/**
 * @file
 * @section AUTHORS
 *
 *  Copyright IBM, Corp. 2005-2006
 *  Copyright Red Hat, Inc. 2006-2008
 *
 *  Authors:
 *       Anthony Liguori <aliguori@us.ibm.com>,
 *       Markus Armbruster <armbru@redhat.com>,
 *       Daniel P. Berrange <berrange@redhat.com>,
 *       Pat Campbell <plc@novell.com>,
 *       Gerd Hoffmann <kraxel@redhat.com>
 *       Eamon Walsh <ewalsh@tycho.nsa.gov>
 *
 * @section LICENSE
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; under version 2 of the License.
 *
 *  This program is distributed in the hope that 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * @section DESCRIPTION
 *
 * This is the stock framebuffer and input backend code from QEMU,
 * modified to call Linpicker instead of QEMU functions.
 *
 * This is the code for linpicker-monitor, which is responsible for setting
 * up the framebuffer and input device backends in XenStore.  This code
 * acutally only handles XenStore writes during frontend state transitions;
 * the initial setup is done using functions from libxenlight.  No actual
 * servicing of the devices are done here, that is linpicker-server's job.
 */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>

#include <linux/fb.h>

#include "xen_backend.h"
#include "xen_linpicker.h"
#include "display.h"

static int width, height;

int xenfb_monitor_init(void)
{
    struct fb_var_screeninfo fvs;
    int rc, fd;

    /* XXX test this failure case */
    width = 800;
    height = 600;

    fd = open("/dev/fb0", O_RDONLY);
    if (fd < 0)
	return -1;

    rc = ioctl(fd, FBIOGET_VSCREENINFO, &fvs);
    if (rc == 0) {
	width = fvs.xres_virtual;
	height = fvs.yres_virtual - SECLABEL_HEIGHT;
    }

    close(fd);
    return 0;
}

/* -------------------------------------------------------------------- */

static int input_init(struct XenDevice *xendev)
{
    xenstore_write_be_int(xendev, "feature-abs-pointer", 1);
    xenstore_write_be_int(xendev, "width", width);
    xenstore_write_be_int(xendev, "height", height);
    return 0;
}

/* -------------------------------------------------------------------- */

static int fb_init(struct XenDevice *xendev)
{
#ifdef XENFB_TYPE_RESIZE
    xenstore_write_be_int(xendev, "feature-resize", 1);
#endif
    xenstore_write_be_int(xendev, "feature-grants", 1);
    xenstore_write_be_int(xendev, "width", width);
    xenstore_write_be_int(xendev, "height", height);

    return 0;
}

static int fb_initialise(struct XenDevice *xendev)
{
    int videoram, update;

    if (xenstore_read_fe_int(xendev, "videoram", &videoram) == -1)
	videoram = 0;
    if (xenstore_read_fe_int(xendev, "feature-update", &update) == -1)
	update = 0;
    if (update)
	xenstore_write_be_int(xendev, "request-update", 1);

    XEN_BE_LOG(xendev, 1, "feature-update=%d, videoram=%d\n",
		  update, videoram);
    return 0;
}

static void fb_frontend_changed(struct XenDevice *xendev, const char *node)
{
    struct XenFB *fb = (struct XenFB *)xendev;

    /*
     * Set state to Connected *again* once the frontend switched
     * to connected.  We must trigger the watch a second time to
     * workaround a frontend bug.
     */
    if (fb->bug_trigger == 0 && strcmp(node, "state") == 0 &&
        xendev->fe_state == XenbusStateConnected &&
        xendev->be_state == XenbusStateConnected) {
        XEN_BE_LOG(xendev, 2, "re-trigger connected (frontend bug)\n");
        xen_be_set_state(xendev, XenbusStateConnected);
        fb->bug_trigger = 1; /* only once */
    }
}

static void fb_disconnect(struct XenDevice *xendev)
{
    struct XenFB *fb = (struct XenFB *)xendev;

    fb->feature_update = 0;
    fb->bug_trigger    = 0;
}

/* -------------------------------------------------------------------- */

struct XenDevOps xen_kbdmouse_ops = {
    .size       = sizeof(struct XenInput),
    .init       = input_init,
};

struct XenDevOps xen_framebuffer_ops = {
    .size       = sizeof(struct XenFB),
    .init       = fb_init,
    .initialise = fb_initialise,
    .disconnect = fb_disconnect,
    .frontend_changed = fb_frontend_changed,
};