Subject: USB: usbnet (9/9) module for pl2301/2302 cables

From: David Brownell <[email-masked]>
Date: Sat, 13 Aug 2005 14:19:32 -0700

This should still be bug-compatible with the Linux 2.2 code, but
it'd be nice if someone finally sorted out the handshaking issues.
This wraps up the conversion of the "usbnet" driver structure, by
moving the Prolific PL-2201/2302 minidriver to a module of its own.
It also includes some minor cleanups to the remaining "usbnet" file,
notably removing that long changelog at the top.

Minor historical note:  Linux 2.2 first called the driver for
this hardware "plusb".

Signed-off-by: David Brownell <[email-masked]>
Signed-off-by: Greg Kroah-Hartman <[email-masked]>

---
 drivers/usb/net/Kconfig  |   24 ++---
 drivers/usb/net/Makefile |    1 
 drivers/usb/net/plusb.c  |  155 +++++++++++++++++++++++++++++++++
 drivers/usb/net/usbnet.c |  218 ++---------------------------------------------
 4 files changed, 179 insertions(+), 219 deletions(-)

--- gregkh-2.6.orig/drivers/usb/net/Makefile	2005-08-15 17:51:26.000000000 -0700
+++ gregkh-2.6/drivers/usb/net/Makefile	2005-08-15 17:51:27.000000000 -0700
@@ -10,6 +10,7 @@
 obj-$(CONFIG_USB_NET_CDCETHER)	+= cdc_ether.o
 obj-$(CONFIG_USB_NET_GL620A)	+= gl620a.o
 obj-$(CONFIG_USB_NET_NET1080)	+= net1080.o
+obj-$(CONFIG_USB_NET_PLUSB)	+= plusb.o
 obj-$(CONFIG_USB_NET_RNDIS)	+= rndis.o
 obj-$(CONFIG_USB_NET_SIMPLE)	+= simple.o
 obj-$(CONFIG_USB_NET_ZAURUS)	+= zaurus.o
--- gregkh-2.6.orig/drivers/usb/net/Kconfig	2005-08-15 17:51:26.000000000 -0700
+++ gregkh-2.6/drivers/usb/net/Kconfig	2005-08-15 17:51:27.000000000 -0700
@@ -125,20 +125,6 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called usbnet.
 
-comment "USB Host-to-Host Cables"
-	depends on USB_USBNET
-
-config USB_PL2301
-	boolean "Prolific PL-2301/2302 based cables"
-	default y
-	# handshake/init/reset problems, from original 'plusb' driver
-	depends on USB_USBNET && EXPERIMENTAL
-	help
-	  Choose this option if you're using a host-to-host cable
-	  with one of these chips.
-
-comment "Drivers built using the usbnet core"
-
 config USB_NET_AX8817X
 	tristate "ASIX AX88xxx Based USB 2.0 Ethernet Devices"
 	depends on USB_USBNET && NET_ETHERNET
@@ -213,6 +199,16 @@
 	  on this design:  one NetChip 1080 chips and supporting logic,
 	  supporting LEDs that indicate traffic
 
