usb: gadget: add u_qc_ether - QC Ethernet-over-USB link layer utilities.
This utilities is based on Ethernet-over-USB link layer utilities and
contains QC specific implementation (using SPS BAM-to-BAM for data
channel).
Change-Id: Iec417b4df57c34d1ba9368495c7a489c36ddf6dc
Signed-off-by: Ofir Cohen <ofirc@codeaurora.org>
diff --git a/drivers/usb/gadget/u_qc_ether.c b/drivers/usb/gadget/u_qc_ether.c
new file mode 100644
index 0000000..20933b6
--- /dev/null
+++ b/drivers/usb/gadget/u_qc_ether.c
@@ -0,0 +1,409 @@
+/*
+ * u_qc_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
+ *
+ * Copyright (C) 2003-2005,2008 David Brownell
+ * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
+ * Copyright (C) 2008 Nokia Corporation
+ * Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/* #define VERBOSE_DEBUG */
+
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/device.h>
+#include <linux/ctype.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+
+#include "u_ether.h"
+
+
+/*
+ * This component encapsulates the Ethernet link glue needed to provide
+ * one (!) network link through the USB gadget stack, normally "usb0".
+ *
+ * The control and data models are handled by the function driver which
+ * connects to this code; such as CDC Ethernet (ECM or EEM),
+ * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
+ * management.
+ *
+ * Link level addressing is handled by this component using module
+ * parameters; if no such parameters are provided, random link level
+ * addresses are used. Each end of the link uses one address. The
+ * host end address is exported in various ways, and is often recorded
+ * in configuration databases.
+ *
+ * The driver which assembles each configuration using such a link is
+ * responsible for ensuring that each configuration includes at most one
+ * instance of is network link. (The network layer provides ways for
+ * this single "physical" link to be used by multiple virtual links.)
+ *
+ * This utilities is based on Ethernet-over-USB link layer utilities and
+ * contains MSM specific implementation.
+ */
+
+#define UETH__VERSION "29-May-2008"
+
+struct eth_qc_dev {
+ /* lock is held while accessing port_usb
+ * or updating its backlink port_usb->ioport
+ */
+ spinlock_t lock;
+ struct qc_gether *port_usb;
+
+ struct net_device *net;
+ struct usb_gadget *gadget;
+
+ unsigned header_len;
+
+ bool zlp;
+ u8 host_mac[ETH_ALEN];
+};
+
+/*-------------------------------------------------------------------------*/
+
+#undef DBG
+#undef VDBG
+#undef ERROR
+#undef INFO
+
+#define xprintk(d, level, fmt, args...) \
+ printk(level "%s: " fmt , (d)->net->name , ## args)
+
+#ifdef DEBUG
+#undef DEBUG
+#define DBG(dev, fmt, args...) \
+ xprintk(dev , KERN_DEBUG , fmt , ## args)
+#else
+#define DBG(dev, fmt, args...) \
+ do { } while (0)
+#endif /* DEBUG */
+
+#ifdef VERBOSE_DEBUG
+#define VDBG DBG
+#else
+#define VDBG(dev, fmt, args...) \
+ do { } while (0)
+#endif /* DEBUG */
+
+#define ERROR(dev, fmt, args...) \
+ xprintk(dev , KERN_ERR , fmt , ## args)
+#define INFO(dev, fmt, args...) \
+ xprintk(dev , KERN_INFO , fmt , ## args)
+
+/*-------------------------------------------------------------------------*/
+
+/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
+static int ueth_qc_change_mtu(struct net_device *net, int new_mtu)
+{
+ struct eth_qc_dev *dev = netdev_priv(net);
+ unsigned long flags;
+ int status = 0;
+
+ /* don't change MTU on "live" link (peer won't know) */
+ spin_lock_irqsave(&dev->lock, flags);
+ if (dev->port_usb)
+ status = -EBUSY;
+ else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
+ status = -ERANGE;
+ else
+ net->mtu = new_mtu;
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ return status;
+}
+
+static void eth_qc_get_drvinfo(struct net_device *net,
+ struct ethtool_drvinfo *p)
+{
+ struct eth_qc_dev *dev = netdev_priv(net);
+
+ strlcpy(p->driver, "g_qc_ether", sizeof p->driver);
+ strlcpy(p->version, UETH__VERSION, sizeof p->version);
+ strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version);
+ strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info);
+}
+
+static const struct ethtool_ops qc_ethtool_ops = {
+ .get_drvinfo = eth_qc_get_drvinfo,
+ .get_link = ethtool_op_get_link,
+};
+
+static netdev_tx_t eth_qc_start_xmit(struct sk_buff *skb,
+ struct net_device *net)
+{
+ return NETDEV_TX_OK;
+}
+
+static int eth_qc_open(struct net_device *net)
+{
+ struct eth_qc_dev *dev = netdev_priv(net);
+ struct qc_gether *link;
+
+ DBG(dev, "%s\n", __func__);
+ if (netif_carrier_ok(dev->net)) {
+ /* Force the netif to send the RTM_NEWLINK event
+ * that in use to notify on the USB cable status.
