cdv_intel_lvds.c

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/*
 * 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 <[email protected]>
 *  Dave Airlie <[email protected]>
 *  Jesse Barnes <[email protected]>
 */

#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"

#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 {
    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->regs.saveBLC_PWM_CTL &
              BACKLIGHT_MODULATION_FREQ_MASK) >>
              BACKLIGHT_MODULATION_FREQ_SHIFT) * 2;

    return retval;
}

#if 0
/*
 * 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);
}
#endif

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->regs.saveBLC_PWM_CTL &
                ~BACKLIGHT_DUTY_CYCLE_MASK;
        dev_priv->regs.saveBLC_PWM_CTL = (blc_pwm_ctl |
                    (level << BACKLIGHT_DUTY_CYCLE_SHIFT));
    }
}

static void cdv_intel_lvds_set_power(struct drm_device *dev,
                     struct drm_encoder *encoder, bool on)
{
    struct drm_psb_private *dev_priv = dev->dev_private;
    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,
                dev_priv->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;
    if (mode == DRM_MODE_DPMS_ON)
        cdv_intel_lvds_set_power(dev, encoder, true);
    else
        cdv_intel_lvds_set_power(dev, encoder, 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)
{
}

static int cdv_intel_lvds_mode_valid(struct drm_connector *connector,
                  struct drm_display_mode *mode)
{
    struct drm_device *dev = connector->dev;
    struct drm_psb_private *dev_priv = dev->dev_private;
    struct drm_display_mode *fixed_mode =
                    dev_priv->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;
}

static bool cdv_intel_lvds_mode_fixup(struct drm_encoder *encoder,
                  const struct drm_display_mode *mode,
                  struct drm_display_mode *adjusted_mode)
{
    struct drm_device *dev = encoder->dev;
    struct drm_psb_private *dev_priv = dev->dev_private;
    struct psb_intel_mode_device *mode_dev = &dev_priv->mode_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 drm_psb_private *dev_priv = dev->dev_private;
    struct psb_intel_mode_device *mode_dev = &dev_priv->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, encoder, false);

    gma_power_end(dev);
}

static void cdv_intel_lvds_commit(struct drm_encoder *encoder)
{
    struct drm_device *dev = encoder->dev;
    struct drm_psb_private *dev_priv = dev->dev_private;
    struct psb_intel_mode_device *mode_dev = &dev_priv->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, encoder, true);
}

static void cdv_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_psb_private *dev_priv = dev->dev_private;
    struct psb_intel_crtc *psb_intel_crtc = to_psb_intel_crtc(
                            encoder->crtc);
    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;

    pfit_control |= psb_intel_crtc->pipe << PFIT_PIPE_SHIFT;

    if (dev_priv->lvds_dither)
        pfit_control |= PANEL_8TO6_DITHER_ENABLE;

    REG_WRITE(PFIT_CONTROL, pfit_control);
}

static enum drm_connector_status cdv_intel_lvds_detect(
                struct drm_connector *connector, bool force)
{
    return connector_status_connected;
}

static int cdv_intel_lvds_get_modes(struct drm_connector *connector)
{
    struct drm_device *dev = connector->dev;
    struct drm_psb_private *dev_priv = dev->dev_private;
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);
    struct psb_intel_mode_device *mode_dev = &dev_priv->mode_dev;
    int ret;

    ret = psb_intel_ddc_get_modes(connector, &psb_intel_encoder->i2c_bus->adapter);

    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;
}

static void cdv_intel_lvds_destroy(struct drm_connector *connector)
{
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);

    if (psb_intel_encoder->i2c_bus)
        psb_intel_i2c_destroy(psb_intel_encoder->i2c_bus);
    drm_sysfs_connector_remove(connector);
    drm_connector_cleanup(connector);
    kfree(connector);
}

static 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
                        gma_backlight_set(encoder->dev, value);
    } 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);
}

static const struct drm_encoder_funcs cdv_intel_lvds_enc_funcs = {
    .destroy = cdv_intel_lvds_enc_destroy,
};

/*
 * Enumerate the child dev array parsed from VBT to check whether
 * the LVDS is present.
 * If it is present, return 1.
 * If it is not present, return false.
 * If no child dev is parsed from VBT, it assumes that the LVDS is present.
 */
static bool lvds_is_present_in_vbt(struct drm_device *dev,
                   u8 *i2c_pin)
{
    struct drm_psb_private *dev_priv = dev->dev_private;
    int i;

    if (!dev_priv->child_dev_num)
        return true;

    for (i = 0; i < dev_priv->child_dev_num; i++) {
        struct child_device_config *child = dev_priv->child_dev + i;

