/**
 * \file drm_debugfs.c
 * debugfs support for DRM
 *
 * \author Ben Gamari <bgamari@gmail.com>
 */

/*
 * Created: Sun Dec 21 13:08:50 2008 by bgamari@gmail.com
 *
 * Copyright 2008 Ben Gamari <bgamari@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_edid.h>
#include "drm_internal.h"

#if defined(CONFIG_DEBUG_FS)

/***************************************************
 * Initialization, etc.
 **************************************************/

static const struct drm_info_list drm_debugfs_list[] = {
        {"name", drm_name_info, 0},
        {"clients", drm_clients_info, 0},
        {"gem_names", drm_gem_name_info, DRIVER_GEM},
};
#define DRM_DEBUGFS_ENTRIES ARRAY_SIZE(drm_debugfs_list)


static int drm_debugfs_open(struct inode *inode, struct file *file)
{
        struct drm_info_node *node = inode->i_private;

        return single_open(file, node->info_ent->show, node);
}


static const struct file_operations drm_debugfs_fops = {
        .owner = THIS_MODULE,
        .open = drm_debugfs_open,
        .read = seq_read,
        .llseek = seq_lseek,
        .release = single_release,
};


/**
 * Initialize a given set of debugfs files for a device
 *
 * \param files The array of files to create
 * \param count The number of files given
 * \param root DRI debugfs dir entry.
 * \param minor device minor number
 * \return Zero on success, non-zero on failure
 *
 * Create a given set of debugfs files represented by an array of
 * gdm_debugfs_lists in the given root directory.
 */
int drm_debugfs_create_files(const struct drm_info_list *files, int count,
                             struct dentry *root, struct drm_minor *minor)
{
        struct drm_device *dev = minor->dev;
        struct dentry *ent;
        struct drm_info_node *tmp;
        int i, ret;

        for (i = 0; i < count; i++) {
                u32 features = files[i].driver_features;

                if (features != 0 &&
                    (dev->driver->driver_features & features) != features)
                        continue;

                tmp = kmalloc(sizeof(struct drm_info_node), GFP_KERNEL);
                if (tmp == NULL) {
                        ret = -1;
                        goto fail;
                }
                ent = debugfs_create_file(files[i].name, S_IFREG | S_IRUGO,
                                          root, tmp, &drm_debugfs_fops);
                if (!ent) {
                        DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s/%s\n",
                                  root->d_name.name, files[i].name);
                        kfree(tmp);
                        ret = -1;
                        goto fail;
                }

                tmp->minor = minor;
                tmp->dent = ent;
                tmp->info_ent = &files[i];

                mutex_lock(&minor->debugfs_lock);
                list_add(&tmp->list, &minor->debugfs_list);
                mutex_unlock(&minor->debugfs_lock);
        }
        return 0;

fail:
        drm_debugfs_remove_files(files, count, minor);
        return ret;
}
EXPORT_SYMBOL(drm_debugfs_create_files);

/**
 * Initialize the DRI debugfs filesystem for a device
 *
 * \param dev DRM device
 * \param minor device minor number
 * \param root DRI debugfs dir entry.
 *
 * Create the DRI debugfs root entry "/sys/kernel/debug/dri", the device debugfs root entry
 * "/sys/kernel/debug/dri/%minor%/", and each entry in debugfs_list as
 * "/sys/kernel/debug/dri/%minor%/%name%".
 */
int drm_debugfs_init(struct drm_minor *minor, int minor_id,
                     struct dentry *root)
{
        struct drm_device *dev = minor->dev;
        char name[64];
        int ret;

        INIT_LIST_HEAD(&minor->debugfs_list);
        mutex_init(&minor->debugfs_lock);
        sprintf(name, "%d", minor_id);
        minor->debugfs_root = debugfs_create_dir(name, root);
        if (!minor->debugfs_root) {
                DRM_ERROR("Cannot create /sys/kernel/debug/dri/%s\n", name);
                return -1;
        }

        ret = drm_debugfs_create_files(drm_debugfs_list, DRM_DEBUGFS_ENTRIES,
                                       minor->debugfs_root, minor);
        if (ret) {
                debugfs_remove(minor->debugfs_root);
                minor->debugfs_root = NULL;
                DRM_ERROR("Failed to create core drm debugfs files\n");
                return ret;
        }

        if (dev->driver->debugfs_init) {
                ret = dev->driver->debugfs_init(minor);
                if (ret) {
                        DRM_ERROR("DRM: Driver failed to initialize "
                                  "/sys/kernel/debug/dri.\n");
                        return ret;
                }
        }
        return 0;
}


/**
 * Remove a list of debugfs files
 *
 * \param files The list of files
 * \param count The number of files
 * \param minor The minor of which we should remove the files
 * \return always zero.
 *
 * Remove all debugfs entries created by debugfs_init().
 */
int drm_debugfs_remove_files(const struct drm_info_list *files, int count,
                             struct drm_minor *minor)
{
        struct list_head *pos, *q;
        struct drm_info_node *tmp;
        int i;

        mutex_lock(&minor->debugfs_lock);
        for (i = 0; i < count; i++) {
                list_for_each_safe(pos, q, &minor->debugfs_list) {
                        tmp = list_entry(pos, struct drm_info_node, list);
                        if (tmp->info_ent == &files[i]) {
                                debugfs_remove(tmp->dent);
                                list_del(pos);
                                kfree(tmp);
                        }
                }
        }
        mutex_unlock(&minor->debugfs_lock);
        return 0;
}
EXPORT_SYMBOL(drm_debugfs_remove_files);

