[PATCH] usbnet, preliminary zaurus support

This is Pavel's patch, with some cleanups and re-sorting of
the various SA-1100 cases.  According to Pavel this works
as well as his earlier version ... which is to say, maybe
not yet, he saw a uhci "very bad" error (on 2.5.43).

I'm sending it along since it's clearly the right way to
support the Zaurus, and it can't be that far off given the
code I've seen.

drivers/usb/net/usbnet.c

 /*
  * USB Host-to-Host Links
  * Copyright (C) 2000-2002 by David Brownell <dbrownell@users.sourceforge.net>
+ * Copyright (C) 2002 Pavel Machek <pavel@ucw.cz>
+ *
+ * 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
  */
 
 /*
@@ -18,13 +33,15 @@
  *	- Belkin, eTEK (interops with Win32 drivers)
  *	- EPSON USB clients
  *	- GeneSys GL620USB-A
- *	- "Linux Devices" (like iPaq and similar SA-1100 based PDAs)
  *	- NetChip 1080 (interoperates with NetChip Win32 drivers)
  *	- Prolific PL-2301/2302 (replaces "plusb" driver)
+ *	- SA-1100 based Linux PDAs like iPaq, Yopy, and Zaurus
  *
  * USB devices can implement their side of this protocol at the cost
  * of two bulk endpoints; it's not restricted to "cable" applications.
- * See the LINUXDEV or EPSON device/client support.
+ * See the SA1110, Zaurus, or EPSON device/client support in this driver;
+ * slave/target drivers such as "usb-eth" (on most SA-1100 PDAs) are
+ * used inside USB slave/target devices.
  *
  * 
  * Status:
@@ -37,10 +54,6 @@
  *   handshaking; it'd be worth implementing those as "carrier detect".
  *   Prefer generic hooks, not minidriver-specific hacks.
  *
- * - Linux devices ... the www.handhelds.org SA-1100 support works nicely,
- *   but the Sharp Zaurus uses an incompatible protocol (extra checksums).
- *   No reason not to merge the Zaurus protocol here too (got patch? :)
- *
  * - For Netchip, should use keventd to poll via control requests to detect
  *   hardware level "carrier detect". 
  *
@@ -48,11 +61,14 @@
  *   sheets, sometimes it's not needed and sometimes it hangs.  Prolific has
  *   not responded to repeated support/information requests.
  *
+ * - SA-1100 PDAs ... the www.handhelds.org SA-1100 support works nicely.
+ *   Zaurus support has some problems; it's made UHCI die.
+ *
  * Interop with more Win32 drivers may be a good thing.
  *
  * Seems like reporting "peer connected" (carrier present) events may end
- * up going through the netlink event system, not hotplug ... that may be
- * awkward in terms of automatic configuration though.
+ * up going through the netlink event system, not hotplug ... so new links
+ * would likely be handled with a link monitoring thread in some daemon.
  *
  * There are reports that bridging gives lower-than-usual throughput.
  *
@@ -100,6 +116,7 @@
  * 07-may-2002	Generalize/cleanup keventd support, handling rx stalls (mostly
  *		for USB 2.0 TTs) and memory shortages (potential) too. (db)
  *		Use "locally assigned" IEEE802 address space. (Brad Hards)
+ * 18-oct-2002  Support for Zaurus (Pavel Machek), related cleanup (db).
  *
  *-------------------------------------------------------------------------*/
 
@@ -131,12 +148,13 @@
 #define	CONFIG_USB_BELKIN
 #define	CONFIG_USB_EPSON2888
 #define	CONFIG_USB_GENESYS
-#define	CONFIG_USB_LINUXDEV
 #define	CONFIG_USB_NET1080
 #define	CONFIG_USB_PL2301
+#define	CONFIG_USB_SA1110
+#define	CONFIG_USB_ZAURUS
 
 
-#define DRIVER_VERSION		"17-Jul-2002"
+#define DRIVER_VERSION		"18-Oct-2002"
 
