text: /*
   * IgorPlug-USB IR Receiver
   *
   * Copyright (C) 2014 Sean Young <sean@mess.org>
   *
   * Supports the standard homebrew IgorPlugUSB receiver with Igor's firmware.
   * See http://www.cesko.host.sk/IgorPlugUSB/IgorPlug-USB%20(AVR)_eng.htm
   *
   * Based on the lirc_igorplugusb.c driver:
   *	Copyright (C) 2004 Jan M. Hochstein
   *	<hochstein@algo.informatik.tu-darmstadt.de>
   *
   * 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.
   */
  #include <linux/device.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/usb.h>
  #include <linux/usb/input.h>
  #include <media/rc-core.h>
  
  #define DRIVER_DESC		"IgorPlug-USB IR Receiver"
  #define DRIVER_NAME		"igorplugusb"
  
  #define HEADERLEN		3
  #define BUFLEN			36
  #define MAX_PACKET		(HEADERLEN + BUFLEN)
  
  #define SET_INFRABUFFER_EMPTY	1
  #define GET_INFRACODE		2
  
  
  struct igorplugusb {
  	struct rc_dev *rc;
  	struct device *dev;
  
  	struct urb *urb;
  	struct usb_ctrlrequest request;
  
  	struct timer_list timer;
  
  	uint8_t buf_in[MAX_PACKET];
  
  	char phys[64];
  };
  
  static void igorplugusb_cmd(struct igorplugusb *ir, int cmd);
  
  static void igorplugusb_irdata(struct igorplugusb *ir, unsigned len)
  {
  	DEFINE_IR_RAW_EVENT(rawir);
  	unsigned i, start, overflow;
  
  	dev_dbg(ir->dev, "irdata: %*ph (len=%u)", len, ir->buf_in, len);
  
  	/*
  	 * If more than 36 pulses and spaces follow each other, the igorplugusb
  	 * overwrites its buffer from the beginning. The overflow value is the
  	 * last offset which was not overwritten. Everything from this offset
  	 * onwards occurred before everything until this offset.
  	 */
  	overflow = ir->buf_in[2];
  	i = start = overflow + HEADERLEN;
  
  	if (start >= len) {
  		dev_err(ir->dev, "receive overflow invalid: %u", overflow);
  	} else {
  		if (overflow > 0)
  			dev_warn(ir->dev, "receive overflow, at least %u lost",
  								overflow);
  
  		do {
  			rawir.duration = ir->buf_in[i] * 85333;
  			rawir.pulse = i & 1;
  
  			ir_raw_event_store_with_filter(ir->rc, &rawir);
  
  			if (++i == len)
  				i = HEADERLEN;
  		} while (i != start);
  
  		/* add a trailing space */
  		rawir.duration = ir->rc->timeout;
  		rawir.pulse = false;
  		ir_raw_event_store_with_filter(ir->rc, &rawir);
  
  		ir_raw_event_handle(ir->rc);
  	}
  
  	igorplugusb_cmd(ir, SET_INFRABUFFER_EMPTY);
  }
  
  static void igorplugusb_callback(struct urb *urb)
  {
  	struct usb_ctrlrequest *req;
  	struct igorplugusb *ir = urb->context;
  
  	req = (struct usb_ctrlrequest *)urb->setup_packet;
  
  	switch (urb->status) {
  	case 0:
  		if (req->bRequest == GET_INFRACODE &&
  					urb->actual_length > HEADERLEN)
  			igorplugusb_irdata(ir, urb->actual_length);
  		else /* request IR */
  			mod_timer(&ir->timer, jiffies + msecs_to_jiffies(50));
  		break;
  	case -EPROTO:
  	case -ECONNRESET:
  	case -ENOENT:
  	case -ESHUTDOWN:
  		usb_unlink_urb(urb);
  		return;
  	default:
  		dev_warn(ir->dev, "Error: urb status = %d\n", urb->status);
  		igorplugusb_cmd(ir, SET_INFRABUFFER_EMPTY);
  		break;
  	}
  }
  
  static void igorplugusb_cmd(struct igorplugusb *ir, int cmd)
  {
  	int ret;
  
  	ir->request.bRequest = cmd;
  	ir->urb->transfer_flags = 0;
  	ret = usb_submit_urb(ir->urb, GFP_ATOMIC);
  	if (ret)
  		dev_err(ir->dev, "submit urb failed: %d", ret);
  }
  
  static void igorplugusb_timer(unsigned long data)
  {
  	struct igorplugusb *ir = (struct igorplugusb *)data;
  
