1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * GeneSys GL620USB-A based links
4  * Copyright (C) 2001 by Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
23  * GeneSys GL620USB-A (www.genesyslogic.com.tw)
29  *  - GL620USB-A is full duplex; GL620USB is only half duplex for bulk.
30  *    (Some cables, like the BAFO-100c, use the half duplex version.)
31  *  - For the full duplex model, the low bit of the version code says
33  *  - For the half duplex type, a control/interrupt handshake settles
37  * Original code from Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
49 // max transmit packet number per transmit
51 // max packet length
70 	struct gl_packet	*packet;  in genelink_rx_fixup()  local
76 	if (skb->len < dev->net->hard_header_len)  in genelink_rx_fixup()
79 	header = (struct gl_header *) skb->data;  in genelink_rx_fixup()
81 	// get the packet count of the received skb  in genelink_rx_fixup()
82 	count = le32_to_cpu(header->packet_count);  in genelink_rx_fixup()
84 		netdev_dbg(dev->net,  in genelink_rx_fixup()
85 			   "genelink: invalid received packet count %u\n",  in genelink_rx_fixup()
90 	// set the current packet pointer to the first packet  in genelink_rx_fixup()
91 	packet = &header->packets;  in genelink_rx_fixup()
93 	// decrement the length for the packet count size 4 bytes  in genelink_rx_fixup()
97 		// get the packet length  in genelink_rx_fixup()
98 		size = le32_to_cpu(packet->packet_length);  in genelink_rx_fixup()
100 		// this may be a broken packet  in genelink_rx_fixup()
102 			netdev_dbg(dev->net, "genelink: invalid rx length %d\n",  in genelink_rx_fixup()
107 		// allocate the skb for the individual packet  in genelink_rx_fixup()
111 			// copy the packet data to the new skb  in genelink_rx_fixup()
112 			skb_put_data(gl_skb, packet->packet_data, size);  in genelink_rx_fixup()
116 		// advance to the next packet  in genelink_rx_fixup()
117 		packet = (struct gl_packet *)&packet->packet_data[size];  in genelink_rx_fixup()
118 		count--;  in genelink_rx_fixup()
124 	// skip the packet length field 4 bytes  in genelink_rx_fixup()
127 	if (skb->len > GL_MAX_PACKET_LEN) {  in genelink_rx_fixup()
128 		netdev_dbg(dev->net, "genelink: invalid rx length %d\n",  in genelink_rx_fixup()
129 			   skb->len);  in genelink_rx_fixup()
139 	int	length = skb->len;  in genelink_tx_fixup()
145 	// FIXME:  magic numbers, bleech  in genelink_tx_fixup()
146 	padlen = ((skb->len + (4 + 4*1)) % 64) ? 0 : 1;  in genelink_tx_fixup()
151 			skb->data = memmove(skb->head + (4 + 4*1),  in genelink_tx_fixup()
152 					     skb->data, skb->len);  in genelink_tx_fixup()
153 			skb_set_tail_pointer(skb, skb->len);  in genelink_tx_fixup()
164 	// attach the packet count to the header  in genelink_tx_fixup()
172 	if ((skb->len % dev->maxpacket) == 0)  in genelink_tx_fixup()
180 	dev->hard_mtu = GL_RCV_BUF_SIZE;  in genelink_bind()
181 	dev->net->hard_header_len += 4;  in genelink_bind()
182 	dev->in = usb_rcvbulkpipe(dev->udev, dev->driver_info->in);  in genelink_bind()
183 	dev->out = usb_sndbulkpipe(dev->udev, dev->driver_info->out);  in genelink_bind()
204 	USB_DEVICE(0x05e3, 0x0502),	// GL620USB-A
226 MODULE_AUTHOR("Jiun-Jie Huang");
227 MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables");