/*
* GeneSys GL620USB-A based links
* Copyright (C) 2001 by Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
* Copyright (C) 2001 by Stanislav Brabec <utx@penguin.cz>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
// #define DEBUG // error path messages, extra info
// #define VERBOSE // more; success messages
#include <linux/config.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/workqueue.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include "usbnet.h"
/*
* GeneSys GL620USB-A (www.genesyslogic.com.tw)
*
* ... should partially interop with the Win32 driver for this hardware.
* The GeneSys docs imply there's some NDIS issue motivating this framing.
*
* Some info from GeneSys:
* - GL620USB-A is full duplex; GL620USB is only half duplex for bulk.
* (Some cables, like the BAFO-100c, use the half duplex version.)
* - For the full duplex model, the low bit of the version code says
* which side is which ("left/right").
* - For the half duplex type, a control/interrupt handshake settles
* the transfer direction. (That's disabled here, partially coded.)
* A control URB would block until other side writes an interrupt.
*
* Original code from Jiun-Jie Huang <huangjj@genesyslogic.com.tw>
* and merged into "usbnet" by Stanislav Brabec <utx@penguin.cz>.
*/
// control msg write command
#define GENELINK_CONNECT_WRITE 0xF0
// interrupt pipe index
#define GENELINK_INTERRUPT_PIPE 0x03
// interrupt read buffer size
#define INTERRUPT_BUFSIZE 0x08
// interrupt pipe interval value
#define GENELINK_INTERRUPT_INTERVAL 0x10
// max transmit packet number per transmit
#define GL_MAX_TRANSMIT_PACKETS 32
// max packet length
#define GL_MAX_PACKET_LEN 1514
// max receive buffer size
#define GL_RCV_BUF_SIZE \
(((GL_MAX_PACKET_LEN + 4) * GL_MAX_TRANSMIT_PACKETS) + 4)
struct gl_packet {
u32 packet_length;
char packet_data [1];
};
struct gl_header {
u32 packet_count;
struct gl_packet packets;
};
#ifdef GENELINK_ACK
// FIXME: this code is incomplete, not debugged; it doesn't
// handle interrupts correctly; it should use the generic
// status IRQ code (which didn't exist back in 2001).
struct gl_priv {
struct urb *irq_urb;
char irq_buf [INTERRUPT_BUFSIZE];
};
static inline int gl_control_write(struct usbnet *dev, u8 request, u16 value)
{
int retval;
retval = usb_control_msg(dev->udev,
usb_sndctrlpipe(dev->udev, 0),
request,
USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
value,
0, // index
0, // data buffer
0, // size
USB_CTRL_SET_TIMEOUT);
return retval;
}
static void gl_interrupt_complete(struct urb *urb, struct pt_regs *regs)
{
int status = urb->status;
switch (status) {
case 0:
/* success */
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d",
__FUNCTION__, status);
return;
default:
dbg("%s - nonzero urb status received: %d",
__FUNCTION__, urb->status);
}
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status)
err("%s - usb_submit_urb failed with result %d",
__FUNCTION__, status);
}
static int gl_interrupt_read(struct usbnet *dev)
{
struct gl_priv *priv = dev->priv_data;
int retval;
// issue usb interrupt read
if (priv && priv->irq_urb) {
// submit urb
if ((retval = usb_submit_urb(priv->irq_urb, GFP_KERNEL)) != 0)
dbg("gl_interrupt_read: submit fail - %X...", retval);
else
dbg("gl_interrupt_read: submit success...");
}
return 0;
}
// check whether another side is connected
static int genelink_check_connect(struct usbnet *dev)
{
int retval;
dbg("genelink_check_connect...");
// detect whether another side is connected
if ((retval = gl_control_write(dev, GENELINK_CONNECT_WRITE, 0)) != 0) {
dbg("%s: genelink_check_connect write fail - %X",
dev->net->name, retval);
return retval;
}
// usb interrupt read to ack another side
if ((retval = gl_interrupt_read(dev)) != 0) {
dbg("%s: genelink_check_connect read fail - %X",
dev->net->name, retval);
return retval;
}
dbg("%s: genelink_check_connect read success", dev->net->name);
return 0;
}
// allocate and initialize the private data for genelink
static int genelink_init(struct usbnet *dev)
{
struct gl_priv *priv;
// allocate the private data structure
if ((priv = kmalloc(sizeof *priv, GFP_KERNEL)) == 0) {
dbg("%s: cannot allocate private data per device",
dev->net->name);
return -ENOMEM;
}
// allocate irq urb
if ((priv->irq_urb = usb_alloc_urb(0, GFP_KERNEL)) == 0) {
dbg("%s: cannot allocate private irq urb per device",
dev->net->name);
kfree(priv);
return -ENOMEM;
}
// fill irq urb
usb_fill_int_urb(priv->irq_urb, dev->udev,
