olpc_dcon.c

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/*
 * Mainly by David Woodhouse, somewhat modified by Jordan Crouse
 *
 * Copyright © 2006-2007  Red Hat, Inc.
 * Copyright © 2006-2007  Advanced Micro Devices, Inc.
 * Copyright © 2009       VIA Technology, Inc.
 * Copyright (c) 2010-2011  Andres Salomon <[email protected]>
 *
 * This program is free software.  You can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/fb.h>
#include <linux/console.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/backlight.h>
#include <linux/device.h>
#include <linux/uaccess.h>
#include <linux/ctype.h>
#include <linux/reboot.h>
#include <linux/olpc-ec.h>
#include <asm/tsc.h>
#include <asm/olpc.h>

#include "olpc_dcon.h"

/* Module definitions */

static ushort resumeline = 898;
module_param(resumeline, ushort, 0444);

/* Default off since it doesn't work on DCON ASIC in B-test OLPC board */
static int useaa = 1;
module_param(useaa, int, 0444);

static struct dcon_platform_data *pdata;

/* I2C structures */

/* Platform devices */
static struct platform_device *dcon_device;

static DECLARE_WAIT_QUEUE_HEAD(dcon_wait_queue);

static unsigned short normal_i2c[] = { 0x0d, I2C_CLIENT_END };

static s32 dcon_write(struct dcon_priv *dcon, u8 reg, u16 val)
{
    return i2c_smbus_write_word_data(dcon->client, reg, val);
}

static s32 dcon_read(struct dcon_priv *dcon, u8 reg)
{
    return i2c_smbus_read_word_data(dcon->client, reg);
}

/* ===== API functions - these are called by a variety of users ==== */

static int dcon_hw_init(struct dcon_priv *dcon, int is_init)
{
    uint16_t ver;
    int rc = 0;

    ver = dcon_read(dcon, DCON_REG_ID);
    if ((ver >> 8) != 0xDC) {
        pr_err("DCON ID not 0xDCxx: 0x%04x instead.\n", ver);
        rc = -ENXIO;
        goto err;
    }

    if (is_init) {
        pr_info("Discovered DCON version %x\n", ver & 0xFF);
        rc = pdata->init(dcon);
        if (rc != 0) {
            pr_err("Unable to init.\n");
            goto err;
        }
    }

    if (ver < 0xdc02) {
        dev_err(&dcon->client->dev,
                "DCON v1 is unsupported, giving up..\n");
        rc = -ENODEV;
        goto err;
    }

    /* SDRAM setup/hold time */
    dcon_write(dcon, 0x3a, 0xc040);
    dcon_write(dcon, 0x41, 0x0000);
    dcon_write(dcon, 0x41, 0x0101);
    dcon_write(dcon, 0x42, 0x0101);

    /* Colour swizzle, AA, no passthrough, backlight */
    if (is_init) {
        dcon->disp_mode = MODE_PASSTHRU | MODE_BL_ENABLE |
                MODE_CSWIZZLE;
        if (useaa)
            dcon->disp_mode |= MODE_COL_AA;
    }
    dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);


    /* Set the scanline to interrupt on during resume */
    dcon_write(dcon, DCON_REG_SCAN_INT, resumeline);

err:
    return rc;
}

/*
 * The smbus doesn't always come back due to what is believed to be
 * hardware (power rail) bugs.  For older models where this is known to
 * occur, our solution is to attempt to wait for the bus to stabilize;
 * if it doesn't happen, cut power to the dcon, repower it, and wait
 * for the bus to stabilize.  Rinse, repeat until we have a working
 * smbus.  For newer models, we simply BUG(); we want to know if this
 * still happens despite the power fixes that have been made!
 */
static int dcon_bus_stabilize(struct dcon_priv *dcon, int is_powered_down)
{
    unsigned long timeout;
    int x;

power_up:
    if (is_powered_down) {
        x = 1;
        x = olpc_ec_cmd(0x26, (unsigned char *)&x, 1, NULL, 0);
        if (x) {
            pr_warn("unable to force dcon to power up: %d!\n", x);
            return x;
        }
        msleep(10); /* we'll be conservative */
    }

    pdata->bus_stabilize_wiggle();

