text: /*
   *  Force feedback support for Zeroplus based devices
   *
   *  Copyright (c) 2005, 2006 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
   */
  
  
  #include <linux/hid.h>
  #include <linux/input.h>
  #include <linux/slab.h>
  #include <linux/usb.h>
  
  #include "hid-ids.h"
  
  #ifdef CONFIG_ZEROPLUS_FF
  #include "usbhid/usbhid.h"
  
  struct zpff_device {
  	struct hid_report *report;
  };
  
  static int zpff_play(struct input_dev *dev, void *data,
  			 struct ff_effect *effect)
  {
  	struct hid_device *hid = input_get_drvdata(dev);
  	struct zpff_device *zpff = data;
  	int left, right;
  
  	/*
  	 * The following is specified the other way around in the Zeroplus
  	 * datasheet but the order below is correct for the XFX Executioner;
  	 * however it is possible that the XFX Executioner is an exception
  	 */
  
  	left = effect->u.rumble.strong_magnitude;
  	right = effect->u.rumble.weak_magnitude;
  	dbg_hid("called with 0x%04x 0x%04x\n", left, right);
  
  	left = left * 0x7f / 0xffff;
  	right = right * 0x7f / 0xffff;
  
  	zpff->report->field[2]->value[0] = left;
  	zpff->report->field[3]->value[0] = right;
  	dbg_hid("running with 0x%02x 0x%02x\n", left, right);
  	usbhid_submit_report(hid, zpff->report, USB_DIR_OUT);
  
  	return 0;
  }
  
  static int zpff_init(struct hid_device *hid)
  {
  	struct zpff_device *zpff;
  	struct hid_report *report;
  	struct hid_input *hidinput = list_entry(hid->inputs.next,
  						struct hid_input, list);
  	struct list_head *report_list =
  			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
  	struct input_dev *dev = hidinput->input;
  	int error;
  
  	if (list_empty(report_list)) {
  		dev_err(&hid->dev, "no output report found\n");
  		return -ENODEV;
  	}
  
  	report = list_entry(report_list->next, struct hid_report, list);
  
  	if (report->maxfield < 4) {
  		dev_err(&hid->dev, "not enough fields in report\n");
  		return -ENODEV;
  	}
  
  	zpff = kzalloc(sizeof(struct zpff_device), GFP_KERNEL);
  	if (!zpff)
  		return -ENOMEM;
  
  	set_bit(FF_RUMBLE, dev->ffbit);
  
  	error = input_ff_create_memless(dev, zpff, zpff_play);
  	if (error) {
  		kfree(zpff);
  		return error;
  	}
  
  	zpff->report = report;
  	zpff->report->field[0]->value[0] = 0x00;
  	zpff->report->field[1]->value[0] = 0x02;
  	zpff->report->field[2]->value[0] = 0x00;
  	zpff->report->field[3]->value[0] = 0x00;
  	usbhid_submit_report(hid, zpff->report, USB_DIR_OUT);
  
  	dev_info(&hid->dev, "force feedback for Zeroplus based devices by "
  	       "Anssi Hannula <anssi.hannula@gmail.com>\n");
  
  	return 0;
  }
  #else
  static inline int zpff_init(struct hid_device *hid)
  {
  	return 0;
  }
  #endif
  
  static int zp_probe(struct hid_device *hdev, const struct hid_device_id *id)
  {
  	int ret;
  
  	ret = hid_parse(hdev);
  	if (ret) {
  		dev_err(&hdev->dev, "parse failed\n");
  		goto err;
  	}
  
  	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
  	if (ret) {
  		dev_err(&hdev->dev, "hw start failed\n");
  		goto err;
  	}
  
  	zpff_init(hdev);
  
  	return 0;
  err:
  	return ret;
  }
  
  static const struct hid_device_id zp_devices[] = {
  	{ HID_USB_DEVICE(USB_VENDOR_ID_ZEROPLUS, 0x0005) },
  	{ HID_USB_DEVICE(USB_VENDOR_ID_ZEROPLUS, 0x0030) },
  	{ }
  };
  MODULE_DEVICE_TABLE(hid, zp_devices);
  
  static struct hid_driver zp_driver = {
  	.name = "zeroplus",
  	.id_table = zp_devices,
  	.probe = zp_probe,
  };
  
  static int __init zp_init(void)
  {
  	return hid_register_driver(&zp_driver);
  }
  
  static void __exit zp_exit(void)
  {
  	hid_unregister_driver(&zp_driver);
  }
  
  module_init(zp_init);
  module_exit(zp_exit);
  MODULE_LICENSE("GPL");
  