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Diffstat (limited to 'drivers/net/usb/cx82310_eth.c')
-rw-r--r--drivers/net/usb/cx82310_eth.c375
1 files changed, 375 insertions, 0 deletions
diff --git a/drivers/net/usb/cx82310_eth.c b/drivers/net/usb/cx82310_eth.c
new file mode 100644
index 000000000..79a47e2fd
--- /dev/null
+++ b/drivers/net/usb/cx82310_eth.c
@@ -0,0 +1,375 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for USB ethernet port of Conexant CX82310-based ADSL routers
+ * Copyright (C) 2010 by Ondrej Zary
+ * some parts inspired by the cxacru driver
+ */
+
+#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>
+
+enum cx82310_cmd {
+ CMD_START = 0x84, /* no effect? */
+ CMD_STOP = 0x85, /* no effect? */
+ CMD_GET_STATUS = 0x90, /* returns nothing? */
+ CMD_GET_MAC_ADDR = 0x91, /* read MAC address */
+ CMD_GET_LINK_STATUS = 0x92, /* not useful, link is always up */
+ CMD_ETHERNET_MODE = 0x99, /* unknown, needed during init */
+};
+
+enum cx82310_status {
+ STATUS_UNDEFINED,
+ STATUS_SUCCESS,
+ STATUS_ERROR,
+ STATUS_UNSUPPORTED,
+ STATUS_UNIMPLEMENTED,
+ STATUS_PARAMETER_ERROR,
+ STATUS_DBG_LOOPBACK,
+};
+
+#define CMD_PACKET_SIZE 64
+#define CMD_TIMEOUT 100
+#define CMD_REPLY_RETRY 5
+
+#define CX82310_MTU 1514
+#define CMD_EP 0x01
+
+struct cx82310_priv {
+ struct work_struct reenable_work;
+ struct usbnet *dev;
+};
+
+/*
+ * execute control command
+ * - optionally send some data (command parameters)
+ * - optionally wait for the reply
+ * - optionally read some data from the reply
+ */
+static int cx82310_cmd(struct usbnet *dev, enum cx82310_cmd cmd, bool reply,
+ u8 *wdata, int wlen, u8 *rdata, int rlen)
+{
+ int actual_len, retries, ret;
+ struct usb_device *udev = dev->udev;
+ u8 *buf = kzalloc(CMD_PACKET_SIZE, GFP_KERNEL);
+
+ if (!buf)
+ return -ENOMEM;
+
+ /* create command packet */
+ buf[0] = cmd;
+ if (wdata)
+ memcpy(buf + 4, wdata, min_t(int, wlen, CMD_PACKET_SIZE - 4));
+
+ /* send command packet */
+ ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, CMD_EP), buf,
+ CMD_PACKET_SIZE, &actual_len, CMD_TIMEOUT);
+ if (ret < 0) {
+ if (cmd != CMD_GET_LINK_STATUS)
+ netdev_err(dev->net, "send command %#x: error %d\n",
+ cmd, ret);
+ goto end;
+ }
+
+ if (reply) {
+ /* wait for reply, retry if it's empty */
+ for (retries = 0; retries < CMD_REPLY_RETRY; retries++) {
+ ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, CMD_EP),
+ buf, CMD_PACKET_SIZE, &actual_len,
+ CMD_TIMEOUT);
+ if (ret < 0) {
+ if (cmd != CMD_GET_LINK_STATUS)
+ netdev_err(dev->net, "reply receive error %d\n",
+ ret);
+ goto end;
+ }
+ if (actual_len > 0)
+ break;
+ }
+ if (actual_len == 0) {
+ netdev_err(dev->net, "no reply to command %#x\n", cmd);
+ ret = -EIO;
+ goto end;
+ }
+ if (buf[0] != cmd) {
+ netdev_err(dev->net, "got reply to command %#x, expected: %#x\n",
+ buf[0], cmd);
+ ret = -EIO;
+ goto end;
+ }
+ if (buf[1] != STATUS_SUCCESS) {
+ netdev_err(dev->net, "command %#x failed: %#x\n", cmd,
+ buf[1]);
+ ret = -EIO;
+ goto end;
+ }
+ if (rdata)
+ memcpy(rdata, buf + 4,
+ min_t(int, rlen, CMD_PACKET_SIZE - 4));
+ }
+end:
+ kfree(buf);
+ return ret;
+}
+
+static int cx82310_enable_ethernet(struct usbnet *dev)
+{
+ int ret = cx82310_cmd(dev, CMD_ETHERNET_MODE, true, "\x01", 1, NULL, 0);
+
+ if (ret)
