| // 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"); |