1 /* 2 * GeneSys GL620USB-A based links 3 * Copyright (C) 2001 by Jiun-Jie Huang <huangjj@genesyslogic.com.tw> 4 * Copyright (C) 2001 by Stanislav Brabec <utx@penguin.cz> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 */ 20 21 // #define DEBUG // error path messages, extra info 22 // #define VERBOSE // more; success messages 23 24 #include <linux/module.h> 25 #include <linux/init.h> 26 #include <linux/netdevice.h> 27 #include <linux/etherdevice.h> 28 #include <linux/ethtool.h> 29 #include <linux/workqueue.h> 30 #include <linux/mii.h> 31 #include <linux/usb.h> 32 #include <linux/usb/usbnet.h> 33 34 35 /* 36 * GeneSys GL620USB-A (www.genesyslogic.com.tw) 37 * 38 * ... should partially interop with the Win32 driver for this hardware. 39 * The GeneSys docs imply there's some NDIS issue motivating this framing. 40 * 41 * Some info from GeneSys: 42 * - GL620USB-A is full duplex; GL620USB is only half duplex for bulk. 43 * (Some cables, like the BAFO-100c, use the half duplex version.) 44 * - For the full duplex model, the low bit of the version code says 45 * which side is which ("left/right"). 46 * - For the half duplex type, a control/interrupt handshake settles 47 * the transfer direction. (That's disabled here, partially coded.) 48 * A control URB would block until other side writes an interrupt. 49 * 50 * Original code from Jiun-Jie Huang <huangjj@genesyslogic.com.tw> 51 * and merged into "usbnet" by Stanislav Brabec <utx@penguin.cz>. 52 */ 53 54 // control msg write command 55 #define GENELINK_CONNECT_WRITE 0xF0 56 // interrupt pipe index 57 #define GENELINK_INTERRUPT_PIPE 0x03 58 // interrupt read buffer size 59 #define INTERRUPT_BUFSIZE 0x08 60 // interrupt pipe interval value 61 #define GENELINK_INTERRUPT_INTERVAL 0x10 62 // max transmit packet number per transmit 63 #define GL_MAX_TRANSMIT_PACKETS 32 64 // max packet length 65 #define GL_MAX_PACKET_LEN 1514 66 // max receive buffer size 67 #define GL_RCV_BUF_SIZE \ 68 (((GL_MAX_PACKET_LEN + 4) * GL_MAX_TRANSMIT_PACKETS) + 4) 69 70 struct gl_packet { 71 __le32 packet_length; 72 char packet_data [1]; 73 }; 74 75 struct gl_header { 76 __le32 packet_count; 77 struct gl_packet packets; 78 }; 79 80 static int genelink_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 81 { 82 struct gl_header *header; 83 struct gl_packet *packet; 84 struct sk_buff *gl_skb; 85 u32 size; 86 u32 count; 87 88 header = (struct gl_header *) skb->data; 89 90 // get the packet count of the received skb 91 count = le32_to_cpu(header->packet_count); 92 if (count > GL_MAX_TRANSMIT_PACKETS) { 93 dbg("genelink: invalid received packet count %u", count); 94 return 0; 95 } 96 97 // set the current packet pointer to the first packet 98 packet = &header->packets; 99 100 // decrement the length for the packet count size 4 bytes 101 skb_pull(skb, 4); 102 103 while (count > 1) { 104 // get the packet length 105 size = le32_to_cpu(packet->packet_length); 106 107 // this may be a broken packet 108 if (size > GL_MAX_PACKET_LEN) { 109 dbg("genelink: invalid rx length %d", size); 110 return 0; 111 } 112 113 // allocate the skb for the individual packet 114 gl_skb = alloc_skb(size, GFP_ATOMIC); 115 if (gl_skb) { 116 117 // copy the packet data to the new skb 118 memcpy(skb_put(gl_skb, size), 