/*
   * Copyright (C) 2002 Pavel Machek <pavel@ucw.cz>
   * Copyright (C) 2002-2005 by David Brownell
   *
   * 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, see <http://www.gnu.org/licenses/>.

   */
  
  // #define	DEBUG			// error path messages, extra info
  // #define	VERBOSE			// more; success messages

  #include <linux/module.h>

  #include <linux/netdevice.h>
  #include <linux/ethtool.h>
  #include <linux/workqueue.h>
  #include <linux/mii.h>
  #include <linux/crc32.h>
  #include <linux/usb.h>

  #include <linux/usb/cdc.h>

  #include <linux/usb/usbnet.h>

  
  
  /*
   * All known Zaurii lie about their standards conformance.  At least
   * the earliest SA-1100 models lie by saying they support CDC Ethernet.
   * Some later models (especially PXA-25x and PXA-27x based ones) lie
   * and say they support CDC MDLM (for access to cell phone modems).
   *
   * There are non-Zaurus products that use these same protocols too.
   *
   * The annoying thing is that at the same time Sharp was developing
   * that annoying standards-breaking software, the Linux community had
   * a simple "CDC Subset" working reliably on the same SA-1100 hardware.
   * That is, the same functionality but not violating standards.
   *
   * The CDC Ethernet nonconformance points are troublesome to hosts
   * with a true CDC Ethernet implementation:
   *   - Framing appends a CRC, which the spec says drivers "must not" do;
   *   - Transfers data in altsetting zero, instead of altsetting 1;
   *   - All these peripherals use the same ethernet address.
   *
   * The CDC MDLM nonconformance is less immediately troublesome, since all
   * MDLM implementations are quasi-proprietary anyway.
   */
  
  static struct sk_buff *

  zaurus_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)

  {
  	int			padlen;
  	struct sk_buff		*skb2;
  
  	padlen = 2;
  	if (!skb_cloned(skb)) {
  		int	tailroom = skb_tailroom(skb);
  		if ((padlen + 4) <= tailroom)
  			goto done;
  	}
  	skb2 = skb_copy_expand(skb, 0, 4 + padlen, flags);
  	dev_kfree_skb_any(skb);
  	skb = skb2;
  	if (skb) {
  		u32		fcs;
  done:
  		fcs = crc32_le(~0, skb->data, skb->len);
  		fcs = ~fcs;
  
  		*skb_put (skb, 1) = fcs       & 0xff;
  		*skb_put (skb, 1) = (fcs>> 8) & 0xff;
  		*skb_put (skb, 1) = (fcs>>16) & 0xff;
  		*skb_put (skb, 1) = (fcs>>24) & 0xff;
  	}
  	return skb;
  }
  
  static int zaurus_bind(struct usbnet *dev, struct usb_interface *intf)
  {
  	/* Belcarra's funky framing has other options; mostly
  	 * TRAILERS (!) with 4 bytes CRC, and maybe 2 pad bytes.
  	 */
  	dev->net->hard_header_len += 6;
  	dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu;
  	return usbnet_generic_cdc_bind(dev, intf);
  }
  
  /* PDA style devices are always connected if present */
  static int always_connected (struct usbnet *dev)
  {
  	return 0;
  }
  
  static const struct driver_info	zaurus_sl5x00_info = {
  	.description =	"Sharp Zaurus SL-5x00",

  	.flags =	FLAG_POINTTOPOINT | FLAG_FRAMING_Z,

  	.check_connect = always_connected,
  	.bind =		zaurus_bind,
  	.unbind =	usbnet_cdc_unbind,

  	.tx_fixup =	zaurus_tx_fixup,

  };
  #define	ZAURUS_STRONGARM_INFO	((unsigned long)&zaurus_sl5x00_info)
  
  static const struct driver_info	zaurus_pxa_info = {
  	.description =	"Sharp Zaurus, PXA-2xx based",

  	.flags =	FLAG_POINTTOPOINT | FLAG_FRAMING_Z,

  	.check_connect = always_connected,
  	.bind =		zaurus_bind,
  	.unbind =	usbnet_cdc_unbind,

  	.tx_fixup =	zaurus_tx_fixup,

  };
  #define	ZAURUS_PXA_INFO		((unsigned long)&zaurus_pxa_info)
  
  static const struct driver_info	olympus_mxl_info = {
  	.description =	"Olympus R1000",

  	.flags =	FLAG_POINTTOPOINT | FLAG_FRAMING_Z,

  	.check_connect = always_connected,
  	.bind =		zaurus_bind,
  	.unbind =	usbnet_cdc_unbind,

  	.tx_fixup =	zaurus_tx_fixup,

  };
  #define	OLYMPUS_MXL_INFO	((unsigned long)&olympus_mxl_info)
  
