psb_intel_lvds.c

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/*
 * Copyright © 2006-2007 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 <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>

/*
 * 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 psb_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;

    struct psb_intel_i2c_chan *i2c_bus;
    struct psb_intel_i2c_chan *ddc_bus;
};


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

    if (gma_power_begin(dev, false)) {
        ret = REG_READ(BLC_PWM_CTL);
        gma_power_end(dev);
    } else /* Powered off, use the saved value */
        ret = dev_priv->regs.saveBLC_PWM_CTL;

    /* Top 15bits hold the frequency mask */
    ret = (ret &  BACKLIGHT_MODULATION_FREQ_MASK) >>
                    BACKLIGHT_MODULATION_FREQ_SHIFT;

        ret *= 2;   /* Return a 16bit range as needed for setting */
        if (ret == 0)
                dev_err(dev->dev, "BL bug: Reg %08x save %08X\n",
                        REG_READ(BLC_PWM_CTL), dev_priv->regs.saveBLC_PWM_CTL);
    return ret;
}

/*
 * Set LVDS backlight level by I2C command
 *
 * FIXME: at some point we need to both track this for PM and also
 * disable runtime pm on MRST if the brightness is nil (ie blanked)
 */
static int psb_lvds_i2c_set_brightness(struct drm_device *dev,
                    unsigned int level)
{
    struct drm_psb_private *dev_priv =
        (struct drm_psb_private *)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) {
        dev_dbg(dev->dev, "I2C set brightness.(command, value) (%d, %d)\n",
            dev_priv->lvds_bl->brightnesscmd,
            blc_i2c_brightness);
        return 0;
    }

    dev_err(dev->dev, "I2C transfer error\n");
    return -1;
}


static int psb_lvds_pwm_set_brightness(struct drm_device *dev, int level)
{
    struct drm_psb_private *dev_priv =
            (struct drm_psb_private *)dev->dev_private;

    u32 max_pwm_blc;
    u32 blc_pwm_duty_cycle;

    max_pwm_blc = psb_intel_lvds_get_max_backlight(dev);

    /*BLC_PWM_CTL Should be initiated while backlight device init*/
    BUG_ON(max_pwm_blc == 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));

        dev_info(dev->dev, "Backlight lvds set brightness %08x\n",
          (max_pwm_blc << PSB_BACKLIGHT_PWM_CTL_SHIFT) |
          (blc_pwm_duty_cycle));

    return 0;
}

/*
 * Set LVDS backlight level either by I2C or PWM
 */
void psb_intel_lvds_set_brightness(struct drm_device *dev, int level)
{
    struct drm_psb_private *dev_priv = dev->dev_private;

    dev_dbg(dev->dev, "backlight level is %d\n", level);

    if (!dev_priv->lvds_bl) {
        dev_err(dev->dev, "NO LVDS backlight info\n");
        return;
    }

    if (dev_priv->lvds_bl->type == BLC_I2C_TYPE)
        psb_lvds_i2c_set_brightness(dev, level);
    else
        psb_lvds_pwm_set_brightness(dev, level);
}

/*
 * Sets the backlight level.
 *
 * level: backlight level, from 0 to psb_intel_lvds_get_max_backlight().
 */
static void psb_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);
        blc_pwm_ctl &= ~BACKLIGHT_DUTY_CYCLE_MASK;
        REG_WRITE(BLC_PWM_CTL,
                (blc_pwm_ctl |
                (level << BACKLIGHT_DUTY_CYCLE_SHIFT)));
        dev_priv->regs.saveBLC_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));
    }
}

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

    if (!gma_power_begin(dev, true)) {
            dev_err(dev->dev, "set power, chip off!\n");
        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);

        psb_intel_lvds_set_backlight(dev,
                         mode_dev->backlight_duty_cycle);
    } else {
        psb_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 psb_intel_lvds_encoder_dpms(struct drm_encoder *encoder, int mode)
{
    struct drm_device *dev = encoder->dev;

