[PATCH] USB: usbnet (5/9) module for genesys gl620a cables
This moves the GeneSys GL620USB-A support into its own driver file.
It also fixes a "return wrong skb" glitch in the rx unbatching, as
recently reported, and adds some missing byteswaps in the special
"genelink" headers (so it might now work on big-endian Linux).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/net/gl620a.c b/drivers/usb/net/gl620a.c
new file mode 100644
index 0000000..c8763ae
--- /dev/null
+++ b/drivers/usb/net/gl620a.c
@@ -0,0 +1,407 @@
+/*
+ * 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>
+#ifdef CONFIG_USB_DEBUG
+# define DEBUG
+#endif
+#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, unsigned 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 = {
+ .owner = THIS_MODULE,
+ .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");
+