    for (x = -1, timeout = 50; timeout && x < 0; timeout--) {
        msleep(1);
        x = dcon_read(dcon, DCON_REG_ID);
    }
    if (x < 0) {
        pr_err("unable to stabilize dcon's smbus, reasserting power and praying.\n");
        BUG_ON(olpc_board_at_least(olpc_board(0xc2)));
        x = 0;
        olpc_ec_cmd(0x26, (unsigned char *)&x, 1, NULL, 0);
        msleep(100);
        is_powered_down = 1;
        goto power_up;  /* argh, stupid hardware.. */
    }

    if (is_powered_down)
        return dcon_hw_init(dcon, 0);
    return 0;
}

static void dcon_set_backlight(struct dcon_priv *dcon, u8 level)
{
    dcon->bl_val = level;
    dcon_write(dcon, DCON_REG_BRIGHT, dcon->bl_val);

    /* Purposely turn off the backlight when we go to level 0 */
    if (dcon->bl_val == 0) {
        dcon->disp_mode &= ~MODE_BL_ENABLE;
        dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);
    } else if (!(dcon->disp_mode & MODE_BL_ENABLE)) {
        dcon->disp_mode |= MODE_BL_ENABLE;
        dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);
    }
}

/* Set the output type to either color or mono */
static int dcon_set_mono_mode(struct dcon_priv *dcon, bool enable_mono)
{
    if (dcon->mono == enable_mono)
        return 0;

    dcon->mono = enable_mono;

    if (enable_mono) {
        dcon->disp_mode &= ~(MODE_CSWIZZLE | MODE_COL_AA);
        dcon->disp_mode |= MODE_MONO_LUMA;
    } else {
        dcon->disp_mode &= ~(MODE_MONO_LUMA);
        dcon->disp_mode |= MODE_CSWIZZLE;
        if (useaa)
            dcon->disp_mode |= MODE_COL_AA;
    }

    dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode);
    return 0;
}

/* For now, this will be really stupid - we need to address how
 * DCONLOAD works in a sleep and account for it accordingly
 */

static void dcon_sleep(struct dcon_priv *dcon, bool sleep)
{
    int x;

    /* Turn off the backlight and put the DCON to sleep */

    if (dcon->asleep == sleep)
        return;

    if (!olpc_board_at_least(olpc_board(0xc2)))
        return;

    if (sleep) {
        x = 0;
        x = olpc_ec_cmd(0x26, (unsigned char *)&x, 1, NULL, 0);
        if (x)
            pr_warn("unable to force dcon to power down: %d!\n", x);
        else
            dcon->asleep = sleep;
    } else {
        /* Only re-enable the backlight if the backlight value is set */
        if (dcon->bl_val != 0)
            dcon->disp_mode |= MODE_BL_ENABLE;
        x = dcon_bus_stabilize(dcon, 1);
        if (x)
            pr_warn("unable to reinit dcon hardware: %d!\n", x);
        else
            dcon->asleep = sleep;

        /* Restore backlight */
        dcon_set_backlight(dcon, dcon->bl_val);
    }

    /* We should turn off some stuff in the framebuffer - but what? */
}

/* the DCON seems to get confused if we change DCONLOAD too
 * frequently -- i.e., approximately faster than frame time.
 * normally we don't change it this fast, so in general we won't
 * delay here.
 */
static void dcon_load_holdoff(struct dcon_priv *dcon)
{
    struct timespec delta_t, now;
    while (1) {
        getnstimeofday(&now);
        delta_t = timespec_sub(now, dcon->load_time);
        if (delta_t.tv_sec != 0 ||
            delta_t.tv_nsec > NSEC_PER_MSEC * 20) {
            break;
        }
        mdelay(4);
    }
}

static bool dcon_blank_fb(struct dcon_priv *dcon, bool blank)
{
    int err;

    if (!lock_fb_info(dcon->fbinfo)) {
        dev_err(&dcon->client->dev, "unable to lock framebuffer\n");
        return false;
    }
    console_lock();
    dcon->ignore_fb_events = true;
    err = fb_blank(dcon->fbinfo,
            blank ? FB_BLANK_POWERDOWN : FB_BLANK_UNBLANK);
    dcon->ignore_fb_events = false;
    console_unlock();
    unlock_fb_info(dcon->fbinfo);

    if (err) {
        dev_err(&dcon->client->dev, "couldn't %sblank framebuffer\n",
                blank ? "" : "un");
        return false;
    }
    return true;
}

