/*
 * drivers/gpu/drm/omapdrm/omap_drv.c
 *
 * Copyright (C) 2011 Texas Instruments
 * Author: Rob Clark <rob@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include "omap_drv.h"

#include "drm_crtc_helper.h"
#include "drm_fb_helper.h"
#include "omap_dmm_tiler.h"

#define DRIVER_NAME             MODULE_NAME
#define DRIVER_DESC             "OMAP DRM"
#define DRIVER_DATE             "20110917"
#define DRIVER_MAJOR            1
#define DRIVER_MINOR            0
#define DRIVER_PATCHLEVEL       0

static int num_crtc = CONFIG_DRM_OMAP_NUM_CRTCS;

MODULE_PARM_DESC(num_crtc, "Number of overlays to use as CRTCs");
module_param(num_crtc, int, 0600);

/*
 * mode config funcs
 */

/* Notes about mapping DSS and DRM entities:
 *    CRTC:        overlay
 *    encoder:     manager.. with some extension to allow one primary CRTC
 *                 and zero or more video CRTC's to be mapped to one encoder?
 *    connector:   dssdev.. manager can be attached/detached from different
 *                 devices
 */

static void omap_fb_output_poll_changed(struct drm_device *dev)
{
        struct omap_drm_private *priv = dev->dev_private;
        DBG("dev=%p", dev);
        if (priv->fbdev)
                drm_fb_helper_hotplug_event(priv->fbdev);
}

static const struct drm_mode_config_funcs omap_mode_config_funcs = {
        .fb_create = omap_framebuffer_create,
        .output_poll_changed = omap_fb_output_poll_changed,
};

static int get_connector_type(struct omap_dss_device *dssdev)
{
        switch (dssdev->type) {
        case OMAP_DISPLAY_TYPE_HDMI:
                return DRM_MODE_CONNECTOR_HDMIA;
        case OMAP_DISPLAY_TYPE_DVI:
                return DRM_MODE_CONNECTOR_DVID;
        default:
                return DRM_MODE_CONNECTOR_Unknown;
        }
}

static bool channel_used(struct drm_device *dev, enum omap_channel channel)
{
        struct omap_drm_private *priv = dev->dev_private;
        int i;

        for (i = 0; i < priv->num_crtcs; i++) {
                struct drm_crtc *crtc = priv->crtcs[i];

                if (omap_crtc_channel(crtc) == channel)
                        return true;
        }

        return false;
}
static void omap_disconnect_dssdevs(void)
{
        struct omap_dss_device *dssdev = NULL;

        for_each_dss_dev(dssdev)
                dssdev->driver->disconnect(dssdev);
}

static int omap_connect_dssdevs(void)
{
        int r;
        struct omap_dss_device *dssdev = NULL;
        bool no_displays = true;

        for_each_dss_dev(dssdev) {
                r = dssdev->driver->connect(dssdev);
                if (r == -EPROBE_DEFER) {
                        omap_dss_put_device(dssdev);
                        goto cleanup;
                } else if (r) {
                        dev_warn(dssdev->dev, "could not connect display: %s\n",
                                dssdev->name);
                } else {
                        no_displays = false;
                }
        }

        if (no_displays)
                return -EPROBE_DEFER;

        return 0;

cleanup:
        /*
         * if we are deferring probe, we disconnect the devices we previously
         * connected
         */
        omap_disconnect_dssdevs();

        return r;
}

static int omap_modeset_create_crtc(struct drm_device *dev, int id,
                                    enum omap_channel channel)
{
        struct omap_drm_private *priv = dev->dev_private;
        struct drm_plane *plane;
        struct drm_crtc *crtc;

        plane = omap_plane_init(dev, id, DRM_PLANE_TYPE_PRIMARY);
        if (IS_ERR(plane))
                return PTR_ERR(plane);

        crtc = omap_crtc_init(dev, plane, channel, id);

        BUG_ON(priv->num_crtcs >= ARRAY_SIZE(priv->crtcs));
        priv->crtcs[id] = crtc;
        priv->num_crtcs++;

        priv->planes[id] = plane;
        priv->num_planes++;

        return 0;
}

static int omap_modeset_init(struct drm_device *dev)
{
        struct omap_drm_private *priv = dev->dev_private;
        struct omap_dss_device *dssdev = NULL;
        int num_ovls = dss_feat_get_num_ovls();
        int num_mgrs = dss_feat_get_num_mgrs();
        int num_crtcs;
        int i, id = 0;
        int ret;

        drm_mode_config_init(dev);

        omap_drm_irq_install(dev);