+ */
+ netif_carrier_off(dev->net);
+ netif_carrier_on(dev->net);
+ netif_wake_queue(dev->net);
+ }
+
+ spin_lock_irq(&dev->lock);
+ link = dev->port_usb;
+ if (link && link->open)
+ link->open(link);
+ spin_unlock_irq(&dev->lock);
+
+ return 0;
+}
+
+static int eth_qc_stop(struct net_device *net)
+{
+ struct eth_qc_dev *dev = netdev_priv(net);
+ unsigned long flags;
+ struct qc_gether *link = dev->port_usb;
+
+ VDBG(dev, "%s\n", __func__);
+ netif_stop_queue(net);
+
+ spin_lock_irqsave(&dev->lock, flags);
+ if (dev->port_usb && link->close)
+ link->close(link);
+ spin_unlock_irqrestore(&dev->lock, flags);
+
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
+static char *qc_dev_addr;
+module_param(qc_dev_addr, charp, S_IRUGO);
+MODULE_PARM_DESC(qc_dev_addr, "QC Device Ethernet Address");
+
+/* this address is invisible to ifconfig */
+static char *qc_host_addr;
+module_param(qc_host_addr, charp, S_IRUGO);
+MODULE_PARM_DESC(qc_host_addr, "QC Host Ethernet Address");
+
+static int get_qc_ether_addr(const char *str, u8 *dev_addr)
+{
+ if (str) {
+ unsigned i;
+
+ for (i = 0; i < 6; i++) {
+ unsigned char num;
+
+ if ((*str == '.') || (*str == ':'))
+ str++;
+ num = hex_to_bin(*str++) << 4;
+ num |= hex_to_bin(*str++);
+ dev_addr[i] = num;
+ }
+ if (is_valid_ether_addr(dev_addr))
+ return 0;
+ }
+ random_ether_addr(dev_addr);
+ return 1;
+}
+
+static struct eth_qc_dev *qc_dev;
+
+static const struct net_device_ops eth_qc_netdev_ops = {
+ .ndo_open = eth_qc_open,
+ .ndo_stop = eth_qc_stop,
+ .ndo_start_xmit = eth_qc_start_xmit,
+ .ndo_change_mtu = ueth_qc_change_mtu,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_validate_addr = eth_validate_addr,
+};
+
+static struct device_type qc_gadget_type = {
+ .name = "gadget",
+};
+
+/**
+ * gether_qc_setup - initialize one ethernet-over-usb link
+ * @g: gadget to associated with these links
+ * @ethaddr: NULL, or a buffer in which the ethernet address of the
+ * host side of the link is recorded
+ * Context: may sleep
+ *
+ * This sets up the single network link that may be exported by a
+ * gadget driver using this framework. The link layer addresses are
+ * set up using module parameters.