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

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

static void psb_intel_lvds_save(struct drm_connector *connector)
{
    struct drm_device *dev = connector->dev;
    struct drm_psb_private *dev_priv =
        (struct drm_psb_private *)dev->dev_private;
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);
    struct psb_intel_lvds_priv *lvds_priv =
        (struct psb_intel_lvds_priv *)psb_intel_encoder->dev_priv;

    lvds_priv->savePP_ON = REG_READ(LVDSPP_ON);
    lvds_priv->savePP_OFF = REG_READ(LVDSPP_OFF);
    lvds_priv->saveLVDS = REG_READ(LVDS);
    lvds_priv->savePP_CONTROL = REG_READ(PP_CONTROL);
    lvds_priv->savePP_CYCLE = REG_READ(PP_CYCLE);
    /*lvds_priv->savePP_DIVISOR = REG_READ(PP_DIVISOR);*/
    lvds_priv->saveBLC_PWM_CTL = REG_READ(BLC_PWM_CTL);
    lvds_priv->savePFIT_CONTROL = REG_READ(PFIT_CONTROL);
    lvds_priv->savePFIT_PGM_RATIOS = REG_READ(PFIT_PGM_RATIOS);

    /*TODO: move backlight_duty_cycle to psb_intel_lvds_priv*/
    dev_priv->backlight_duty_cycle = (dev_priv->regs.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 =
        psb_intel_lvds_get_max_backlight(dev);

    dev_dbg(dev->dev, "(0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x)\n",
            lvds_priv->savePP_ON,
            lvds_priv->savePP_OFF,
            lvds_priv->saveLVDS,
            lvds_priv->savePP_CONTROL,
            lvds_priv->savePP_CYCLE,
            lvds_priv->saveBLC_PWM_CTL);
}

static void psb_intel_lvds_restore(struct drm_connector *connector)
{
    struct drm_device *dev = connector->dev;
    u32 pp_status;
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);
    struct psb_intel_lvds_priv *lvds_priv =
        (struct psb_intel_lvds_priv *)psb_intel_encoder->dev_priv;

    dev_dbg(dev->dev, "(0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x)\n",
            lvds_priv->savePP_ON,
            lvds_priv->savePP_OFF,
            lvds_priv->saveLVDS,
            lvds_priv->savePP_CONTROL,
            lvds_priv->savePP_CYCLE,
            lvds_priv->saveBLC_PWM_CTL);

    REG_WRITE(BLC_PWM_CTL, lvds_priv->saveBLC_PWM_CTL);
    REG_WRITE(PFIT_CONTROL, lvds_priv->savePFIT_CONTROL);
    REG_WRITE(PFIT_PGM_RATIOS, lvds_priv->savePFIT_PGM_RATIOS);
    REG_WRITE(LVDSPP_ON, lvds_priv->savePP_ON);
    REG_WRITE(LVDSPP_OFF, lvds_priv->savePP_OFF);
    /*REG_WRITE(PP_DIVISOR, lvds_priv->savePP_DIVISOR);*/
    REG_WRITE(PP_CYCLE, lvds_priv->savePP_CYCLE);
    REG_WRITE(PP_CONTROL, lvds_priv->savePP_CONTROL);
    REG_WRITE(LVDS, lvds_priv->saveLVDS);

    if (lvds_priv->savePP_CONTROL & POWER_TARGET_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);
    } else {
        REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) &
            ~POWER_TARGET_ON);
        do {
            pp_status = REG_READ(PP_STATUS);
        } while (pp_status & PP_ON);
    }
}

int psb_intel_lvds_mode_valid(struct drm_connector *connector,
                 struct drm_display_mode *mode)
{
    struct drm_psb_private *dev_priv = connector->dev->dev_private;
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);
    struct drm_display_mode *fixed_mode =
                    dev_priv->mode_dev.panel_fixed_mode;

    if (psb_intel_encoder->type == INTEL_OUTPUT_MIPI2)
        fixed_mode = dev_priv->mode_dev.panel_fixed_mode2;

    /* 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 psb_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 psb_intel_crtc *psb_intel_crtc =
                to_psb_intel_crtc(encoder->crtc);
    struct drm_encoder *tmp_encoder;
    struct drm_display_mode *panel_fixed_mode = mode_dev->panel_fixed_mode;
    struct psb_intel_encoder *psb_intel_encoder =
                        to_psb_intel_encoder(encoder);

    if (psb_intel_encoder->type == INTEL_OUTPUT_MIPI2)
        panel_fixed_mode = mode_dev->panel_fixed_mode2;

    /* PSB requires the LVDS is on pipe B, MRST has only one pipe anyway */
    if (!IS_MRST(dev) && psb_intel_crtc->pipe == 0) {
        printk(KERN_ERR "Can't support LVDS on pipe A\n");
        return false;
    }
    if (IS_MRST(dev) && psb_intel_crtc->pipe != 0) {
        printk(KERN_ERR "Must use 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 (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 psb_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);

    psb_intel_lvds_set_power(dev, false);

    gma_power_end(dev);
}

static void psb_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 =
            psb_intel_lvds_get_max_backlight(dev);

    psb_intel_lvds_set_power(dev, true);
}

static void psb_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;
    u32 pfit_control;

    /*
     * The LVDS pin pair will already have been turned on in the
     * psb_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 (dev_priv->lvds_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 psb_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 psb_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_mode_device *mode_dev = &dev_priv->mode_dev;
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);
    struct psb_intel_lvds_priv *lvds_priv = psb_intel_encoder->dev_priv;
    int ret = 0;

    if (!IS_MRST(dev))
        ret = psb_intel_ddc_get_modes(connector, &lvds_priv->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;
}

void psb_intel_lvds_destroy(struct drm_connector *connector)
{
    struct psb_intel_encoder *psb_intel_encoder =
                    psb_intel_attached_encoder(connector);
    struct psb_intel_lvds_priv *lvds_priv = psb_intel_encoder->dev_priv;

    if (lvds_priv->ddc_bus)
        psb_intel_i2c_destroy(lvds_priv->ddc_bus);
    drm_sysfs_connector_remove(connector);
    drm_connector_cleanup(connector);
    kfree(connector);
}

int psb_intel_lvds_set_property(struct drm_connector *connector,
                       struct drm_property *property,
                       uint64_t value)
{
    struct drm_encoder *encoder = connector->encoder;

    if (!encoder)
        return -1;

    if (!strcmp(property->name, "scaling mode")) {
        struct psb_intel_crtc *crtc =
                    to_psb_intel_crtc(encoder->crtc);
        uint64_t curval;

        if (!crtc)
            goto set_prop_error;

        switch (value) {
        case DRM_MODE_SCALE_FULLSCREEN:
            break;
        case DRM_MODE_SCALE_NO_SCALE:
            break;
        case DRM_MODE_SCALE_ASPECT:
            break;
        default:
            goto set_prop_error;
        }

        if (drm_connector_property_get_value(connector,
                             property,
                             &curval))
            goto set_prop_error;

        if (curval == value)
            goto set_prop_done;

        if (drm_connector_property_set_value(connector,
                            property,
                            value))
            goto set_prop_error;

        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))
                goto set_prop_error;
        }
    } else if (!strcmp(property->name, "backlight")) {
        if (drm_connector_property_set_value(connector,
                            property,
                            value))
            goto set_prop_error;
        else
                        gma_backlight_set(encoder->dev, value);
    } else if (!strcmp(property->name, "DPMS")) {
        struct drm_encoder_helper_funcs *hfuncs
                        = encoder->helper_private;
        hfuncs->dpms(encoder, value);
    }

set_prop_done:
    return 0;
set_prop_error:
    return -1;
}

static const struct drm_encoder_helper_funcs psb_intel_lvds_helper_funcs = {
    .dpms = psb_intel_lvds_encoder_dpms,
    .mode_fixup = psb_intel_lvds_mode_fixup,
    .prepare = psb_intel_lvds_prepare,
    .mode_set = psb_intel_lvds_mode_set,
    .commit = psb_intel_lvds_commit,
};

const struct drm_connector_helper_funcs
                psb_intel_lvds_connector_helper_funcs = {
    .get_modes = psb_intel_lvds_get_modes,
    .mode_valid = psb_intel_lvds_mode_valid,
    .best_encoder = psb_intel_best_encoder,
};

const struct drm_connector_funcs psb_intel_lvds_connector_funcs = {
    .dpms = drm_helper_connector_dpms,
    .save = psb_intel_lvds_save,
    .restore = psb_intel_lvds_restore,
    .detect = psb_intel_lvds_detect,
    .fill_modes = drm_helper_probe_single_connector_modes,
    .set_property = psb_intel_lvds_set_property,
    .destroy = psb_intel_lvds_destroy,
};