  	igorplugusb_cmd(ir, GET_INFRACODE);
  }
  
  static int igorplugusb_probe(struct usb_interface *intf,
  					const struct usb_device_id *id)
  {
  	struct usb_device *udev;
  	struct usb_host_interface *idesc;
  	struct usb_endpoint_descriptor *ep;
  	struct igorplugusb *ir;
  	struct rc_dev *rc;
  	int ret = -ENOMEM;
  
  	udev = interface_to_usbdev(intf);
  	idesc = intf->cur_altsetting;
  
  	if (idesc->desc.bNumEndpoints != 1) {
  		dev_err(&intf->dev, "incorrect number of endpoints");
  		return -ENODEV;
  	}
  
  	ep = &idesc->endpoint[0].desc;
  	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_control(ep)) {
  		dev_err(&intf->dev, "endpoint incorrect");
  		return -ENODEV;
  	}
  
  	ir = devm_kzalloc(&intf->dev, sizeof(*ir), GFP_KERNEL);
  	if (!ir)
  		return -ENOMEM;
  
  	ir->dev = &intf->dev;
  
  	setup_timer(&ir->timer, igorplugusb_timer, (unsigned long)ir);
  
  	ir->request.bRequest = GET_INFRACODE;
  	ir->request.bRequestType = USB_TYPE_VENDOR | USB_DIR_IN;
  	ir->request.wLength = cpu_to_le16(sizeof(ir->buf_in));
  
  	ir->urb = usb_alloc_urb(0, GFP_KERNEL);
  	if (!ir->urb)
  		goto fail;
  
  	usb_fill_control_urb(ir->urb, udev,
  		usb_rcvctrlpipe(udev, 0), (uint8_t *)&ir->request,
  		ir->buf_in, sizeof(ir->buf_in), igorplugusb_callback, ir);
  
  	usb_make_path(udev, ir->phys, sizeof(ir->phys));
  
  	rc = rc_allocate_device(RC_DRIVER_IR_RAW);
  	if (!rc)
  		goto fail;
  
  	rc->input_name = DRIVER_DESC;
  	rc->input_phys = ir->phys;
  	usb_to_input_id(udev, &rc->input_id);
  	rc->dev.parent = &intf->dev;
  	/*
  	 * This device can only store 36 pulses + spaces, which is not enough
  	 * for the NEC protocol and many others.
  	 */
  	rc->allowed_protocols = RC_BIT_ALL_IR_DECODER & ~(RC_BIT_NEC |
  			RC_BIT_NECX | RC_BIT_NEC32 | RC_BIT_RC6_6A_20 |
  			RC_BIT_RC6_6A_24 | RC_BIT_RC6_6A_32 | RC_BIT_RC6_MCE |
  			RC_BIT_SONY20 | RC_BIT_MCE_KBD | RC_BIT_SANYO);
  
  	rc->priv = ir;
  	rc->driver_name = DRIVER_NAME;
  	rc->map_name = RC_MAP_HAUPPAUGE;
  	rc->timeout = MS_TO_NS(100);
  	rc->rx_resolution = 85333;
  
  	ir->rc = rc;
  	ret = rc_register_device(rc);
  	if (ret) {
  		dev_err(&intf->dev, "failed to register rc device: %d", ret);
  		goto fail;
  	}
  
  	usb_set_intfdata(intf, ir);
  
  	igorplugusb_cmd(ir, SET_INFRABUFFER_EMPTY);
  
  	return 0;
  fail:
  	rc_free_device(ir->rc);
  	usb_free_urb(ir->urb);
  	del_timer(&ir->timer);
  
  	return ret;
  }
  
  static void igorplugusb_disconnect(struct usb_interface *intf)
  {
  	struct igorplugusb *ir = usb_get_intfdata(intf);
  
  	rc_unregister_device(ir->rc);
  	del_timer_sync(&ir->timer);
  	usb_set_intfdata(intf, NULL);
  	usb_kill_urb(ir->urb);
  	usb_free_urb(ir->urb);
  }
  
  static struct usb_device_id igorplugusb_table[] = {
  	/* Igor Plug USB (Atmel's Manufact. ID) */
  	{ USB_DEVICE(0x03eb, 0x0002) },
  	/* Fit PC2 Infrared Adapter */
  	{ USB_DEVICE(0x03eb, 0x21fe) },
  	/* Terminating entry */
  	{ }
  };
  
  static struct usb_driver igorplugusb_driver = {
  	.name =	DRIVER_NAME,
  	.probe = igorplugusb_probe,
  	.disconnect = igorplugusb_disconnect,
  	.id_table = igorplugusb_table
  };
  
  module_usb_driver(igorplugusb_driver);
  
  MODULE_DESCRIPTION(DRIVER_DESC);
  MODULE_AUTHOR("Sean Young <sean@mess.org>");
  MODULE_LICENSE("GPL");
  MODULE_DEVICE_TABLE(usb, igorplugusb_table);
  