119 packet->packet_data, size); 120 usbnet_skb_return(dev, gl_skb); 121 } 122 123 // advance to the next packet 124 packet = (struct gl_packet *)&packet->packet_data[size]; 125 count--; 126 127 // shift the data pointer to the next gl_packet 128 skb_pull(skb, size + 4); 129 } 130 131 // skip the packet length field 4 bytes 132 skb_pull(skb, 4); 133 134 if (skb->len > GL_MAX_PACKET_LEN) { 135 dbg("genelink: invalid rx length %d", skb->len); 136 return 0; 137 } 138 return 1; 139 } 140 141 static struct sk_buff * 142 genelink_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) 143 { 144 int padlen; 145 int length = skb->len; 146 int headroom = skb_headroom(skb); 147 int tailroom = skb_tailroom(skb); 148 __le32 *packet_count; 149 __le32 *packet_len; 150 151 // FIXME: magic numbers, bleech 152 padlen = ((skb->len + (4 + 4*1)) % 64) ? 0 : 1; 153 154 if ((!skb_cloned(skb)) 155 && ((headroom + tailroom) >= (padlen + (4 + 4*1)))) { 156 if ((headroom < (4 + 4*1)) || (tailroom < padlen)) { 157 skb->data = memmove(skb->head + (4 + 4*1), 158 skb->data, skb->len); 159 skb_set_tail_pointer(skb, skb->len); 160 } 161 } else { 162 struct sk_buff *skb2; 163 skb2 = skb_copy_expand(skb, (4 + 4*1) , padlen, flags); 164 dev_kfree_skb_any(skb); 165 skb = skb2; 166 if (!skb) 167 return NULL; 168 } 169 170 // attach the packet count to the header 171 packet_count = (__le32 *) skb_push(skb, (4 + 4*1)); 172 packet_len = packet_count + 1; 173 174 *packet_count = cpu_to_le32(1); 175 *packet_len = cpu_to_le32(length); 176 177 // add padding byte 178 if ((skb->len % dev->maxpacket) == 0) 179 skb_put(skb, 1); 180 181 return skb; 182 } 183 184 static int genelink_bind(struct usbnet *dev, struct usb_interface *intf) 185 { 186 dev->hard_mtu = GL_RCV_BUF_SIZE; 187 dev->net->hard_header_len += 4; 188 dev->in = usb_rcvbulkpipe(dev->udev, dev->driver_info->in); 189 dev->out = usb_sndbulkpipe(dev->udev, dev->driver_info->out); 190 return 0; 191 } 192 193 static const struct driver_info genelink_info = { 194 .description = "Genesys GeneLink", 195 .flags = FLAG_FRAMING_GL | FLAG_NO_SETINT, 196 .bind = genelink_bind, 197 .rx_fixup = genelink_rx_fixup, 198 .tx_fixup = genelink_tx_fixup, 199 200 .in = 1, .out = 2, 201 202 #ifdef GENELINK_ACK 203 .check_connect =genelink_check_connect, 204 #endif 205 }; 206 207 static const struct usb_device_id products [] = { 208 209 { 210 USB_DEVICE(0x05e3, 0x0502), // GL620USB-A 211 .driver_info = (unsigned long) &genelink_info, 212 }, 213 /* NOT: USB_DEVICE(0x05e3, 0x0501), // GL620USB 214 * that's half duplex, not currently supported 215 */ 216 { }, // END 217 }; 218 MODULE_DEVICE_TABLE(usb, products); 219 220 static struct usb_driver gl620a_driver = { 221 .name = "gl620a", 222 .id_table = products, 223 .probe = usbnet_probe, 224 .disconnect = usbnet_disconnect, 225 .suspend = usbnet_suspend, 226 .resume = usbnet_resume, 227 }; 228 229 static int __init usbnet_init(void) 230 { 231 return usb_register(&gl620a_driver); 232 } 233 module_init(usbnet_init); 234 235 static void __exit usbnet_exit(void) 236 { 237 usb_deregister(&gl620a_driver); 238 } 239 module_exit(usbnet_exit); 240 241 MODULE_AUTHOR("Jiun-Jie Huang"); 242 MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables"); 243 MODULE_LICENSE("GPL"); 244 245