        /*
         * We usually don't want to create a CRTC for each manager, at least
         * not until we have a way to expose private planes to userspace.
         * Otherwise there would not be enough video pipes left for drm planes.
         * We use the num_crtc argument to limit the number of crtcs we create.
         */
        num_crtcs = min3(num_crtc, num_mgrs, num_ovls);

        dssdev = NULL;

        for_each_dss_dev(dssdev) {
                struct drm_connector *connector;
                struct drm_encoder *encoder;
                enum omap_channel channel;
                struct omap_overlay_manager *mgr;

                if (!omapdss_device_is_connected(dssdev))
                        continue;

                encoder = omap_encoder_init(dev, dssdev);

                if (!encoder) {
                        dev_err(dev->dev, "could not create encoder: %s\n",
                                        dssdev->name);
                        return -ENOMEM;
                }

                connector = omap_connector_init(dev,
                                get_connector_type(dssdev), dssdev, encoder);

                if (!connector) {
                        dev_err(dev->dev, "could not create connector: %s\n",
                                        dssdev->name);
                        return -ENOMEM;
                }

                BUG_ON(priv->num_encoders >= ARRAY_SIZE(priv->encoders));
                BUG_ON(priv->num_connectors >= ARRAY_SIZE(priv->connectors));

                priv->encoders[priv->num_encoders++] = encoder;
                priv->connectors[priv->num_connectors++] = connector;

                drm_mode_connector_attach_encoder(connector, encoder);

                /*
                 * if we have reached the limit of the crtcs we are allowed to
                 * create, let's not try to look for a crtc for this
                 * panel/encoder and onwards, we will, of course, populate the
                 * the possible_crtcs field for all the encoders with the final
                 * set of crtcs we create
                 */
                if (id == num_crtcs)
                        continue;

                /*
                 * get the recommended DISPC channel for this encoder. For now,
                 * we only try to get create a crtc out of the recommended, the
                 * other possible channels to which the encoder can connect are
                 * not considered.
                 */

                mgr = omapdss_find_mgr_from_display(dssdev);
                channel = mgr->id;
                /*
                 * if this channel hasn't already been taken by a previously
                 * allocated crtc, we create a new crtc for it
                 */
                if (!channel_used(dev, channel)) {
                        ret = omap_modeset_create_crtc(dev, id, channel);
                        if (ret < 0) {
                                dev_err(dev->dev,
                                        "could not create CRTC (channel %u)\n",
                                        channel);
                                return ret;
                        }

                        id++;
                }
        }

        /*
         * we have allocated crtcs according to the need of the panels/encoders,
         * adding more crtcs here if needed
         */
        for (; id < num_crtcs; id++) {

                /* find a free manager for this crtc */
                for (i = 0; i < num_mgrs; i++) {
                        if (!channel_used(dev, i))
                                break;
                }

                if (i == num_mgrs) {
                        /* this shouldn't really happen */
                        dev_err(dev->dev, "no managers left for crtc\n");
                        return -ENOMEM;
                }

                ret = omap_modeset_create_crtc(dev, id, i);
                if (ret < 0) {
                        dev_err(dev->dev,
                                "could not create CRTC (channel %u)\n", i);
                        return ret;
                }
        }

        /*
         * Create normal planes for the remaining overlays:
         */
        for (; id < num_ovls; id++) {
                struct drm_plane *plane;

                plane = omap_plane_init(dev, id, DRM_PLANE_TYPE_OVERLAY);
                if (IS_ERR(plane))
                        return PTR_ERR(plane);

                BUG_ON(priv->num_planes >= ARRAY_SIZE(priv->planes));
                priv->planes[priv->num_planes++] = plane;
        }

        for (i = 0; i < priv->num_encoders; i++) {
                struct drm_encoder *encoder = priv->encoders[i];
                struct omap_dss_device *dssdev =
                                        omap_encoder_get_dssdev(encoder);
                struct omap_dss_device *output;

                output = omapdss_find_output_from_display(dssdev);

                /* figure out which crtc's we can connect the encoder to: */
                encoder->possible_crtcs = 0;
                for (id = 0; id < priv->num_crtcs; id++) {
                        struct drm_crtc *crtc = priv->crtcs[id];
                        enum omap_channel crtc_channel;

                        crtc_channel = omap_crtc_channel(crtc);

                        if (output->dispc_channel == crtc_channel) {
                                encoder->possible_crtcs |= (1 << id);
                                break;
                        }
                }

                omap_dss_put_device(output);
        }

        DBG("registered %d planes, %d crtcs, %d encoders and %d connectors\n",
                priv->num_planes, priv->num_crtcs, priv->num_encoders,
                priv->num_connectors);

        dev->mode_config.min_width = 32;
        dev->mode_config.min_height = 32;

