From 7ad65bf68d705b445ef10b77ab50dab22be185ee Mon Sep 17 00:00:00 2001 From: "sjur.brandeland@stericsson.com" Date: Sun, 4 Dec 2011 11:22:53 +0000 Subject: caif: Add support for CAIF over CDC NCM USB interface MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit NCM 1.0 does not support anything but Ethernet framing, hence CAIF payload will be put into Ethernet frames. Discovery is based on fixed USB vendor 0x04cc (ST-Ericsson), product-id 0x230f (NCM). In this variant only CAIF payload is sent over the NCM interface. The CAIF stack (cfusbl.c) will when USB interface register first check if we got a CDC NCM USB interface with the right VID, PID. It will then read the device's Ethernet address and create a 'template' Ethernet TX header, using a broadcast address as the destination address, and EthType 0x88b5 (802.1 Local Experimental - vendor specific). A protocol handler for 0x88b5 is setup for reception of CAIF frames from the CDC NCM USB interface. Signed-off-by: Sjur Brændeland Signed-off-by: David S. Miller --- net/caif/caif_usb.c | 208 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 208 insertions(+) create mode 100644 net/caif/caif_usb.c (limited to 'net/caif/caif_usb.c') diff --git a/net/caif/caif_usb.c b/net/caif/caif_usb.c new file mode 100644 index 000000000000..f5db57c58081 --- /dev/null +++ b/net/caif/caif_usb.c @@ -0,0 +1,208 @@ +/* + * CAIF USB handler + * Copyright (C) ST-Ericsson AB 2011 + * Author: Sjur Brendeland/sjur.brandeland@stericsson.com + * License terms: GNU General Public License (GPL) version 2 + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +MODULE_LICENSE("GPL"); + +#define CFUSB_PAD_DESCR_SZ 1 /* Alignment descriptor length */ +#define CFUSB_ALIGNMENT 4 /* Number of bytes to align. */ +#define CFUSB_MAX_HEADLEN (CFUSB_PAD_DESCR_SZ + CFUSB_ALIGNMENT-1) +#define STE_USB_VID 0x04cc /* USB Product ID for ST-Ericsson */ +#define STE_USB_PID_CAIF 0x2306 /* Product id for CAIF Modems */ + +struct cfusbl { + struct cflayer layer; + u8 tx_eth_hdr[ETH_HLEN]; +}; + +static bool pack_added; + +static int cfusbl_receive(struct cflayer *layr, struct cfpkt *pkt) +{ + u8 hpad; + + /* Remove padding. */ + cfpkt_extr_head(pkt, &hpad, 1); + cfpkt_extr_head(pkt, NULL, hpad); + return layr->up->receive(layr->up, pkt); +} + +static int cfusbl_transmit(struct cflayer *layr, struct cfpkt *pkt) +{ + struct caif_payload_info *info; + u8 hpad; + u8 zeros[CFUSB_ALIGNMENT]; + struct sk_buff *skb; + struct cfusbl *usbl = container_of(layr, struct cfusbl, layer); + + skb = cfpkt_tonative(pkt); + + skb_reset_network_header(skb); + skb->protocol = htons(ETH_P_IP); + + info = cfpkt_info(pkt); + hpad = (info->hdr_len + CFUSB_PAD_DESCR_SZ) & (CFUSB_ALIGNMENT - 1); + + if (skb_headroom(skb) < ETH_HLEN + CFUSB_PAD_DESCR_SZ + hpad) { + pr_warn("Headroom to small\n"); + kfree_skb(skb); + return -EIO; + } + memset(zeros, 0, hpad); + + cfpkt_add_head(pkt, zeros, hpad); + cfpkt_add_head(pkt, &hpad, 1); + cfpkt_add_head(pkt, usbl->tx_eth_hdr, sizeof(usbl->tx_eth_hdr)); + return layr->dn->transmit(layr->dn, pkt); +} + +static void cfusbl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl, + int phyid) +{ + if (layr->up && layr->up->ctrlcmd) + layr->up->ctrlcmd(layr->up, ctrl, layr->id); +} + +struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN], + u8 braddr[ETH_ALEN]) +{ + struct cfusbl *this = kmalloc(sizeof(struct cfusbl), GFP_ATOMIC); + + if (!this) { + pr_warn("Out of memory\n"); + return NULL; + } + caif_assert(offsetof(struct cfusbl, layer) == 0); + + memset(this, 0, sizeof(struct cflayer)); + this->layer.receive = cfusbl_receive; + this->layer.transmit = cfusbl_transmit; + this->layer.ctrlcmd = cfusbl_ctrlcmd; + snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "usb%d", phyid); + this->layer.id = phyid; + + /* + * Construct TX ethernet header: + * 0-5 destination address + * 5-11 source address + * 12-13 protocol type + */ + memcpy(&this->tx_eth_hdr[ETH_ALEN], braddr, ETH_ALEN); + memcpy(&this->tx_eth_hdr[ETH_ALEN], ethaddr, ETH_ALEN); + this->tx_eth_hdr[12] = cpu_to_be16(ETH_P_802_EX1) & 0xff; + this->tx_eth_hdr[13] = (cpu_to_be16(ETH_P_802_EX1) >> 8) & 0xff; + pr_debug("caif ethernet TX-header dst:%pM src:%pM type:%02x%02x\n", + this->tx_eth_hdr, this->tx_eth_hdr + ETH_ALEN, + this->tx_eth_hdr[12], this->tx_eth_hdr[13]); + + return (struct cflayer *) this; +} + +static struct packet_type caif_usb_type __read_mostly = { + .type = cpu_to_be16(ETH_P_802_EX1), +}; + +static int cfusbl_device_notify(struct notifier_block *me, unsigned long what, + void *arg) +{ + struct net_device *dev = arg; + struct caif_dev_common common; + struct cflayer *layer, *link_support; + struct usbnet *usbnet = netdev_priv(dev); + struct usb_device *usbdev = usbnet->udev; + struct ethtool_drvinfo drvinfo; + + /* + * Quirks: High-jack ethtool to find if we have a NCM device, + * and find it's VID/PID. + */ + if (dev->ethtool_ops == NULL || dev->ethtool_ops->get_drvinfo == NULL) + return 0; + + dev->ethtool_ops->get_drvinfo(dev, &drvinfo); + if (strncmp(drvinfo.driver, "cdc_ncm", 7) != 0) + return 0; + + pr_debug("USB CDC NCM device VID:0x%4x PID:0x%4x\n", + le16_to_cpu(usbdev->descriptor.idVendor), + le16_to_cpu(usbdev->descriptor.idProduct)); + + /* Check for VID/PID that supports CAIF */ + if (!(le16_to_cpu(usbdev->descriptor.idVendor) == STE_USB_VID && + le16_to_cpu(usbdev->descriptor.idProduct) == STE_USB_PID_CAIF)) + return 0; + + if (what == NETDEV_UNREGISTER) + module_put(THIS_MODULE); + + if (what != NETDEV_REGISTER) + return 0; + + __module_get(THIS_MODULE); + + memset(&common, 0, sizeof(common)); + common.use_frag = false; + common.use_fcs = false; + common.use_stx = false; + common.link_select = CAIF_LINK_HIGH_BANDW; + common.flowctrl = NULL; + + link_support = cfusbl_create(dev->ifindex, dev->dev_addr, + dev->broadcast); + + if (!link_support) + return -ENOMEM; + + if (dev->num_tx_queues > 1) + pr_warn("USB device uses more than one tx queue\n"); + + caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN, + &layer, &caif_usb_type.func); + if (!pack_added) + dev_add_pack(&caif_usb_type); + pack_added = 1; + + strncpy(layer->name, dev->name, + sizeof(layer->name) - 1); + layer->name[sizeof(layer->name) - 1] = 0; + + return 0; +} + +static struct notifier_block caif_device_notifier = { + .notifier_call = cfusbl_device_notify, + .priority = 0, +}; + +static int __init cfusbl_init(void) +{ + return register_netdevice_notifier(&caif_device_notifier); +} + +static void __exit cfusbl_exit(void) +{ + unregister_netdevice_notifier(&caif_device_notifier); + dev_remove_pack(&caif_usb_type); +} + +module_init(cfusbl_init); +module_exit(cfusbl_exit); -- cgit v1.2.3