+ netdev_err(dev->net, "unable to enable ethernet mode: %d\n",
+ ret);
+ return ret;
+}
+
+static void cx82310_reenable_work(struct work_struct *work)
+{
+ struct cx82310_priv *priv = container_of(work, struct cx82310_priv,
+ reenable_work);
+ cx82310_enable_ethernet(priv->dev);
+}
+
+#define partial_len data[0] /* length of partial packet data */
+#define partial_rem data[1] /* remaining (missing) data length */
+#define partial_data data[2] /* partial packet data */
+
+static int cx82310_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+ int ret;
+ char buf[15];
+ struct usb_device *udev = dev->udev;
+ u8 link[3];
+ int timeout = 50;
+ struct cx82310_priv *priv;
+ u8 addr[ETH_ALEN];
+
+ /* avoid ADSL modems - continue only if iProduct is "USB NET CARD" */
+ if (usb_string(udev, udev->descriptor.iProduct, buf, sizeof(buf)) > 0
+ && strcmp(buf, "USB NET CARD")) {
+ dev_info(&udev->dev, "ignoring: probably an ADSL modem\n");
+ return -ENODEV;
+ }
+
+ ret = usbnet_get_endpoints(dev, intf);
+ if (ret)
+ return ret;
+
+ /*
+ * this must not include ethernet header as the device can send partial
+ * packets with no header (and sometimes even empty URBs)
+ */
+ dev->net->hard_header_len = 0;
+ /* we can send at most 1514 bytes of data (+ 2-byte header) per URB */
+ dev->hard_mtu = CX82310_MTU + 2;
+ /* we can receive URBs up to 4KB from the device */
+ dev->rx_urb_size = 4096;
+
+ dev->partial_data = (unsigned long) kmalloc(dev->hard_mtu, GFP_KERNEL);
+ if (!dev->partial_data)
+ return -ENOMEM;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto err_partial;
+ }
+ dev->driver_priv = priv;
+ INIT_WORK(&priv->reenable_work, cx82310_reenable_work);
+ priv->dev = dev;
+
+ /* wait for firmware to become ready (indicated by the link being up) */
+ while (--timeout) {
+ ret = cx82310_cmd(dev, CMD_GET_LINK_STATUS, true, NULL, 0,
+ link, sizeof(link));
+ /* the command can time out during boot - it's not an error */
+ if (!ret && link[0] == 1 && link[2] == 1)
+ break;
+ msleep(500);
+ }
+ if (!timeout) {
+ netdev_err(dev->net, "firmware not ready in time\n");
+ ret = -ETIMEDOUT;
+ goto err;
+ }
+
+ /* enable ethernet mode (?) */
+ ret = cx82310_enable_ethernet(dev);
+ if (ret)
+ goto err;
+
+ /* get the MAC address */
+ ret = cx82310_cmd(dev, CMD_GET_MAC_ADDR, true, NULL, 0, addr, ETH_ALEN);
+ if (ret) {
+ netdev_err(dev->net, "unable to read MAC address: %d\n", ret);
+ goto err;
+ }
+ eth_hw_addr_set(dev->net, addr);
+
+ /* start (does not seem to have any effect?) */
+ ret = cx82310_cmd(dev, CMD_START, false, NULL, 0, NULL, 0);
+ if (ret)
+ goto err;
+
+ return 0;
+err:
+ kfree(dev->driver_priv);
+err_partial:
+ kfree((void *)dev->partial_data);
+ return ret;
+}
+
+static void cx82310_unbind(struct usbnet *dev, struct usb_interface *intf)
+{
+ struct cx82310_priv *priv = dev->driver_priv;
+
+ kfree((void *)dev->partial_data);
+ cancel_work_sync(&priv->reenable_work);
+ kfree(dev->driver_priv);
+}
+
+/*
+ * RX is NOT easy - we can receive multiple packets per skb, each having 2-byte
+ * packet length at the beginning.
+ * The last packet might be incomplete (when it crosses the 4KB URB size),
+ * continuing in the next skb (without any headers).
+ * If a packet has odd length, there is one extra byte at the end (before next
+ * packet or at the end of the URB).
