/*
   * Ultra Wide Band
   * Debug support
   *
   * Copyright (C) 2005-2006 Intel Corporation
   * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   * Copyright (C) 2008 Cambridge Silicon Radio Ltd.
   *
   * 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, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   * 02110-1301, USA.
   *
   *
   * FIXME: doc
   */
  
  #include <linux/spinlock.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/notifier.h>
  #include <linux/device.h>
  #include <linux/debugfs.h>
  #include <linux/uaccess.h>
  #include <linux/seq_file.h>
  
  #include <linux/uwb/debug-cmd.h>
  
  #include "uwb-internal.h"
  
  /*
   * Debug interface
   *
   * Per radio controller debugfs files (in uwb/uwbN/):
   *
   * command: Flexible command interface (see <linux/uwb/debug-cmd.h>).
   *
   * reservations: information on reservations.
   *
   * accept: Set to true (Y or 1) to accept reservation requests from
   * peers.
   *
   * drp_avail: DRP availability information.
   */
  
  struct uwb_dbg {
  	struct uwb_pal pal;
  
  	u32 accept;
  	struct list_head rsvs;
  
  	struct dentry *root_d;
  	struct dentry *command_f;
  	struct dentry *reservations_f;
  	struct dentry *accept_f;
  	struct dentry *drp_avail_f;
  	spinlock_t list_lock;
  };
  
  static struct dentry *root_dir;
  
  static void uwb_dbg_rsv_cb(struct uwb_rsv *rsv)
  {
  	struct uwb_dbg *dbg = rsv->pal_priv;
  
  	uwb_rsv_dump("debug", rsv);
  
  	if (rsv->state == UWB_RSV_STATE_NONE) {
  		spin_lock(&dbg->list_lock);
  		list_del(&rsv->pal_node);
  		spin_unlock(&dbg->list_lock);
  		uwb_rsv_destroy(rsv);
  	}
  }
  
  static int cmd_rsv_establish(struct uwb_rc *rc,
  			     struct uwb_dbg_cmd_rsv_establish *cmd)
  {
  	struct uwb_mac_addr macaddr;
  	struct uwb_rsv *rsv;
  	struct uwb_dev *target;
  	int ret;
  
  	memcpy(&macaddr, cmd->target, sizeof(macaddr));
  	target = uwb_dev_get_by_macaddr(rc, &macaddr);
  	if (target == NULL)
  		return -ENODEV;
  
  	rsv = uwb_rsv_create(rc, uwb_dbg_rsv_cb, rc->dbg);
  	if (rsv == NULL) {
  		uwb_dev_put(target);
  		return -ENOMEM;
  	}
  
  	rsv->target.type  = UWB_RSV_TARGET_DEV;
  	rsv->target.dev   = target;
  	rsv->type         = cmd->type;
  	rsv->max_mas      = cmd->max_mas;
  	rsv->min_mas      = cmd->min_mas;
  	rsv->max_interval = cmd->max_interval;
  
  	ret = uwb_rsv_establish(rsv);
  	if (ret)
  		uwb_rsv_destroy(rsv);
  	else {
  		spin_lock(&(rc->dbg)->list_lock);
  		list_add_tail(&rsv->pal_node, &rc->dbg->rsvs);
  		spin_unlock(&(rc->dbg)->list_lock);
  	}
  	return ret;
  }
  
  static int cmd_rsv_terminate(struct uwb_rc *rc,
  			     struct uwb_dbg_cmd_rsv_terminate *cmd)
  {
  	struct uwb_rsv *rsv, *found = NULL;
  	int i = 0;
  
  	spin_lock(&(rc->dbg)->list_lock);
  
  	list_for_each_entry(rsv, &rc->dbg->rsvs, pal_node) {
  		if (i == cmd->index) {
  			found = rsv;
  			uwb_rsv_get(found);
  			break;
  		}
  		i++;
  	}
  
  	spin_unlock(&(rc->dbg)->list_lock);
  
  	if (!found)
  		return -EINVAL;
  
  	uwb_rsv_terminate(found);
  	uwb_rsv_put(found);
  
  	return 0;
  }
  
  static int cmd_ie_add(struct uwb_rc *rc, struct uwb_dbg_cmd_ie *ie_to_add)
  {
  	return uwb_rc_ie_add(rc,
  			     (const struct uwb_ie_hdr *) ie_to_add->data,
  			     ie_to_add->len);
  }
  