        /* note: eventually will need some cpu_is_omapXYZ() type stuff here
         * to fill in these limits properly on different OMAP generations..
         */
        dev->mode_config.max_width = 2048;
        dev->mode_config.max_height = 2048;

        dev->mode_config.funcs = &omap_mode_config_funcs;

        return 0;
}

static void omap_modeset_free(struct drm_device *dev)
{
        drm_mode_config_cleanup(dev);
}

/*
 * drm ioctl funcs
 */


static int ioctl_get_param(struct drm_device *dev, void *data,
                struct drm_file *file_priv)
{
        struct omap_drm_private *priv = dev->dev_private;
        struct drm_omap_param *args = data;

        DBG("%p: param=%llu", dev, args->param);

        switch (args->param) {
        case OMAP_PARAM_CHIPSET_ID:
                args->value = priv->omaprev;
                break;
        default:
                DBG("unknown parameter %lld", args->param);
                return -EINVAL;
        }

        return 0;
}

static int ioctl_set_param(struct drm_device *dev, void *data,
                struct drm_file *file_priv)
{
        struct drm_omap_param *args = data;

        switch (args->param) {
        default:
                DBG("unknown parameter %lld", args->param);
                return -EINVAL;
        }

        return 0;
}

static int ioctl_gem_new(struct drm_device *dev, void *data,
                struct drm_file *file_priv)
{
        struct drm_omap_gem_new *args = data;
        VERB("%p:%p: size=0x%08x, flags=%08x", dev, file_priv,
                        args->size.bytes, args->flags);
        return omap_gem_new_handle(dev, file_priv, args->size,
                        args->flags, &args->handle);
}

static int ioctl_gem_cpu_prep(struct drm_device *dev, void *data,
                struct drm_file *file_priv)
{
        struct drm_omap_gem_cpu_prep *args = data;
        struct drm_gem_object *obj;
        int ret;

        VERB("%p:%p: handle=%d, op=%x", dev, file_priv, args->handle, args->op);

        obj = drm_gem_object_lookup(dev, file_priv, args->handle);
        if (!obj)
                return -ENOENT;

        ret = omap_gem_op_sync(obj, args->op);

        if (!ret)
                ret = omap_gem_op_start(obj, args->op);

        drm_gem_object_unreference_unlocked(obj);

        return ret;
}

static int ioctl_gem_cpu_fini(struct drm_device *dev, void *data,
                struct drm_file *file_priv)
{
        struct drm_omap_gem_cpu_fini *args = data;
        struct drm_gem_object *obj;
        int ret;

        VERB("%p:%p: handle=%d", dev, file_priv, args->handle);

        obj = drm_gem_object_lookup(dev, file_priv, args->handle);
        if (!obj)
                return -ENOENT;

        /* XXX flushy, flushy */
        ret = 0;

        if (!ret)
                ret = omap_gem_op_finish(obj, args->op);

        drm_gem_object_unreference_unlocked(obj);

        return ret;
}

static int ioctl_gem_info(struct drm_device *dev, void *data,
                struct drm_file *file_priv)
{
        struct drm_omap_gem_info *args = data;
        struct drm_gem_object *obj;
        int ret = 0;

        VERB("%p:%p: handle=%d", dev, file_priv, args->handle);

        obj = drm_gem_object_lookup(dev, file_priv, args->handle);
        if (!obj)
                return -ENOENT;

        args->size = omap_gem_mmap_size(obj);
        args->offset = omap_gem_mmap_offset(obj);

        drm_gem_object_unreference_unlocked(obj);

        return ret;
}

static const struct drm_ioctl_desc ioctls[DRM_COMMAND_END - DRM_COMMAND_BASE] = {
        DRM_IOCTL_DEF_DRV(OMAP_GET_PARAM, ioctl_get_param, DRM_UNLOCKED|DRM_AUTH),
        DRM_IOCTL_DEF_DRV(OMAP_SET_PARAM, ioctl_set_param, DRM_UNLOCKED|DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
        DRM_IOCTL_DEF_DRV(OMAP_GEM_NEW, ioctl_gem_new, DRM_UNLOCKED|DRM_AUTH),
        DRM_IOCTL_DEF_DRV(OMAP_GEM_CPU_PREP, ioctl_gem_cpu_prep, DRM_UNLOCKED|DRM_AUTH),
        DRM_IOCTL_DEF_DRV(OMAP_GEM_CPU_FINI, ioctl_gem_cpu_fini, DRM_UNLOCKED|DRM_AUTH),
        DRM_IOCTL_DEF_DRV(OMAP_GEM_INFO, ioctl_gem_info, DRM_UNLOCKED|DRM_AUTH),
};