+ */
+static int cx82310_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+{
+ int len;
+ struct sk_buff *skb2;
+ struct cx82310_priv *priv = dev->driver_priv;
+
+ /*
+ * If the last skb ended with an incomplete packet, this skb contains
+ * end of that packet at the beginning.
+ */
+ if (dev->partial_rem) {
+ len = dev->partial_len + dev->partial_rem;
+ skb2 = alloc_skb(len, GFP_ATOMIC);
+ if (!skb2)
+ return 0;
+ skb_put(skb2, len);
+ memcpy(skb2->data, (void *)dev->partial_data,
+ dev->partial_len);
+ memcpy(skb2->data + dev->partial_len, skb->data,
+ dev->partial_rem);
+ usbnet_skb_return(dev, skb2);
+ skb_pull(skb, (dev->partial_rem + 1) & ~1);
+ dev->partial_rem = 0;
+ if (skb->len < 2)
+ return 1;
+ }
+
+ /* a skb can contain multiple packets */
+ while (skb->len > 1) {
+ /* first two bytes are packet length */
+ len = skb->data[0] | (skb->data[1] << 8);
+ skb_pull(skb, 2);
+
+ /* if last packet in the skb, let usbnet to process it */
+ if (len == skb->len || len + 1 == skb->len) {
+ skb_trim(skb, len);
+ break;
+ }
+
+ if (len == 0xffff) {
+ netdev_info(dev->net, "router was rebooted, re-enabling ethernet mode");
+ schedule_work(&priv->reenable_work);
+ } else if (len > CX82310_MTU) {
+ netdev_err(dev->net, "RX packet too long: %d B\n", len);
+ return 0;
+ }
+
+ /* incomplete packet, save it for the next skb */
+ if (len > skb->len) {
+ dev->partial_len = skb->len;
+ dev->partial_rem = len - skb->len;
+ memcpy((void *)dev->partial_data, skb->data,
+ dev->partial_len);
+ skb_pull(skb, skb->len);
+ break;
+ }
+
+ skb2 = alloc_skb(len, GFP_ATOMIC);
+ if (!skb2)
+ return 0;
+ skb_put(skb2, len);
+ memcpy(skb2->data, skb->data, len);
+ /* process the packet */
+ usbnet_skb_return(dev, skb2);
+
+ skb_pull(skb, (len + 1) & ~1);
+ }
+
+ /* let usbnet process the last packet */
+ return 1;
+}
+
+/* TX is easy, just add 2 bytes of length at the beginning */
+static struct sk_buff *cx82310_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
+ gfp_t flags)
+{
+ int len = skb->len;
+
+ if (skb_cow_head(skb, 2)) {
+ dev_kfree_skb_any(skb);
+ return NULL;
+ }
+ skb_push(skb, 2);
+
+ skb->data[0] = len;
+ skb->data[1] = len >> 8;
+
+ return skb;
+}
+
+
+static const struct driver_info cx82310_info = {
+ .description = "Conexant CX82310 USB ethernet",
+ .flags = FLAG_ETHER,
+ .bind = cx82310_bind,
+ .unbind = cx82310_unbind,
+ .rx_fixup = cx82310_rx_fixup,
+ .tx_fixup = cx82310_tx_fixup,
+};
+
+#define USB_DEVICE_CLASS(vend, prod, cl, sc, pr) \
+ .match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
+ USB_DEVICE_ID_MATCH_DEV_INFO, \
+ .idVendor = (vend), \
+ .idProduct = (prod), \
+ .bDeviceClass = (cl), \
+ .bDeviceSubClass = (sc), \
+ .bDeviceProtocol = (pr)
+
+static const struct usb_device_id products[] = {
+ {
+ USB_DEVICE_CLASS(0x0572, 0xcb01, 0xff, 0, 0),
+ .driver_info = (unsigned long) &cx82310_info
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(usb, products);
+
+static struct usb_driver cx82310_driver = {
+ .name = "cx82310_eth",
+ .id_table = products,
+ .probe = usbnet_probe,
+ .disconnect = usbnet_disconnect,
+ .suspend = usbnet_suspend,
+ .resume = usbnet_resume,
+ .disable_hub_initiated_lpm = 1,
+};
+
+module_usb_driver(cx82310_driver);
+
+MODULE_AUTHOR("Ondrej Zary");
+MODULE_DESCRIPTION("Conexant CX82310-based ADSL router USB ethernet driver");
+MODULE_LICENSE("GPL");