  static int cmd_ie_rm(struct uwb_rc *rc, struct uwb_dbg_cmd_ie *ie_to_rm)
  {
  	return uwb_rc_ie_rm(rc, ie_to_rm->data[0]);
  }
  
  static ssize_t command_write(struct file *file, const char __user *buf,
  			 size_t len, loff_t *off)
  {
  	struct uwb_rc *rc = file->private_data;
  	struct uwb_dbg_cmd cmd;
  	int ret = 0;
  	
  	if (len != sizeof(struct uwb_dbg_cmd))
  		return -EINVAL;
  
  	if (copy_from_user(&cmd, buf, len) != 0)
  		return -EFAULT;
  
  	switch (cmd.type) {
  	case UWB_DBG_CMD_RSV_ESTABLISH:
  		ret = cmd_rsv_establish(rc, &cmd.rsv_establish);
  		break;
  	case UWB_DBG_CMD_RSV_TERMINATE:
  		ret = cmd_rsv_terminate(rc, &cmd.rsv_terminate);
  		break;
  	case UWB_DBG_CMD_IE_ADD:
  		ret = cmd_ie_add(rc, &cmd.ie_add);
  		break;
  	case UWB_DBG_CMD_IE_RM:
  		ret = cmd_ie_rm(rc, &cmd.ie_rm);
  		break;
  	case UWB_DBG_CMD_RADIO_START:
  		ret = uwb_radio_start(&rc->dbg->pal);
  		break;
  	case UWB_DBG_CMD_RADIO_STOP:
  		uwb_radio_stop(&rc->dbg->pal);
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	return ret < 0 ? ret : len;
  }
  
  static const struct file_operations command_fops = {
  	.open	= simple_open,
  	.write  = command_write,
  	.read   = NULL,
  	.llseek = no_llseek,
  	.owner  = THIS_MODULE,
  };
  
  static int reservations_print(struct seq_file *s, void *p)
  {
  	struct uwb_rc *rc = s->private;
  	struct uwb_rsv *rsv;
  
  	mutex_lock(&rc->rsvs_mutex);
  
  	list_for_each_entry(rsv, &rc->reservations, rc_node) {
  		struct uwb_dev_addr devaddr;
  		char owner[UWB_ADDR_STRSIZE], target[UWB_ADDR_STRSIZE];
  		bool is_owner;
  		char buf[72];
  
  		uwb_dev_addr_print(owner, sizeof(owner), &rsv->owner->dev_addr);
  		if (rsv->target.type == UWB_RSV_TARGET_DEV) {
  			devaddr = rsv->target.dev->dev_addr;
  			is_owner = &rc->uwb_dev == rsv->owner;
  		} else {
  			devaddr = rsv->target.devaddr;
  			is_owner = true;
  		}
  		uwb_dev_addr_print(target, sizeof(target), &devaddr);
  
  		seq_printf(s, "%c %s -> %s: %s
  ",
  			   is_owner ? 'O' : 'T',
  			   owner, target, uwb_rsv_state_str(rsv->state));
  		seq_printf(s, "  stream: %d  type: %s
  ",
  			   rsv->stream, uwb_rsv_type_str(rsv->type));
  		bitmap_scnprintf(buf, sizeof(buf), rsv->mas.bm, UWB_NUM_MAS);
  		seq_printf(s, "  %s
  ", buf);
  	}
  
  	mutex_unlock(&rc->rsvs_mutex);
  
  	return 0;
  }
  
  static int reservations_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, reservations_print, inode->i_private);
  }
  
  static const struct file_operations reservations_fops = {
  	.open    = reservations_open,
  	.read    = seq_read,
  	.llseek  = seq_lseek,
  	.release = single_release,
  	.owner   = THIS_MODULE,
  };
  
  static int drp_avail_print(struct seq_file *s, void *p)
  {
  	struct uwb_rc *rc = s->private;
  	char buf[72];
  
  	bitmap_scnprintf(buf, sizeof(buf), rc->drp_avail.global, UWB_NUM_MAS);
  	seq_printf(s, "global:  %s
  ", buf);
  	bitmap_scnprintf(buf, sizeof(buf), rc->drp_avail.local, UWB_NUM_MAS);
  	seq_printf(s, "local:   %s
  ", buf);
  	bitmap_scnprintf(buf, sizeof(buf), rc->drp_avail.pending, UWB_NUM_MAS);
  	seq_printf(s, "pending: %s
  ", buf);
  
  	return 0;
  }
  
  static int drp_avail_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, drp_avail_print, inode->i_private);
  }
  
