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 32 #include "usbnet.h" 33 34 35 /* 36 * Prolific PL-2301/PL-2302 driver ... http://www.prolifictech.com 37 * 38 * The protocol and handshaking used here should be bug-compatible 39 * with the Linux 2.2 "plusb" driver, by Deti Fliegl. 40 * 41 * HEADS UP: this handshaking isn't all that robust. This driver 42 * gets confused easily if you unplug one end of the cable then 43 * try to connect it again; you'll need to restart both ends. The 44 * "naplink" software (used by some PlayStation/2 deveopers) does 45 * the handshaking much better! Also, sometimes this hardware 46 * seems to get wedged under load. Prolific docs are weak, and 47 * don't identify differences between PL2301 and PL2302, much less 48 * anything to explain the different PL2302 versions observed. 49 */ 50 51 /* 52 * Bits 0-4 can be used for software handshaking; they're set from 53 * one end, cleared from the other, "read" with the interrupt byte. 54 */ 55 #define PL_S_EN (1<<7) /* (feature only) suspend enable */ 56 /* reserved bit -- rx ready (6) ? */ 57 #define PL_TX_READY (1<<5) /* (interrupt only) transmit ready */ 58 #define PL_RESET_OUT (1<<4) /* reset output pipe */ 59 #define PL_RESET_IN (1<<3) /* reset input pipe */ 60 #define PL_TX_C (1<<2) /* transmission complete */ 61 #define PL_TX_REQ (1<<1) /* transmission received */ 62 #define PL_PEER_E (1<<0) /* peer exists */ 63 64 static inline int 65 pl_vendor_req(struct usbnet *dev, u8 req, u8 val, u8 index) 66 { 67 return usb_control_msg(dev->udev, 68 usb_rcvctrlpipe(dev->udev, 0), 69 req, 70 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 71 val, index, 72 NULL, 0, 73 USB_CTRL_GET_TIMEOUT); 74 } 75 76 static inline int 77 pl_clear_QuickLink_features(struct usbnet *dev, int val) 78 { 79 return pl_vendor_req(dev, 1, (u8) val, 0); 80 } 81 82 static inline int 83 pl_set_QuickLink_features(struct usbnet *dev, int val) 84 { 85 return pl_vendor_req(dev, 3, (u8) val, 0); 86 } 87 88 static int pl_reset(struct usbnet *dev) 89 { 90 /* some units seem to need this reset, others reject it utterly. 91 * FIXME be more like "naplink" or windows drivers. 92 */ 93 (void) pl_set_QuickLink_features(dev, 94 PL_S_EN|PL_RESET_OUT|PL_RESET_IN|PL_PEER_E); 95 return 0; 96 } 97 98 static const struct driver_info prolific_info = { 99 .description = "Prolific PL-2301/PL-2302", 100 .flags = FLAG_NO_SETINT, 101 /* some PL-2302 versions seem to fail usb_set_interface() */ 102 .reset = pl_reset, 103 }; 104 105 106 /*-------------------------------------------------------------------------*/ 107 108 /* 109 * Proilific's name won't normally be on the cables, and 110 * may not be on the device. 111 */ 112 113 static const struct usb_device_id products [] = { 114 115 { 116 USB_DEVICE(0x067b, 0x0000), // PL-2301 117 .driver_info = (unsigned long) &prolific_info, 118 }, { 119 USB_DEVICE(0x067b, 0x0001), // PL-2302 120 .driver_info = (unsigned long) &prolific_info, 121 }, 122 123 { }, // END 124 }; 125 MODULE_DEVICE_TABLE(usb, products); 126 127 static struct usb_driver plusb_driver = { 128 .name = "plusb", 129 .id_table = products, 130 .probe = usbnet_probe, 131 .disconnect = usbnet_disconnect, 132 .suspend = usbnet_suspend, 133 .resume = usbnet_resume, 134 }; 135 136 static int __init plusb_init(void) 137 { 138 return usb_register(&plusb_driver); 139 } 140 module_init(plusb_init); 141 142 static void __exit plusb_exit(void) 143 { 144 usb_deregister(&plusb_driver); 145 } 146 module_exit(plusb_exit); 147 148 MODULE_AUTHOR("David Brownell"); 149 MODULE_DESCRIPTION("Prolific PL-2301/2302 USB Host to Host Link Driver"); 150 MODULE_LICENSE("GPL"); 151