summaryrefslogtreecommitdiffstats
path: root/drivers/net/usb/gl620a.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/usb/gl620a.c')
-rw-r--r--drivers/net/usb/gl620a.c229
1 files changed, 229 insertions, 0 deletions
diff --git a/drivers/net/usb/gl620a.c b/drivers/net/usb/gl620a.c
new file mode 100644
index 000000000..46af78caf
--- /dev/null
+++ b/drivers/net/usb/gl620a.c
@@ -0,0 +1,229 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+
+// #define DEBUG // error path messages, extra info
+// #define VERBOSE // more; success messages
+
+#include <linux/module.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 <linux/usb/usbnet.h>
+#include <linux/gfp.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 {
+ __le32 packet_length;
+ char packet_data[];
+};
+
+struct gl_header {
+ __le32 packet_count;
+ struct gl_packet packets;
+};
+
+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;
+ u32 count;
+
+ /* This check is no longer done by usbnet */
+ if (skb->len < dev->net->hard_header_len)
+ return 0;
+
+ header = (struct gl_header *) skb->data;
+
+ // get the packet count of the received skb
+ count = le32_to_cpu(header->packet_count);
+ if (count > GL_MAX_TRANSMIT_PACKETS) {
+ netdev_dbg(dev->net,
+ "genelink: invalid received packet count %u\n",
+ 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 (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) {
+ netdev_dbg(dev->net, "genelink: invalid rx length %d\n",
+ 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
+ skb_put_data(gl_skb, packet->packet_data, size);
+ usbnet_skb_return(dev, gl_skb);
+ }
+
+ // advance to the next packet
+ packet = (struct gl_packet *)&packet->packet_data[size];
+ 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) {
+ netdev_dbg(dev->net, "genelink: invalid rx length %d\n",
+ 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);
+ __le32 *packet_count;
+ __le32 *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_set_tail_pointer(skb, 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 = 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_POINTTOPOINT | 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,
+ .disable_hub_initiated_lpm = 1,
+};
+
+module_usb_driver(gl620a_driver);
+
+MODULE_AUTHOR("Jiun-Jie Huang");
+MODULE_DESCRIPTION("GL620-USB-A Host-to-Host Link cables");
+MODULE_LICENSE("GPL");
+