/*

   *  Force feedback support for PantherLord/GreenAsia based devices
   *
   *  The devices are distributed under various names and the same USB device ID
   *  can be used in both adapters and actual game controllers.
   *
   *  0810:0001 "Twin USB Joystick"
   *   - tested with PantherLord USB/PS2 2in1 Adapter
   *   - contains two reports, one for each port (HID_QUIRK_MULTI_INPUT)
   *
   *  0e8f:0003 "GreenAsia Inc.    USB Joystick     "

   *   - tested with König Gaming gamepad

   *

   *  0e8f:0003 "GASIA USB Gamepad"

   *   - another version of the König gamepad

   *
   *  Copyright (c) 2007, 2009 Anssi Hannula <anssi.hannula@gmail.com>

   */
  
  /*
   * 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; either version 2 of the License, or
   * (at your option) any later version.
   *
   * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   */
  
  
  /* #define DEBUG */
  
  #define debug(format, arg...) pr_debug("hid-plff: " format "
  " , ## arg)
  
  #include <linux/input.h>

  #include <linux/slab.h>

  #include <linux/module.h>

  #include <linux/usb.h>
  #include <linux/hid.h>

  
  #include "hid-ids.h"
  
  #ifdef CONFIG_PANTHERLORD_FF
  #include "usbhid/usbhid.h"

  
  struct plff_device {
  	struct hid_report *report;

  	s32 *strong;
  	s32 *weak;

  };
  
  static int hid_plff_play(struct input_dev *dev, void *data,
  			 struct ff_effect *effect)
  {

  	struct hid_device *hid = input_get_drvdata(dev);

  	struct plff_device *plff = data;
  	int left, right;
  
  	left = effect->u.rumble.strong_magnitude;
  	right = effect->u.rumble.weak_magnitude;
  	debug("called with 0x%04x 0x%04x", left, right);
  
  	left = left * 0x7f / 0xffff;
  	right = right * 0x7f / 0xffff;

  	*plff->strong = left;
  	*plff->weak = right;

  	debug("running with 0x%02x 0x%02x", left, right);
  	usbhid_submit_report(hid, plff->report, USB_DIR_OUT);
  
  	return 0;
  }

  static int plff_init(struct hid_device *hid)

  {
  	struct plff_device *plff;
  	struct hid_report *report;
  	struct hid_input *hidinput;
  	struct list_head *report_list =
  			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
  	struct list_head *report_ptr = report_list;
  	struct input_dev *dev;
  	int error;

  	s32 *strong;
  	s32 *weak;

  	/* The device contains one output report per physical device, all
  	   containing 1 field, which contains 4 ff00.0002 usages and 4 16bit
  	   absolute values.

  	   The input reports also contain a field which contains

  	   8 ff00.0001 usages and 8 boolean values. Their meaning is

  	   currently unknown.
  	   
  	   A version of the 0e8f:0003 exists that has all the values in
  	   separate fields and misses the extra input field, thus resembling
  	   Zeroplus (hid-zpff) devices.
  	*/

  
  	if (list_empty(report_list)) {

  		hid_err(hid, "no output reports found
  ");

  		return -ENODEV;
  	}
  
  	list_for_each_entry(hidinput, &hid->inputs, list) {
  
  		report_ptr = report_ptr->next;
  
  		if (report_ptr == report_list) {

  			hid_err(hid, "required output report is missing
  ");

  			return -ENODEV;
  		}
  
  		report = list_entry(report_ptr, struct hid_report, list);
  		if (report->maxfield < 1) {

  			hid_err(hid, "no fields in the report
  ");

  			return -ENODEV;
  		}

  		if (report->field[0]->report_count >= 4) {
  			report->field[0]->value[0] = 0x00;
  			report->field[0]->value[1] = 0x00;
  			strong = &report->field[0]->value[2];
  			weak = &report->field[0]->value[3];
  			debug("detected single-field device");
  		} else if (report->maxfield >= 4 && report->field[0]->maxusage == 1 &&
  				report->field[0]->usage[0].hid == (HID_UP_LED | 0x43)) {
  			report->field[0]->value[0] = 0x00;
  			report->field[1]->value[0] = 0x00;
  			strong = &report->field[2]->value[0];
  			weak = &report->field[3]->value[0];
  			debug("detected 4-field device");
  		} else {

  			hid_err(hid, "not enough fields or values
  ");

  			return -ENODEV;
  		}
  
  		plff = kzalloc(sizeof(struct plff_device), GFP_KERNEL);
  		if (!plff)
  			return -ENOMEM;
  
  		dev = hidinput->input;
  
  		set_bit(FF_RUMBLE, dev->ffbit);
  
  		error = input_ff_create_memless(dev, plff, hid_plff_play);
  		if (error) {
  			kfree(plff);
  			return error;
  		}
  
  		plff->report = report;

  		plff->strong = strong;
  		plff->weak = weak;
  
  		*strong = 0x00;
  		*weak = 0x00;

  		usbhid_submit_report(hid, plff->report, USB_DIR_OUT);
  	}

  	hid_info(hid, "Force feedback for PantherLord/GreenAsia devices by Anssi Hannula <anssi.hannula@gmail.com>
  ");

  
  	return 0;
  }

  #else
  static inline int plff_init(struct hid_device *hid)
  {
  	return 0;
  }
  #endif
  
  static int pl_probe(struct hid_device *hdev, const struct hid_device_id *id)
  {
  	int ret;
  
  	if (id->driver_data)
  		hdev->quirks |= HID_QUIRK_MULTI_INPUT;
  
  	ret = hid_parse(hdev);
  	if (ret) {

  		hid_err(hdev, "parse failed
  ");

  		goto err;
  	}
  
  	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
  	if (ret) {

  		hid_err(hdev, "hw start failed
  ");

  		goto err;
  	}
  
  	plff_init(hdev);
  
  	return 0;
  err:
  	return ret;
  }
  
  static const struct hid_device_id pl_devices[] = {
  	{ HID_USB_DEVICE(USB_VENDOR_ID_GAMERON, USB_DEVICE_ID_GAMERON_DUAL_PSX_ADAPTOR),
  		.driver_data = 1 }, /* Twin USB Joystick */

  	{ HID_USB_DEVICE(USB_VENDOR_ID_GAMERON, USB_DEVICE_ID_GAMERON_DUAL_PCS_ADAPTOR),
  		.driver_data = 1 }, /* Twin USB Joystick */

  	{ HID_USB_DEVICE(USB_VENDOR_ID_GREENASIA, 0x0003), },

  	{ }
  };
  MODULE_DEVICE_TABLE(hid, pl_devices);
  
  static struct hid_driver pl_driver = {
  	.name = "pantherlord",
  	.id_table = pl_devices,
  	.probe = pl_probe,
  };

  static int __init pl_init(void)

  {
  	return hid_register_driver(&pl_driver);
  }

  static void __exit pl_exit(void)

  {
  	hid_unregister_driver(&pl_driver);
  }
  
  module_init(pl_init);
  module_exit(pl_exit);
  MODULE_LICENSE("GPL");