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

const struct drm_encoder_funcs psb_intel_lvds_enc_funcs = {
    .destroy = psb_intel_lvds_enc_destroy,
};



void psb_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 psb_intel_lvds_priv *lvds_priv;
    struct drm_connector *connector;
    struct drm_encoder *encoder;
    struct drm_display_mode *scan;  /* *modes, *bios_mode; */
    struct drm_crtc *crtc;
    struct drm_psb_private *dev_priv = dev->dev_private;
    u32 lvds;
    int pipe;

    psb_intel_encoder =
            kzalloc(sizeof(struct psb_intel_encoder), GFP_KERNEL);
    if (!psb_intel_encoder) {
        dev_err(dev->dev, "psb_intel_encoder allocation error\n");
        return;
    }

    psb_intel_connector =
        kzalloc(sizeof(struct psb_intel_connector), GFP_KERNEL);
    if (!psb_intel_connector) {
        dev_err(dev->dev, "psb_intel_connector allocation error\n");
        goto failed_encoder;
    }

    lvds_priv = kzalloc(sizeof(struct psb_intel_lvds_priv), GFP_KERNEL);
    if (!lvds_priv) {
        dev_err(dev->dev, "LVDS private allocation error\n");
        goto failed_connector;
    }

    psb_intel_encoder->dev_priv = lvds_priv;

    connector = &psb_intel_connector->base;
    encoder = &psb_intel_encoder->base;
    drm_connector_init(dev, connector,
               &psb_intel_lvds_connector_funcs,
               DRM_MODE_CONNECTOR_LVDS);

    drm_encoder_init(dev, encoder,
             &psb_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, &psb_intel_lvds_helper_funcs);
    drm_connector_helper_add(connector,
                 &psb_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
     */
    lvds_priv->i2c_bus = psb_intel_i2c_create(dev, GPIOB, "LVDSBLC_B");
    if (!lvds_priv->i2c_bus) {
        dev_printk(KERN_ERR,
            &dev->pdev->dev, "I2C bus registration failed.\n");
        goto failed_blc_i2c;
    }
    lvds_priv->i2c_bus->slave_addr = 0x2C;
    dev_priv->lvds_i2c_bus =  lvds_priv->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. */
    lvds_priv->ddc_bus = psb_intel_i2c_create(dev, GPIOC, "LVDSDDC_C");
    if (!lvds_priv->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, &lvds_priv->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 (mode_dev->vbt_mode)
        mode_dev->panel_fixed_mode =
            drm_mode_duplicate(dev, mode_dev->vbt_mode);

    if (!mode_dev->panel_fixed_mode)
        if (dev_priv->lfp_lvds_vbt_mode)
            mode_dev->panel_fixed_mode =
                drm_mode_duplicate(dev,
                    dev_priv->lfp_lvds_vbt_mode);

    /*
     * 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 =
            psb_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) {
        dev_err(dev->dev, "Found no modes on the lvds, ignoring the LVDS\n");
        goto failed_find;
    }

    /*
     * Blacklist machines with BIOSes that list an LVDS panel without
     * actually having one.
     */
out:
    drm_sysfs_connector_add(connector);
    return;

failed_find:
    if (lvds_priv->ddc_bus)
        psb_intel_i2c_destroy(lvds_priv->ddc_bus);
failed_ddc:
    if (lvds_priv->i2c_bus)
        psb_intel_i2c_destroy(lvds_priv->i2c_bus);
failed_blc_i2c:
    drm_encoder_cleanup(encoder);
    drm_connector_cleanup(connector);
failed_connector:
    kfree(psb_intel_connector);
failed_encoder:
    kfree(psb_intel_encoder);
}