/* Set the source of the display (CPU or DCON) */
static void dcon_source_switch(struct work_struct *work)
{
    struct dcon_priv *dcon = container_of(work, struct dcon_priv,
            switch_source);
    DECLARE_WAITQUEUE(wait, current);
    int source = dcon->pending_src;

    if (dcon->curr_src == source)
        return;

    dcon_load_holdoff(dcon);

    dcon->switched = false;

    switch (source) {
    case DCON_SOURCE_CPU:
        pr_info("dcon_source_switch to CPU\n");
        /* Enable the scanline interrupt bit */
        if (dcon_write(dcon, DCON_REG_MODE,
                dcon->disp_mode | MODE_SCAN_INT))
            pr_err("couldn't enable scanline interrupt!\n");
        else {
            /* Wait up to one second for the scanline interrupt */
            wait_event_timeout(dcon_wait_queue,
                       dcon->switched == true, HZ);
        }

        if (!dcon->switched)
            pr_err("Timeout entering CPU mode; expect a screen glitch.\n");

        /* Turn off the scanline interrupt */
        if (dcon_write(dcon, DCON_REG_MODE, dcon->disp_mode))
            pr_err("couldn't disable scanline interrupt!\n");

        /*
         * Ideally we'd like to disable interrupts here so that the
         * fb unblanking and DCON turn on happen at a known time value;
         * however, we can't do that right now with fb_blank
         * messing with semaphores.
         *
         * For now, we just hope..
         */
        if (!dcon_blank_fb(dcon, false)) {
            pr_err("Failed to enter CPU mode\n");
            dcon->pending_src = DCON_SOURCE_DCON;
            return;
        }

        /* And turn off the DCON */
        pdata->set_dconload(1);
        getnstimeofday(&dcon->load_time);

        pr_info("The CPU has control\n");
        break;
    case DCON_SOURCE_DCON:
    {
        int t;
        struct timespec delta_t;

        pr_info("dcon_source_switch to DCON\n");

        add_wait_queue(&dcon_wait_queue, &wait);
        set_current_state(TASK_UNINTERRUPTIBLE);

        /* Clear DCONLOAD - this implies that the DCON is in control */
        pdata->set_dconload(0);
        getnstimeofday(&dcon->load_time);

        t = schedule_timeout(HZ/2);
        remove_wait_queue(&dcon_wait_queue, &wait);
        set_current_state(TASK_RUNNING);

        if (!dcon->switched) {
            pr_err("Timeout entering DCON mode; expect a screen glitch.\n");
        } else {
            /* sometimes the DCON doesn't follow its own rules,
             * and doesn't wait for two vsync pulses before
             * ack'ing the frame load with an IRQ.  the result
             * is that the display shows the *previously*
             * loaded frame.  we can detect this by looking at
             * the time between asserting DCONLOAD and the IRQ --
             * if it's less than 20msec, then the DCON couldn't
             * have seen two VSYNC pulses.  in that case we
             * deassert and reassert, and hope for the best.
             * see http://dev.laptop.org/ticket/9664
             */
            delta_t = timespec_sub(dcon->irq_time, dcon->load_time);
            if (dcon->switched && delta_t.tv_sec == 0 &&
                    delta_t.tv_nsec < NSEC_PER_MSEC * 20) {
                pr_err("missed loading, retrying\n");
                pdata->set_dconload(1);
                mdelay(41);
                pdata->set_dconload(0);
                getnstimeofday(&dcon->load_time);
                mdelay(41);
            }
        }

        dcon_blank_fb(dcon, true);
        pr_info("The DCON has control\n");
        break;
    }
    default:
        BUG();
    }

    dcon->curr_src = source;
}

static void dcon_set_source(struct dcon_priv *dcon, int arg)
{
    if (dcon->pending_src == arg)
        return;

    dcon->pending_src = arg;

    if ((dcon->curr_src != arg) && !work_pending(&dcon->switch_source))
        schedule_work(&dcon->switch_source);
}