usb_rcvintpipe(dev->udev, GENELINK_INTERRUPT_PIPE),
priv->irq_buf, INTERRUPT_BUFSIZE,
gl_interrupt_complete, 0,
GENELINK_INTERRUPT_INTERVAL);
// set private data pointer
dev->priv_data = priv;
return 0;
}
// release the private data
static int genelink_free(struct usbnet *dev)
{
struct gl_priv *priv = dev->priv_data;
if (!priv)
return 0;
// FIXME: can't cancel here; it's synchronous, and
// should have happened earlier in any case (interrupt
// handling needs to be generic)
// cancel irq urb first
usb_kill_urb(priv->irq_urb);
// free irq urb
usb_free_urb(priv->irq_urb);
// free the private data structure
kfree(priv);
return 0;
}
#endif
static int genelink_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
{
struct gl_header *header;
struct gl_packet *packet;
struct sk_buff *gl_skb;
u32 size;
header = (struct gl_header *) skb->data;
// get the packet count of the received skb
le32_to_cpus(&header->packet_count);
if ((header->packet_count > GL_MAX_TRANSMIT_PACKETS)
|| (header->packet_count < 0)) {
dbg("genelink: invalid received packet count %d",
header->packet_count);
return 0;
}
// set the current packet pointer to the first packet
packet = &header->packets;
// decrement the length for the packet count size 4 bytes
skb_pull(skb, 4);
while (header->packet_count > 1) {
// get the packet length
size = le32_to_cpu(packet->packet_length);
// this may be a broken packet
if (size > GL_MAX_PACKET_LEN) {
dbg("genelink: invalid rx length %d", size);
return 0;
}
// allocate the skb for the individual packet
gl_skb = alloc_skb(size, GFP_ATOMIC);
if (gl_skb) {
// copy the packet data to the new skb
memcpy(skb_put(gl_skb, size),
packet->packet_data, size);
usbnet_skb_return(dev, gl_skb);
}
// advance to the next packet
packet = (struct gl_packet *)
&packet->packet_data [size];
header->packet_count--;
// shift the data pointer to the next gl_packet
skb_pull(skb, size + 4);
}
// skip the packet length field 4 bytes
skb_pull(skb, 4);
if (skb->len > GL_MAX_PACKET_LEN) {
dbg("genelink: invalid rx length %d", skb->len);
return 0;
}
return 1;
}
static struct sk_buff *
genelink_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
{
int padlen;
int length = skb->len;
int headroom = skb_headroom(skb);
int tailroom = skb_tailroom(skb);
u32 *packet_count;
u32 *packet_len;
// FIXME: magic numbers, bleech
padlen = ((skb->len + (4 + 4*1)) % 64) ? 0 : 1;
if ((!skb_cloned(skb))
&& ((headroom + tailroom) >= (padlen + (4 + 4*1)))) {
if ((headroom < (4 + 4*1)) || (tailroom < padlen)) {
skb->data = memmove(skb->head + (4 + 4*1),
skb->data, skb->len);
skb->tail = skb->data + skb->len;
}
} else {
struct sk_buff *skb2;
skb2 = skb_copy_expand(skb, (4 + 4*1) , padlen, flags);
dev_kfree_skb_any(skb);
skb = skb2;
if (!skb)
return NULL;
}
// attach the packet count to the header
packet_count = (u32 *) skb_push(skb, (4 + 4*1));
packet_len = packet_count + 1;
*packet_count = cpu_to_le32(1);
*packet_len = cpu_to_le32(length);
// add padding byte
if ((skb->len % dev->maxpacket) == 0)
skb_put(skb, 1);
return skb;
}
static int genelink_bind(struct usbnet *dev, struct usb_interface *intf)
{
dev->hard_mtu = GL_RCV_BUF_SIZE;
dev->net->hard_header_len += 4;
dev->in = usb_rcvbulkpipe(dev->udev, dev->driver_info->in);
dev->out = usb_sndbulkpipe(dev->udev, dev->driver_info->out);
return 0;
}
static const struct driver_info genelink_info = {
.description = "Genesys GeneLink",
.flags = FLAG_FRAMING_GL | FLAG_NO_SETINT,
.bind = genelink_bind,
.rx_fixup = genelink_rx_fixup,
.tx_fixup = genelink_tx_fixup,
.in = 1, .out = 2,
#ifdef GENELINK_ACK
.check_connect =genelink_check_connect,
#endif
};
static const struct usb_device_id products [] = {
{
USB_DEVICE(0x05e3, 0x0502), // GL620USB-A
.driver_info = (unsigned long) &genelink_info,
},
/* NOT: USB_DEVICE(0x05e3, 0x0501), // GL620USB
* that's half duplex, not currently supported
*/
{ }, // END
};
MODULE_DEVICE_TABLE(usb, products);
static struct usb_driver gl620a_driver = {
.name = "gl620a",
.id_table = products,
.probe = usbnet_probe,
.disconnect = usbnet_disconnect,
.suspend = usbnet_suspend,
.resume = usbnet_resume,
};
static int __init usbnet_init(void)
{
return usb_register(&gl620a_driver);
}
module_init(usbnet_init);
static void __exit usbnet_exit(void)
{
usb_deregister(&gl620a_driver);
}
module_exit(usbnet_exit);
MODULE_AUTHOR("Jiun-Jie Huang");
MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables");
MODULE_LICENSE("GPL");