 /*-------------------------------------------------------------------------*/
 
@@ -337,7 +355,7 @@ static const struct driver_info	belkin_info = {
  *
  * EPSON USB clients
  *
- * This is the same idea as "linuxdev" (below) except the firmware in the
+ * This is the same idea as Linux PDAs (below) except the firmware in the
  * device might not be Tux-powered.  Epson provides reference firmware that
  * implements this interface.  Product developers can reuse or modify that
  * code, such as by using their own product and vendor codes.
@@ -673,34 +691,6 @@ static const struct driver_info	genelink_info = {
 #endif /* CONFIG_USB_GENESYS */
 
 
-
-#ifdef	CONFIG_USB_LINUXDEV
-
-/*-------------------------------------------------------------------------
- *
- * This could talk to a device that uses Linux, such as a PDA or
- * an embedded system, or in fact to any "smart" device using this
- * particular mapping of USB and Ethernet.
- *
- * Such a Linux host would need a "USB Device Controller" hardware
- * (not "USB Host Controller"), and a network driver talking to that
- * hardware.
- *
- * One example is Intel's SA-1100 chip, which integrates basic USB
- * support (arch/arm/sa1100/usb-eth.c); it's used in the iPaq PDA.
- * And others too, like the Yopy.
- *
- *-------------------------------------------------------------------------*/
-
-static const struct driver_info	linuxdev_info = {
-	.description =	"Linux Device",
-
-	.in = 2, .out = 1,
-	.epsize = 64,
-};
-
-#endif	/* CONFIG_USB_LINUXDEV */
-
 
 #ifdef	CONFIG_USB_NET1080
 
@@ -1219,6 +1209,139 @@ static const struct driver_info	prolific_info = {
 #endif /* CONFIG_USB_PL2301 */
 
 
+
+#ifdef	CONFIG_USB_SA1100
+
+/*-------------------------------------------------------------------------
+ *
+ * Intel's SA-1100 chip integrates basic USB support, and is used
+ * in PDAs like some iPaqs, the Yopy, some Zaurus models, and more.
+ * When they runs Linux, arch/arm/sa1100/usb-eth.c may be used to
+ * network using minimal USB framing data.
+ *
+ * This describes the driver currently in www.handhelds.org kernels.
+ * The Zaurus uses a different driver (see later).
+ *
+ *-------------------------------------------------------------------------*/
+
+static const struct driver_info	linuxdev_info = {
+	.description =	"SA-1100 Linux Device",
+
+	.in = 2, .out = 1,
+	.epsize = 64,
+};
+
+static const struct driver_info	yopy_info = {
+	.description =	"Yopy",
+
+	.in = 2, .out = 1,
+	.epsize = 64,
+};
+
+#endif	/* CONFIG_USB_SA1100 */
+
+
+#ifdef CONFIG_USB_ZAURUS
+
+/*-------------------------------------------------------------------------
+ *
+ * Zaurus is also a SA-1110 based PDA, but one using a different driver
+ * for its USB slave/target controller than the case above.
+ *
+ * The key differences are that (a) it's got a msft-friendly configuration,
+ * and (b) the linux-friendly framing adds a crc32 to cope with some
+ * memory corruption observed with usb-to-memory DMA in some cases.
+ *
+ *-------------------------------------------------------------------------*/
+
+static const u32 crc32_table [256] = {
+    0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
+    0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
+    0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+    0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
+    0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
+    0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+    0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
+    0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
+    0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+    0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
+    0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
+    0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+    0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
+    0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
+    0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+    0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
+    0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
+    0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+    0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
+    0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
+    0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+    0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
+    0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
+    0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+    0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
+    0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
+    0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+    0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
+    0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
+    0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+    0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
+    0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
+};
+
+#define CRC32_INITFCS     0xffffffff  // Initial FCS value 
+#define CRC32_FCS(fcs, c) (((fcs) >> 8) ^ crc32_table[((fcs) ^ (c)) & 0xff])
+
+/* fcs_compute32 - memcpy and calculate fcs
+ * Perform a memcpy and calculate fcs using ppp 32bit CRC algorithm.
+ */
+static inline u32 fcs_compute32 (unsigned char *sp, int len, u32 fcs)
+{
+	for (;len-- > 0; fcs = CRC32_FCS (fcs, *sp++))
+		continue;
+	return fcs;
+}
+
+static struct sk_buff *
+zaurus_tx_fixup (struct usbnet *dev, struct sk_buff *skb, int 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 = fcs_compute32 (skb->data, skb->len, CRC32_INITFCS);
+		fcs = ~fcs;
+
+		// ? add optional byte make addr even ?
+
+		*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 const struct driver_info	zaurus_info = {
+	.description =	"Sharp Zaurus",
+	.tx_fixup = 	zaurus_tx_fixup,
+
+	.in = 2, .out = 1,
+	.epsize = 64,
+};
+#endif
+
 