static void dcon_set_source_sync(struct dcon_priv *dcon, int arg)
{
    dcon_set_source(dcon, arg);
    flush_scheduled_work();
}

static ssize_t dcon_mode_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct dcon_priv *dcon = dev_get_drvdata(dev);
    return sprintf(buf, "%4.4X\n", dcon->disp_mode);
}

static ssize_t dcon_sleep_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{

    struct dcon_priv *dcon = dev_get_drvdata(dev);
    return sprintf(buf, "%d\n", dcon->asleep);
}

static ssize_t dcon_freeze_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct dcon_priv *dcon = dev_get_drvdata(dev);
    return sprintf(buf, "%d\n", dcon->curr_src == DCON_SOURCE_DCON ? 1 : 0);
}

static ssize_t dcon_mono_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    struct dcon_priv *dcon = dev_get_drvdata(dev);
    return sprintf(buf, "%d\n", dcon->mono);
}

static ssize_t dcon_resumeline_show(struct device *dev,
    struct device_attribute *attr, char *buf)
{
    return sprintf(buf, "%d\n", resumeline);
}

static ssize_t dcon_mono_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    unsigned long enable_mono;
    int rc;

    rc = kstrtoul(buf, 10, &enable_mono);
    if (rc)
        return rc;

    dcon_set_mono_mode(dev_get_drvdata(dev), enable_mono ? true : false);

    return count;
}

static ssize_t dcon_freeze_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    struct dcon_priv *dcon = dev_get_drvdata(dev);
    unsigned long output;
    int ret;

    ret = kstrtoul(buf, 10, &output);
    if (ret)
        return ret;

    pr_info("dcon_freeze_store: %lu\n", output);

    switch (output) {
    case 0:
        dcon_set_source(dcon, DCON_SOURCE_CPU);
        break;
    case 1:
        dcon_set_source_sync(dcon, DCON_SOURCE_DCON);
        break;
    case 2:  /* normally unused */
        dcon_set_source(dcon, DCON_SOURCE_DCON);
        break;
    default:
        return -EINVAL;
    }

    return count;
}

static ssize_t dcon_resumeline_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    unsigned short rl;
    int rc;

    rc = kstrtou16(buf, 10, &rl);
    if (rc)
        return rc;

    resumeline = rl;
    dcon_write(dev_get_drvdata(dev), DCON_REG_SCAN_INT, resumeline);

    return count;
}

static ssize_t dcon_sleep_store(struct device *dev,
    struct device_attribute *attr, const char *buf, size_t count)
{
    unsigned long output;
    int ret;

    ret = kstrtoul(buf, 10, &output);
    if (ret)
        return ret;

    dcon_sleep(dev_get_drvdata(dev), output ? true : false);
    return count;
}

static struct device_attribute dcon_device_files[] = {
    __ATTR(mode, 0444, dcon_mode_show, NULL),
    __ATTR(sleep, 0644, dcon_sleep_show, dcon_sleep_store),
    __ATTR(freeze, 0644, dcon_freeze_show, dcon_freeze_store),
    __ATTR(monochrome, 0644, dcon_mono_show, dcon_mono_store),
    __ATTR(resumeline, 0644, dcon_resumeline_show, dcon_resumeline_store),
};

static int dcon_bl_update(struct backlight_device *dev)
{
    struct dcon_priv *dcon = bl_get_data(dev);
    u8 level = dev->props.brightness & 0x0F;

    if (dev->props.power != FB_BLANK_UNBLANK)
        level = 0;

    if (level != dcon->bl_val)
        dcon_set_backlight(dcon, level);

    return 0;
}

static int dcon_bl_get(struct backlight_device *dev)
{
    struct dcon_priv *dcon = bl_get_data(dev);
    return dcon->bl_val;
}

static const struct backlight_ops dcon_bl_ops = {
    .update_status = dcon_bl_update,
    .get_brightness = dcon_bl_get,
};

static struct backlight_properties dcon_bl_props = {
    .max_brightness = 15,
    .type = BACKLIGHT_RAW,
    .power = FB_BLANK_UNBLANK,
};

static int dcon_reboot_notify(struct notifier_block *nb,
                  unsigned long foo, void *bar)
{
    struct dcon_priv *dcon = container_of(nb, struct dcon_priv, reboot_nb);

    if (!dcon || !dcon->client)
        return 0;

