1 /*
2 * PL-2301/2302 USB host-to-host link cables
3 * Copyright (C) 2000-2005 by David Brownell
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20 // #define DEBUG // error path messages, extra info
21 // #define VERBOSE // more; success messages
22
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/ethtool.h>
28 #include <linux/workqueue.h>
29 #include <linux/mii.h>
30 #include <linux/usb.h>
31 #include <linux/usb/usbnet.h>
32
33
34 /*
35 * Prolific PL-2301/PL-2302 driver ... http://www.prolifictech.com
36 *
37 * The protocol and handshaking used here should be bug-compatible
38 * with the Linux 2.2 "plusb" driver, by Deti Fliegl.
39 *
40 * HEADS UP: this handshaking isn't all that robust. This driver
41 * gets confused easily if you unplug one end of the cable then
42 * try to connect it again; you'll need to restart both ends. The
43 * "naplink" software (used by some PlayStation/2 deveopers) does
44 * the handshaking much better! Also, sometimes this hardware
45 * seems to get wedged under load. Prolific docs are weak, and
46 * don't identify differences between PL2301 and PL2302, much less
47 * anything to explain the different PL2302 versions observed.
48 */
49
50 /*
51 * Bits 0-4 can be used for software handshaking; they're set from
52 * one end, cleared from the other, "read" with the interrupt byte.
53 */
54 #define PL_S_EN (1<<7) /* (feature only) suspend enable */
55 /* reserved bit -- rx ready (6) ? */
56 #define PL_TX_READY (1<<5) /* (interrupt only) transmit ready */
57 #define PL_RESET_OUT (1<<4) /* reset output pipe */
58 #define PL_RESET_IN (1<<3) /* reset input pipe */
59 #define PL_TX_C (1<<2) /* transmission complete */
60 #define PL_TX_REQ (1<<1) /* transmission received */
61 #define PL_PEER_E (1<<0) /* peer exists */
62
63 static inline int
pl_vendor_req(struct usbnet * dev,u8 req,u8 val,u8 index)64 pl_vendor_req(struct usbnet *dev, u8 req, u8 val, u8 index)
65 {
66 return usb_control_msg(dev->udev,
67 usb_rcvctrlpipe(dev->udev, 0),
68 req,
69 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
70 val, index,
71 NULL, 0,
72 USB_CTRL_GET_TIMEOUT);
73 }
74
75 static inline int
pl_clear_QuickLink_features(struct usbnet * dev,int val)76 pl_clear_QuickLink_features(struct usbnet *dev, int val)
77 {
78 return pl_vendor_req(dev, 1, (u8) val, 0);
79 }
80
81 static inline int
pl_set_QuickLink_features(struct usbnet * dev,int val)82 pl_set_QuickLink_features(struct usbnet *dev, int val)
83 {
84 return pl_vendor_req(dev, 3, (u8) val, 0);
85 }
86
pl_reset(struct usbnet * dev)87 static int pl_reset(struct usbnet *dev)
88 {
89 /* some units seem to need this reset, others reject it utterly.
90 * FIXME be more like "naplink" or windows drivers.
91 */
92 (void) pl_set_QuickLink_features(dev,
93 PL_S_EN|PL_RESET_OUT|PL_RESET_IN|PL_PEER_E);
94 return 0;
95 }
96
97 static const struct driver_info prolific_info = {
98 .description = "Prolific PL-2301/PL-2302",
99 .flags = FLAG_NO_SETINT,
100 /* some PL-2302 versions seem to fail usb_set_interface() */
101 .reset = pl_reset,
102 };
103
104
105 /*-------------------------------------------------------------------------*/
106
107 /*
108 * Proilific's name won't normally be on the cables, and
109 * may not be on the device.
110 */
111
112 static const struct usb_device_id products [] = {
113
114 {
115 USB_DEVICE(0x067b, 0x0000), // PL-2301
116 .driver_info = (unsigned long) &prolific_info,
117 }, {
118 USB_DEVICE(0x067b, 0x0001), // PL-2302
119 .driver_info = (unsigned long) &prolific_info,
120 },
121
122 { }, // END
123 };
124 MODULE_DEVICE_TABLE(usb, products);
125
126 static struct usb_driver plusb_driver = {
127 .name = "plusb",
128 .id_table = products,
129 .probe = usbnet_probe,
130 .disconnect = usbnet_disconnect,
131 .suspend = usbnet_suspend,
132 .resume = usbnet_resume,
133 };
134
plusb_init(void)135 static int __init plusb_init(void)
136 {
137 return usb_register(&plusb_driver);
138 }
139 module_init(plusb_init);
140
plusb_exit(void)141 static void __exit plusb_exit(void)
142 {
143 usb_deregister(&plusb_driver);
144 }
145 module_exit(plusb_exit);
146
147 MODULE_AUTHOR("David Brownell");
148 MODULE_DESCRIPTION("Prolific PL-2301/2302 USB Host to Host Link Driver");
149 MODULE_LICENSE("GPL");
150