/*
 * drm driver funcs
 */

/**
 * load - setup chip and create an initial config
 * @dev: DRM device
 * @flags: startup flags
 *
 * The driver load routine has to do several things:
 *   - initialize the memory manager
 *   - allocate initial config memory
 *   - setup the DRM framebuffer with the allocated memory
 */
static int dev_load(struct drm_device *dev, unsigned long flags)
{
        struct omap_drm_platform_data *pdata = dev->dev->platform_data;
        struct omap_drm_private *priv;
        int ret;

        DBG("load: dev=%p", dev);

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

        priv->omaprev = pdata->omaprev;

        dev->dev_private = priv;

        priv->wq = alloc_ordered_workqueue("omapdrm", 0);

        spin_lock_init(&priv->list_lock);
        INIT_LIST_HEAD(&priv->obj_list);

        omap_gem_init(dev);

        ret = omap_modeset_init(dev);
        if (ret) {
                dev_err(dev->dev, "omap_modeset_init failed: ret=%d\n", ret);
                dev->dev_private = NULL;
                kfree(priv);
                return ret;
        }

        ret = drm_vblank_init(dev, priv->num_crtcs);
        if (ret)
                dev_warn(dev->dev, "could not init vblank\n");

        priv->fbdev = omap_fbdev_init(dev);
        if (!priv->fbdev) {
                dev_warn(dev->dev, "omap_fbdev_init failed\n");
                /* well, limp along without an fbdev.. maybe X11 will work? */
        }

        /* store off drm_device for use in pm ops */
        dev_set_drvdata(dev->dev, dev);

        drm_kms_helper_poll_init(dev);

        return 0;
}

static int dev_unload(struct drm_device *dev)
{
        struct omap_drm_private *priv = dev->dev_private;
        int i;

        DBG("unload: dev=%p", dev);

        drm_kms_helper_poll_fini(dev);

        if (priv->fbdev)
                omap_fbdev_free(dev);

        /* flush crtcs so the fbs get released */
        for (i = 0; i < priv->num_crtcs; i++)
                omap_crtc_flush(priv->crtcs[i]);

        omap_modeset_free(dev);
        omap_gem_deinit(dev);

        destroy_workqueue(priv->wq);

        drm_vblank_cleanup(dev);
        omap_drm_irq_uninstall(dev);

        kfree(dev->dev_private);
        dev->dev_private = NULL;

        dev_set_drvdata(dev->dev, NULL);

        return 0;
}

static int dev_open(struct drm_device *dev, struct drm_file *file)
{
        file->driver_priv = NULL;

        DBG("open: dev=%p, file=%p", dev, file);

        return 0;
}

/**
 * lastclose - clean up after all DRM clients have exited
 * @dev: DRM device
 *
 * Take care of cleaning up after all DRM clients have exited.  In the
 * mode setting case, we want to restore the kernel's initial mode (just
 * in case the last client left us in a bad state).
 */
static void dev_lastclose(struct drm_device *dev)
{
        int i;

        /* we don't support vga-switcheroo.. so just make sure the fbdev
         * mode is active
         */
        struct omap_drm_private *priv = dev->dev_private;
        int ret;

        DBG("lastclose: dev=%p", dev);

        if (priv->rotation_prop) {
                /* need to restore default rotation state.. not sure
                 * if there is a cleaner way to restore properties to
                 * default state?  Maybe a flag that properties should
                 * automatically be restored to default state on
                 * lastclose?
                 */
                for (i = 0; i < priv->num_crtcs; i++) {
                        drm_object_property_set_value(&priv->crtcs[i]->base,
                                        priv->rotation_prop, 0);
                }

                for (i = 0; i < priv->num_planes; i++) {
                        drm_object_property_set_value(&priv->planes[i]->base,
                                        priv->rotation_prop, 0);
                }
        }

        if (priv->fbdev) {
                ret = drm_fb_helper_restore_fbdev_mode_unlocked(priv->fbdev);
                if (ret)
                        DBG("failed to restore crtc mode");
        }
}

static void dev_preclose(struct drm_device *dev, struct drm_file *file)
{
        DBG("preclose: dev=%p", dev);
}

static void dev_postclose(struct drm_device *dev, struct drm_file *file)
{
        DBG("postclose: dev=%p, file=%p", dev, file);
}

static const struct vm_operations_struct omap_gem_vm_ops = {
        .fault = omap_gem_fault,
        .open = drm_gem_vm_open,
        .close = drm_gem_vm_close,
};