    /* Turn off the DCON. Entirely. */
    dcon_write(dcon, DCON_REG_MODE, 0x39);
    dcon_write(dcon, DCON_REG_MODE, 0x32);
    return 0;
}

static int unfreeze_on_panic(struct notifier_block *nb,
                 unsigned long e, void *p)
{
    pdata->set_dconload(1);
    return NOTIFY_DONE;
}

static struct notifier_block dcon_panic_nb = {
    .notifier_call = unfreeze_on_panic,
};

/*
 * When the framebuffer sleeps due to external sources (e.g. user idle), power
 * down the DCON as well.  Power it back up when the fb comes back to life.
 */
static int dcon_fb_notifier(struct notifier_block *self,
                unsigned long event, void *data)
{
    struct fb_event *evdata = data;
    struct dcon_priv *dcon = container_of(self, struct dcon_priv,
            fbevent_nb);
    int *blank = (int *)evdata->data;
    if (((event != FB_EVENT_BLANK) && (event != FB_EVENT_CONBLANK)) ||
            dcon->ignore_fb_events)
        return 0;
    dcon_sleep(dcon, *blank ? true : false);
    return 0;
}

static int dcon_detect(struct i2c_client *client, struct i2c_board_info *info)
{
    strlcpy(info->type, "olpc_dcon", I2C_NAME_SIZE);

    return 0;
}

static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
    struct dcon_priv *dcon;
    int rc, i, j;

    if (!pdata)
        return -ENXIO;

    dcon = kzalloc(sizeof(*dcon), GFP_KERNEL);
    if (!dcon)
        return -ENOMEM;

    dcon->client = client;
    INIT_WORK(&dcon->switch_source, dcon_source_switch);
    dcon->reboot_nb.notifier_call = dcon_reboot_notify;
    dcon->reboot_nb.priority = -1;
    dcon->fbevent_nb.notifier_call = dcon_fb_notifier;

    i2c_set_clientdata(client, dcon);

    if (num_registered_fb < 1) {
        dev_err(&client->dev, "DCON driver requires a registered fb\n");
        rc = -EIO;
        goto einit;
    }
    dcon->fbinfo = registered_fb[0];

    rc = dcon_hw_init(dcon, 1);
    if (rc)
        goto einit;

    /* Add the DCON device */

    dcon_device = platform_device_alloc("dcon", -1);

    if (dcon_device == NULL) {
        pr_err("Unable to create the DCON device\n");
        rc = -ENOMEM;
        goto eirq;
    }
    rc = platform_device_add(dcon_device);
    platform_set_drvdata(dcon_device, dcon);

    if (rc) {
        pr_err("Unable to add the DCON device\n");
        goto edev;
    }

    for (i = 0; i < ARRAY_SIZE(dcon_device_files); i++) {
        rc = device_create_file(&dcon_device->dev,
                    &dcon_device_files[i]);
        if (rc) {
            dev_err(&dcon_device->dev, "Cannot create sysfs file\n");
            goto ecreate;
        }
    }

    dcon->bl_val = dcon_read(dcon, DCON_REG_BRIGHT) & 0x0F;

    /* Add the backlight device for the DCON */
    dcon_bl_props.brightness = dcon->bl_val;
    dcon->bl_dev = backlight_device_register("dcon-bl", &dcon_device->dev,
        dcon, &dcon_bl_ops, &dcon_bl_props);
    if (IS_ERR(dcon->bl_dev)) {
        dev_err(&client->dev, "cannot register backlight dev (%ld)\n",
                PTR_ERR(dcon->bl_dev));
        dcon->bl_dev = NULL;
    }

    register_reboot_notifier(&dcon->reboot_nb);
    atomic_notifier_chain_register(&panic_notifier_list, &dcon_panic_nb);
    fb_register_client(&dcon->fbevent_nb);

    return 0;