+config USB_NET_PLUSB
+	tristate "Prolific PL-2301/2302 based cables"
+	default y
+	# handshake/init/reset problems, from original 'plusb' driver
+	# if they're ever resolved, remove "experimental"
+	depends on USB_USBNET && EXPERIMENTAL
+	help
+	  Choose this option if you're using a host-to-host cable
+	  with one of these chips.
+
 config USB_NET_RNDIS
 	tristate "RNDIS devices (EXPERIMENTAL)"
 	depends on USB_USBNET && EXPERIMENTAL
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ gregkh-2.6/drivers/usb/net/plusb.c	2005-08-15 17:51:27.000000000 -0700
@@ -0,0 +1,155 @@
+/*
+ * PL-2301/2302 USB host-to-host link cables
+ * Copyright (C) 2000-2005 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+// #define	DEBUG			// error path messages, extra info
+// #define	VERBOSE			// more; success messages
+
+#include <linux/config.h>
+#ifdef	CONFIG_USB_DEBUG
+#   define DEBUG
+#endif
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/workqueue.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+
+#include "usbnet.h"
+
+
+/*
+ * Prolific PL-2301/PL-2302 driver ... http://www.prolifictech.com
+ *
+ * The protocol and handshaking used here should be bug-compatible
+ * with the Linux 2.2 "plusb" driver, by Deti Fliegl.
+ *
+ * HEADS UP:  that handshaking isn't all that robust.  This driver
+ * gets confused easily if you unplug one end of the cable then
+ * try to connect it again; you'll need to restart both ends. The
+ * "naplink" software (used by some PlayStation/2 deveopers) does
+ * the handshaking much better!   Also, sometimes this hardware
+ * seems to get wedged under load; it's likely that smarter code
+ * would fix that problem too.
+ */
+
+/*
+ * Bits 0-4 can be used for software handshaking; they're set from
+ * one end, cleared from the other, "read" with the interrupt byte.
+ */
+#define	PL_S_EN		(1<<7)		/* (feature only) suspend enable */
+/* reserved bit -- rx ready (6) ? */
+#define	PL_TX_READY	(1<<5)		/* (interrupt only) transmit ready */
+#define	PL_RESET_OUT	(1<<4)		/* reset output pipe */
+#define	PL_RESET_IN	(1<<3)		/* reset input pipe */
+#define	PL_TX_C		(1<<2)		/* transmission complete */
+#define	PL_TX_REQ	(1<<1)		/* transmission received */
+#define	PL_PEER_E	(1<<0)		/* peer exists */
+
+static inline int
+pl_vendor_req(struct usbnet *dev, u8 req, u8 val, u8 index)
+{
+	return usb_control_msg(dev->udev,
+		usb_rcvctrlpipe(dev->udev, 0),
+		req,
+		USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+		val, index,
+		NULL, 0,
+		USB_CTRL_GET_TIMEOUT);
+}
+
+static inline int
+pl_clear_QuickLink_features(struct usbnet *dev, int val)
+{
+	return pl_vendor_req(dev, 1, (u8) val, 0);
+}
+
+static inline int
+pl_set_QuickLink_features(struct usbnet *dev, int val)
+{
+	return pl_vendor_req(dev, 3, (u8) val, 0);
+}
+
+static int pl_reset(struct usbnet *dev)
+{
+	/* some units seem to need this reset, others reject it utterly.
+	 * FIXME be more like "naplink" or windows drivers.
+	 */
+	(void) pl_set_QuickLink_features(dev,
+		PL_S_EN|PL_RESET_OUT|PL_RESET_IN|PL_PEER_E);
+	return 0;
+}
+
+static const struct driver_info	prolific_info = {
+	.description =	"Prolific PL-2301/PL-2302",
+	.flags =	FLAG_NO_SETINT,
+		/* some PL-2302 versions seem to fail usb_set_interface() */
+	.reset =	pl_reset,
+};
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Proilific's name won't normally be on the cables, and
+ * may not be on the device.
+ */
+
+static const struct usb_device_id	products [] = {
+
+{
+	USB_DEVICE(0x067b, 0x0000),	// PL-2301
+	.driver_info =	(unsigned long) &prolific_info,
+}, {
+	USB_DEVICE(0x067b, 0x0001),	// PL-2302
+	.driver_info =	(unsigned long) &prolific_info,
+},
+
+	{ },		// END
+};
+MODULE_DEVICE_TABLE(usb, products);
+
+static struct usb_driver plusb_driver = {
+	.owner =	THIS_MODULE,
+	.name =		"plusb",
+	.id_table =	products,
+	.probe =	usbnet_probe,
+	.disconnect =	usbnet_disconnect,
+	.suspend =	usbnet_suspend,
+	.resume =	usbnet_resume,
+};
+
+static int __init plusb_init(void)
+{
+ 	return usb_register(&plusb_driver);
+}
+module_init(plusb_init);
+
+static void __exit plusb_exit(void)
+{
+ 	usb_deregister(&plusb_driver);
+}
+module_exit(plusb_exit);
+
+MODULE_AUTHOR("David Brownell");
+MODULE_DESCRIPTION("Prolific PL-2301/2302 USB Host to Host Link Driver");
+MODULE_LICENSE("GPL");
--- gregkh-2.6.orig/drivers/usb/net/usbnet.c	2005-08-15 17:51:26.000000000 -0700
+++ gregkh-2.6/drivers/usb/net/usbnet.c	2005-08-15 17:51:27.000000000 -0700
@@ -1,5 +1,5 @@
 /*
- * USB Networking Links
+ * USB Network driver infrastructure
  * Copyright (C) 2000-2005 by David Brownell
  * Copyright (C) 2003-2005 David Hollis <[email-masked]>
  *
@@ -20,96 +20,11 @@
 