/**
 * Cleanup the debugfs filesystem resources.
 *
 * \param minor device minor number.
 * \return always zero.
 *
 * Remove all debugfs entries created by debugfs_init().
 */
int drm_debugfs_cleanup(struct drm_minor *minor)
{
        struct drm_device *dev = minor->dev;

        if (!minor->debugfs_root)
                return 0;

        if (dev->driver->debugfs_cleanup)
                dev->driver->debugfs_cleanup(minor);

        drm_debugfs_remove_files(drm_debugfs_list, DRM_DEBUGFS_ENTRIES, minor);

        debugfs_remove(minor->debugfs_root);
        minor->debugfs_root = NULL;

        return 0;
}

static int connector_show(struct seq_file *m, void *data)
{
        struct drm_connector *connector = m->private;
        const char *status;

        switch (connector->force) {
        case DRM_FORCE_ON:
                status = "on\n";
                break;

        case DRM_FORCE_ON_DIGITAL:
                status = "digital\n";
                break;

        case DRM_FORCE_OFF:
                status = "off\n";
                break;

        case DRM_FORCE_UNSPECIFIED:
                status = "unspecified\n";
                break;

        default:
                return 0;
        }

        seq_puts(m, status);

        return 0;
}

static int connector_open(struct inode *inode, struct file *file)
{
        struct drm_connector *dev = inode->i_private;

        return single_open(file, connector_show, dev);
}

static ssize_t connector_write(struct file *file, const char __user *ubuf,
                               size_t len, loff_t *offp)
{
        struct seq_file *m = file->private_data;
        struct drm_connector *connector = m->private;
        char buf[12];

        if (len > sizeof(buf) - 1)
                return -EINVAL;

        if (copy_from_user(buf, ubuf, len))
                return -EFAULT;

        buf[len] = '\0';

        if (!strcmp(buf, "on"))
                connector->force = DRM_FORCE_ON;
        else if (!strcmp(buf, "digital"))
                connector->force = DRM_FORCE_ON_DIGITAL;
        else if (!strcmp(buf, "off"))
                connector->force = DRM_FORCE_OFF;
        else if (!strcmp(buf, "unspecified"))
                connector->force = DRM_FORCE_UNSPECIFIED;
        else
                return -EINVAL;

        return len;
}

static int edid_show(struct seq_file *m, void *data)
{
        struct drm_connector *connector = m->private;
        struct drm_property_blob *edid = connector->edid_blob_ptr;

        if (connector->override_edid && edid)
                seq_write(m, edid->data, edid->length);

        return 0;
}

static int edid_open(struct inode *inode, struct file *file)
{
        struct drm_connector *dev = inode->i_private;

        return single_open(file, edid_show, dev);
}

static ssize_t edid_write(struct file *file, const char __user *ubuf,
                          size_t len, loff_t *offp)
{
        struct seq_file *m = file->private_data;
        struct drm_connector *connector = m->private;
        char *buf;
        struct edid *edid;
        int ret;

        buf = memdup_user(ubuf, len);
        if (IS_ERR(buf))
                return PTR_ERR(buf);

        edid = (struct edid *) buf;

        if (len == 5 && !strncmp(buf, "reset", 5)) {
                connector->override_edid = false;
                ret = drm_mode_connector_update_edid_property(connector, NULL);
        } else if (len < EDID_LENGTH ||
                   EDID_LENGTH * (1 + edid->extensions) > len)
                ret = -EINVAL;
        else {
                connector->override_edid = false;
                ret = drm_mode_connector_update_edid_property(connector, edid);
                if (!ret)
                        connector->override_edid = true;
        }

        kfree(buf);

        return (ret) ? ret : len;
}

static const struct file_operations drm_edid_fops = {
        .owner = THIS_MODULE,
        .open = edid_open,
        .read = seq_read,
        .llseek = seq_lseek,
        .release = single_release,
        .write = edid_write
};


static const struct file_operations drm_connector_fops = {
        .owner = THIS_MODULE,
        .open = connector_open,
        .read = seq_read,
        .llseek = seq_lseek,
        .release = single_release,
        .write = connector_write
};

int drm_debugfs_connector_add(struct drm_connector *connector)
{
        struct drm_minor *minor = connector->dev->primary;
        struct dentry *root, *ent;

        if (!minor->debugfs_root)
                return -1;

        root = debugfs_create_dir(connector->name, minor->debugfs_root);
        if (!root)
                return -ENOMEM;

        connector->debugfs_entry = root;

        /* force */
        ent = debugfs_create_file("force", S_IRUGO | S_IWUSR, root, connector,
                                  &drm_connector_fops);
        if (!ent)
                goto error;

        /* edid */
        ent = debugfs_create_file("edid_override", S_IRUGO | S_IWUSR, root,
                                  connector, &drm_edid_fops);
        if (!ent)
                goto error;

        return 0;

error:
        debugfs_remove_recursive(connector->debugfs_entry);
        connector->debugfs_entry = NULL;
        return -ENOMEM;
}

void drm_debugfs_connector_remove(struct drm_connector *connector)
{
        if (!connector->debugfs_entry)
                return;

        debugfs_remove_recursive(connector->debugfs_entry);

        connector->debugfs_entry = NULL;
}

#endif /* CONFIG_DEBUG_FS */