 ecreate:
    for (j = 0; j < i; j++)
        device_remove_file(&dcon_device->dev, &dcon_device_files[j]);
 edev:
    platform_device_unregister(dcon_device);
    dcon_device = NULL;
 eirq:
    free_irq(DCON_IRQ, dcon);
 einit:
    kfree(dcon);
    return rc;
}

static int dcon_remove(struct i2c_client *client)
{
    struct dcon_priv *dcon = i2c_get_clientdata(client);

    fb_unregister_client(&dcon->fbevent_nb);
    unregister_reboot_notifier(&dcon->reboot_nb);
    atomic_notifier_chain_unregister(&panic_notifier_list, &dcon_panic_nb);

    free_irq(DCON_IRQ, dcon);

    if (dcon->bl_dev)
        backlight_device_unregister(dcon->bl_dev);

    if (dcon_device != NULL)
        platform_device_unregister(dcon_device);
    cancel_work_sync(&dcon->switch_source);

    kfree(dcon);

    return 0;
}

#ifdef CONFIG_PM
static int dcon_suspend(struct i2c_client *client, pm_message_t state)
{
    struct dcon_priv *dcon = i2c_get_clientdata(client);

    if (!dcon->asleep) {
        /* Set up the DCON to have the source */
        dcon_set_source_sync(dcon, DCON_SOURCE_DCON);
    }

    return 0;
}

static int dcon_resume(struct i2c_client *client)
{
    struct dcon_priv *dcon = i2c_get_clientdata(client);

    if (!dcon->asleep) {
        dcon_bus_stabilize(dcon, 0);
        dcon_set_source(dcon, DCON_SOURCE_CPU);
    }

    return 0;
}

#endif


irqreturn_t dcon_interrupt(int irq, void *id)
{
    struct dcon_priv *dcon = id;
    u8 status;

    if (pdata->read_status(&status))
        return IRQ_NONE;

    switch (status & 3) {
    case 3:
        pr_debug("DCONLOAD_MISSED interrupt\n");
        break;

    case 2: /* switch to DCON mode */
    case 1: /* switch to CPU mode */
        dcon->switched = true;
        getnstimeofday(&dcon->irq_time);
        wake_up(&dcon_wait_queue);
        break;

    case 0:
        /* workaround resume case:  the DCON (on 1.5) doesn't
         * ever assert status 0x01 when switching to CPU mode
         * during resume.  this is because DCONLOAD is de-asserted
         * _immediately_ upon exiting S3, so the actual release
         * of the DCON happened long before this point.
         * see http://dev.laptop.org/ticket/9869
         */
        if (dcon->curr_src != dcon->pending_src && !dcon->switched) {
            dcon->switched = true;
            getnstimeofday(&dcon->irq_time);
            wake_up(&dcon_wait_queue);
            pr_debug("switching w/ status 0/0\n");
        } else {
            pr_debug("scanline interrupt w/CPU\n");
        }
    }

    return IRQ_HANDLED;
}

static const struct i2c_device_id dcon_idtable[] = {
    { "olpc_dcon",  0 },
    { }
};

MODULE_DEVICE_TABLE(i2c, dcon_idtable);

struct i2c_driver dcon_driver = {
    .driver = {
        .name   = "olpc_dcon",
    },
    .class = I2C_CLASS_DDC | I2C_CLASS_HWMON,
    .id_table = dcon_idtable,
    .probe = dcon_probe,
    .remove = __devexit_p(dcon_remove),
    .detect = dcon_detect,
    .address_list = normal_i2c,
#ifdef CONFIG_PM
    .suspend = dcon_suspend,
    .resume = dcon_resume,
#endif
};

static int __init olpc_dcon_init(void)
{
#ifdef CONFIG_FB_OLPC_DCON_1_5
    /* XO-1.5 */
    if (olpc_board_at_least(olpc_board(0xd0)))
        pdata = &dcon_pdata_xo_1_5;
#endif
#ifdef CONFIG_FB_OLPC_DCON_1
    if (!pdata)
        pdata = &dcon_pdata_xo_1;
#endif

    return i2c_add_driver(&dcon_driver);
}

static void __exit olpc_dcon_exit(void)
{
    i2c_del_driver(&dcon_driver);
}

module_init(olpc_dcon_init);
module_exit(olpc_dcon_exit);

MODULE_LICENSE("GPL");