  
  /* Some more recent products using Lineo/Belcarra code will wrongly claim
   * CDC MDLM conformance.  They aren't conformant:  data endpoints live
   * in the control interface, there's no data interface, and it's not used
   * to talk to a cell phone radio.  But at least we can detect these two
   * pseudo-classes, rather than growing this product list with entries for
   * each new nonconformant product (sigh).
   */
  static const u8 safe_guid[16] = {
  	0x5d, 0x34, 0xcf, 0x66, 0x11, 0x18, 0x11, 0xd6,
  	0xa2, 0x1a, 0x00, 0x01, 0x02, 0xca, 0x9a, 0x7f,
  };
  static const u8 blan_guid[16] = {
  	0x74, 0xf0, 0x3d, 0xbd, 0x1e, 0xc1, 0x44, 0x70,
  	0xa3, 0x67, 0x71, 0x34, 0xc9, 0xf5, 0x54, 0x37,
  };
  
  static int blan_mdlm_bind(struct usbnet *dev, struct usb_interface *intf)
  {
  	u8				*buf = intf->cur_altsetting->extra;
  	int				len = intf->cur_altsetting->extralen;
  	struct usb_cdc_mdlm_desc	*desc = NULL;
  	struct usb_cdc_mdlm_detail_desc	*detail = NULL;
  
  	while (len > 3) {
  		if (buf [1] != USB_DT_CS_INTERFACE)
  			goto next_desc;
  
  		/* use bDescriptorSubType, and just verify that we get a
  		 * "BLAN" (or "SAFE") descriptor.
  		 */
  		switch (buf [2]) {
  		case USB_CDC_MDLM_TYPE:
  			if (desc) {
  				dev_dbg(&intf->dev, "extra MDLM
  ");
  				goto bad_desc;
  			}
  			desc = (void *) buf;
  			if (desc->bLength != sizeof *desc) {
  				dev_dbg(&intf->dev, "MDLM len %u
  ",
  					desc->bLength);
  				goto bad_desc;
  			}
  			/* expect bcdVersion 1.0, ignore */

  			if (memcmp(&desc->bGUID, blan_guid, 16) &&
  			    memcmp(&desc->bGUID, safe_guid, 16)) {

  				/* hey, this one might _really_ be MDLM! */
  				dev_dbg(&intf->dev, "MDLM guid
  ");
  				goto bad_desc;
  			}
  			break;
  		case USB_CDC_MDLM_DETAIL_TYPE:
  			if (detail) {
  				dev_dbg(&intf->dev, "extra MDLM detail
  ");
  				goto bad_desc;
  			}
  			detail = (void *) buf;
  			switch (detail->bGuidDescriptorType) {
  			case 0:			/* "SAFE" */
  				if (detail->bLength != (sizeof *detail + 2))
  					goto bad_detail;
  				break;
  			case 1:			/* "BLAN" */
  				if (detail->bLength != (sizeof *detail + 3))
  					goto bad_detail;
  				break;
  			default:
  				goto bad_detail;
  			}
  
  			/* assuming we either noticed BLAN already, or will
  			 * find it soon, there are some data bytes here:
  			 *  - bmNetworkCapabilities (unused)
  			 *  - bmDataCapabilities (bits, see below)
  			 *  - bPad (ignored, for PADAFTER -- BLAN-only)
  			 * bits are:
  			 *  - 0x01 -- Zaurus framing (add CRC)
  			 *  - 0x02 -- PADBEFORE (CRC includes some padding)
  			 *  - 0x04 -- PADAFTER (some padding after CRC)
  			 *  - 0x08 -- "fermat" packet mangling (for hw bugs)
  			 * the PADBEFORE appears not to matter; we interop
  			 * with devices that use it and those that don't.
  			 */
  			if ((detail->bDetailData[1] & ~0x02) != 0x01) {

  				/* bmDataCapabilities == 0 would be fine too,

  				 * but framing is minidriver-coupled for now.
  				 */
  bad_detail:
  				dev_dbg(&intf->dev,
  						"bad MDLM detail, %d %d %d
  ",
  						detail->bLength,
  						detail->bDetailData[0],
  						detail->bDetailData[2]);
  				goto bad_desc;
  			}

  
  			/* same extra framing as for non-BLAN mode */
  			dev->net->hard_header_len += 6;
  			dev->rx_urb_size = dev->net->hard_header_len
  					+ dev->net->mtu;

  			break;
  		}
  next_desc:
  		len -= buf [0];	/* bLength */
  		buf += buf [0];
  	}
  
  	if (!desc || !detail) {
  		dev_dbg(&intf->dev, "missing cdc mdlm %s%sdescriptor
  ",
  			desc ? "" : "func ",
  			detail ? "" : "detail ");
  		goto bad_desc;
  	}
  
  	/* There's probably a CDC Ethernet descriptor there, but we can't
  	 * rely on the Ethernet address it provides since not all vendors
  	 * bother to make it unique.  Likewise there's no point in tracking
  	 * of the CDC event notifications.
  	 */
  	return usbnet_get_endpoints(dev, intf);
  
  bad_desc:
  	dev_info(&dev->udev->dev, "unsupported MDLM descriptors
  ");
  	return -ENODEV;
  }
  
  static const struct driver_info	bogus_mdlm_info = {
  	.description =	"pseudo-MDLM (BLAN) device",