 /*
  * This is a generic "USB networking" framework that works with several
- * kinds of full and high speed networking devices:
- *
- *   + USB host-to-host "network cables", used for IP-over-USB links.
- *     These are often used for Laplink style connectivity products.
- *	- AnchorChip 2720
- *	- Belkin, eTEK (interops with Win32 drivers)
- *	- GeneSys GL620USB-A
- *	- NetChip 1080 (interoperates with NetChip Win32 drivers)
- *	- Prolific PL-2301/2302 (replaces "plusb" driver)
- *	- KC Technology KC2190
- *
- *   + Smart USB devices can support such links directly, using Internet
- *     standard protocols instead of proprietary host-to-device links.
- *	- Linux PDAs like iPaq, Yopy, and Zaurus
- *	- The BLOB boot loader (for diskless booting)
- *	- Linux "gadgets", perhaps using PXA-2xx or Net2280 controllers
- *	- Devices using EPSON's sample USB firmware
- *	- CDC-Ethernet class devices, such as many cable modems
- *
- *   + Adapters to networks such as Ethernet.
- *	- AX8817X based USB 2.0 products
- *
- * Links to these devices can be bridged using Linux Ethernet bridging.
- * With minor exceptions, these all use similar USB framing for network
- * traffic, but need different protocols for control traffic.
- *
- * 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 SA1110, Zaurus, or EPSON device/client support in this driver;
- * slave/target drivers such as "usb-eth" (on most SA-1100 PDAs) or
- * "g_ether" (in the Linux "gadget" framework) implement that behavior
- * within devices.
- *
- *
- * CHANGELOG:
- *
- * 13-sep-2000	experimental, new
- * 10-oct-2000	usb_device_id table created. 
- * 28-oct-2000	misc fixes; mostly, discard more TTL-mangled rx packets.
- * 01-nov-2000	usb_device_id table and probing api update by
- *		Adam J. Richter <[email-masked]>.
- * 18-dec-2000	(db) tx watchdog, "net1080" renaming to "usbnet", device_info
- *		and prolific support, isolate net1080-specific bits, cleanup.
- *		fix unlink_urbs oops in D3 PM resume code path.
- *
- * 02-feb-2001	(db) fix tx skb sharing, packet length, match_flags, ...
- * 08-feb-2001	stubbed in "linuxdev", maybe the SA-1100 folk can use it;
- *		AnchorChips 2720 support (from spec) for testing;
- *		fix bit-ordering problem with ethernet multicast addr
- * 19-feb-2001  Support for clearing halt conditions. SA1100 UDC support
- *		updates. Oleg Drokin ([email-masked])
- * 25-mar-2001	More SA-1100 updates, including workaround for ip problem
- *		expecting cleared skb->cb and framing change to match latest
- *		handhelds.org version (Oleg).  Enable device IDs from the
- *		Win32 Belkin driver; other cleanups (db).
- * 16-jul-2001	Bugfixes for uhci oops-on-unplug, Belkin support, various
- *		cleanups for problems not yet seen in the field. (db)
- * 17-oct-2001	Handle "Advance USBNET" product, like Belkin/eTEK devices,
- *		from Ioannis Mavroukakis <[email-masked]>;
- *		rx unlinks somehow weren't async; minor cleanup.
- * 03-nov-2001	Merged GeneSys driver; original code from Jiun-Jie Huang
- *		<[email-masked]>, updated by Stanislav Brabec
- *		<[email-masked]>.  Made framing options (NetChip/GeneSys)
- *		tie mostly to (sub)driver info.  Workaround some PL-2302
- *		chips that seem to reject SET_INTERFACE requests.
- *
- * 06-apr-2002	Added ethtool support, based on a patch from Brad Hards.
- *		Level of diagnostics is more configurable; they use device
- *		location (usb_device->devpath) instead of address (2.5).
- *		For tx_fixup, memflags can't be NOIO.
- * 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).
- * 14-dec-2002	Remove Zaurus-private crc32 code (Pavel); 2.5 oops fix,
- * 		cleanups and stubbed PXA-250 support (db), fix for framing
- * 		issues on Z, net1080, and gl620a (Toby Milne)
- *
- * 31-mar-2003	Use endpoint descriptors:  high speed support, simpler sa1100
- * 		vs pxa25x, and CDC Ethernet.  Throttle down log floods on
- * 		disconnect; other cleanups. (db)  Flush net1080 fifos
- * 		after several sequential framing errors. (Johannes Erdfelt)
- * 22-aug-2003	AX8817X support (Dave Hollis).
- *
- * 14-jun-2004  Trivial patch for AX8817X based Buffalo LUA-U2-KTX in Japan
- *		(Neil Bortnak)
- * 03-nov-2004	Trivial patch for KC2190 (KC-190) chip. (Jonathan McDowell)
- *
- * 01-feb-2005	AX88772 support (Phil Chang & Dave Hollis)
- *-------------------------------------------------------------------------*/
+ * kinds of full and high speed networking devices:  host-to-host cables,
+ * smart usb peripherals, and actual Ethernet adapters.  These devices
+ * usually differ in terms of control protocol, and sometimes they define
+ * new framing to wrap their Ethernet packets.
+ */
 