static const struct file_operations omapdriver_fops = {
        .owner = THIS_MODULE,
        .open = drm_open,
        .unlocked_ioctl = drm_ioctl,
        .release = drm_release,
        .mmap = omap_gem_mmap,
        .poll = drm_poll,
        .read = drm_read,
        .llseek = noop_llseek,
};

static struct drm_driver omap_drm_driver = {
        .driver_features = DRIVER_HAVE_IRQ | DRIVER_MODESET | DRIVER_GEM
                         | DRIVER_PRIME,
        .load = dev_load,
        .unload = dev_unload,
        .open = dev_open,
        .lastclose = dev_lastclose,
        .preclose = dev_preclose,
        .postclose = dev_postclose,
        .set_busid = drm_platform_set_busid,
        .get_vblank_counter = drm_vblank_count,
        .enable_vblank = omap_irq_enable_vblank,
        .disable_vblank = omap_irq_disable_vblank,
        .irq_preinstall = omap_irq_preinstall,
        .irq_postinstall = omap_irq_postinstall,
        .irq_uninstall = omap_irq_uninstall,
        .irq_handler = omap_irq_handler,
#ifdef CONFIG_DEBUG_FS
        .debugfs_init = omap_debugfs_init,
        .debugfs_cleanup = omap_debugfs_cleanup,
#endif
        .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
        .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
        .gem_prime_export = omap_gem_prime_export,
        .gem_prime_import = omap_gem_prime_import,
        .gem_free_object = omap_gem_free_object,
        .gem_vm_ops = &omap_gem_vm_ops,
        .dumb_create = omap_gem_dumb_create,
        .dumb_map_offset = omap_gem_dumb_map_offset,
        .dumb_destroy = drm_gem_dumb_destroy,
        .ioctls = ioctls,
        .num_ioctls = DRM_OMAP_NUM_IOCTLS,
        .fops = &omapdriver_fops,
        .name = DRIVER_NAME,
        .desc = DRIVER_DESC,
        .date = DRIVER_DATE,
        .major = DRIVER_MAJOR,
        .minor = DRIVER_MINOR,
        .patchlevel = DRIVER_PATCHLEVEL,
};

static int pdev_probe(struct platform_device *device)
{
        int r;

        if (omapdss_is_initialized() == false)
                return -EPROBE_DEFER;

        omap_crtc_pre_init();

        r = omap_connect_dssdevs();
        if (r) {
                omap_crtc_pre_uninit();
                return r;
        }

        DBG("%s", device->name);
        return drm_platform_init(&omap_drm_driver, device);
}

static int pdev_remove(struct platform_device *device)
{
        DBG("");

        drm_put_dev(platform_get_drvdata(device));

        omap_disconnect_dssdevs();
        omap_crtc_pre_uninit();

        return 0;
}

#ifdef CONFIG_PM_SLEEP
static int omap_drm_suspend(struct device *dev)
{
        struct drm_device *drm_dev = dev_get_drvdata(dev);

        drm_kms_helper_poll_disable(drm_dev);

        return 0;
}

static int omap_drm_resume(struct device *dev)
{
        struct drm_device *drm_dev = dev_get_drvdata(dev);

        drm_kms_helper_poll_enable(drm_dev);

        return omap_gem_resume(dev);
}
#endif

static SIMPLE_DEV_PM_OPS(omapdrm_pm_ops, omap_drm_suspend, omap_drm_resume);

static struct platform_driver pdev = {
        .driver = {
                .name = DRIVER_NAME,
                .pm = &omapdrm_pm_ops,
        },
        .probe = pdev_probe,
        .remove = pdev_remove,
};

static int __init omap_drm_init(void)
{
        int r;

        DBG("init");

        r = platform_driver_register(&omap_dmm_driver);
        if (r) {
                pr_err("DMM driver registration failed\n");
                return r;
        }

        r = platform_driver_register(&pdev);
        if (r) {
                pr_err("omapdrm driver registration failed\n");
                platform_driver_unregister(&omap_dmm_driver);
                return r;
        }

        return 0;
}

static void __exit omap_drm_fini(void)
{
        DBG("fini");

        platform_driver_unregister(&pdev);

        platform_driver_unregister(&omap_dmm_driver);
}

/* need late_initcall() so we load after dss_driver's are loaded */
late_initcall(omap_drm_init);
module_exit(omap_drm_fini);

MODULE_AUTHOR("Rob Clark <rob@ti.com>");
MODULE_DESCRIPTION("OMAP DRM Display Driver");
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_LICENSE("GPL v2");