 /*-------------------------------------------------------------------------
  *
@@ -2043,6 +2166,16 @@ usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
 		xdev->bus->bus_name, xdev->devpath,
 		dev->driver_info->description);
 
+#ifdef CONFIG_USB_ZAURUS
+	if (dev->driver_info == &zaurus_info) {
+		int	status;
+		status = usb_set_configuration (xdev, 1);
+		devinfo (dev, "set config --> %d", status);
+		status = usb_set_interface (xdev, 1, 1);
+		devinfo (dev, "set altsetting --> %d", status);
+	}
+#endif
+
 	// ok, it's ready to go.
 	dev_set_drvdata (&udev->dev, net);
 	mutex_lock (&usbnet_mutex);
@@ -2106,23 +2239,6 @@ static const struct usb_device_id	products [] = {
 	 */
 #endif
 
-#ifdef	CONFIG_USB_LINUXDEV
-/*
- * for example, this can be a host side talk-to-PDA driver.
- * this driver is NOT what runs _inside_ a Linux device !!
- */
-{
-	// 1183 = 0x049F, both used as hex values?
-	USB_DEVICE (0x049F, 0x505A),	// Compaq "Itsy"
-	.driver_info =	(unsigned long) &linuxdev_info,
-}, {
-	USB_DEVICE (0x0E7E, 0x1001),	// G.Mate "Yopy"
-	.driver_info =	(unsigned long) &linuxdev_info,
-},
-	// NOTE:  the Sharp Zaurus uses a modified version of
-	// this driver, which is not interoperable with this.
-#endif
-
 #ifdef	CONFIG_USB_NET1080
 {
 	USB_DEVICE (0x0525, 0x1080),	// NetChip ref design
@@ -2143,6 +2259,39 @@ static const struct usb_device_id	products [] = {
 },
 #endif
 
+#ifdef	CONFIG_USB_SA1100
+/*
+ * SA-1100 using www.handhelds.org kernels, or compatible.
+ * Often used when talking to Linux PDAs (iPaq, Yopy, etc).
+ * The sa-1100 "usb-eth" driver handles the basic framing.
+ */
+{
+	// 1183 = 0x049F, both used as hex values?
+	USB_DEVICE (0x049F, 0x505A),	// iPaq: Compaq "Itsy"
+	.driver_info =	(unsigned long) &linuxdev_info,
+}, {
+	USB_DEVICE (0x0E7E, 0x1001),	// G.Mate "Yopy"
+	.driver_info =	(unsigned long) &yopy_info,
+}, 
+#endif
+
+#ifdef	CONFIG_USB_ZAURUS
+/*
+ * SA-1100 based Sharp Zaurus ("collie"), or compatible.
+ * Same idea as above, but different framing.
+ */
+{
+	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
+			  | USB_DEVICE_ID_MATCH_DEVICE, 
+	.idVendor		= 0x04DD,
+	.idProduct		= 0x8004,
+	.bInterfaceClass	= 0x0a,
+	.bInterfaceSubClass	= 0x00,
+	.bInterfaceProtocol	= 0x00,
+	.driver_info =  (unsigned long) &zaurus_info,
+},
+#endif
+
 /* KC2190 from www.sepoong.co.kr "InstaNET" */
 
 	{ },		// END