 // #define	DEBUG			// error path messages, extra info
 // #define	VERBOSE			// more; success messages
@@ -298,77 +213,6 @@
 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 
 
-#ifdef CONFIG_USB_PL2301
-#define	HAVE_HARDWARE
-
-/*-------------------------------------------------------------------------
- *
- * Prolific PL-2301/PL-2302 driver ... http://www.prolifictech.com
- *
- * The protocol and handshaking used here should be bug-compatible
- * with the Linux 2.2 "plusb" driver, by Deti Fliegl.
- *
- *-------------------------------------------------------------------------*/
-
-/*
- * Bits 0-4 can be used for software handshaking; they're set from
- * one end, cleared from the other, "read" with the interrupt byte.
- */
-#define	PL_S_EN		(1<<7)		/* (feature only) suspend enable */
-/* reserved bit -- rx ready (6) ? */
-#define	PL_TX_READY	(1<<5)		/* (interrupt only) transmit ready */
-#define	PL_RESET_OUT	(1<<4)		/* reset output pipe */
-#define	PL_RESET_IN	(1<<3)		/* reset input pipe */
-#define	PL_TX_C		(1<<2)		/* transmission complete */
-#define	PL_TX_REQ	(1<<1)		/* transmission received */
-#define	PL_PEER_E	(1<<0)		/* peer exists */
-
-static inline int
-pl_vendor_req (struct usbnet *dev, u8 req, u8 val, u8 index)
-{
-	return usb_control_msg (dev->udev,
-		usb_rcvctrlpipe (dev->udev, 0),
-		req,
-		USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
-		val, index,
-		NULL, 0,
-		CONTROL_TIMEOUT_MS);
-}
-
-static inline int
-pl_clear_QuickLink_features (struct usbnet *dev, int val)
-{
-	return pl_vendor_req (dev, 1, (u8) val, 0);
-}
-
-static inline int
-pl_set_QuickLink_features (struct usbnet *dev, int val)
-{
-	return pl_vendor_req (dev, 3, (u8) val, 0);
-}
-
-/*-------------------------------------------------------------------------*/
-
-static int pl_reset (struct usbnet *dev)
-{
-	/* some units seem to need this reset, others reject it utterly.
-	 * FIXME be more like "naplink" or windows drivers.
-	 */
-	(void) pl_set_QuickLink_features (dev,
-		PL_S_EN|PL_RESET_OUT|PL_RESET_IN|PL_PEER_E);
-	return 0;
-}
-
-static const struct driver_info	prolific_info = {
-	.description =	"Prolific PL-2301/PL-2302",
-	.flags =	FLAG_NO_SETINT,
-		/* some PL-2302 versions seem to fail usb_set_interface() */
-	.reset =	pl_reset,
-};
-
-#endif /* CONFIG_USB_PL2301 */
-
-
 /*-------------------------------------------------------------------------
  *
  * Network Device Driver (peer link to "Host Device", from USB host)
@@ -1152,7 +996,8 @@
 	xdev = interface_to_usbdev (intf);
 
