;
+	}
+	psb_intel_output->i2c_bus->slave_addr = 0x2C;
+	dev_priv->lvds_i2c_bus =  psb_intel_output->i2c_bus;
+
+	/*
+	 * 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. */
+	psb_intel_output->ddc_bus = psb_intel_i2c_create(dev,
+							 GPIOC,
+							 "LVDSDDC_C");
+	if (!psb_intel_output->ddc_bus) {
+		dev_printk(KERN_ERR, &dev->pdev->dev,
+			   "DDC bus registration " "failed.\n");
+		goto failed_ddc;
+	}
+
+	/*
+	 * Attempt to get the fixed panel mode from DDC.  Assume that the
+	 * preferred mode is the right one.
+	 */
+	psb_intel_ddc_get_modes(psb_intel_output);
+	list_for_each_entry(scan, &connector->probed_modes, head) {
+		if (scan->type & DRM_MODE_TYPE_PREFERRED) {
+			mode_dev->panel_fixed_mode =
+			    drm_mode_duplicate(dev, scan);
+			goto out;	/* FIXME: check for quirks */
+		}
+	}
+
+	/* Failed to get EDID, what about VBT? do we need this?*/
+	if (dev_priv->lfp_lvds_vbt_mode) {
+		mode_dev->panel_fixed_mode =
+			drm_mode_duplicate(dev, dev_priv->lfp_lvds_vbt_mode);
+		if (mode_dev->panel_fixed_mode) {
+			mode_dev->panel_fixed_mode->type |=
+				DRM_MODE_TYPE_PREFERRED;
+			goto out;	/* FIXME: check for quirks */
+		}
+	}
+	/*
+	 * 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 = REG_READ(LVDS);
+	pipe = (lvds & LVDS_PIPEB_SELECT) ? 1 : 0;
+	crtc = psb_intel_get_crtc_from_pipe(dev, pipe);
+
+	if (crtc && (lvds & LVDS_PORT_EN)) {
+		mode_dev->panel_fixed_mode =
+		    cdv_intel_crtc_mode_get(dev, crtc);
+		if (mode_dev->panel_fixed_mode) {
+			mode_dev->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 (!mode_dev->panel_fixed_mode) {
+		DRM_DEBUG
+			("Found no modes on the lvds, ignoring the LVDS\n");
+		goto failed_find;
+	}
+
+out:
+	drm_sysfs_connector_add(connector);
+	return;
+
+failed_find:
+	printk(KERN_ERR "Failed find\n");
+	if (psb_intel_output->ddc_bus)
+		psb_intel_i2c_destroy(psb_intel_output->ddc_bus);
+failed_ddc:
+	printk(KERN_ERR "Failed DDC\n");
+	if (psb_intel_output->i2c_bus)
+		psb_intel_i2c_destroy(psb_intel_output->i2c_bus);
+failed_blc_i2c:
+	printk(KERN_ERR "Failed BLC\n");
+	drm_encoder_cleanup(encoder);
+	drm_connector_cleanup(connector);
+	kfree(connector);
+}