  	.flags =	FLAG_POINTTOPOINT | FLAG_FRAMING_Z,

  	.check_connect = always_connected,

  	.tx_fixup =	zaurus_tx_fixup,

  	.bind =		blan_mdlm_bind,
  };
  
  static const struct usb_device_id	products [] = {
  #define	ZAURUS_MASTER_INTERFACE \
  	.bInterfaceClass	= USB_CLASS_COMM, \
  	.bInterfaceSubClass	= USB_CDC_SUBCLASS_ETHERNET, \
  	.bInterfaceProtocol	= USB_CDC_PROTO_NONE
  
  /* SA-1100 based Sharp Zaurus ("collie"), or compatible. */
  {
  	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
  			  | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor		= 0x04DD,
  	.idProduct		= 0x8004,
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_STRONGARM_INFO,
  },
  
  /* PXA-2xx based models are also lying-about-cdc.  If you add any
   * more devices that claim to be CDC Ethernet, make sure they get
   * added to the blacklist in cdc_ether too.
   *
   * NOTE:  OpenZaurus versions with 2.6 kernels won't use these entries,
   * unlike the older ones with 2.4 "embedix" kernels.
   */
  {
  	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
  			  | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor		= 0x04DD,
  	.idProduct		= 0x8005,	/* A-300 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_PXA_INFO,
  }, {
  	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
  			  | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor		= 0x04DD,
  	.idProduct		= 0x8006,	/* B-500/SL-5600 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_PXA_INFO,
  }, {
  	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
  	          | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor		= 0x04DD,
  	.idProduct		= 0x8007,	/* C-700 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_PXA_INFO,
  }, {
  	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
  		 | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor               = 0x04DD,
  	.idProduct              = 0x9031,	/* C-750 C-760 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_PXA_INFO,
  }, {

  	/* C-750/C-760/C-860/SL-C3000 PDA in MDLM mode */
  	USB_DEVICE_AND_INTERFACE_INFO(0x04DD, 0x9031, USB_CLASS_COMM,
  			USB_CDC_SUBCLASS_MDLM, USB_CDC_PROTO_NONE),
  	.driver_info = (unsigned long) &bogus_mdlm_info,
  }, {

  	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
  		 | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor               = 0x04DD,
  	.idProduct              = 0x9032,	/* SL-6000 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_PXA_INFO,
  }, {
  	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
  		 | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor               = 0x04DD,
  	/* reported with some C860 units */
  	.idProduct              = 0x9050,	/* C-860 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = ZAURUS_PXA_INFO,
  },

  {

  	/* Motorola Rokr E6 */
  	USB_DEVICE_AND_INTERFACE_INFO(0x22b8, 0x6027, USB_CLASS_COMM,
  			USB_CDC_SUBCLASS_MDLM, USB_CDC_PROTO_NONE),
  	.driver_info = (unsigned long) &bogus_mdlm_info,
  }, {

  	/* Motorola MOTOMAGX phones */
  	USB_DEVICE_AND_INTERFACE_INFO(0x22b8, 0x6425, USB_CLASS_COMM,
  			USB_CDC_SUBCLASS_MDLM, USB_CDC_PROTO_NONE),
  	.driver_info = (unsigned long) &bogus_mdlm_info,

  },
  
  /* Olympus has some models with a Zaurus-compatible option.
   * R-1000 uses a FreeScale i.MXL cpu (ARMv4T)
   */
  {
  	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
  		 | USB_DEVICE_ID_MATCH_DEVICE,
  	.idVendor               = 0x07B4,
  	.idProduct              = 0x0F02,	/* R-1000 */
  	ZAURUS_MASTER_INTERFACE,
  	.driver_info = OLYMPUS_MXL_INFO,
  },

  
  /* Logitech Harmony 900 - uses the pseudo-MDLM (BLAN) driver */
  {
  	USB_DEVICE_AND_INTERFACE_INFO(0x046d, 0xc11f, USB_CLASS_COMM,
  			USB_CDC_SUBCLASS_MDLM, USB_CDC_PROTO_NONE),
  	.driver_info = (unsigned long) &bogus_mdlm_info,
  },

  	{ },		// END
  };
  MODULE_DEVICE_TABLE(usb, products);
  
  static struct usb_driver zaurus_driver = {

  	.name =		"zaurus",
  	.id_table =	products,
  	.probe =	usbnet_probe,
  	.disconnect =	usbnet_disconnect,
  	.suspend =	usbnet_suspend,
  	.resume =	usbnet_resume,

  	.disable_hub_initiated_lpm = 1,

  };

  module_usb_driver(zaurus_driver);

  
  MODULE_AUTHOR("Pavel Machek, David Brownell");
  MODULE_DESCRIPTION("Sharp Zaurus PDA, and compatible products");
  MODULE_LICENSE("GPL");