 	if (netif_msg_probe (dev))
-		devinfo (dev, "unregister usbnet usb-%s-%s, %s",
+		devinfo (dev, "unregister '%s' usb-%s-%s, %s",
+			driver_of(intf)->name,
 			xdev->bus->bus_name, xdev->devpath,
 			dev->driver_info->description);
 	
@@ -1280,8 +1125,9 @@
 	if (status)
 		goto out3;
 	if (netif_msg_probe (dev))
-		devinfo (dev, "register usbnet at usb-%s-%s, %s, "
+		devinfo (dev, "register '%s' at usb-%s-%s, %s, "
 				"%02x:%02x:%02x:%02x:%02x:%02x",
+			driver_of(udev)->name,
 			xdev->bus->bus_name, xdev->devpath,
 			dev->driver_info->description,
 			net->dev_addr [0], net->dev_addr [1],
@@ -1338,60 +1184,22 @@
 
 /*-------------------------------------------------------------------------*/
 
-#ifndef	HAVE_HARDWARE
-#error You need to configure some hardware for this driver
-#endif
-
-/*
- * chip vendor names won't normally be on the cables, and
- * may not be on the device.
- */
-
-static const struct usb_device_id	products [] = {
-
-#ifdef CONFIG_USB_PL2301
-{
-	USB_DEVICE (0x067b, 0x0000),	// PL-2301
-	.driver_info =	(unsigned long) &prolific_info,
-}, {
-	USB_DEVICE (0x067b, 0x0001),	// PL-2302
-	.driver_info =	(unsigned long) &prolific_info,
-},
-#endif
-	{ },		// END
-};
-MODULE_DEVICE_TABLE (usb, products);
-
-static struct usb_driver usbnet_driver = {
-	.owner =	THIS_MODULE,
-	.name =		driver_name,
-	.id_table =	products,
-	.probe =	usbnet_probe,
-	.disconnect =	usbnet_disconnect,
-	.suspend =	usbnet_suspend,
-	.resume =	usbnet_resume,
-};
-
-/*-------------------------------------------------------------------------*/
-
 static int __init usbnet_init(void)
 {
-	// compiler should optimize these out
+	/* compiler should optimize this out */
 	BUG_ON (sizeof (((struct sk_buff *)0)->cb)
 			< sizeof (struct skb_data));
 
 	random_ether_addr(node_id);
-
- 	return usb_register(&usbnet_driver);
+ 	return 0;
 }
 module_init(usbnet_init);
 
 static void __exit usbnet_exit(void)
 {
- 	usb_deregister(&usbnet_driver);
 }
 module_exit(usbnet_exit);
 
 MODULE_AUTHOR("David Brownell");
-MODULE_DESCRIPTION("USB Host-to-Host Link Drivers (numerous vendors)");
+MODULE_DESCRIPTION("USB network driver framework");
 MODULE_LICENSE("GPL");