        /* If the device type is not LFP, continue.
         * We have to check both the new identifiers as well as the
         * old for compatibility with some BIOSes.
         */
        if (child->device_type != DEVICE_TYPE_INT_LFP &&
            child->device_type != DEVICE_TYPE_LFP)
            continue;

        if (child->i2c_pin)
            *i2c_pin = child->i2c_pin;

        /* However, we cannot trust the BIOS writers to populate
         * the VBT correctly.  Since LVDS requires additional
         * information from AIM blocks, a non-zero addin offset is
         * a good indicator that the LVDS is actually present.
         */
        if (child->addin_offset)
            return true;

        /* But even then some BIOS writers perform some black magic
         * and instantiate the device without reference to any
         * additional data.  Trust that if the VBT was written into
         * the OpRegion then they have validated the LVDS's existence.
         */
        if (dev_priv->opregion.vbt)
            return true;
    }

    return false;
}

void cdv_intel_lvds_init(struct drm_device *dev,
             struct psb_intel_mode_device *mode_dev)
{
    struct psb_intel_encoder *psb_intel_encoder;
    struct psb_intel_connector *psb_intel_connector;
    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;
    u8 pin;

    pin = GMBUS_PORT_PANEL;
    if (!lvds_is_present_in_vbt(dev, &pin)) {
        DRM_DEBUG_KMS("LVDS is not present in VBT\n");
        return;
    }

    psb_intel_encoder = kzalloc(sizeof(struct psb_intel_encoder),
                    GFP_KERNEL);
    if (!psb_intel_encoder)
        return;

    psb_intel_connector = kzalloc(sizeof(struct psb_intel_connector),
                      GFP_KERNEL);
    if (!psb_intel_connector)
        goto failed_connector;

    lvds_priv = kzalloc(sizeof(struct cdv_intel_lvds_priv), GFP_KERNEL);
    if (!lvds_priv)
        goto failed_lvds_priv;

    psb_intel_encoder->dev_priv = lvds_priv;

    connector = &psb_intel_connector->base;
    encoder = &psb_intel_encoder->base;


    drm_connector_init(dev, connector,
               &cdv_intel_lvds_connector_funcs,
               DRM_MODE_CONNECTOR_LVDS);

    drm_encoder_init(dev, encoder,
             &cdv_intel_lvds_enc_funcs,
             DRM_MODE_ENCODER_LVDS);


    psb_intel_connector_attach_encoder(psb_intel_connector,
                       psb_intel_encoder);
    psb_intel_encoder->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);

    psb_intel_encoder->i2c_bus = psb_intel_i2c_create(dev,
                             GPIOB,
                             "LVDSBLC_B");
    if (!psb_intel_encoder->i2c_bus) {
        dev_printk(KERN_ERR,
            &dev->pdev->dev, "I2C bus registration failed.\n");
        goto failed_blc_i2c;
    }
    psb_intel_encoder->i2c_bus->slave_addr = 0x2C;
    dev_priv->lvds_i2c_bus = psb_intel_encoder->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_encoder->ddc_bus = psb_intel_i2c_create(dev,
                             GPIOC,
                             "LVDSDDC_C");
    if (!psb_intel_encoder->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(connector,
                &psb_intel_encoder->ddc_bus->adapter);
    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;
    }

    /* setup PWM */
    {
        u32 pwm;

        pwm = REG_READ(BLC_PWM_CTL2);
        if (pipe == 1)
            pwm |= PWM_PIPE_B;
        else
            pwm &= ~PWM_PIPE_B;
        pwm |= PWM_ENABLE;
        REG_WRITE(BLC_PWM_CTL2, pwm);
    }

out:
    drm_sysfs_connector_add(connector);
    return;

failed_find:
    printk(KERN_ERR "Failed find\n");
    if (psb_intel_encoder->ddc_bus)
        psb_intel_i2c_destroy(psb_intel_encoder->ddc_bus);
failed_ddc:
    printk(KERN_ERR "Failed DDC\n");
    if (psb_intel_encoder->i2c_bus)
        psb_intel_i2c_destroy(psb_intel_encoder->i2c_bus);
failed_blc_i2c:
    printk(KERN_ERR "Failed BLC\n");
    drm_encoder_cleanup(encoder);
    drm_connector_cleanup(connector);
    kfree(lvds_priv);
failed_lvds_priv:
    kfree(psb_intel_connector);
failed_connector:
    kfree(psb_intel_encoder);
}