+ *
+ * Returns negative errno, or zero on success
+ */
+int gether_qc_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN])
+{
+ return gether_qc_setup_name(g, ethaddr, "usb");
+}
+
+/**
+ * gether_qc_setup_name - initialize one ethernet-over-usb link
+ * @g: gadget to associated with these links
+ * @ethaddr: NULL, or a buffer in which the ethernet address of the
+ * host side of the link is recorded
+ * @netname: name for network device (for example, "usb")
+ * Context: may sleep
+ *
+ * This sets up the single network link that may be exported by a
+ * gadget driver using this framework. The link layer addresses are
+ * set up using module parameters.
+ *
+ * Returns negative errno, or zero on success
+ */
+int gether_qc_setup_name(struct usb_gadget *g, u8 ethaddr[ETH_ALEN],
+ const char *netname)
+{
+ struct eth_qc_dev *dev;
+ struct net_device *net;
+ int status;
+
+ if (qc_dev)
+ return -EBUSY;
+
+ net = alloc_etherdev(sizeof *dev);
+ if (!net)
+ return -ENOMEM;
+
+ dev = netdev_priv(net);
+ spin_lock_init(&dev->lock);
+
+ /* network device setup */
+ dev->net = net;
+ snprintf(net->name, sizeof(net->name), "%s%%d", netname);
+
+ if (get_qc_ether_addr(qc_dev_addr, net->dev_addr))
+ dev_warn(&g->dev,
+ "using random %s ethernet address\n", "self");
+ if (get_qc_ether_addr(qc_host_addr, dev->host_mac))
+ dev_warn(&g->dev,
+ "using random %s ethernet address\n", "host");
+
+ if (ethaddr)
+ memcpy(ethaddr, dev->host_mac, ETH_ALEN);
+
+ net->netdev_ops = ð_qc_netdev_ops;
+
+ SET_ETHTOOL_OPS(net, &qc_ethtool_ops);
+
+ netif_carrier_off(net);
+
+ dev->gadget = g;
+ SET_NETDEV_DEV(net, &g->dev);
+ SET_NETDEV_DEVTYPE(net, &qc_gadget_type);
+
+ status = register_netdev(net);
+ if (status < 0) {
+ dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
+ free_netdev(net);
+ } else {
+ INFO(dev, "MAC %pM\n", net->dev_addr);
+ INFO(dev, "HOST MAC %pM\n", dev->host_mac);
+
+ qc_dev = dev;
+ }
+
+ return status;
+}
+
+/**
+ * gether_qc_cleanup - remove Ethernet-over-USB device
+ * Context: may sleep
+ *
+ * This is called to free all resources allocated by @gether_qc_setup().
+ */
+void gether_qc_cleanup(void)
+{
+ if (!qc_dev)
+ return;
+
+ unregister_netdev(qc_dev->net);
+ free_netdev(qc_dev->net);
+
+ qc_dev = NULL;
+}
+
+
+/**
+ * gether_qc_connect - notify network layer that USB link is active
+ * @link: the USB link, set up with endpoints, descriptors matching
+ * current device speed, and any framing wrapper(s) set up.
+ * Context: irqs blocked
+ *
+ * This is called to let the network layer know the connection
+ * is active ("carrier detect").
+ */
+struct net_device *gether_qc_connect(struct qc_gether *link)
+{
+ struct eth_qc_dev *dev = qc_dev;
+
+ if (!dev)
+ return ERR_PTR(-EINVAL);
+
+ dev->zlp = link->is_zlp_ok;
+ dev->header_len = link->header_len;
+
+ spin_lock(&dev->lock);
+ dev->port_usb = link;
+ link->ioport = dev;
+ if (netif_running(dev->net)) {
+ if (link->open)
+ link->open(link);
+ } else {
+ if (link->close)
+ link->close(link);
+ }
+ spin_unlock(&dev->lock);
+
+ netif_carrier_on(dev->net);
+ if (netif_running(dev->net))
+ netif_wake_queue(dev->net);
+
+ return dev->net;
+}
+
+/**
+ * gether_qc_disconnect - notify network layer that USB link is inactive
+ * @link: the USB link, on which gether_connect() was called
+ * Context: irqs blocked
+ *
+ * This is called to let the network layer know the connection
+ * went inactive ("no carrier").
