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 #include <linux/gfp.h> 34 35 36 /* 37 * GeneSys GL620USB-A (www.genesyslogic.com.tw) 38 * 39 * ... should partially interop with the Win32 driver for this hardware. 40 * The GeneSys docs imply there's some NDIS issue motivating this framing. 41 * 42 * Some info from GeneSys: 43 * - GL620USB-A is full duplex; GL620USB is only half duplex for bulk. 44 * (Some cables, like the BAFO-100c, use the half duplex version.) 45 * - For the full duplex model, the low bit of the version code says 46 * which side is which ("left/right"). 47 * - For the half duplex type, a control/interrupt handshake settles 48 * the transfer direction. (That's disabled here, partially coded.) 49 * A control URB would block until other side writes an interrupt. 50 * 51 * Original code from Jiun-Jie Huang <huangjj@genesyslogic.com.tw> 52 * and merged into "usbnet" by Stanislav Brabec <utx@penguin.cz>. 53 */ 54 55 // control msg write command 56 #define GENELINK_CONNECT_WRITE 0xF0 57 // interrupt pipe index 58 #define GENELINK_INTERRUPT_PIPE 0x03 59 // interrupt read buffer size 60 #define INTERRUPT_BUFSIZE 0x08 61 // interrupt pipe interval value 62 #define GENELINK_INTERRUPT_INTERVAL 0x10 63 // max transmit packet number per transmit 64 #define GL_MAX_TRANSMIT_PACKETS 32 65 // max packet length 66 #define GL_MAX_PACKET_LEN 1514 67 // max receive buffer size 68 #define GL_RCV_BUF_SIZE \ 69 (((GL_MAX_PACKET_LEN + 4) * GL_MAX_TRANSMIT_PACKETS) + 4) 70 71 struct gl_packet { 72 __le32 packet_length; 73 char packet_data [1]; 74 }; 75 76 struct gl_header { 77 __le32 packet_count; 78 struct gl_packet packets; 79 }; 80 81 static int genelink_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 82 { 83 struct gl_header *header; 84 struct gl_packet *packet; 85 struct sk_buff *gl_skb; 86 u32 size; 87 u32 count; 88 89 header = (struct gl_header *) skb->data; 90 91 // get the packet count of the received skb 92 count = le32_to_cpu(header->packet_count); 93 if (count > GL_MAX_TRANSMIT_PACKETS) { 94 dbg("genelink: invalid received packet count %u", count); 95 return 0; 96 } 97 98 // set the current packet pointer to the first packet 99 packet = &header->packets; 100 101 // decrement the length for the packet count size 4 bytes 102 skb_pull(skb, 4); 103 104 while (count > 1) { 105 // get the packet length 106 size = le32_to_cpu(packet->packet_length); 107 108 // this may be a broken packet 109 if (size > GL_MAX_PACKET_LEN) { 110 dbg("genelink: invalid rx length %d", size); 111 return 0; 112 } 113 114 // allocate the skb for the individual packet 115 gl_skb = alloc_skb(size, GFP_ATOMIC); 116 if (gl_skb) { 117 118 // copy the packet data to the new skb 119 memcpy(skb_put(gl_skb, size), 120 packet->packet_data, size); 121 usbnet_skb_return(dev, gl_skb); 122 } 123 124 // advance to the next packet 125 packet = (struct gl_packet *)&packet->packet_data[size]; 126 count--; 127 128 // shift the data pointer to the next gl_packet 129 skb_pull(skb, size + 4); 130 } 131 132 // skip the packet length field 4 bytes 133 skb_pull(skb, 4); 134 135 if (skb->len > GL_MAX_PACKET_LEN) { 136 dbg("genelink: invalid rx length %d", skb->len); 137 return 0; 138 } 139 return 1; 140 } 141 142 static struct sk_buff * 143 genelink_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) 144 { 145 int padlen; 146 int length = skb->len; 147 int headroom = skb_headroom(skb); 148 int tailroom = skb_tailroom(skb); 149 __le32 *packet_count; 150 __le32 *packet_len; 151 152 // FIXME: magic numbers, bleech 153 padlen = ((skb->len + (4 + 4*1)) % 64) ? 0 : 1; 154 155 if ((!skb_cloned(skb)) 156 && ((headroom + tailroom) >= (padlen + (4 + 4*1)))) { 157 if ((headroom < (4 + 4*1)) || (tailroom < padlen)) { 158 skb->data = memmove(skb->head + (4 + 4*1), 159 skb->data, skb->len); 160 skb_set_tail_pointer(skb, skb->len); 161 } 162 } else { 163 struct sk_buff *skb2; 164 skb2 = skb_copy_expand(skb, (4 + 4*1) , padlen, flags); 165 dev_kfree_skb_any(skb); 166 skb = skb2; 167 if (!skb) 168 return NULL; 169 } 170 171 // attach the packet count to the header 172 packet_count = (__le32 *) skb_push(skb, (4 + 4*1)); 173 packet_len = packet_count + 1; 174 175 *packet_count = cpu_to_le32(1); 176 *packet_len = cpu_to_le32(length); 177 178 // add padding byte 179 if ((skb->len % dev->maxpacket) == 0) 180 skb_put(skb, 1); 181 182 return skb; 183 } 184 185 static int genelink_bind(struct usbnet *dev, struct usb_interface *intf) 186 { 187 dev->hard_mtu = GL_RCV_BUF_SIZE; 188 dev->net->hard_header_len += 4; 189 dev->in = usb_rcvbulkpipe(dev->udev, dev->driver_info->in); 190 dev->out = usb_sndbulkpipe(dev->udev, dev->driver_info->out); 191 return 0; 192 } 193 194 static const struct driver_info genelink_info = { 195 .description = "Genesys GeneLink", 196 .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_GL | FLAG_NO_SETINT, 197 .bind = genelink_bind, 198 .rx_fixup = genelink_rx_fixup, 199 .tx_fixup = genelink_tx_fixup, 200 201 .in = 1, .out = 2, 202 203 #ifdef GENELINK_ACK 204 .check_connect =genelink_check_connect, 205 #endif 206 }; 207 208 static const struct usb_device_id products [] = { 209 210 { 211 USB_DEVICE(0x05e3, 0x0502), // GL620USB-A 212 .driver_info = (unsigned long) &genelink_info, 213 }, 214 /* NOT: USB_DEVICE(0x05e3, 0x0501), // GL620USB 215 * that's half duplex, not currently supported 216 */ 217 { }, // END 218 }; 219 MODULE_DEVICE_TABLE(usb, products); 220 221 static struct usb_driver gl620a_driver = { 222 .name = "gl620a", 223 .id_table = products, 224 .probe = usbnet_probe, 225 .disconnect = usbnet_disconnect, 226 .suspend = usbnet_suspend, 227 .resume = usbnet_resume, 228 }; 229 230 module_usb_driver(gl620a_driver); 231 232 MODULE_AUTHOR("Jiun-Jie Huang"); 233 MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables"); 234 MODULE_LICENSE("GPL"); 235 236