  static const struct file_operations drp_avail_fops = {
  	.open    = drp_avail_open,
  	.read    = seq_read,
  	.llseek  = seq_lseek,
  	.release = single_release,
  	.owner   = THIS_MODULE,
  };
  
  static void uwb_dbg_channel_changed(struct uwb_pal *pal, int channel)
  {
  	struct device *dev = &pal->rc->uwb_dev.dev;
  
  	if (channel > 0)
  		dev_info(dev, "debug: channel %d started
  ", channel);
  	else
  		dev_info(dev, "debug: channel stopped
  ");
  }
  
  static void uwb_dbg_new_rsv(struct uwb_pal *pal, struct uwb_rsv *rsv)
  {
  	struct uwb_dbg *dbg = container_of(pal, struct uwb_dbg, pal);
  
  	if (dbg->accept) {
  		spin_lock(&dbg->list_lock);
  		list_add_tail(&rsv->pal_node, &dbg->rsvs);
  		spin_unlock(&dbg->list_lock);
  		uwb_rsv_accept(rsv, uwb_dbg_rsv_cb, dbg);
  	}
  }
  
  /**
   * uwb_dbg_add_rc - add a debug interface for a radio controller
   * @rc: the radio controller
   */
  void uwb_dbg_add_rc(struct uwb_rc *rc)
  {
  	rc->dbg = kzalloc(sizeof(struct uwb_dbg), GFP_KERNEL);
  	if (rc->dbg == NULL)
  		return;
  
  	INIT_LIST_HEAD(&rc->dbg->rsvs);
  	spin_lock_init(&(rc->dbg)->list_lock);
  
  	uwb_pal_init(&rc->dbg->pal);
  	rc->dbg->pal.rc = rc;
  	rc->dbg->pal.channel_changed = uwb_dbg_channel_changed;
  	rc->dbg->pal.new_rsv = uwb_dbg_new_rsv;
  	uwb_pal_register(&rc->dbg->pal);
  
  	if (root_dir) {
  		rc->dbg->root_d = debugfs_create_dir(dev_name(&rc->uwb_dev.dev),
  						     root_dir);
  		rc->dbg->command_f = debugfs_create_file("command", 0200,
  							 rc->dbg->root_d, rc,
  							 &command_fops);
  		rc->dbg->reservations_f = debugfs_create_file("reservations", 0444,
  							      rc->dbg->root_d, rc,
  							      &reservations_fops);
  		rc->dbg->accept_f = debugfs_create_bool("accept", 0644,
  							rc->dbg->root_d,
  							&rc->dbg->accept);
  		rc->dbg->drp_avail_f = debugfs_create_file("drp_avail", 0444,
  							   rc->dbg->root_d, rc,
  							   &drp_avail_fops);
  	}
  }
  
  /**
   * uwb_dbg_del_rc - remove a radio controller's debug interface
   * @rc: the radio controller
   */
  void uwb_dbg_del_rc(struct uwb_rc *rc)
  {
  	struct uwb_rsv *rsv, *t;
  
  	if (rc->dbg == NULL)
  		return;
  
  	list_for_each_entry_safe(rsv, t, &rc->dbg->rsvs, pal_node) {
  		uwb_rsv_terminate(rsv);
  	}
  
  	uwb_pal_unregister(&rc->dbg->pal);
  
  	if (root_dir) {
  		debugfs_remove(rc->dbg->drp_avail_f);
  		debugfs_remove(rc->dbg->accept_f);
  		debugfs_remove(rc->dbg->reservations_f);
  		debugfs_remove(rc->dbg->command_f);
  		debugfs_remove(rc->dbg->root_d);
  	}
  }
  
  /**
   * uwb_dbg_exit - initialize the debug interface sub-module
   */
  void uwb_dbg_init(void)
  {
  	root_dir = debugfs_create_dir("uwb", NULL);
  }
  
  /**
   * uwb_dbg_exit - clean-up the debug interface sub-module
   */
  void uwb_dbg_exit(void)
  {
  	debugfs_remove(root_dir);
  }
  
  /**
   * uwb_dbg_create_pal_dir - create a debugfs directory for a PAL
   * @pal: The PAL.
   */
  struct dentry *uwb_dbg_create_pal_dir(struct uwb_pal *pal)
  {
  	struct uwb_rc *rc = pal->rc;
  
  	if (root_dir && rc->dbg && rc->dbg->root_d && pal->name)
  		return debugfs_create_dir(pal->name, rc->dbg->root_d);
  	return NULL;
  }