diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/net/usb/cx82310_eth.c | 375 |
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"); |