+ *
+ * On return, the state is as if gether_connect() had never been called.
+ */
+void gether_qc_disconnect(struct qc_gether *link)
+{
+ struct eth_qc_dev *dev = link->ioport;
+
+ if (!dev)
+ return;
+
+ DBG(dev, "%s\n", __func__);
+
+ netif_stop_queue(dev->net);
+ netif_carrier_off(dev->net);
+
+ spin_lock(&dev->lock);
+ dev->port_usb = NULL;
+ link->ioport = NULL;
+ spin_unlock(&dev->lock);
+}
diff --git a/drivers/usb/gadget/u_qc_ether.h b/drivers/usb/gadget/u_qc_ether.h
new file mode 100644
index 0000000..b3c281b
--- /dev/null
+++ b/drivers/usb/gadget/u_qc_ether.h
@@ -0,0 +1,97 @@
+/*
+ * u_qc_ether.h -- interface to USB gadget "ethernet link" utilities
+ *
+ * Copyright (C) 2003-2005,2008 David Brownell
+ * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
+ * Copyright (C) 2008 Nokia Corporation
+ * Copyright (c) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef __U_QC_ETHER_H
+#define __U_QC_ETHER_H
+
+#include <linux/err.h>
+#include <linux/if_ether.h>
+#include <linux/usb/composite.h>
+#include <linux/usb/cdc.h>
+
+#include "gadget_chips.h"
+
+
+/*
+ * This represents the USB side of an "ethernet" link, managed by a USB
+ * function which provides control and (maybe) framing. Two functions
+ * in different configurations could share the same ethernet link/netdev,
+ * using different host interaction models.
+ *
+ * There is a current limitation that only one instance of this link may
+ * be present in any given configuration. When that's a problem, network
+ * layer facilities can be used to package multiple logical links on this
+ * single "physical" one.
+ *
+ * This function is based on Ethernet-over-USB link layer utilities and
+ * contains MSM specific implementation.
+ */
+
+struct qc_gether {
+ struct usb_function func;
+
+ /* updated by gether_{connect,disconnect} */
+ struct eth_qc_dev *ioport;
+
+ /* endpoints handle full and/or high speeds */
+ struct usb_ep *in_ep;
+ struct usb_ep *out_ep;
+
+ bool is_zlp_ok;
+
+ u16 cdc_filter;
+
+ /* hooks for added framing, as needed for RNDIS and EEM. */
+ u32 header_len;
+ /* NCM requires fixed size bundles */
+ bool is_fixed;
+ u32 fixed_out_len;
+ u32 fixed_in_len;
+ struct sk_buff *(*wrap)(struct qc_gether *port,
+ struct sk_buff *skb);
+ int (*unwrap)(struct qc_gether *port,
+ struct sk_buff *skb,
+ struct sk_buff_head *list);
+
+ /* called on network open/close */
+ void (*open)(struct qc_gether *);
+ void (*close)(struct qc_gether *);
+};
+
+/* netdev setup/teardown as directed by the gadget driver */
+int gether_qc_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]);
+void gether_qc_cleanup(void);
+/* variant of gether_setup that allows customizing network device name */
+int gether_qc_setup_name(struct usb_gadget *g, u8 ethaddr[ETH_ALEN],
+ const char *netname);
+
+/* connect/disconnect is handled by individual functions */
+struct net_device *gether_qc_connect(struct qc_gether *);
+void gether_qc_disconnect(struct qc_gether *);
+
+/* each configuration may bind one instance of an ethernet link */
+int ecm_qc_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
+
+int
+rndis_qc_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
+ u32 vendorID, const char *manufacturer,
+ u8 maxPktPerXfer);
+#endif /* __U_QC_ETHER_H */